how to shoot white as white and not grey?

babygodzilla

So this is probably a classic case of white turning into 80% grey (or something like that) in the world of photography. Here is a hair clilp on a white table as the background. As you can see the white table is not white, it is greyish, and it is fugly. The question is how do I shoot the white background as actual white without overexposing the subject? I shot this using an on-camera SB-900 that I bounced off the ceiling.

Thanks

Toshido

No idea, but I do know what I would try...

My kid has an art desk with a backlit translucent desktop. I would turn that on, put a clean white whatever on it then put the subject on top of that.

No idea if it would work but that is what I would try. Being limited to on camera flash though I have no idea...

Glass table top with a lamp below it. Expose with a flash for the subject and longer exposure to whiten background?

ABCL

Personally I have a custom white balance setting that I dialed into my camera. By adding a touch of blue, white appears as white straight from camera, I've also added a bit of green to offset the blueish tone that would occur.
With this combination (and a flash) at standard exposure settings I get perfect whites with no overexposed parts (ok, maybe a pixel or two).

pathfinder

babygodzilla wrote:

So this is probably a classic case of white turning into 80% grey (or something like that) in the world of photography. Here is a hair clilp on a white table as the background. As you can see the white table is not white, it is greyish, and it is fugly. The question is how do I shoot the white background as actual white without overexposing the subject? I shot this using an on-camera SB-900 that I bounced off the ceiling.

Thanks

There are two issues entangled here - white balance and exposure, both of which can be improved in Adobe Camera RAW IF YOU SHOOT RAW.

If you do not, you must have a custom white balance and a VERY accurate exposure - within 1/3 of a stop in my opinion. You want your white background to read about 245,245,245 in Photoshop = white, neutral but not blown out.

Here is a discussion I did of white balance tools - http://www.dgrin.com/showthread.php?t=90438 - I do not favor one tool over the other, but using one of them will save you tons of work if you are shooting jpgs.

Try shooting a Kodak grey step scale and getting in the camera jpgs to render blacks black, whites white and mid greys middle grey, and you will find out what I am talking about.

If your paper background is really white, metering off it and setting your exposure about 2 stops hotter than mid grey made be all you need in terms of exposure. Set your camera histogram to display all three RGB channels - you want to see a spike near the right, but not all the way to the right - if all three channels are equal, you will have a very bright neutral color - a white. Use this exposure for your image of the ribbon, and you should be fine.

You can even use the proper exposure of the white background to set a custom white balance as well - setting a custom white balance will be described in your camera's manual.

If you shoot RAW, use the eye dropper to set your white balance on an area of the white background to drive it to white in ACR.

babygodzilla

pathfinder wrote:

There are two issues entangled here - white balance and exposure, both of which can be improved in Adobe Camera RAW IF YOU SHOOT RAW.

If you do not, you must have a custom white balance and a VERY accurate exposure - within 1/3 of a stop in my opinion. You want your white background to read about 245,245,245 in Photoshop = white, neutral but not blown out.

Here is a discussion I did of white balance tools - http://www.dgrin.com/showthread.php?t=90438 - I do not favor one tool over the other, but using one of them will save you tons of work if you are shooting jpgs.

Try shooting a Kodak grey step scale and getting in the camera jpgs to render blacks black, whites white and mid greys middle grey, and you will find out what I am talking about.

If your paper background is really white, metering off it and setting your exposure about 2 stops hotter than mid grey made be all you need in terms of exposure. Set your camera histogram to display all three RGB channels - you want to see a spike near the right, but not all the way to the right - if all three channels are equal, you will have a very bright neutral color - a white. Use this exposure for your image of the ribbon, and you should be fine.

You can even use the proper exposure of the white background to set a custom white balance as well - setting a custom white balance will be described in your camera's manual.

If you shoot RAW, use the eye dropper to set your white balance on an area of the white background to drive it to white in ACR.

luckily i did shoot RAW. so what should I do to the white balance? make it cooler? and then increase the exposure?

ziggy53

The problem with the scene shown is that the chrome pieces can be brighter than white in the form of spectral highlights. If you try to maintain definition and detail in the chrome, you "must" expose the white as a gray/grey.

It is often suitable to expose the scene correctly for the subjects, and then use Photoshop to "remove" the background, something like this:



Review Andy's most excellent tutorial about this very subject:

http://www.dgrin.com/showpost.php?p=46354&postcount=1

babygodzilla

wait im sorry. did you make a change in the example above? I think it's whiter but I'm not sure.

babygodzilla

thanks for the tutorial. actually i was hoping to find out how to do this correctly photography-wise, and not in photoshop. any tips for that?

pathfinder

From my post above http://www.dgrin.com/showpost.php?p=1373261&postcount=4 -- If your paper background is really white, metering off it and setting your exposure about 2 stops hotter than mid grey made be all you need in terms of exposure. Set your camera histogram to display all three RGB channels - you want to see a spike near the right, but not all the way to the right - if all three channels are equal, you will have a very bright neutral color - a white. Use this exposure for your image of the ribbon, and you should be fine.

babygodzilla

hey thanks! sorry i think i scrolled over your response and didn't see it. i'll give that a try.

thanks again!

babygodzilla

pathfinder wrote:

From my post above http://www.dgrin.com/showpost.php?p=1373261&postcount=4 -- If your paper background is really white, metering off it and setting your exposure about 2 stops hotter than mid grey made be all you need in terms of exposure. Set your camera histogram to display all three RGB channels - you want to see a spike near the right, but not all the way to the right - if all three channels are equal, you will have a very bright neutral color - a white. Use this exposure for your image of the ribbon, and you should be fine.

so i read over your instructions again, and i haven't tried it with a camera, but I did try it in Lightroom using the RAW image. I increased the exposure and while the background is now whiter, I think the subject is over-exposed, no? or is it an optical illusion? im not sure..

pathfinder

If you truly feel the yellow ribbon is over exposed when the white is exposed correctly ( ~ 2 stops + EC for a pure white bg) then in the RAW converted you could dial back the luminosity slider for yellows.

Or you could open the file as a Smart Object, create a new unlinked copy of the background layer in Photoshop and reopen the newer layer in Adobe Camera Raw to redo the exposure of the yellow ribbon and then mask the two layers to get what you desire....

Many different ways to handle this in PS.

babygodzilla

pathfinder wrote:

If you truly feel the yellow ribbon is over exposed when the white is exposed correctly ( ~ 2 stops + EC for a pure white bg) then in the RAW converted you could dial back the luminosity slider for yellows.

Or you could open the file as a Smart Object, create a new unlinked copy of the background layer in Photoshop and reopen the newer layer in Adobe Camera Raw to redo the exposure of the yellow ribbon and then mask the two layers to get what you desire....

Many different ways to handle this in PS.

ahh of course yes the luminosity. i will try that, thanks! is there an easy way to apply this to a batch of images in LR? maybe make a smart preset?

babygodzilla

babygodzilla wrote:

ahh of course yes the luminosity. i will try that, thanks! is there an easy way to apply this to a batch of images in LR? maybe make a smart preset?

anyone? smart preset? increase exposure for white color only and not other colors?

pathfinder

Exposure slider controls the white point - use the yellow slider to decrease its luminosity.