Ride Along Shot: High...

Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Welcoming Tuesday, Hohenfels finds a nice day breaking out and greeting us back.

Let’s visit Regensburg for another ride along shot. This time we’re going to look at a shot taken on film in the old part of town.

Here’s the image.

ISO 100 Agfa APX100, f/8, 1/50, 50mm
A shop window in Regensburg's old town.

This was taken outside one of the many little shops lining the square, and not far from the Dom, or cathedral. I was immediately attracted to the material, old boxes, wreaths, and some cool roses. Throw in the bottles and glassware in the window, and it really seemed like a “must have” shot.

Metering from the white portion in the bottom right window gave too little exposure, so I shot at M+3 and developed for N. This left white zone to about M+3 and leaves a nice tonal range. This also gives us a nice high key image, with a very suitable contrast, and detail in the brightest parts. The reflections in the windows could have been removed with a CP filter, but I would lose the high key effect of the light reflecting around the scene.

The meter gave me f/16 at 1/100. I think this was shot on Agfa APX100 film. I shot with a 50mm f/1.8 prime, as I did the entire day. The final exposure was f/8 and 1/50, with an ISO of 100. I didn’t want to go slower, as the old cameras had no IS, and any wider would have left the DOF inadequate to express what I had envisioned. The sun was out, it was mid-day, and the weather had warmed up a little that day. It was still snowing back in Hohenfels, which was a bit surprising as I got off the train.

After scanning the negative, editing was most certainly required. The sharpness was quite nearly gone, the contrast had come down, and the whites were nearly blown. By applying curves in an inverse S and adjusting the levels to bring down the shadows, and raise the midtones and highlights, I was nearly complete. The next step was to reduce noise and apply an unsharp mask at about 3px radius, 90 strength, and 2 clipping.

The final image grew on me. At first, being satisfied with the image, it was ok. After editing and revisiting the image several times, I realize it had become something I really liked. It showed that the system of metering for the highlights when you plan an image to be presented digitally, can lead to some really nice results.

By exposing on the plus side, it brought out some detail in the shadows, allowing just enough to bring the eye to them in the middle of the brights. Our eyes are generally drawn to the brightest part of a scene first, which is why we often keep our subject 1/3 to 1 stop brighter that the surrounding. In cases like this, it sets our darks apart and brings focus to the play between shadow and light.

I hope I haven’t bored you too much! Enjoy the rest of a lovely evening, maybe using this time to get some blue or golden hour shots in. Take care and keep shooting.

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!

Reviewing the Basics

Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Brrr. That’s our word of the day!

Today we’re going to review some of the basics of photography and exposure. This can all be found on our Introduction to Photography page. We should all have a good idea of this stuff, but it always helps to refresh the cup, so to speak.

First, we’ll address our exposure triangle. The triangle consists of 1- ISO or film speed, 2- shutter speed, and 3- aperture. To change exposure, you change any side of the triangle. To keep the same exposure, you have to change at least 2 sides. For instance, we set up on a sunny day at ISO 100, f/16, and 1/100. According to the “sunny 16 rule,” we’re good to go. But we want less DOF, so we need to increase our aperture. We go to f/4 to give us a shallow focus. If we don’t change another side of our triangle, we overexpose and create a mess. We have a 4-stop increase in the amount of light coming in, so we need a four-stop increase in shutter speed or 4-stop decrease in ISO. Since we can’t bring our ISO lower, we need to change our shutter speed to 1/1600. At 1/1600 at f/4, that gives us the same as 1/100 at f/16. If we want to increase our exposure, we can change any 1 side and either decrease our exposure or increase it depending on our new settings. For instance we want to increase our exposure on ISO 100, f/16, 1/100 2 stops, so increasing our aperture to f/8, decreasing our shutter speed to 1/25, or increasing our ISO to 400 will do just that. Remember, when we meter something, or a scene, the meter gives us the exposure for 18% gray, which is zone 5. Knowing this allows us to place the item we meter into different zones or exposure levels.

Next up, we’ll look quickly at depth of field, or DOF. This is a product of our focal length and aperture. The longer our lens’s focal length is, the shallower our DOF. The wider our aperture is, the shallower our DOF. This can be a good way to remove or minimize distractions. A 100mm lens at f/16 has about the same DOF as a 50mm lens at f/4. Focused at 10 feet, both give a DOF running from about 9.17 to 11 feet. Seeing that, you can deduce that a shorter lens has a wider DOF.

