Whitebalance with grey card seems red?

[BlindMan]

Hello folks,

I recently set my white balance using a new grey card. After that all my pictures seem to have a red tint to them.
I'm using a Canon 600D with Elinchrom flash units and a Mennon grey card.
Before using the grey card i just used a piece of paper for setting white ballance. Seems like i get pretty much identical results with paper and the grey card. - When using the paper I manually added blue in the camera settings to compensate for the red tint. - looks like I have to do the same when using the grey card (somehow makes sense )
When I open the files with the grey card in it and hold my eyedropper on it in photoshop, the color in the card is perfect grey (identical RGB values) - but everything looks reddish???
Just calibrated my screen with no improvement.
Same result on 3 different cameras and different monitors.
Any ideas? Does the background have a red tint or is the balance off?

 

[neuroanatomist]

I'm not familiar with the brand you mentioned, but in general gray cards are intended as exposure calibration tools, and not as color calibration tools. In other words, they are specified to be a particular % gray, (e.g. 18%) but they are not necessarily a neutral gray. In fact, some of them have a noticeable color cast.

Instead, you should use a white balance tool that is truly neutral (e.g., the WhiBal card), or better yet a color patch tool such as the X-Rite ColorChecker Passport.

 

[BlindMan]

Wow I thought a grey card were all i needed... ill defenetly check out the colorchecker.
Still not shure why the pictures get a colorcast when using white paper (and a grey card) but looks like i need that passport. Thank you alot!

 

[neuroanatomist]

Still not shure why the pictures get a colorcast when using white paper (and a grey card)

Because white paper isn't really white! White papers have brightening agents added to them, and those are fluorescent chemicals that absorb light in the long UV wagelengths and emit blue light which is added to the light reflected from the paper. So, white paper is actually a little blue (and the 'bright white' papers are even bluer).

When you WB on something with a blue tint, you get a yellow-red tint in your image.

 

[Don Haines]

Still not shure why the pictures get a colorcast when using white paper (and a grey card)

Because white paper isn't really white! White papers have brightening agents added to them, and those are fluorescent chemicals that absorb light in the long UV wagelengths and emit blue light which is added to the light reflected from the paper. So, white paper is actually a little blue (and the 'bright white' papers are even bluer).

When you WB on something with a blue tint, you get a yellow-red tint in your image.

I did not know that! Thanks Neuro, always learning new stuff here....

BTW... my "grey card" is a 30 or 40 year old kodak card.... colour bar on the top half, neutral grey on the bottom half.... It is getting quite worn. Do you have any recomendations for a replacement?

Thanks!

 

[neuroanatomist]

BTW... my "grey card" is a 30 or 40 year old kodak card.... colour bar on the top half, neutral grey on the bottom half.... It is getting quite worn. Do you have any recomendations for a replacement?

I'd look at the WhiBal products from Michael Tapes.

http://michaeltapesdesign.com/whibal.html

True neutral gray, and available in a variety of formats…including one for your keychain.

Alternatively, the ColorChecker Passport also has a neutral gray 'page'.

 

[BlindMan]

Still not shure why the pictures get a colorcast when using white paper (and a grey card)

Because white paper isn't really white! White papers have brightening agents added to them, and those are fluorescent chemicals that absorb light in the long UV wagelengths and emit blue light which is added to the light reflected from the paper. So, white paper is actually a little blue (and the 'bright white' papers are even bluer).

When you WB on something with a blue tint, you get a yellow-red tint in your image.

I figured I couldn't count 100% on paper but didn't think it would be that much off - the grey card must be pretty close to the paper then, since they have about the same amount of colorcast in the pictures. I was sure all grey cards were meant to be neutral greyscale. I guess the one I got may be intended for portraits or similar to add a bit of warmth to the picture. I've never seen anything about tint written on any graycards - they should.
Thanks for the detailed explanation.

Would I need the ColorChecker or will a simple Whibal card do the trick and ensure neutral color in the pictures?
I want the colors to be as close to 100% as they can straight from the camera. - I'll be shooting .jpeg for speed.

