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sbreefer
11/23/2010, 01:25 PM
I cannot seem to get good colorful contrasty photos through my acrylic aquarium. I have considered building a Starfire tank? is the difference significant?

uncleof6
11/23/2010, 10:16 PM
Not really any significant difference. But that is not the problem anyway.

It is a problem of differences in how you see the light and color--with brain interpretation (compensation) and the way the camera interprets the light and color. (either the film or digital media.) It is a very complex subject, encompassing the same principles as a recent "treatise" i did here on RC concerning light and photosynthesis.. I.E. the kelvin scale, correlated (apparent) color temperature, and the way we see it in relation to the actual wavelengths a light source is emitting that the camera will see differently. In photography this translates to white balance and color correction.

Washed out (lack of contrast and richness of color) is an exposure time problem called over exposure. But it is not that simple with a complex scene that has strong highlights and strong shadows, and lighting with an interrupted spectrum, like in an aquarium. Your eyes compensate (brain), however the camera will not.

If you expose for the shadow, your highlights will wash out (over exposed.) Your mid tones (gray) will be over exposed, but your shadows will show the detail that your eyes see. If you expose for the highlights, the highlights will show good detail, but the mid tones will be under exposed, your shadows will go black and lack any detail at all. You may not be aware of these different tones in the scene, because the eyes have a very wide dynamic range. (the brain interpreting the scene) The camera has a rather limited dynamic range. Expose for the mid tones, and you get a more balanced exposure, sacrificing some highlights and and some shadow detail. In this area, the 18% gray card comes in handy for averaging the scene, and some darkroom (for film) or photoshop (for digital) work (dodging and burning) can improve color saturation and contrast. But it is a matter of garbage in, garbage out also. If the camera does not record the detail, you can't bring it out.

Bracketing (series of shots of the same scene taken at equal spaced exposures above and below "correct exposure) is used for complex scenes where averaging the scene just will not get it done. And the best of the lot goes into the darkroom (or photoshop.) HDR (high dynamic range photography) has solved most of the issues with these complex scenes. This is done using a computer to blend 3 or more bracketed shots into a single image, with a resulting dynamic range that the camera cannot capture in a single exposure. No it is not morphing either: if the detail is not there, you can't see it. The results are stunning, but work only for a scene with no motion. e.g. it won't work for an aqaurium--well it will work, but it won't look right.

So basically you have three things here: Your light source is not full spectrum light which will change the color (white) balance. You have a complex (wide dynamic range) scene that the camera cannot reproduce in a single image, and then there is you, and how you "see" the reflected light. (and that varies from individual to individual.

In days past and the 35mm camera, it was all on the photographer, not the camera. A cheap camera could capture images equal to or even better than the expensive camera, depending on who was pushing the button. I don't think that is so true with digital cameras, auto exposure control, auto white balance etc. A good digital can produce good shots, with little effort on the part of the photographer, but a junk camera probably won't (cell phone cameras for instance.) But still a complex scene is going to be a problem. (limited dynamic range) This is where experience and technical knowledge come into play-- and a good digital. (or resort to 35mm film which mimics the human eye response better than digital.)

Photography is an art form, but it is a science also. IF your camera has manual exposure control try under exposing a 1/3 stop, maybe a 1/2 stop and see what happens. A good photo strobe (flash) would help with color, but you will get a bit of reflected light back to the camera, from the acrylic/glass, if the flash is mounted on the camera.

Clay
11/24/2010, 08:31 AM
I think the most relevant part (although Uof6 always seems to be relevant) concerning photography was in the last paragraph. You can change a great deal about the focus and depth of your photos by adjusting the location of the flash or light source. I learned a long time ago that the flash you purchase is just as important as the glass and body. When I got a remote flash, my photography "skill" went up incredibly.