Comparing Whibal6 and PrecisionCap

Since I have the much maligned 70-300 DO, the stickies on this site advise me to shoot raw only. Since the 70-300 DO seems to always render cooler colors than a L, the use of a WB reference becomes critical.

For a recent trip to Kauai, I got myself a Whibal6 card. Not too expensive at 29$ + shipping/tax, given all the fancy calibration that seems to have gone into verifying spectral neutraility and all that. I added a random spring loaded retractor and clipped the Whibal6 to my pant pocket and pulled it out for a quick shot when needed. The only problem with this is that it is big enough that it is not always comfortable to put into your pockets when hiking (digs into your skin etc), plus it is easy to leave behind. I found myself without it on 2 of my 4 long trips in Kauai. Since then I have learnt about precision cap and have decided to try it out. Something stuck to my lens cap is so much more guaranteed to be close to my camera than a thick piece of plastic that is easy to misplace.

So I ordered those. Got them for ~ 15$ each (2X77mm and 1*58mm). They sent me 3*77mm and 2*58mm. Good!

Stuck the precisionCap on (simply following instructions. Painless) and took photos. The same photo with three additional virtual copies (bless LR) and click to WB processed differently. Shots taken on carpet at home, incandescent lighting, with 17-55: ISO: 800, 1/50 sec, f/2.8, @37mm.

Auto WB

HTTP response: 404 | MIME changed to 'image/png' | Byte size: ZERO

WB on PrecisionCap grey area

HTTP response: 404 | MIME changed to 'image/png' | Byte size: ZERO

WB on Whibal6 Grey area

HTTP response: 404 | MIME changed to 'image/png' | Byte size: ZERO

WB on Whibal6 white-point area

HTTP response: 404 | MIME changed to 'image/png' | Byte size: ZERO

• R: 58 - 63
  
• G: 48 - 56
  
• B: 28 - 32

• R: 59.8 - 61.8.
  
• G: 52 - 54.4
  
• B: 31 - 33.8

Very interesting comparison, thanks for posting.

I'm glad you like it. For me: Gray Card…White Paper. What’s best?

chauncey wrote in post #4874119
Very interesting comparison, thanks for posting.

You are welcome. I was searching for a portable, hard wearing and most importantly *something I will not forget to carry* alternative to the whibal6. Found no comparisons so decided to make one to help others stuck in my previous situation.

PhotosGuy wrote in post #4876274
I'm glad you like it. For me: Gray Card…White Paper. What’s best?

PhotosGuy, I have read most if not all of your very informative posts regarding exposure. I never shoot in a studio situation. Mostly travel photography or family candids. So reading exposure in target lighting at the target is something I just cannot do and carrying more stuff is something I'd like to avoid. Carrying a heavy camera and a heavy backpack when hiking has made me appreciate solutions that don't require my carrying new stuff. Maybe I can calibrate the precisionCap grey WRT a white paper when it comes to how my 20D sets exposure and memorize the compensation required to push the grey to the right. The WB greys are much lighter than the 18% grey cards, so hopefully the exposure compensation required to bring it to the exposure level of white-at-right will be less than 2 stops (max on the 20D)

I have tried to WB off of scenes in the photo. But I don't always have white and my eyeballing the correct WB while adjusting the sliders in LR is usually more artistic than accurate and I want an accurate (if incorrect) WB as the starting point. Hence the need for a good/accurate/neutral WB aid. Paper is just not rugged enough for me to take along on a long hike nor is it spectrally neutral. Truth be told I have never considered exposing for white (assuming the tonality of the scene is 5 steps and my scene has white and 5 steps down from white at the scene light levels will not obliterate my shadows). I do try to expose for the highlights now that I have read Bruce Fraser's RAW book and undersand why it is neccesary. After reading your post I was thinking about a portable white source, if needed I will stick some white paper on the inside of my lens cap. Most white paper I have seen is slightly blue, I need to find a white source that is close to white and go from there. Any suggestions ? I will experiment with it and see if th eprecisionCap gray can be used in lieu of white. Will post results on your thread.

-vamsi

TY, This was nice to see. It seems to reveal things we know but don't see demonstrated:

a) Shoot RAW

b) Using a Color Temp gray card for Click-WB processing is far far better than not using one and relying of AWB.

c) The numerical dif in Eyedropper Click-WBing between cards are likely statistically insignificant, especially as there is sensor Color Noise and Luminance Noise at ISO 800. This variation is normal and low, and would be even lower at lower ISOs. Both WB color cards look good.

Jack

No "solution" is perfect. But if the light 500 yards is the same as where you are...

Remember that's only true if you have highlights, and sometimes not even then.
This is not the same process as
Expose to the right

I usually carry the white paper in my pocket for notes, so that's why I use it.

I shoot only RAW, so I expect that I'll be able to adjust before the conversion. Remember, the "correct" WB for any shot may not be the "right" WB? What's "right" for a sunset? Sometimes I want a shot to be warmer than what a purist would term "correct", & might shoot at sunset with a Cloudy pre-set. We used to have to use color correction filters for that.

So in the long run, you should decide what is right for your shots, & have fun doing it!