 

[neuroanatomist]

Would I need the ColorChecker or will a simple Whibal card do the trick and ensure neutral color in the pictures?
I want the colors to be as close to 100% as they can straight from the camera. - I'll be shooting .jpeg for speed.

If you're shooting in-camera jpg using a custom WB setting, the ColorChecker won't help - the color patches are used to create a profile that you apply in post-processing the RAW images. So…the WhiBal would be a better choice.

 

[mackguyver]

+1 on Neuro's posts and recommendations - I love the Passport. Also, I have several gray cards from back in the day and they all have a horrible red cast to them. I'll throw in another suggestion, too - one that I like because it works as a gray card, focus target, white card, and the white side works as a small reflector - the Lastolite EzyBalance:
http://www.lastolite.com/ezybalance-grey-white-card-20-lllr2050

Would I need the ColorChecker or will a simple Whibal card do the trick and ensure neutral color in the pictures?
I want the colors to be as close to 100% as they can straight from the camera. - I'll be shooting .jpeg for speed.

If you're shooting in-camera jpg using a custom WB setting, the ColorChecker won't help - the color patches are used to create a profile that you apply in post-processing the RAW images. So…the WhiBal would be a better choice.

Neuro, it's a more expensive choice, for sure, but it can be used to set the custom white balance - see Canon's recent post (click on show all pages):
http://learn.usa.canon.com/resources/blogs/2014/20140128_stoner_customwhitebalance_blog.shtml

 

[neuroanatomist]

If you're shooting in-camera jpg using a custom WB setting, the ColorChecker won't help - the color patches are used to create a profile that you apply in post-processing the RAW images. So…the WhiBal would be a better choice.

Neuro, it's a more expensive choice, for sure, but it can be used to set the custom white balance - see Canon's recent post (click on show all pages):
http://learn.usa.canon.com/resources/blogs/2014/20140128_stoner_customwhitebalance_blog.shtml

Sure - I mentioned above that the ColorChecker has a neutral gray "page", and it looks like that's all that's being used in the Canon DLC post. You can buy a prepacked toolbox full of tools, but if all you need is a Phillips screwdriver…

 

[mackguyver]

If you're shooting in-camera jpg using a custom WB setting, the ColorChecker won't help - the color patches are used to create a profile that you apply in post-processing the RAW images. So…the WhiBal would be a better choice.

Neuro, it's a more expensive choice, for sure, but it can be used to set the custom white balance - see Canon's recent post (click on show all pages):
http://learn.usa.canon.com/resources/blogs/2014/20140128_stoner_customwhitebalance_blog.shtml

Sure - I mentioned above that the ColorChecker has a neutral gray "page", and it looks like that's all that's being used in the Canon DLC post. You can buy a prepacked toolbox full of tools, but if all you need is a Phillips screwdriver…

Well said and that's exactly right. WhiBal is just a tad more affordable and practical if you're just trying to white balance.

 

[BlindMan]

Thank you guys! I learned alot today. I Think i will go for the whibal.
Just took a look at the eazybalance... Can i trust that one to be neutral Grey or White? Thx

 

[pwp]

I also use WhiBal and Passport Color Checker as part of my daily kit. Must be the way to go. After messing around with different products, I've settled on this combo as a perfectly stable, repeatable step in my overall color management.

BTW, that gray card of yours will have a color-shift over that amount of time. Throw it away. Kodak recommended that the small color strips that I used to use be replaced every 2-3 years, and they're right. My older ones delivered a subtly different result to a brand new one. Maybe my Passport Color Checker card should be replaced every few years too because of color-shift. I'll take this thread as a heads-up on this.

Last year with my plastic WhiBal card, I was getting an inexplicable magenta shift. Turns out all this heavily used card needed was a good wash. Hah!

Good luck. Color management is an important area, full of sneaky little traps.

-pw

 

[neuroanatomist]

Last year with my plastic WhiBal card, I was getting an inexplicable magenta shift. Turns out all this heavily used card needed was a good wash. Hah!

If washing doesn't do the trick, take some fine sandpaper to the WhiBal card. Not kidding!

 

[dcm]

I'm not familiar with the brand you mentioned, but in general gray cards are intended as exposure calibration tools, and not as color calibration tools. In other words, they are specified to be a particular % gray, (e.g. 18%) but they are not necessarily a neutral gray. In fact, some of them have a noticeable color cast.

