Photographing item with dual tone (e.g. black and pink pistol)

amadaras · Mar 27, 2014

New to the forum, so I am not sure if I am posting this in the correct location. Anyways, be kind.

I am a product photographer for a local company that sells airguns. While most items I can photograph very well, I always struggle with items that have a high contrast in color. We have some guns that are dual tone (black and silver, black and pink, black and green, etc) and I have a hard time finding balance. The blacks are always very black, and the bright colors are always blown out.

I have a very simple setup; two hotlights with umbrellas, and some reflectors. The camera I work with is an old Canon 50D. The tripod is... crap.

While I normally would just use a multiple exposure to expose each area correctly, my tripod is not the most stable and will move between shots (more than just a little bit), making multiple exposures next to impossible.

Any tips or tricks to help me out?
Thanks!

hotdrop · Mar 27, 2014

Remote Triggers will help if you want to do multiple exposures or continuous shooting to turn off lights, unless the tripod drifts or the shutter movement actually shifts the image (you could shoot a target in the corner if you really want and adjust you image such that the target is consistent as well then crop it out). Another thing you can do is mask out the light to the areas you don't want to over expose using a Piece of glass covered with black tape in the rough shape of the highlights then position it such that it is just outside the FOV of the camera in the direct path of one or both of your lights. Do you have any pictures you can share of things that got blown out?

Gavjenks · Mar 27, 2014

While I normally would just use a multiple exposure to expose each area correctly, my tripod is not the most stable and will move between shots (more than just a little bit), making multiple exposures next to impossible.

I think you just answered your own question there.

Scatterbrained · Mar 27, 2014

As I posted in your other, duplicate thread, how about showing us both your set up and a shot you're having issues with. This can be done in one exposure if you know how to place your lights and flags.

Gavjenks · Mar 27, 2014

If the reflectance of the black and non-black parts of the guns are more stops different than the dynamic range of his camera, then it may not be possible (without something like attempting to light different parts separately, which depends on how the two-toning is arranged on the piece as to whether it is feasible). Multiple exposures may be easiest. or potentially necessary in extreme cases. Although feathering light may also work, if the pink color is all on one side or all on the top of the gun or something.

Oh do make sure though that you're shooting at ISO 100. You have the greatest dynamic range at your low ISOs. If you're at 400 or something you might be losing two or more stops of your dynamic range, potentially, and that could be the entire source of the problem right there.

(Also no matter what solution turns out to be easiest, you need to replace a tripod that frickin' moves across the room from a shutter actuation (!) That's just ridiculous)

Scatterbrained · Mar 27, 2014

I disagree. It's all about being able to control your light; using diffusers, reflectors, flags, scrims, gobos, what have you.

It's all about using the appropriate tools to control the light.

Gavjenks · Mar 27, 2014

That's some nice lighting, yes, but which of those pieces of equipment exactly is responsible for reducing the dynamic range between the black and white internal seams/edges in the middle of the shoe? I'm pretty sure none of them. If the two were 20 stops apart in reflectance, you'd still have to take more than one exposure or have blown out highlights or blocked shadows. The shoe just simply didn't have too much dynamic range for your camera.

Scatterbrained · Mar 27, 2014

The shoe is gloss white and black. Doesn't get much farther apart than that. The dot keeps the white from blowing out, the mirror lifts the blacks in the sole. That's the point. The watch is polished stainless steel, brushed stainless, and matte carbon fiber. Pretty high contrast range. Aside from that, exposure is exposure. If you meter the light at f/5.6, whatever you put there will be properly exposed at f/5.6. Highly reflective subjects (i.e. polished materials like the watch) being the exception, where you are shooting the reflection and not the material itself. Even then it's not an issue of adding more light, it's an issue of putting the diffusion material or reflector where they will fill the angles of reflectance relative to the camera. This isn't rocket science you know.

Gavjenks · Mar 27, 2014

We are just talking about different things, I think. You're talking about regions, like a shadowy sole area of the shoe that would be indirectly lit if not for a mirror. I'm talking about sharp edges, that can't possibly be lit differently because the change happens in a 1/10th of a millimeter (there are common materials with much higher and lower reflectances than shoe pleathery stuff, or than carbon fiber and brushed metal. Especially if the pink in the guns is fluorescent, in which case it can "reflect" more than 100%! Which I've seen before)

Anyway, in all likelihood it's probably both things and any of the above solutions alone would be enough to solve it, and the OPs question has been answered many times over.

I just find hypotheticals like this fascinating, no offense (the product photos are fantastic). In this case, the question "Are there common materials that would have such a high reflectance difference that if they formed a single flat edge together, modern cameras simply cant capture them?" I think the answer is "no" for something like a D800 used at its optimal 100ISO, but probably "yes" for a 50D used at say ISO 400 by somebody who might not know better. Whether that's going on here, no idea.

Scatterbrained · Mar 27, 2014

Take a look at the shoe. It's gloss white and jet black. The only reason the dot was needed for the heel was because the heel was closest to the light, therefore it was brighter (inverse square law and all that). At full resolution the shoe has detail in the whites and detail in the blacks, which was my point. If the meter says the light is f/5.6, then at f/5.6 you'll get a correct exposure. It doesn't matter what color the item is. At f/5.6 it will be rendered accurately.

