did you use a flash? if so, this is what you're going to get.
If you are photographing something behind glass, turn off the flash and press your lens against the glass. Exposures may be really long if the room is dark, and you're going to need all the stability you can get.
If you insist on using the flash, be sure to shoot at an angle, because if you point your camera directly at the glass, you're going to get something similar to what is shown above. I set my camera to "Auto", ISO 100, flash enabled, and snapped a shot. The smudgy stuff is residue from the noses and hands of children. It's totally disgusting, and I'd rather not have it in my photos.
And if you're shooting an aquarium with really thick glass or acrylic, chances are that you're going to get a reflection even if you do shoot at an angle. If you're shooting with a digital SLR, crank up the ISO for an acceptable shutter speed (consumer cameras are too noise at high ISOs to be effective). Here are some examples of properly exposed aquarium shots, taken a few days ago.
no flash, high iso. notice absence of lit-up snot.
In some cases, you can get fancy and use an off-camera flash. Buy a lens hood that won't let any incidental light in, and push it against the glass, sealing off any possibility of light from the flash hitting the lens. Hold the flash against the glass at various locations and experiment, because sometimes thick glass can reflect from the rear even when you use a lens hood.
I pretty much turn off the flash whenever shooting through glass.
More tips on not using the flash:
- If you're photographing the moon, turn off the flash and expose manually.
- If you're photographing a night city-scape and don't need to light up anything in the foreground, turn off the flash.
- If you're photographing something out of an airplane window, turn off the flash.
- If you're photographing something really far away, turn the flash off and stabilize the camera
- Unless you're only using the flash as fill, it's probably going to nuke the mood of the image. I prefer noisy photos that invoke a mood over lame, flash-nuked images.
Or, you could just ignore my advice. I'll be the one in the back, smirking. ;)