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I am trying work out the setup for photographing large (2 x 6 foot) panels of woodflooring samples. I have experience photographing 3d work, as an sculptor, but am being challenged by glare/even-lighting issues with these very-flat, glossed, panels. (CLARIFICATION: Reflection of the light sources themselves, not reflection of the camera or room is what I'm concerned about).

I had thought that the best option would be soft light but am reading that that only increases the incidence of glare. I have read that I may be best with hard lighting, setup at 45 degrees, one light on each side. This appears to be very effective for the examples I've seen of small paintings and such, but am concerned about the largeness of these panels.

I am trying to get a permanent, reasonably low-cost setup for doing this for a client of mine who needs to take sample photos regularly for a website. What would be the recommended way of ensuring that the entire panel is evenly lit with no glare -- should I mount it horizontally or vertically, will a single hard light on each side be enough or shoudl I have two on each long-side, or one on all four sides? Is constant lighting or a strobe going to be more cost/visually effective?

  • I remember something about using polarizers on the light sources. I have no idea if it be a solution to your problem. – JenSCDC Nov 3 '14 at 20:07
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    You can try to fix the problem of non uniform lighting by taking a few pictures that have different parts illuminated correctly. You can then add up the images in a linear colorspace (linear RGB or XYZ) and then convert to the usual colorspace e.g. SRGB. The pictures must then be taken using a tripod, minor alignment of the pictures may still be necessary. – Count Iblis Nov 3 '14 at 20:43
  • I think a polorizer won't work. But if you have ome handy, or polarizing sunglasses, it's easy to check. – JDługosz Nov 4 '14 at 0:58
  • It's not just using one polarizer, it's using several on different light sources aligned at 90%. At least that's what I seem to remember. – JenSCDC Nov 4 '14 at 1:59
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With strobes, you will have a harder time figuring out how to get it right. With continuous lighting you just move things and see. With still-life you don't have to worry about exposure time (within reason), so that makes it quite practical.

You might also consider sunlight. Outdoors in open shade is great and big. Include a gray target in part of the frame that will be cropped and you can make up for lack of reproducable color temperature.

  • That's my thought on continuous lighting but I don't like to make a choice out of inexperience. Many professional photographers use strobes because they can out-lumen ambient light so there are not two light sources competing. Sunlight is a good choice, of course, but I need year-round reproducability of results and this is Vermont so you're not going to be photographing in December outdoors. – birchbark Nov 4 '14 at 23:58
  • Hence the gray card to make individual lighting differences even or very close to being even. Even in Vermont. ;-) – Robert Koritnik Nov 5 '14 at 17:26
  • Gray card is great for me, but not for my client :(... I need him to walk in, have the camera already pre-set to the right settings, and just click... Otherwise he might shoot on cloudy when it's not-exactly-cloudy and then complains that his shots all seem to lack warmth... Or, he might do a custom white balance with the grey card only to have the light change a few minutes later and not notice. And I'm not about to have them shoot in raw and then spot white balance off the card. Best to have a controlled light situation and shoot in jpeg with settings pre-determined. – birchbark Nov 5 '14 at 22:38
  • Not to mention, no one wants to shoot outside when there's 2 feet of snow and it's negative 15... even if it's sunny. – birchbark Nov 5 '14 at 22:38
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The main reason why there will be reflection on such a surface will be due to light spillage and light bouncing off bright walls. my suggestion is to block this light spillage with Matt Black Cards

Set up your panels; standing or flat, makes no difference, it is how you wish to display them so that you are able to show the maximum beauty of each panel.

Get the panels lit up evenly (choose Lighting that you are most comfortable with) not worrying about the glare at this stage. Alternatively, you can use whatever lighting you want( making sure you white balanced correctly) if you are showing off just a proportion of the panel with light fall off at the other end creating a blurry fall off effect.

Once you have your desired lighting, position black cards around the wood panels (out of Frame) to kill the reflection. you will find that the black cards will not only take the reflection away, but may also cause shadows in other areas, so you will need to balance these with white cards to fill the shadows with light. At this stage, you may find yourself bumping up the light to compensate for the black cards.

