Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Stormy weather has Hohenfels and the volks wet, chilly, and looking for places to run their gear.
Speaking of gear, today’s little post is on the importance of our gear.
First, a couple questions to all our readers… how important is having the most up to date gear? How do you feel about all the bells and whistles? Do you need all the latest cameras and accessories? Answer on the Hohenfels Volks Facebook page, to have your say.
The simple fact is that most folks out there haven’t even mastered their favorite features on the gear they have. If you can nail your exposures and desired images every time, and feel that moving up is right, then go for it. Even if you can’t, go for it if that’s what you want. However, the newest cameras and gear won’t make your images better, they won’t improve and perfect your composition, they won’t do more for you.
Learn what you have, get great at using the features you need and use on a regular basis, then move on as your photography grows.
Just my 2 cents. Have a great evening, everyone, and enjoy the rest of the week. It’s almost time for a couple days of shooting!
I’d love to know what you think and what you’re doing with your photography. Where are you headed, and is there anything you’d like to see here? Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Thursday, May 31, 2012
Tuesday, May 29, 2012
Back to Basics...
Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! I hope this lovely evening finds you relaxed and excited about photography here in Hohenfels.
Today we’re going back to basics. We’re talking about one side of the “exposure triangle,” shutter speed.
Shutter speed is, of course, how fast your shutter opens and returns to the closed position. That sounds simple, but like all things in photography, it involves much more than that. Because SLRs use a single moving mirror to allow the composing of an image through your lens, and focusing through the lens, also, that has to be factored in. In long exposures, this can lead to vibrations and shake.
The complexities that go into allowing super fast shutter speeds are too many to discuss here, but we will touch on a couple issues.
Today’s shutters are usually made of metal blades, allowing them slide behind one another and achieve faster speeds. Because they are firm, they are also more durable. Early SLRs used silk shutters, which could snag and tear, or even develop pinholes, causing a waste of entire rolls of film. Most of the SLRs you’re likely to have encountered have curtain shutters that slide up and down. On older cameras, leaf shutters were common, which allowed flash synchronization at all speeds. They generally couldn’t achieve reliable speeds above 1/500 at the top end. They also used clockwork like mechanisms to open the shutter exposing the entire shot or sensor simultaneously to whatever light was present and exposed for.
On today’s cameras, shutter speeds that are very fast do not expose the entire sensor at once. Instead, they use a pair of “curtains” that travel along the focal plane and are synchronized to create a slit of light that progresses until the entirety of the sensor has been exposed. Due to this fact, most entry-level cameras can flash synch anywhere from 1/60-1/200, with high-end dSLRs being capable of synching up to 1/250. If you use your flash at any shutter speed faster than your sync speed, you will have dark bands along part of your scene.
Each halving or doubling of your shutter speed causes a doubling or halving of the exposure to which your sensor is exposed. Most of our better modern cameras can shoot from 30 seconds to 1/8000 second, and include a bulb mode for manual exposures longer than 30 seconds.
The series of shutter speeds, in full stops goes like this:
30 seconds, 15 seconds, 8 seconds, 4 seconds, 2 seconds, 1 second, ½, ¼, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, 1/2000, 1/4000, and 1/8000. Notice the halving of exposure with each change of speed.
Adding in half stops gives you:
24 seconds, 12 seconds, 6 seconds, 3 seconds, 1.5 seconds, 1/3, 1/6, 1/10, 1/20, 1/45, 1/90, 1/180, 1/350, 1/750, 1/1500, 1/3000, and 1/6000.
Finally adding in the third stop increments gives you the following series:
13 seconds, 10 seconds, 6 seconds, 5 seconds, 3 seconds, 2.5 seconds, 1.6 seconds, 1.3 seconds, .6 second, .4 second, 1/5, 1/6, 1/10, 1/13, 1/20, 1/25, 1/40, 1/50, 1/80, 1/100, 1/160, 1/200, 1/320, 1/400, 1/640, 1/800, 1/1250, 1/1600, 1/2500, 1/3200, 1/5000, and finally 1/6400.
The complete range allows for shooting in all lighting situations. They also allow for shots that will freeze even the fastest action or blur even the slightest movement. The creative potential of using your shutter speed in combination with the other sides of the triangle is limited only by your imagination. Try some motion blur, or try panning with a moving object to get the sense of motion and speed. Try to capture a hummingbird’s wings without blur. Remember, though, that every change in one side of the triangle requires a change in another side to maintain the same exposure.
Here's a photo, taken at a local fest, that shows how shutter speed can be used creatively.
ISO 125, f/16, 4 seconds
The ferris wheel, with a long exposure for motion blur in the ride, turned into a color wheel!
Back to basics, get there and get the shot using the knowledge you have and your unique vision. I’m convinced that shooting for the basics can help keep us on top of our game and give us another way to expand our potential.
I’d love to know what you think and what you’re doing with your photography. Where are you headed, and is there anything you’d like to see here? Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Today we’re going back to basics. We’re talking about one side of the “exposure triangle,” shutter speed.
Shutter speed is, of course, how fast your shutter opens and returns to the closed position. That sounds simple, but like all things in photography, it involves much more than that. Because SLRs use a single moving mirror to allow the composing of an image through your lens, and focusing through the lens, also, that has to be factored in. In long exposures, this can lead to vibrations and shake.
