View Full Version : Lighting for photographing metal panels


mike44
10-26-2005, 10:35 PM
Hi,
Forgive me if this is the wrong forum to ask in.
I work in research for making paints.One of my jobs is photographing metal panels, normally 6 x 4 inches, coated in different colour paints.
I have two main problems, one is lighting the panel(s) so I get the best colour reproduction and the other is glare or reflections.
My camera is a Canon powershot S50, so I have a fair selection of settings. I have access to a lightbox which is used for matching the colours in the paints. This has five different sets of lamps to match different light settings, one simulates daylight, another UV, I'm not sure about the rest. Most of these are fluorescent tubes.
What I would like to ask is for suggestions for equipment or lighting setups to overcome these problems?
Thanks,
Mike44

another view
10-28-2005, 05:26 PM
I'd use the daylight setting - it's closest to what the camera is "used" to working with. Check this other thread here (http://forums.photographyreview.com/showthread.php?t=15384) for some other ideas, the project is fairly similar.

mike44
10-28-2005, 11:45 PM
Thanks for your answer. The project is similar.
I have not heard of foamcore, how is it used in this setting? Could I get the same effect with boards painted in a matt paint? Apologies for the extra questions.
One of my main jobs today will be to try and source a supplier for foamcore.

mjs1973
10-29-2005, 02:55 AM
I just read something in the new issue of Outdoor Photographer about taking picks of "glossy" things. The article was dealing with glossy artwork, but the info might help you out too. Basically what they said was to polarize the light to take away the glare. They did this by placing a polarizing material over the flashes, and I think the lens as well. Sorry I don't have more details about it...

another view
10-29-2005, 08:33 AM
Foam core board is usually about 1/4" thick, and basically it's like two pieces of poster board with a rigid foam core. Most craft stores (Michael's, Hobby Lobby, etc) should have it. You would have the same effect by painting plywood sheets white, but these are much lighter in weight so probably easier to work with and tape into position.

Polarizing material is hard to find - B&H has it though. It's expensive and can give some really neat special effects, but I'd save that for after you're getting good "straight" results.

darkman
10-29-2005, 03:49 PM
Hi,
I have two main problems, one is lighting the panel(s) so I get the best colour reproduction and the other is glare or reflections.
Mike44

For the best color reproduction I would use a gray card in a test shot. Use levels or curves in your editor. Grab the gray eye dropper and select the gray. If the s50 has a raw mode, use that and click white balance, still using a gray card, on this test image.

There are a couple of ways to reduce specular highlights (reflections). The main one is to use a very large light lights source. Large is in terms of the size of the panel and distance to the panel. The closer to the panel and the larger the source (like a SB) compared to the panel the less your specular highlights will be.

The next step would be to add a polarizer to the camera. This will help some. The very best would be to cross-polarize. Buy a sheet of polarizing gel to go over the light to polarize it. Then use another a polarizer on your camera.

mike44
10-29-2005, 07:01 PM
Hi, thank you for your answers. I managed to find some foam core board at my local stationery store, they just call it foam board here in the UK.
I'll try experimenting with the other suggestions, it would appear I still have a lot to learn.
Once again, thanks,
Mike44