It may take you a couple of hours to figure a setup and you will achieve a perfectly balanced result at a relatively low cost.

Take a snap of the final setup on your phone for future reference and proceed to build a more permanent setup based on your snap.

  • Unfortunately I need a consistent sample, nothing artistic in terms of fade-out or fall-off. That was the question. This is like copy work, not an installation shot. – birchbark Nov 5 '14 at 0:00
  • As for the black cards, that's a good point, in this case, we're photographing in a large warehouse, so there's not going to be a lot of reflected light off of side walls. It's not the main problem I'm trying to resolve so much as adeuqate light sources and positioning, especially re: strobe vs continuous. – birchbark Nov 5 '14 at 0:01
  • Sounds like you don't have to worry about competing with variable ambient light, so that's not a compelling reason to avoid continuous lighting. – JDługosz Nov 5 '14 at 2:15
  • I have in the past used Fluorescent tubes as continuous key lights for similar situations. if you have a couple spare that are 6ft in length with starters assembled, It may be worth using one on each long side to light evenly right across the length of the panels. You can then position the black cards to reduce the reflected light/glare and create the contrast that will create depth to the photo and make it pop showing off the colour and texture of the wood. – Abdul Quraishi Nov 5 '14 at 12:00
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You need a tent. I have a small table-top unit and shot perfect photos of a watch with no glare from the glass, and more recently some glass bottles that had horrible reflections (even could see myself!)

Look up lighting tent so you know what I'm talking about. For your setup, get some suitable fabric and string a couple lines of paracord over the sample stage. Drape cloth over lines, letting it reach the floor in back, making an awning in front.

Arrange lamps to make the fabric glow evenly. Modify with small swatches or paper towels to darken areas, any available reflectors to fill in what isn't working.

In my last project I still used photoshop on the tallest bottle as my awning overhang wasn't big enough. Youndo need a hole for the camera and can't complety cover the front-bummer if that's the spot showing dark.

It helps if the lamps are somewhat diffused already, so they'll have umbrellas or diffusers too. I wonder of a sring of LED lights would be good for that, as it can evenly surround the tent.

  • I'm used to using softboxes and the like, but my understanding is that diffuse light is going to have more possible angles of glare. I'm not concerned with REFLECTION so much as GLARE, also. I considered a tent but everything I've read on copy work, photographing flat, varnished artwork, etc, which is pretty much what we're trying to do, highly recommends against soft light. – birchbark Nov 5 '14 at 0:03
  • I think it depends strongly on the exact nature of the finish. I see your point for true flat and small (like paper size) pieces in that the reflection angle can be avoided. But fot a long object and for matte finish or not smooth on the fine scale, itbwill alwaya glare. Thinh of the bright spot on a car window with dirt film left by imperfect wipers: there will be an angle on each micro-feature that reflect right at you, for any angle. Matte finish works the same way, as to non-polished natural surfaces. – JDługosz Nov 5 '14 at 2:24
  • So in your initial experimental shots, get samples of all types of finish. Although not an installation, you can note the exact positions and details to quickly set it up the same way for each session. Take wide-angle snapshots of the setup itself for documentation, too. – JDługosz Nov 5 '14 at 2:27
  • As I recall (it was 20 years ago) the reflection densitometers I worked on followedd a spec that they should light from a bulb straight down to the surface, and measure light from a ring at 45 degree angle reflaction from that point. That is, not diffuse light; but only looking at a small spot. – JDługosz Nov 5 '14 at 2:34
  • Tungsten reflectors, 4 of em, at 45 degrees off the plane, worked great. Way better than I thought they would. I think I will use 6 though as I can notice a slightly darker area in the center though no one else can. I marked your other answer as, though no one really gave what I feel was a complete answer the emphasis on continuous lighting was more on topic and more helpful than anything else I received. – birchbark Nov 5 '14 at 22:41

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