The complexities that go into allowing super fast shutter speeds are too many to discuss here, but we will touch on a couple issues.
Today’s shutters are usually made of metal blades, allowing them slide behind one another and achieve faster speeds. Because they are firm, they are also more durable. Early SLRs used silk shutters, which could snag and tear, or even develop pinholes, causing a waste of entire rolls of film. Most of the SLRs you’re likely to have encountered have curtain shutters that slide up and down. On older cameras, leaf shutters were common, which allowed flash synchronization at all speeds. They generally couldn’t achieve reliable speeds above 1/500 at the top end. They also used clockwork like mechanisms to open the shutter exposing the entire shot or sensor simultaneously to whatever light was present and exposed for.
On today’s cameras, shutter speeds that are very fast do not expose the entire sensor at once. Instead, they use a pair of “curtains” that travel along the focal plane and are synchronized to create a slit of light that progresses until the entirety of the sensor has been exposed. Due to this fact, most entry-level cameras can flash synch anywhere from 1/60-1/200, with high-end dSLRs being capable of synching up to 1/250. If you use your flash at any shutter speed faster than your sync speed, you will have dark bands along part of your scene.
Each halving or doubling of your shutter speed causes a doubling or halving of the exposure to which your sensor is exposed. Most of our better modern cameras can shoot from 30 seconds to 1/8000 second, and include a bulb mode for manual exposures longer than 30 seconds.
The series of shutter speeds, in full stops goes like this:
30 seconds, 15 seconds, 8 seconds, 4 seconds, 2 seconds, 1 second, ½, ¼, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, 1/2000, 1/4000, and 1/8000. Notice the halving of exposure with each change of speed.
Adding in half stops gives you:
24 seconds, 12 seconds, 6 seconds, 3 seconds, 1.5 seconds, 1/3, 1/6, 1/10, 1/20, 1/45, 1/90, 1/180, 1/350, 1/750, 1/1500, 1/3000, and 1/6000.
Finally adding in the third stop increments gives you the following series:
13 seconds, 10 seconds, 6 seconds, 5 seconds, 3 seconds, 2.5 seconds, 1.6 seconds, 1.3 seconds, .6 second, .4 second, 1/5, 1/6, 1/10, 1/13, 1/20, 1/25, 1/40, 1/50, 1/80, 1/100, 1/160, 1/200, 1/320, 1/400, 1/640, 1/800, 1/1250, 1/1600, 1/2500, 1/3200, 1/5000, and finally 1/6400.
The complete range allows for shooting in all lighting situations. They also allow for shots that will freeze even the fastest action or blur even the slightest movement. The creative potential of using your shutter speed in combination with the other sides of the triangle is limited only by your imagination. Try some motion blur, or try panning with a moving object to get the sense of motion and speed. Try to capture a hummingbird’s wings without blur. Remember, though, that every change in one side of the triangle requires a change in another side to maintain the same exposure.
Here's a photo, taken at a local fest, that shows how shutter speed can be used creatively.
ISO 125, f/16, 4 seconds
The ferris wheel, with a long exposure for motion blur in the ride, turned into a color wheel!
Back to basics, get there and get the shot using the knowledge you have and your unique vision. I’m convinced that shooting for the basics can help keep us on top of our game and give us another way to expand our potential.
I’d love to know what you think and what you’re doing with your photography. Where are you headed, and is there anything you’d like to see here? Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Monday, May 28, 2012
Better Late...
Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Greetings, volks, from Hohenfels. Another weekend passes into the ether of memory, preserved with our cameras and vision.
I hope you’ve had a chance to explore the new layout. By adding our links to another page, we’re able to expand them without limit and improve on the resources we can present. I’m currently working on an advanced section, covering metering, lighting, and other things beyond the basics.
This past weekend provided some excellent opportunities to make some photos and spend some time relaxing. I trust everyone made their shots and got their chill on, as it were.
Here’s what I’m looking at from for future posts. Beginners and Basics, Advanced Concepts and Techniques, Q and A, Composition, both elements and advanced, Reviews, and of course, continuing with our ride along shots and other items. I’d love to hear from everyone out there, if you have a suggestion, idea, or question, let us know through our Facebook link.
I’m going to close this post today with the following photo, made Saturday in Munich. Ride along with me, as we explore the shot as laid out.
Olympiazentrum in Munich.
As you can see, this was taken at Olympia Zentrum, the compound built for the 1972 Munich Olympics. Given the amount of visitors that flow through Munich on any given day, not to mention annually, the difficulty is composing your image. The difficulty arises when one realizes that just about every conceivable way of showing the park and Zentrum has most likely been shot. Add the featureless sky, and you’re destined for disappointment.
Walking around the lake and park presented some wonderful shots, some of which I took. The problem was in trying to make an image that was different from all the cookie cutter see and shoot snapshots you see everywhere. We all see the same shots and most of take them. Without ever moving around or seeing with a slightly different point of view, we cut our cookie with our neighbor’s dime store mold.