Instead, you should use a white balance tool that is truly neutral (e.g., the WhiBal card), or better yet a color patch tool such as the X-Rite ColorChecker Passport.

How/when do you use the ColorChecker in your workflow?

 

[wickidwombat]

I'm not familiar with the brand you mentioned, but in general gray cards are intended as exposure calibration tools, and not as color calibration tools. In other words, they are specified to be a particular % gray, (e.g. 18%) but they are not necessarily a neutral gray. In fact, some of them have a noticeable color cast.

Instead, you should use a white balance tool that is truly neutral (e.g., the WhiBal card), or better yet a color patch tool such as the X-Rite ColorChecker Passport.

How/when do you use the ColorChecker in your workflow?

search for adorama and colorchecker on youtube they have a really good step by step tutorial through the whole workflow

 

[pwp]

How/when do you use the ColorChecker in your workflow?

Read up:
http://xritephoto.com/ph_product_overview.aspx?id=1257&
http://www.luminous-landscape.com/reviews/accessories/colorchecker-psssport.shtml
http://www.northlight-images.co.uk/reviews/photography/colorchecker-passport_1.html
http://www.slrlounge.com/review-x-rite-color-checker-passport

-pw

 

[agierke]

Blindman,

It seems to me that the bike in your picture is fairly neutral. The black tires, silver wheels, and the bike frame don't seem to be carrying much of a cast at all...which is what I would expect being that they are lit by your strobes.

A potential problem enters the equation in that you have a good amount of light fall off on your background. There are a number of things that can cause a color shift in areas of a photo that aren't being fully illuminated by your strobes. These causes can include:

1. An ambient light source bleeding into the exposure, particularly the shadows
2. A portion of your strobe light bouncing off a colored object (walls, ceiling, furniture) picking up a color cast and projecting that cast on the background. In this scenario, any direct strobe exposure wouldn't exhibit the color cast.
3. Your strobes themselves operate at a certain color temperature that could be off from a neutral temperature...thus shifting the color of the areas not being fully lit by them when you balance for that light.
4. Modifiers can also shift color balance of the strobe leading to problems described in # 3
5. It appears your using a grey seemless, these can exhibit different color characteristics when lit or not lit and it varies among different brands.

You should certainly follow the advice of others concerning white balancing techniques but it is important to understand that there are other factors that contribute to the characteristics of color in a photo even in a studio environment. Knowing how the color temperature of light works is important in controlling your white balance. Light sources, modifiers, environment, and lighting technique can all contribute to color shifting in a photo...even when a white balance technique is used.

I would advise looking into these different aspects as well as refining your white balance technique.

 

[BlindMan]

UPDATE!
I have been reading about the Mennon grey card and according to the manual it should be suitable for correct whitebalance.
http://www.mennon-usa.com/store/media/mennongreycard.pdf
Some places like amazon state its only the white side that is suitable:
http://www.amazon.com/Mennon-Cards-inches-percent-White/dp/B0019BJZAA

So I did a side by side test (attached) and both seems to be off. the grey looks red and the white looks green.
The grey is actually not spot on and has a little less red than supposed according to photoshop reading.

I am pretty sure the is no ambient occlusion/colorcast from objects/walls etc.

 

[photonius]

Hello folks,

I recently set my white balance using a new grey card. After that all my pictures seem to have a red tint to them.
I'm using a Canon 600D with Elinchrom flash units and a Mennon grey card.
Before using the grey card i just used a piece of paper for setting white ballance. Seems like i get pretty much identical results with paper and the grey card. - When using the paper I manually added blue in the camera settings to compensate for the red tint. - looks like I have to do the same when using the grey card (somehow makes sense )
When I open the files with the grey card in it and hold my eyedropper on it in photoshop, the color in the card is perfect grey (identical RGB values) - but everything looks reddish???
Just calibrated my screen with no improvement.
Same result on 3 different cameras and different monitors.
Any ideas? Does the background have a red tint or is the balance off?

measuring this picture over here, it does have more red in the RGB, so the background is not neutral,