Remember, these 2 topics we’ve reviewed go together. By adjusting your aperture for a shallower DOF, you’ll have to change something else to maintain your exposure. If you wish to move into a new zone, you’ll change your DOF if you use your aperture to move zones.

We’ll review composition and inspiration in our next talk. Remember to vote and get your pics in early. I hope you’ll all participate in this week’s theme, solitude. We’re aiming for more votes for our theme, so get involved and let’s enjoy the journey together!

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 foget, we're on Google+, too!

Tech Talk: Hyperfocal Distance

Greetings, volks. Welcome to Hohenfels Volks, THE place for our place! Today we’re going to learn about hyperfocal distance.

What is hyperfocal distance? It’s the distance you focus your lens for to have a maximum DOF. When you focus at this distance, everything from about half that distance to infinity is in acceptably sharp focus. To accomplish this and to define acceptably sharp focus you need to know your circle of confusion (COC.) COC is the largest size that a point or spot can be without appearing out of focus. For an APS-C size sensor, which most of us have, that number is .019. The smaller your COC, the greater your sharpness. Although, for different sensors and films that number is different. For 6cmx9cm film, it’s generally accepted to be .07, and for 35mm or full frame sensors, it’s about .03.

Things get mathematical here, so you may want your calculator. You can calculate the hyperfocal distance for a given lens and aperture using this method. Take the focal length of your lens and square it to get variable a, next take your aperture or f/stop and multiply it by the COC to get variable b. Divide a by b, and there you have your hyperfocal distance. Here’s how it looks in mathematical terms

H =F²/(f x C)

In the equation above
H = hyperfocal distance
F = focal length
f = f/stop
C = COC

As an example, your lens is 50mm, you wish to focus on something 10 meters away, use f/11, and you’re using an APS-C sensor. 50x50/(11x.019). This gives us 2500/(11x.019) or 2500/.209, and finally approximately 11.9 meters. If you focus at infinity on your lens, your DOF will run from 11.9 meters to infinity. If you focus at 11.9 meters, your DOF will run about 6 meters to infinity. By focusing at your hyperfocal distance, you can maximize your DOF in an image and get that winning shot. By using this calculation on a variety of focal lengths and f/stops, you can see why smaller apertures (bigger f-numbers) give you greater DOF.

There are 2 other ways to figure it out. Both are much easier, if you are using a higher end lens with a scale on it, you set the infinity symbol on your lens to line up on your f/stop at the far scale, then everything from the matching f/stop on the near scale to infinity will be acceptably sharp. That allows for Maximum DOF and zone focusing. The other easier way is to look it online. There are so many sites that you can find on Google just searching for hyperfocal distance, that you’ll never be at a loss. I prefer using DOF Master, as they have some great stuff there and it’s too easy. You just enter your info and away you go!

I hope this gives you some idea of how to use your focus for maximum DOF and how to get that extra bit of oomph to make your image stand out. Next time we’ll be calculating DOF, more math so keep that calculator handy!

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!

In the Zone- Zone Focusing

Greetings and welcome to Hohenfels Volks, THE place for our place. I hope you’re ready, Hohenfels, to learn about zone focusing. This is something that can make getting some of those passing moments in the can, as it were, quicker and easier.

First off, let’s explain what zone focusing is. Zone focusing is using a combination of focal length, aperture, and distance to allow for enough depth of field to make a usable print. That’s pretty straight forward, right? Well, there is more to it than that, including knowing your equipment.

Zone focus developed as a way for photographers to focus their equipment, as most older cameras had no viewfinder or way to check your focus. Many of the old time greats used zone focusing to maximize the sharpness and detail in their works. Given the nature of early lenses, high f/stops were often required to get good detail and enough DOF to be worth printing. Remember, sheets of film, and rolls, were costly to purchase, develop, and print, so lots of effort went into taking each shot. Zone focusing grew from the concept and practice of hyperfocal distance, which you use to give you the maximum DOF for each lens focal length. We’ll have more on that in another post.

The technique works best with lenses that have markings on them. A distance scale for focusing opposite an aperture scale with DOF markings as shown in the photo below works best. It’s quicker and easier. Unfortunately, most lenses today are auto-focus, and kit lenses generally don’t have such marking. Higher end lenses do have them, as do pro and manual lenses as a rule.


ISO 200, f/4.5, 1/30, 32mm
Notice the f/stops on the front of the ring. They go out from the diamond marking focal distance, to give you the range, or zone, of acceptable focus.