Stopping to view the flowers and see if I could work them into a shot, I was presented with this view. I knew this shot would give my cookie a life of its own, I metered the flowers at about 500 c/ft2, or about 1 ½ stops brighter than the sky. Setting my camera to f/11 at 1/60 gave me about M+3 on the flowers and M+2ish on the sky. It also allowed the trees and building detail to come through and hold their values quite well. I edited the shot for N-1, giving a nice separation to the sky and flower values, while allowing the trees to retain a large amount of color. Shooting slower allowed some nice DOF softening at the building and trees, without detracting from their form or impact.
This image gives me, what I feel is a departure from the everyday scenes of the place, without removing the ability to tell where it was taken, and at the same time departs slightly from a literal rendering of the scene by placing the values where I visualized them. Visualizing is an important part of any image-creating endeavor, and must be practiced. This little exercise allowed me to improve my skills while on a family outing.
This week's exercise is to visualize a shot of something mundane; creating a scene that you can take ownership of with pride. See the scene as you want to show it, think through the steps to make it a reality, and then make the shot. Practice this, shoot for your vision, and exercise your creativity, you’ll love what starts happening. You’ll love your creations that stand apart from every other shot of the same thing.
I’m looking forward to seeing your results and hearing from you. Get the comments, thoughts, and questions coming. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
I hope you’ve had a chance to explore the new layout. By adding our links to another page, we’re able to expand them without limit and improve on the resources we can present. I’m currently working on an advanced section, covering metering, lighting, and other things beyond the basics.
This past weekend provided some excellent opportunities to make some photos and spend some time relaxing. I trust everyone made their shots and got their chill on, as it were.
Here’s what I’m looking at from for future posts. Beginners and Basics, Advanced Concepts and Techniques, Q and A, Composition, both elements and advanced, Reviews, and of course, continuing with our ride along shots and other items. I’d love to hear from everyone out there, if you have a suggestion, idea, or question, let us know through our Facebook link.
I’m going to close this post today with the following photo, made Saturday in Munich. Ride along with me, as we explore the shot as laid out.
Olympiazentrum in Munich.
As you can see, this was taken at Olympia Zentrum, the compound built for the 1972 Munich Olympics. Given the amount of visitors that flow through Munich on any given day, not to mention annually, the difficulty is composing your image. The difficulty arises when one realizes that just about every conceivable way of showing the park and Zentrum has most likely been shot. Add the featureless sky, and you’re destined for disappointment.
Walking around the lake and park presented some wonderful shots, some of which I took. The problem was in trying to make an image that was different from all the cookie cutter see and shoot snapshots you see everywhere. We all see the same shots and most of take them. Without ever moving around or seeing with a slightly different point of view, we cut our cookie with our neighbor’s dime store mold.
Stopping to view the flowers and see if I could work them into a shot, I was presented with this view. I knew this shot would give my cookie a life of its own, I metered the flowers at about 500 c/ft2, or about 1 ½ stops brighter than the sky. Setting my camera to f/11 at 1/60 gave me about M+3 on the flowers and M+2ish on the sky. It also allowed the trees and building detail to come through and hold their values quite well. I edited the shot for N-1, giving a nice separation to the sky and flower values, while allowing the trees to retain a large amount of color. Shooting slower allowed some nice DOF softening at the building and trees, without detracting from their form or impact.
This image gives me, what I feel is a departure from the everyday scenes of the place, without removing the ability to tell where it was taken, and at the same time departs slightly from a literal rendering of the scene by placing the values where I visualized them. Visualizing is an important part of any image-creating endeavor, and must be practiced. This little exercise allowed me to improve my skills while on a family outing.
This week's exercise is to visualize a shot of something mundane; creating a scene that you can take ownership of with pride. See the scene as you want to show it, think through the steps to make it a reality, and then make the shot. Practice this, shoot for your vision, and exercise your creativity, you’ll love what starts happening. You’ll love your creations that stand apart from every other shot of the same thing.
I’m looking forward to seeing your results and hearing from you. Get the comments, thoughts, and questions coming. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Monday, May 14, 2012
Color Balance and Exposure
Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! After a chilly weekend and a wonderful Mother’s Day with the family, it’s time to get back to the regularities of life, which includes plenty of time behind the lens. Let’s hope a nice week present Hohenfels with some great photo ops and we have our cameras ready!
Today we’ll discuss a little bit about color, color balance, and the impact they have on exposure. We most often see the impact when shooting B&W, but in today’s digital age, we see it more and more. So let’s get started.
Most of today’s sensors seem biased toward the red. When you decrease the amount of red in the scene, you decrease your overall exposure. Over the course of editing photos and correcting color balance, you’ll start noting that decreasing the color temperature toward 4000K or lower a decrease in brightness generally occurs. This is especially true when using redder lights or in daylight shots. This can be clearly seen in the following series of images. All the settings are identical, except the color balance, which was set for to display this.
Top row L-R; no color balance, 3600K, 8700K Second row; click for the flag, click for the clouds. Notice the apparent changes in both exposure level and contrast.
Color balance also affects your exposure for black and white shots, even digital ones. You can see this in the shots below.
Here we see the impact of color balance on black and white. The left is set for about 2700K and the right is 7000k.