When it comes to reflectance DR has nothing to do with being able to capture the scene. What matters is lighting it in a way that the light source is reflected into the camera. Working in a controlled, studio setting DR simply doesn't matter. A camera phone has all the DR you need in a studio. What matters in a studio camera is resolution (both MP and outright detail resolving ability) and color.

Scatterbrained · Mar 28, 2014

Amadaras, I don't own any air pistols, so I grabbed the only gun I have that remotely fits the description of what you're dealing with. It's semi-polished stainless steel with an anodized black grip. The lighting set up for this is actually quite simple and works far more often than it doesn't for most small products. Granted the set-up I've used is a bit more complex, but even without the extraneous flag, finger, reflector, and mirror the set up will work, it just requires a bit more burning in post. Of course if you're shooting on white then that wouldn't even matter.

Single light from behind the subject through a sheet of vellum (drafting paper) that's been pulled over the set. Black foamcore as a flag to knock down the light hitting the top of the set above the pistol. White reflector under the camera to bring white reflections back into the lower front side of the pistol. Strip of black Cinefoil on the reflector to break up the white reflection on the barrel. Mirror on the lightstand camera left to bring some hard light in across the gun, providing a highlight down the back of the gun and some texture to the grip. Finger scrim under the vellum to knock down the light on set camera left. High camera angle with long focal length to both reduce perspective distortion and minimize the angles of reflectance I have to fill to get a white reflection across the metal.

And just to cover any concerns about pink :mrgreen: :wink:

:

Gavjenks · Mar 28, 2014

Scatterbrained said:
Take a look at the shoe. It's gloss white and jet black. The only reason the dot was needed for the heel was because the heel was closest to the light, therefore it was brighter (inverse square law and all that). At full resolution the shoe has detail in the whites and detail in the blacks, which was my point. If the meter says the light is f/5.6, then at f/5.6 you'll get a correct exposure. It doesn't matter what color the item is. At f/5.6 it will be rendered accurately.

When it comes to reflectance DR has nothing to do with being able to capture the scene. What matters is lighting it in a way that the light source is reflected into the camera. Working in a controlled, studio setting DR simply doesn't matter. A camera phone has all the DR you need in a studio. What matters in a studio camera is resolution (both MP and outright detail resolving ability) and color.

It might not matter ENOUGH to screw you up, depending on your ISO and camera, but of course it matters.

Hypothetically, let's say you have an edge:
Black side = 0.5% reflectance
White side = fluorescent material with 175% reflectance

You can't light them differently, because they are right next to each other. So whatever light you shine will hit both equally. The two surfaces have a difference of 8.5 stops, so if your camera at current settings has only 8 stops of dynamic range, it will either blow out the highlights or the shadows even AT perfect metering. Imperfect metering will simply make one of those even worse.

If you shoot 200 photons of visible (and 200 photons of UV, all flashes) at it, then you'll get back 1 photon and 175 photons respectively, i.e. 8.5 stops
If you shoot 4000 photons of each at it, then you'll get back 20 and 3,500, still 8.5 stops

So no matter what strength your lights, it's still beyond your camera's range, and no matter what setup, the edge is instantaeous and impossible to light separately

Your images don't really accomplish anything with regard to this, because simply being pink doesn't have anything to do with reflectance, your gun you have there is brushed nickel or something which is utterly different reflectance than polished chrome, say, etc. etc. AND you probably have a much better camera than the 50D AND the OP might be using it at a higher ISO

Scatterbrained · Mar 28, 2014

Digital cameras have both IR and UV blocking filters over the sensors these days.

Of course, if that's not enough you could always get a UV filter for your lens, you know, for protection.

Of course, there's also polarizing films and filters that can be used both over the lights and on the lenses to further control the lights/reflections. . . . . . . .

Gavjenks · Mar 28, 2014

Scatterbrained said:
Digital cameras have both IR and UV blocking filters over the sensors these days. Of course, if that's not enough you could always get a UV filter for your lens, you know, for protection. Of course, there's also polarizing films and filters that can be used both over the lights and on the lenses to further control the lights/reflections. . . . . . . .

I said fluorescent material. Fluorescence means material that absorbs UV light and then converts the radiant energy into emitted visible light instead, thus appearing to "reflect" (actually a combination of reflectance + chemical emittance) more visible light than the amount of visible light hitting it.

Thus, by the time it reaches your lens or sensor, it is all visible already, not UV anymore, and UV filters are irrelevant. (You could put a UV absorbing gel on the flash, yes, which would be a solution if that were the case, but probably expensive and difficult to find for a 4 foot softbox)

That's why dayglow hunting vests, or liferafts, for instance, appear so unnaturally bright orange to your eyes: More then 100% of the visible light hitting them is coming off of them as visible light, because a lot of the UV is also being converted on the surface. Your retinas can't see UV either, just like your camera can't see it very well. But that doesn't matetr because it's visible already when it gets there.

Scatterbrained · Mar 28, 2014

You're trying really hard here. You do know that going up a stop doubles the amount of light right? Meters measure to medium gray (18%). Rule of thumb is, two and a half stops up will give you white and four and a half down will render black. You're talking about a difference of less than one full stop. Not an issue. As a matter of fact, I just took my florescent safety vest that I wear when riding my motorcycle at night, and put it under the gun (in place of the tiles), imagine my surprise when the image came out just fine.