Referring to the image above, you can see that there is a diamond. That is the distance marker. On the focus ring, there are markers that aren’t shown, that tell you your focal distance. Line up the desired distance, then using the f/stops that radiate out from the diamond, identically on either side, determine your needed aperture and distance. The distance covered will line up with the marks for the desired aperture. It’s that simple, anything in that range will be in sharp enough focus for decent size prints, including 8x10 and 11x14 if your camera has the resolution.

If your lens has a focusing distance scale, much like Canon’s 28-135mm, you can figure out your DOF with a little legwork online. The key when using zone focus, is to turn off your auto-focus. The second factor is to shoot either Aperture Priority or Manual modes only! Any other mode nullifies your efforts!

Know your location, and what’s happening there, and you can figure the ranges you will need. Let’s say for our purposes you’re shooting in a decently lit area at ISO 400 and you need to cover 3 meters and 6 meters, with room to spare. You get you’re framing, that will give you your focal length. You know it’s decently lit and you can get by with f/5.6-f/8. Going with a 55mm focal length, as most kit lenses like to go from 18-55mm, you should be focused at 4 meters for f/5.6 and 3.5 meters for f/8, although 4 meters is adequate, and has the advantage of allowing you to switch over to f/5.6 without losing too much DOF. If your lens doesn’t have a focal distance scale, measure off 4 meters, focus your lens, and mark it. An easy tip for marking your focus, is take 2 fat rubber bands and wrap one around the zoom ring of your lens at the focal length you wish to use, then wrap the other around the focus ring. Mark the one on the zoom ring at the top, focus your camera, then make a mark that lines up with the first mark you made. As time progresses and your lens drifts over the course of events, you always have your focus marked and can return to it in a snap. Then set your aperture and you’re cooking with gas!

A great online DOF calculator that just requires your focal length, camera model, and scale used (feet or meters) is DOF Master's DOF table. They also have some great information on hyperfocal distance and some nifty little software to play with!

If your shooting with a flash, your f/stop will be dictated by the flash when you use manual flash. TTL and E-TTL are great for using flash, but to use it right, you need a sync cable that’s designed for your camera maker or line to get it off camera. You can get a good one that’s about a meter reasonably priced. Add in a Flashbender or Sto-fen to diffuse the light some, and you’re off to the races. This allows you to hand hold your flash off camera and get some directional TTL or E-TTL light in your images that just adds to the quality.

Zone focusing is great for street photography, event photography, candids, and may other things. Try it out in your works and see how it can help you! You can also use it for this week's theme, as it will allow you to appear less obtrusive when shooting work getting done!

Enjoy the rest of your day, and remember to cast your vote for next week’s theme. Get yours in to have a say! Don’t forget to get your pics posted at the Hohenfels Volks Facebook page. Of course, commenting on both Facebook and here is always appreciated, too!

Tools of the Trade- More on Lenses

Greetings, Hohenfels, welcome to Hohenfels Volks, THE place for our place. Here’s hoping today sees you starting on the downhill run of a great week!

Today it’s time to talk a little about lens attributes and traits.

We’ve already talked a little about lenses, so today we’re going to concentrate on some of the quality issues and features of your lenses. It’s a little long, for which I apologize.

One of the first things most folks need to know is that your old film lenses will work on digital cameras. They may have a crop factor, for instance 1.6X for APS-C, but if they can mount on your camera, you can use them. On the other hand, your newer digital lenses are unusable on full frame or film cameras. When you put a film lens on an APS-C sensor, the crop factor comes from the distance from the back of the lens to the sensor. The film lenses cover a larger area than the sensor; this in turn causes an apparent increase in focal length and the crop. Canon’s recent systems, the EOS cameras, use EF lenses, which have a 1.6X crop on your APS-C sensor. Their digital line of lenses for the EOS system is the EF-S line. They require no crop factor and apparent focal length is actual focal length. The reason the digital series of lenses don’t work on full frame or film cameras is due to their smaller projection of the image onto a smaller sensor. They won’t fill the frame or film, and most likely won’t even focus properly even if they could be mounted.

Another concern about your lens on zoom lenses is often the aperture. Less expensive lenses read something like 28-135 f/3.5-5.6. This is because the aperture size doesn’t change during zooming, that is the largest it can go. The area of the aperture remains constant, requiring a change in f-number. If you remember, your f-number is a ratio of focal length and aperture. It represents the focal length divided by that number, that’s why it’s written f/2, f/5.6 etc. The longer a lens is, the less light reaches the sensor. That’s why the f/number changes throughout the range of zooms. If your area doesn’t change, your f-number must. The reason for this is the cost and weight added to vary the aperture size throughout the zoom range. That doesn’t mean a constant aperture means a cheap lens, it doesn’t mean less quality, it just means less light as you zoom in.