By adjusting your color balance, you can correct your lighting to match what it was during your shooting. Doing this digitally without balancing your lighting through the proper application of color matching gels or matching your light sources can lead to issues that seem insurmountable, and may well be.
The best method to create proper color balance is to use a white target made for color balancing photographs and setting up a profile for that lighting situation. When you’re shooting a gathering for instance, set your custom white balance using the white target in the actual lighting conditions that you’ll be shooting in. This will enable you to have your white properly balanced, and enable batch white balancing. When shooting RAW this is the preferred method, as it can easily be changed should the results not be to your taste. Another method is to shoot a white balance shot as before, then only apply it where needed during RAW conversion. Of course, in situations like gatherings and events, I’ve found the best results to be obtained by shooting a white balance shot for each direction I’ll be photographing and applying them based on the shots. You usually get better results in mixed lighting this way.
When taking your white shots, make sure to frame the white card so that as much white is showing as possible. I find keeping some of the scene as reference helps when doing multiple white balance shots, so that I can remember which direction the shots were made. You can also use an 18% gray exposure target card, as long as there is no color in the card itself other than gray. Often times, the dyes used can lead to odd colorcasts. This is also true for white cards of lower quality. I used one once that showed up green on all the test shots I made. The actual shots would have been wasted if I had been shooting JPG and not RAW.
All this leads to this week’s exercise. Set your camera to monochrome and shoot a series of shots in different lighting. When you import the RAW files to your favorite converter, adjust your color temperature and see how it influences your exposure levels. Then try to apply several monochrome color filters and see the changes. Then set your picture style to one of the color modes and change your color temperature. You will see in all the cases, your exposure will change over different parts of the scene. Remember how you affect the scene, and when you’re out shooting apply that knowledge to your exposures. You’ll see things different and improve your work!
Time to get out and do some shooting, I hope you’ll be out today getting your shots in, too! Make some for us and share the wealth!
I’m looking forward to seeing your results and hearing from you. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Today we’ll discuss a little bit about color, color balance, and the impact they have on exposure. We most often see the impact when shooting B&W, but in today’s digital age, we see it more and more. So let’s get started.
Most of today’s sensors seem biased toward the red. When you decrease the amount of red in the scene, you decrease your overall exposure. Over the course of editing photos and correcting color balance, you’ll start noting that decreasing the color temperature toward 4000K or lower a decrease in brightness generally occurs. This is especially true when using redder lights or in daylight shots. This can be clearly seen in the following series of images. All the settings are identical, except the color balance, which was set for to display this.
Top row L-R; no color balance, 3600K, 8700K Second row; click for the flag, click for the clouds. Notice the apparent changes in both exposure level and contrast.
Color balance also affects your exposure for black and white shots, even digital ones. You can see this in the shots below.
Here we see the impact of color balance on black and white. The left is set for about 2700K and the right is 7000k.
By adjusting your color balance, you can correct your lighting to match what it was during your shooting. Doing this digitally without balancing your lighting through the proper application of color matching gels or matching your light sources can lead to issues that seem insurmountable, and may well be.
The best method to create proper color balance is to use a white target made for color balancing photographs and setting up a profile for that lighting situation. When you’re shooting a gathering for instance, set your custom white balance using the white target in the actual lighting conditions that you’ll be shooting in. This will enable you to have your white properly balanced, and enable batch white balancing. When shooting RAW this is the preferred method, as it can easily be changed should the results not be to your taste. Another method is to shoot a white balance shot as before, then only apply it where needed during RAW conversion. Of course, in situations like gatherings and events, I’ve found the best results to be obtained by shooting a white balance shot for each direction I’ll be photographing and applying them based on the shots. You usually get better results in mixed lighting this way.
When taking your white shots, make sure to frame the white card so that as much white is showing as possible. I find keeping some of the scene as reference helps when doing multiple white balance shots, so that I can remember which direction the shots were made. You can also use an 18% gray exposure target card, as long as there is no color in the card itself other than gray. Often times, the dyes used can lead to odd colorcasts. This is also true for white cards of lower quality. I used one once that showed up green on all the test shots I made. The actual shots would have been wasted if I had been shooting JPG and not RAW.
All this leads to this week’s exercise. Set your camera to monochrome and shoot a series of shots in different lighting. When you import the RAW files to your favorite converter, adjust your color temperature and see how it influences your exposure levels. Then try to apply several monochrome color filters and see the changes. Then set your picture style to one of the color modes and change your color temperature. You will see in all the cases, your exposure will change over different parts of the scene. Remember how you affect the scene, and when you’re out shooting apply that knowledge to your exposures. You’ll see things different and improve your work!
Time to get out and do some shooting, I hope you’ll be out today getting your shots in, too! Make some for us and share the wealth!
I’m looking forward to seeing your results and hearing from you. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Thursday, May 10, 2012
Luminance Values and Exposure
Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Spring, being upon us here in Hohenfels, is ripe with opportunities for our craft. Looking around, the trees are bright and clean, the flowers are bursting with color, and the Germany is waking up to a wonderful summer ahead.
Today’s post, delayed by unfortunate occurrences, is about luminance values, and how we can record, refer to, and use those values to improve our image. There will be some math here, but nothing major.
