Category:Macro Photography
From ReefPedia
Excuse the mess. This page is very much a work in progress.
Getting up-close and personal
Macro photography in aquaria
You’ve probably seen some absolutely stunning close-up shots of corals. Sometimes they’re so close up as to reduce the flesh of the coral to a pattern. Or you may see detail in the face of a hermit crab that you’ve never seen before. One of the great pleasures of macro photography, as a matter of fact, is that it offers a different perspective. Closer than you’ve ever thought to look, quite possibly closer than the eye can focus.
Macro photography is indeed its own discipline, and one that mixes quite well with aquarium photography, often with mind-blowing results.
What’s different with macro?
It takes a special kind of lens.
It takes patience.
It takes extremely good focusing skills.
It takes a whole lot of depth-of-field.
Sometimes it takes special equipment.
Macro rails/sliders
Extension tubes
Reversed lenses
Getting “closer”
First of all, when working with macro photography, there are really two different ways to interpret the word “closer”, and each meaning needs to be addressed differently.
To again form a common language and avoid confusion, we should talk about the subject’s size in the viewfinder as “magnification.” Magnification simply means how big a certain object appears in your image. If you want an entire leaf of a plant or algae in the image, more mangification is required than if you want a branch in the image.
First scenario- you point the camera at the tank and zoom all the way in. Looking through the viewfinder or LD screen, your subject just isn’t big enough. You want more magnification. Oftentimes, people will simply say they want to get “closer,” which I believe is the cause of much confusion and the catalyst for the purchase of inappropriate accessories.
“Closer” can mean more telephoto focal length. In other words, “more zoom.” Standing in the same place, if you could just zoom in a little bit more, you’d be in business.
“Closer” can also mean moving the camera physically closer to the subject. If you could just take a few more steps toward the tank and have the camera focus, you’d be in business.
Well, the end result we really want is more magnification. “Closer” can desribe two different ways of chieving this, or at least trying to do so. When dealing with macro photography, it’s much more preferable to get physically closer to the subject in order to get the magnification you want. Every lens has a minimum focus distance- how close you can be and still have the lens focus on the subject. It has to do with the focal length of the lens and how it’s built. And there are a few ways to get “closer” in this sense.
However, sometimes when people say “closer” they mean in terms of focal length- “more zoom.” Getting more magnification this way is a bit trickier, because- as previously mentioned- minimum focus distance has much to do with focal length. If you put a larger lens on your SLR camera, you may not achieve the same magnification as with a shorter lens that allows you to focus from a closer distance. If you add a telephoto adapter to your digicam, you will, in the process, alter the dynamic of the camera and its minimum focusing distance. And quite possibly, end up with less magnification.
So, if you want to improve your magnification, you should first concentrate on moving physically closer to your subject by decreasing the minimum focusing distance. Diopters
A good, realtively inexpensive way to reduce your camera’s minimum focus distance, but not without its drawbacks. Diopters look like filters, and attach to the end of your lens. They allow you to focus closer than with the lens alone, thereby achieving greater magnification. However, cheap diopters will negatively impact image quality. You’ll also find that, along with closer minimum focusing distance, you now have a maximum focusing distance while using the diopter. In other words, if you’re too far away from your subject, the lens won’t focus at all. If you want to photograph something a couple feet away, you’ll probably need to remove the diopter.
Make sure you buy a good-quality diopter. There are plenty of cheap ones out there. They’ll help you focus closer, but your image quality may very well take a noticeable hit. You may lose sharpness, see an increase in graininess, color rendition may be dull and unappealing, or you may experience problems with chromatic aberration. However, Canon and Nikon both make excellent quality double-element fiopters that have minimal effects on image quality. I use the Canon 500D model, and have noticed absolutely no drop in image quality. I also bought a cheap set of diopters early on with my digicam, and gave them away to a friend without hesitating when he expressed interest. I don’t miss them one bit, but I’ll never part with my 500D. Extension tubes
This one’s for the SLR users only. Here we have another benefit of interchangeable lenses, and an excellent one indeed- the ability to use extension tubes. These are simple pieces of plastic that go between the lens and the body of the camera. By increasing the distance between the lens and the sensor, the minimum focusing distance is reduced.
What’s the catch? Glad you asked. In order to reap the benefits of extension tubes, you have to sacrifice the most valuable commodity of all. Light. Extension tubes will rob you of anywhere from 1/2 to several stops of light, depending on how much extension you use. So at any given aperture, what would have been 1/60 may now be a shutter speed of 1/15. When photographing aquaria, be prepared to use a tripod with any but the smallest extension tubes. If you want to more magnification than your lens offers for fish shots, consider going with a good double-element diopter rather than tubes.
Still not close enough? Now It’s probably your focal length.
Let’s say you want to photograph something at the back of a 24” deep tank. Let’s also say your digicam has a minimum focus distance of 8”. Probably not the best macro on that camera, but in this case it’s not your problem. The subject is well more than 8” from the lens, yet you’re not getting the magnification you want. Now you’re talking about the need for longer focal length.
Not close enough? Move your subject.
In many fields of photography, it’s a faux pas to manipulate the natural environment in order to frame your photograph. For example, plucking a rose bud off its plant to wedge it between two other flowers. Well, guess what? You’ve already manipulated the environment. You created the display to be something visually pleasing. Nature made the rocks and the corals and the fish, but you chose what would go where. So personally, I see no problem with rearranging the corals to create a different visually pleasing display than the one you’ve already manufactured. It gives you a nice added level of artistic freedom. Consider it an underwater still-life. And, in the case of macros, consider it an opportunity to move that coral from the back of the tank to the front so you can get that ultra-juicy close-up you want.
White Balance
Using Flash
Cropping: How to do it right, and why you shouldn’t plan on it at all.
Sometimes it’s all too tempting to take that nice shot of a fish, blow it up a bit and crop out the background at the same time. Depending on what you plan to do with the photo, it can be a very good thing. However, if you’re aiming for excellence, there are some potential problems that get much, much bigger when you start cropping.
-Noise. If there’s graininess in the photo, the size of the grains will get bigger along with everything else.
-Sharpness. Your photo has to be extremely well-focused to endure a heavy crop.
-Weird sizes. Crop it any way that looks good and share it online all you want. But if you ever want to frame it, you’re going to run into trouble if it’s not a standard size.
-Technique.
