Lighting Bugs

[BigFuzzy]

The problem, as I see it is that none of the individual lights is strong enough to register unless with really long exposures.
But then you have the problem of the ambient light being exposed during those long exposures as well which often will be brighter than the bugs you're trying to capture or because they move the light source isn't in the frame long enough for it to register on the sensor.

Just not sure how feasible it is unless all the bugs stayed in the same place for a really long time and there was no ambient light during your long exposures.

[ravncat]

They've got to function like a flash, in a way that the length of time that the light is on is not so important - this means that one should probably shoot them with a wide aperture. Seems to me, we need to figure out what the light output of the bug actually is in comparison with the background - and use a short shutter speed to control the ambient exposure (and reduce the ambient as much as we can) and try to use ISO and a Large Aperture to pick up the firefly light (as per a field of them).

If the fireflies are putting out less light than the ambient, it's going to be very difficult - but there should be a dusk time when they are brighter than the background. Since light intensity falls as 1/(r^2) we need to be close to them.

I wish I had a nearby place with lots of fireflies to go check out - but that season is mostly over here. I posit that using a wide aperture and a wide angle lens at a close distance to the bugs with a shorter shutter speed - (can bracket with ISO and shutter speed to find a good background ambient) one might be able to get a better firefly capture. Perhaps something like a 24 1.4 would be ideal. (or a 35 f2 maybe)

Another option that might be interesting is to try and underexpose the blue and red channels - assuming that they are putting out mostly green light - and the sky and ground should be darkish and blue (with the ground grass maybe reflecting more of that blue light than green) we can use (A green or maybe yellow) filter to let through the firefly light and darken the background further - Then try and "right" the white balance in post? - or convert to black and white - maybe using a second normal exposure to bring the sky color back, and use selective coloring with the firefly lights themselves?

That's how I would try to tackle it anyway - I'm not sure how well that would work - till I went out and tried it...

[BigFuzzy]

Ah, I thought they were more like a constant (ambient) light.

Either way, i think the output just isn't strong enough to make it easy to photograph.

But yeah, nice answer Ravncat!

[ravncat]

Originally Posted by BryanC

. Weird flare in the upper corners, too. I

That's called amp-glow, and it's coming from the heat on your sensor from a long exposure. Many cameras have unique signatures (I can tell you when its a d70 or d200)

Long shutterspeeds - the camera being warmer, and higher ISO will make the amp-glow more visible. Not too much you can do about it, unless you are pretty good with image processing and make a second identical exposure with the lenscap on and the eyepiece covered - and use that data to subtract from the first.

You may be able to get a reduction in amp-glow if you use the long exposure noise reduction - but it depends on which camera (As some implement the dark frame subtraction differently)

[SwissJon]

Originally Posted by ravncat

That's called amp-glow, and it's coming from the heat on your sensor from a long exposure. Many cameras have unique signatures (I can tell you when its a d70 or d200)

Nikon seems to have done something about this in the latest models.. I regularly have my shutter open for 30s without it, and up to 10 mins on a few occasions, never seen these glows before.

[mshockley]

Ravncat you have given me some ideas! I'm going to work on this again tonight and see what happens, but your very informative response makes much sense, and totally the opposite of what I was trying to do. My hope was to try and take into account somehow the fact that the little guys "flicker" on and off, and somehow just absolutely flood the resulting image with tiny flicks of light by using a long exposure.

Bryan--at least you have an image to show that contains the firefly lights...lol...that's a heck of a lot more than I got!

SwissJon--I did the same Google search before coming here to my friendly experts, and yeah, it seems this could be trickier than I originally thought!

[mshockley]

Originally Posted by BigFuzzy

Ah, I thought they were more like a constant (ambient) light.

Either way, i think the output just isn't strong enough to make it easy to photograph.

But yeah, nice answer Ravncat!

I'm afraid of this Fuzzy, but if you could see how these look at night out over the field! It's one of those things that really is quite fascinating and I wish I could figure this out......

[ravncat]

Originally Posted by SwissJon

Nikon seems to have done something about this in the latest models.. I regularly have my shutter open for 30s without it, and up to 10 mins on a few occasions, never seen these glows before.

Yeah - the newer models are much better about it - especially as you move up from their lower end cameras. You can still cause it to happen - I can do it on my d700 if I set the ISO crazy high and do a really long exposure