The first thing we need to discuss is the exposure formula. Ansel Adams described it as being the reciprocal of the luminance at a speeds key stop. The key stop for any speed is the square root of the speed. Here is a list of most speed/stop combinations.
Speed Key Stop
100 10
125 11
160 12
250 16
320 17
400 20
480/500 22
620 25
800 28
1000 32
I began the table at ISO 100 and ended at ISO 1000. ISO 100 is the lowest most consumer cameras go, and f/32 is about as high as most consumer lenses get today.
By setting your camera to any of the pairs in the table, you can read the luminance of your metered object, measured in candles/square foot, or c/ft2. For instance at ISO 125, f/11, metering 1/125, then the luminance value is 125 c/ft2. If your meter shows 30 seconds, then the luminance is 1/30 c/ft2. That will put you at 18%, or neutral gray reference values. This is what I refer to as M, or an M exposure.
When photographing normal scenes, we often encounter a scale of values that for any given exposure will run from approximately M-5 and lower to M+5 or higher. By learning to look at luminance values as described above, you learn to tame that range, creating an image that will make you justifiably proud.
An example of exposing for your luminance reading is when you meter the clear sky; you should read about f/11, ISO125, 1/300. This will put your sky into the range of 18% reflectance. We know that a clear Northern sky should fall about M+1, which means we should expose for the sky at f/11, ISO125, 1/150. Of course, this goes back to place and fall exposures. You must decide the key elements within your scene and where they should be placed. Once this exposure and placement is determined, all other values fall where their luminance levels impact your sensor. Knowing these values will help you determine where you wish to place elements and where your remaining elements will fall.
Even metering clouds, you will find a range of luminance values that may run from 200 c/ft2 to 1000 c/ft2. By meter the brightest part, 1000 c/ft2, then adding 3 stops, you bring your 200 c/ft2 up to nearly M+1 ½ in the exposure range, which is slightly brighter than the surrounding blue sky, and significantly darker than the brights in the clouds. Your brights will print out with slight tonal variations, and darker areas will have adequate or better textural ranges. You also bring areas metering at 50 c/ft2 up to the equivalent exposure of 400 c/ft2. These equivalent values are in relation to your original metering from the bright part of the clouds.
Recording your luminance values across the range of your scene will help you learn to recognize values, and expose with more confidence. It will also help in editing your images and preparing them for either printing or display. I would suggest metering across the range of M-4 to M+4 after determining your priorities, and noting the results. Even if you’re shooting at some combination not listed above, take the luminance readings using a combination. After reading the values, switch to your desired settings, compose, and make your image. Values for M+ and M- can be extrapolated by halving or doubling the values obtained with your meter. This is less accurate, but still of considerable value in perfecting your images.
Another great advantage of knowing your luminance and place values, is the ability to tell anyone about your exposure without giving the ISO, f/stop, EI, shutter speed, and so on. Tell them you metered this at 250 c/ft2, and gave M+1 to get the exposure where you wanted it. Regardless of your settings, they will know that to get that exposure from 250 c/ft2, then they give M+1 at whatever aperture and speed they desire, for instance ISO 125, f/8, 1/250 or ISO 400, f/5.6, 1/1600. Both will give the same results, and use the same values, 250 c/ft2 +1 stop, and make exposing a scene more consistent. It’s also useful when referring to edits performed. Taking the last example, you may have shot at M+1, and then edited it to M to decrease contrast. In this case, you can say this was shot at 250 c/ft2 +1 stop, then edited to M for the final effect. This will help others understand and help you remember your shots without having to know every little bit of detail.
There are other ways of expressing luminance, for instance EV or c/m2, or lumens, and as long as you find a consistent method of evaluating and expressing that exposure, your images will be consistent with your vision. Don’t get hung up on what I use, try it and if it doesn’t work, try something else. You’ll still have a working system, and you’ll still be enjoying what we love to do!
Time to get out and do some shooting, I hope you’ll be out today getting your shots in, too!
I’m looking forward to seeing your results and hearing from you. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Today’s post, delayed by unfortunate occurrences, is about luminance values, and how we can record, refer to, and use those values to improve our image. There will be some math here, but nothing major.
The first thing we need to discuss is the exposure formula. Ansel Adams described it as being the reciprocal of the luminance at a speeds key stop. The key stop for any speed is the square root of the speed. Here is a list of most speed/stop combinations.
Speed Key Stop
100 10
125 11
160 12
250 16
320 17
400 20
480/500 22
620 25
800 28
1000 32
I began the table at ISO 100 and ended at ISO 1000. ISO 100 is the lowest most consumer cameras go, and f/32 is about as high as most consumer lenses get today.
By setting your camera to any of the pairs in the table, you can read the luminance of your metered object, measured in candles/square foot, or c/ft2. For instance at ISO 125, f/11, metering 1/125, then the luminance value is 125 c/ft2. If your meter shows 30 seconds, then the luminance is 1/30 c/ft2. That will put you at 18%, or neutral gray reference values. This is what I refer to as M, or an M exposure.
When photographing normal scenes, we often encounter a scale of values that for any given exposure will run from approximately M-5 and lower to M+5 or higher. By learning to look at luminance values as described above, you learn to tame that range, creating an image that will make you justifiably proud.
