white balance lens caps

Has anyone used a white balance lens cap? I saw one demonstrated the other day and although the idea sounds good, I was wondering if anyone has used one and if they would recommend them. If you have not seen them, they are like an 18% grey card built into a lens cap. You aim at your subject or light source, record the image, then use it to set a custom white balance.

The only big downside I can see is that you'd have to get one for each lens you had. Unless you wanted to just get one, WB with that lens, then swap to the lens you want (and even then, this is far from ideal for various reasons).

I use the lally cap. It is made of a nylon material and has elastic around the edges so you can fit it on various size lenses. Mine goes up to 77 mm and I have used it on my 50mm f/1.8 which is 52mm I believe. I think that it works pretty good so far. It also makes a handy quick release lens cap, you just pull it off and on real fast and start shooting.

Brian Puccio wrote in post #6710539
The only big downside I can see is that you'd have to get one for each lens you had. Unless you wanted to just get one, WB with that lens, then swap to the lens you want (and even then, this is far from ideal for various reasons).

Well, no, you can get one sized for your largest diameter lens and either use a step-up ring to mount it to your smaller lenses or just hold it over them while taking the picture. Of course, unless you just hold it in position, you still have to attach and detach it to your lens.

But I think the bigger downside is in dealing with mixed lighting conditions. They assume you're aiming the camera at the light source; if you've got mixed light sources, are you really going to be able to get a true sample of all of them with the camera pointed at one position? A grey card target at the subject position will give a much more reasonable value in those conditions, whether you use it to set a custom white balance in-camera or for post-processing adjustments of your RAW files.

I use both an Expodisc and a WhiBal card. If the light is fairly consistent and I can point my camera in the general direction of the light source I use the Expodisc to set a Custom White Balance. Otherwise, especially in mixed lighting conditions, I use a WhiBal card.

Either method is fairly easy to use. With the WhiBal you can save a reference shot to adjust your photos later during post processing or you can use the shot to set a Custom White Balance.

James P wrote in post #6709677
Has anyone used a white balance lens cap? I saw one demonstrated the other day and although the idea sounds good, I was wondering if anyone has used one and if they would recommend them. If you have not seen them, they are like an 18% grey card built into a lens cap. You aim at your subject or light source, record the image, then use it to set a custom white balance.

From what i heard it doesn't matter with WB if you are shooting in RAW? Can some one confirm this?

Thanks guys for sharing your experience. I guess I'll stick to my gray card for now.

The notion that it is not nessessary to use a custom white balance because you can adjust WB in PP is, IMHO, just plain wrong. You can adjust so it looks good, (if your monitor is calibrated) but is it what you saw or what you remember?

I have been using one of those Robin Meyers Digital Gray cards, and I must say, I don't think I'll ever need a white balance tool like the ExpoDisc (although I think the X-Rite ColorChecker might be worth it). You just have to make sure the light is hitting it at a 45-degree angle. Or like the WhiBal card, just put in the scene for reference in post-processing.

Coffee Filter...

MinhThien wrote in post #6713510
From what i heard it doesn't matter with WB if you are shooting in RAW? Can some one confirm this?

You can adjust later, but you still need a neutral spot to use as a reference. And a grey card works better for that than an ExpoDisc.