Painting with light

[Northern Limits]

After reading this thread a while ago http://forums.railpictures.net/showt...painting+light I thought I would give light painting a try.

PhotoID: 334884 Photograph © Jim Dorst

I don't have access to megawatt lights, and this spot was really dark (country side dark). So I gave it a try with my flash unit.
Even after about a 4 minute exposure and 5-6 flashes I had to lighten this quite a bit to get it accepted.
I tried 4 exposures with differing results. My last shot I kept the shutter open for 5 minutes and directed the flash more, so the result is brighter. In the first 3 I used a reflector on the flash unit for softer light.

Any experience you want to share here? Chime in.

How do you deal with the digital noise factor?

[bigbassloyd]

Noise is a minimal issue when you get the exposure right, even at higher ISO settings. That's the only thing you can do to reduce / prevent it. Even on ISO 100, the noise will get out of control after more a couple stops of increased exposure. If you can start properly exposing the night shots, the sky is the limit for clean compositions.

And with proper exposures, I don't have to use the camera's built in long exposure noise reduction (aka stand there twice as long for the black frame subtraction to fire). The few hot pixels which are bound to occur are easily fixed in post - process. (I even use MS paint for that.. HAHA!)

Here's how I get the exposure right without wasting an entire night on it. I fire ISO 1600 test shots at whatever f stop I decide on. When I get the right exposure at 1600 (let's say 60 seconds) then I use dumb math to get my proper exposure @ ISO 100 (1600 - 60s, 800 - 120s, 400 - 240s, 200 - 480s, 100 - 960s) then I fire the money shot.

And buy a cheap 1 million candle power spotlight for 20 bucks. Much easier to work with if you're an aspiring painter.

Good luck at mastering the night!

Loyd L.

[trainboysd40]

I was wondering why you had so much noise =) Time to open up the aperture a bit. I rarely do night photography past F/8.

[Northern Limits]

Thanks for the pointers.
Higher ISO for less noise? That almost sounds ironic. But then I really didn't have an idea where to start. My last night shots were with a film camera shooting fireworks.
Probably won't get an interesting subject like that one again for a while.
BTW, I did sort of get the effect I was looking for on this shot.

[Diamond D]

Originally Posted by Northern Limits

Thanks for the pointers.
Higher ISO for less noise? That almost sounds ironic.

With the high ISO (1600) he's just talking about a test shot to gauge proper exposure without having to do a bunch of 5-10 minute exposures getting "ready". Bump up to 1600 and maybe f/4 and pick a shutter speed (30 secs?) and see what the histogram looks like. You want it as far to the right as possible without clipping the highlights. As others have said, getting the exposure right is the way to avoid noise, the noise comes up when you have to apply a lot of brightening to a file. Once you have a successful test shot, then you dial back to ISO 100 or 200, that's either 4 or 3 stops from 1600, so increase your shutter speed accordingly and you will maintain the same exposure value.

One thing to watch out for, and it can be hard when it's very dark out, is where the ambient light is casting shadows. I have had this same problem as I see here, which is the tripod shadow on the lower right of the image. Careful camera location and framing are one way to take care of it, or flash the ground and knock out the shadow.

If you are in a location where it's safe and OK and do so, the best way to learn what looks good is practice practice practice.