An example of exposing for your luminance reading is when you meter the clear sky; you should read about f/11, ISO125, 1/300. This will put your sky into the range of 18% reflectance. We know that a clear Northern sky should fall about M+1, which means we should expose for the sky at f/11, ISO125, 1/150. Of course, this goes back to place and fall exposures. You must decide the key elements within your scene and where they should be placed. Once this exposure and placement is determined, all other values fall where their luminance levels impact your sensor. Knowing these values will help you determine where you wish to place elements and where your remaining elements will fall.
Even metering clouds, you will find a range of luminance values that may run from 200 c/ft2 to 1000 c/ft2. By meter the brightest part, 1000 c/ft2, then adding 3 stops, you bring your 200 c/ft2 up to nearly M+1 ½ in the exposure range, which is slightly brighter than the surrounding blue sky, and significantly darker than the brights in the clouds. Your brights will print out with slight tonal variations, and darker areas will have adequate or better textural ranges. You also bring areas metering at 50 c/ft2 up to the equivalent exposure of 400 c/ft2. These equivalent values are in relation to your original metering from the bright part of the clouds.
Recording your luminance values across the range of your scene will help you learn to recognize values, and expose with more confidence. It will also help in editing your images and preparing them for either printing or display. I would suggest metering across the range of M-4 to M+4 after determining your priorities, and noting the results. Even if you’re shooting at some combination not listed above, take the luminance readings using a combination. After reading the values, switch to your desired settings, compose, and make your image. Values for M+ and M- can be extrapolated by halving or doubling the values obtained with your meter. This is less accurate, but still of considerable value in perfecting your images.
Another great advantage of knowing your luminance and place values, is the ability to tell anyone about your exposure without giving the ISO, f/stop, EI, shutter speed, and so on. Tell them you metered this at 250 c/ft2, and gave M+1 to get the exposure where you wanted it. Regardless of your settings, they will know that to get that exposure from 250 c/ft2, then they give M+1 at whatever aperture and speed they desire, for instance ISO 125, f/8, 1/250 or ISO 400, f/5.6, 1/1600. Both will give the same results, and use the same values, 250 c/ft2 +1 stop, and make exposing a scene more consistent. It’s also useful when referring to edits performed. Taking the last example, you may have shot at M+1, and then edited it to M to decrease contrast. In this case, you can say this was shot at 250 c/ft2 +1 stop, then edited to M for the final effect. This will help others understand and help you remember your shots without having to know every little bit of detail.
There are other ways of expressing luminance, for instance EV or c/m2, or lumens, and as long as you find a consistent method of evaluating and expressing that exposure, your images will be consistent with your vision. Don’t get hung up on what I use, try it and if it doesn’t work, try something else. You’ll still have a working system, and you’ll still be enjoying what we love to do!
Time to get out and do some shooting, I hope you’ll be out today getting your shots in, too!
I’m looking forward to seeing your results and hearing from you. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Friday, May 4, 2012
Tech Talk: Rating Your Sensor
Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! WOW! The annual Hohenfels Volksfest was a great time and the weather was perfect. Now the clouds are puffing up some, and that makes for great outdoor photos that include the sky!
Today we’re going to introduce rating and EI.
Your camera has a range of ISOs you can choose from, most likely running from ISO100 to ISO3200 in third stop increments. Camera and film manufacturers used the International Standards Organization methods to set the speed, or ISO, of your sensor or film. They generally are set to favor overexposure, as underexposure is harder to correct. Therefore, in test conditions ISO 100 performs at ISO 80-100 to get you exposed at the general target for the contrast and exposure standards set by the organization. This used to be referred to as a film’s “box speed.” For digital work, I’ve come to think of it as “nominal.” Therefore, when I say I shot it at ISO 125, that’s what I was set and exposed for.
The ISO recognized that most scenes deviated from test conditions, as did developing or processing. A film may be rated at ISO 100, when developed in a certain developer for a specific time, but not for any other combination. Film shooters would “rate” their film at different speeds for their methods, including exposure and development controls. For instance, some would shoot FP4+, which is ISO125 in Ilford’s ID11 developer, rated at EI80 developed in Kodak D-76 for their preferred method of exposing and developing a standard shot.
EI, or “exposure index,” is what you rate your film at for your methods, and usually refers to speed rating assigned that’s different from the film's actual speed. Generally, when you shoot with your digital SLR, you shoot maybe at ISO 100, and edit it in your manufacturer’s provided application and get decent results. You are shooting and making your shot at nominal speed, or box speed with film.
You may find that in high contrast scenes at nominal speed, you are getting shadows that are clipped to black and whites that are blown and have no detail. In that case, it’s time to change your EI, or rate your speed different. To do this correctly, you should test your camera, and we’re going to cover the procedures to do that for YOUR best results. Since this test is based on your equipment, metering, and editing, someone else will get different results using the same equipment. This test is based on your style and methods, which others may not follow. Keep that in mind when “rating” your gear, you can recommend your “rating” to others with the same camera, they will most likely appreciate the information, but each “rating” is subjective, and will work best in your hands.
This testing becomes especially important when shooting at extremes of lighting. In very low light, like that in most old buildings, noise is a real concern when trying to increase your image brightness during editing, and in bright daylight lit landscapes skies and clouds can become just blotches of white without any detail.