A great feature of lenses over the past few years is the addition of IS. The affordability of technology has made it possible to use feature that used to be unavailable to the hobbyist. IS allows slower shutter speeds when enabled. Using it hand held, you can get down to about 3 stops lower that the handheld limits. The systems work by compensating for motion with motion in the opposite direction. When hand holding your shot, using proper shooting styles, with arms tucked in etc, will enable the IS to really slug it out with vibration. The most important thing to remember is turning it on for handheld, and ALWAYS turn it off for tripod shots. When on a tripod, the IS searches for motion in the lens and can cause vibration rather than reducing it. The big drawback to IS is that it uses your camera’s battery for power.

The last thing I’ll bring up for now is a quality issue. The problem is chromatic aberration or CA. This is distortion caused by different colors, or wavelengths, of light focusing at differing areas on your sensor. There are several types and names, but we’re not going into it that deep here. It often causes the purple fringing that you see along borders with bright highlights and dark shadows together. Using a smaller aperture can help mitigate this, as can a longer lens. Low dispersion glass and good coatings can combat this effectively. There seems to be many complexities involved in CA, including the types and calculations. The best practice when purchasing a lens, if possible, is to take a test shot using that lens of a high contrast area, and zoom in looking for fringing. CA can also cause blurriness in Black and White photography, so keep that in mind. You can see examples on Google to get more information and some idea of what to look for. According to the reviews I’ve read, Canon makes the most advanced software correction to mitigate CA and other distortions available. Because Canon’s EF lens system is actually all electronic, and records the information on individual lens models, Digital Photo Pro can compensate for it. Yet another advantage of shooting RAW!

Whenever you look to purchase a lens, make sure you read a variety of reviews, and look at loads of test photos taken with that lens, it could save you some headaches! If you have a lens that you favor and would like to write it up here, let me know, and I’ll get it posted for you!

Now on to other things, remember to get your votes in for next week’s theme. This week our theme is “Morning Moments.” Dazzle me with your work! Get shooting and start posting at the Hohenfels Volks Facebook page. Of course, commenting here is always welcome, too!

FOCAL LENGTH

Welcome to another post!

Our topic this time is FOCAL LENGTH, and covers more than just lens sizes.

Let’s start out with the basics; FOCAL LENGTH refers to the length of your lens, usually in millimeters. A 300mm lens is 300 millimeters, but crop factor can change the apparent FOCAL LENGTH of the lens. Crop Factor refers to sensor size on a digital camera. Most of us use cameras with an APS-C sensor, which provides a 1.6x crop factor, or 1.6 times the magnification of the lens’s FOCAL LENGTH. Unless a lens is made for the specific crop factor, for instance Canon’s EF-S lenses, crop factor must be counted to provide the correct focal length. Therefore, a 300mm lens at 1.6x crop factor has an apparent FOCAL LENGTH of 480mm. Since most of us now use the digital lenses that either came with our camera, or we purchased later, I’m not going to make too much of crop factor, that’s for another post.

A large number of folks believe that the perceived change between two FOCAL LENGTHS is caused entirely by magnification. This is actually not entirely true. When you zoom in closer, your lens covers a smaller area of the scene. It doesn’t really magnify it, just shows less in the same amount of space, although there is some magnification from the optics. If you look through a toilet paper tube and take note of what you see, then look through a paper towel tube of about the same diameter, you’ll notice this effect.

Another effect of FOCAL LENGTH, is longer FOCAL LENGTHS, compress the distance between objects in your scene, making them appear closer together. This is great for a portrait with a shallow DOF, as it can blur out and compress the background for a nice effect. It’s something to pay attention to, as the effect can make a great picture look somewhat flat and plain.

For more the rest of this article about FOCAL LENGTH, check out our Intro to Photography page, which contains our full intro series posts so far. And for a great article about the effects of FOCAL LENGTH, check out Photo Tuts+. You can also get into the maths of it at Wikipedia!

I hope this article will be useful on your photographic journey. The knowledge really helped me! Enjoy the weekend folks, and keep your eyes open for more articles, tips, and Hohenfels Volks photo goodness!