The procedures for setting your EI involved a gray card, meter, and your camera. You should be set up for this in light conditions that match your intended shooting conditions to effectively use this method.
Step 1, set up your gray card in lighting that matches your shooting conditions. Step 2, set your desired ISO reading on your camera, and select RAW mode. Step 3; set your camera to f/8 or f/11 and AV mode. Step 4, meter your gray card, use spot metering and fill as much of the frame as possible with the gray card. Note the shutter speed. Step 4, set your camera to manual mode, and enter the shutter speed metered in step3, which should give you an 18% gray image. Step 5: compose your test shot. You can pull back some, including other elements. I have a test screen that includes black and white pieces and collapses nicely into a camera bag, and prefer to use that to check contrast ranges while doing this test. Step 6, take the following series of shots- at the metered reading obtained previously, -1/3 stop, -2/3 stop, -1 stop, +1/3 stop, +2/3 stop, and +1 stop. Step 7, load the images onto your computer. Then open your image editing application. Step 8, Open each image in turn, and find the one that is MOST CLOSELY identical to the gray card in exposure for your set up. Make sure to perform absolutely no adjustments to the images, as we are looking for the most closely identical image. Take note of the settings used for this shot. Step 9, this is your EI for that type of scene with that ISO selected. For example if –1/3 stop produced the best rendition for ISO100, then your EI would be 125 or EI125. You will effectively be rating your ISO100 shots at 125, and removing 1/3 stop on all your shots in those conditions. To accomplish this, when shooting at ISO100 simply remove 1/3 stop exposure, either by increasing your shutter speed 1/3 stop or closing down your aperture 1/3 stop.
Rating your sensor or speed before shooting can save a lot of time editing and the heartbreak of a shot that doesn’t live up to your expectations. It’s not perfect, and varies based up taste, style, and personal preference, but it will bring you closer to achieving your vision. It’s definitely something to try in conjunction with this week’s exercise on contrast and contrast control. Combine it with M+ and M- exposure placement for even better results. By exposing properly, you can keep your contrast in the desired range, and make it easier to achieve your vision in your final processing stage.
For those interested in more information about film speed, Wikipedia has a great article. It includes formulae and details about how box speed and nominal are attained.
I’m looking forward to seeing your results and hearing from you. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Today we’re going to introduce rating and EI.
Your camera has a range of ISOs you can choose from, most likely running from ISO100 to ISO3200 in third stop increments. Camera and film manufacturers used the International Standards Organization methods to set the speed, or ISO, of your sensor or film. They generally are set to favor overexposure, as underexposure is harder to correct. Therefore, in test conditions ISO 100 performs at ISO 80-100 to get you exposed at the general target for the contrast and exposure standards set by the organization. This used to be referred to as a film’s “box speed.” For digital work, I’ve come to think of it as “nominal.” Therefore, when I say I shot it at ISO 125, that’s what I was set and exposed for.
The ISO recognized that most scenes deviated from test conditions, as did developing or processing. A film may be rated at ISO 100, when developed in a certain developer for a specific time, but not for any other combination. Film shooters would “rate” their film at different speeds for their methods, including exposure and development controls. For instance, some would shoot FP4+, which is ISO125 in Ilford’s ID11 developer, rated at EI80 developed in Kodak D-76 for their preferred method of exposing and developing a standard shot.
EI, or “exposure index,” is what you rate your film at for your methods, and usually refers to speed rating assigned that’s different from the film's actual speed. Generally, when you shoot with your digital SLR, you shoot maybe at ISO 100, and edit it in your manufacturer’s provided application and get decent results. You are shooting and making your shot at nominal speed, or box speed with film.
You may find that in high contrast scenes at nominal speed, you are getting shadows that are clipped to black and whites that are blown and have no detail. In that case, it’s time to change your EI, or rate your speed different. To do this correctly, you should test your camera, and we’re going to cover the procedures to do that for YOUR best results. Since this test is based on your equipment, metering, and editing, someone else will get different results using the same equipment. This test is based on your style and methods, which others may not follow. Keep that in mind when “rating” your gear, you can recommend your “rating” to others with the same camera, they will most likely appreciate the information, but each “rating” is subjective, and will work best in your hands.
This testing becomes especially important when shooting at extremes of lighting. In very low light, like that in most old buildings, noise is a real concern when trying to increase your image brightness during editing, and in bright daylight lit landscapes skies and clouds can become just blotches of white without any detail.
The procedures for setting your EI involved a gray card, meter, and your camera. You should be set up for this in light conditions that match your intended shooting conditions to effectively use this method.
Step 1, set up your gray card in lighting that matches your shooting conditions. Step 2, set your desired ISO reading on your camera, and select RAW mode. Step 3; set your camera to f/8 or f/11 and AV mode. Step 4, meter your gray card, use spot metering and fill as much of the frame as possible with the gray card. Note the shutter speed. Step 4, set your camera to manual mode, and enter the shutter speed metered in step3, which should give you an 18% gray image. Step 5: compose your test shot. You can pull back some, including other elements. I have a test screen that includes black and white pieces and collapses nicely into a camera bag, and prefer to use that to check contrast ranges while doing this test. Step 6, take the following series of shots- at the metered reading obtained previously, -1/3 stop, -2/3 stop, -1 stop, +1/3 stop, +2/3 stop, and +1 stop. Step 7, load the images onto your computer. Then open your image editing application. Step 8, Open each image in turn, and find the one that is MOST CLOSELY identical to the gray card in exposure for your set up. Make sure to perform absolutely no adjustments to the images, as we are looking for the most closely identical image. Take note of the settings used for this shot. Step 9, this is your EI for that type of scene with that ISO selected. For example if –1/3 stop produced the best rendition for ISO100, then your EI would be 125 or EI125. You will effectively be rating your ISO100 shots at 125, and removing 1/3 stop on all your shots in those conditions. To accomplish this, when shooting at ISO100 simply remove 1/3 stop exposure, either by increasing your shutter speed 1/3 stop or closing down your aperture 1/3 stop.
Rating your sensor or speed before shooting can save a lot of time editing and the heartbreak of a shot that doesn’t live up to your expectations. It’s not perfect, and varies based up taste, style, and personal preference, but it will bring you closer to achieving your vision. It’s definitely something to try in conjunction with this week’s exercise on contrast and contrast control. Combine it with M+ and M- exposure placement for even better results. By exposing properly, you can keep your contrast in the desired range, and make it easier to achieve your vision in your final processing stage.
For those interested in more information about film speed, Wikipedia has a great article. It includes formulae and details about how box speed and nominal are attained.
I’m looking forward to seeing your results and hearing from you. Let me know what you think and how you’re using your camera! Share your thoughts here or at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
Tuesday, May 1, 2012
Another Exercise...
Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Hohenfels, basking in the warmth and sun of spring, has really enjoyed having the annual German American Volksfest. I hope the Hohenfels Volks has, too, with all the opportunities to get and make some great shots!
In keeping with our last post, I thought I’d share a photo from Saturday’s fireworks, and then move on to another exercise.
f/22, ISO 125, 16 seconds, Bulb mode
Fireworks from the Volks fest
I shot from the parking area, including the windsock in the image, to create some context. Notice the fest tent in the lower left to give a sense of scale. I shot this at f/22 to minimize the impact of the Ferris wheel and to create some nice starbursts with the lighting along the bottom. The timing on this shot was quite lucky, as the combined effects create a flower like appearance of the fireworks. The white “dot” below and to the right of the larger burst was the only star visible at that time. I liked having it there, but could have cloned it out. Things like that are a matter of taste.
On to our exercise, we’re going to look at taming the relationship between highlights and shadows. One way to do this is through a combination of metering and exposure. Shoot scenes with a relatively high range of contrasts, but meter for the desired range. Should the highlights be the most important meter for them, and likewise for the shadows or midtones.
When shooting these shots, keep in mind controls you can use for bringing your images into line with your intention. For instance, a high contrast scene can be tamed slightly using an inverted S curves adjustment, and lowering the contrast. Remember, less is more, as applying too much of only one adjustment can leave the scene looking like, in the words of Ansel Adams, “chalk and charcoal.”
There are ways to increase contrast and lower it at the same time. We’ll look at some in a post later this week, but they include things like toning and intensification.
f/11, ISO 125, 1/60, metered for the highlights on the clouds and exposed at M+3
Stormy looking clouds over the fest. Edited for an old time semi-selenium toning and intensification.
Get out, get shooting, and enjoy the weather while it lasts!
Don’t forget to post any of your images you’d like to see here at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
In keeping with our last post, I thought I’d share a photo from Saturday’s fireworks, and then move on to another exercise.
f/22, ISO 125, 16 seconds, Bulb mode
Fireworks from the Volks fest
I shot from the parking area, including the windsock in the image, to create some context. Notice the fest tent in the lower left to give a sense of scale. I shot this at f/22 to minimize the impact of the Ferris wheel and to create some nice starbursts with the lighting along the bottom. The timing on this shot was quite lucky, as the combined effects create a flower like appearance of the fireworks. The white “dot” below and to the right of the larger burst was the only star visible at that time. I liked having it there, but could have cloned it out. Things like that are a matter of taste.
On to our exercise, we’re going to look at taming the relationship between highlights and shadows. One way to do this is through a combination of metering and exposure. Shoot scenes with a relatively high range of contrasts, but meter for the desired range. Should the highlights be the most important meter for them, and likewise for the shadows or midtones.
When shooting these shots, keep in mind controls you can use for bringing your images into line with your intention. For instance, a high contrast scene can be tamed slightly using an inverted S curves adjustment, and lowering the contrast. Remember, less is more, as applying too much of only one adjustment can leave the scene looking like, in the words of Ansel Adams, “chalk and charcoal.”
There are ways to increase contrast and lower it at the same time. We’ll look at some in a post later this week, but they include things like toning and intensification.
f/11, ISO 125, 1/60, metered for the highlights on the clouds and exposed at M+3
Stormy looking clouds over the fest. Edited for an old time semi-selenium toning and intensification.
Get out, get shooting, and enjoy the weather while it lasts!
Don’t forget to post any of your images you’d like to see here at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too! Don't forget, we're on Google+, too!
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