Luminous Landscape Forum

Equipment & Techniques => Beginner's Questions => Topic started by: RMW on March 31, 2020, 05:48:16 pm

Title: Setting White point in a kayak
Post by: RMW on March 31, 2020, 05:48:16 pm
Hello All.

I go out in a kayak in the swamps and bayous of Louisiana. The boat is just 12' long and carrying any extra gear is impractical if not impossible.

My question is this: If I focus on the aluminum portion of the paddle, can that give an accurate white point for where I am, at least for the time being? I have the camera in Raw mode. When I've tried this I get wildly off measurements- something like 4000 when I know in the midday light it's closer to 5000. Could being under the foliage of trees make that much difference?  Or is it likely to be something else?

Comments and suggestions most welcome.

Thanks for reading.

Richard
Title: Re: Setting White point in a kayak
Post by: MattBurt on March 31, 2020, 07:26:08 pm
Are you doing this in post or in camera?
I often travel light on foot, a bike, or on skis and I just shoot raw with auto white balance and then set it in post with the dropper in LR on a neutral color in the shot and/or manually adjust from there.

I suspect your paddle could reflect all sorts of surrounding colors which is why your results are inconsistent.

You could also paint or tape a piece of your boat or paddle with something that you could use for WB sampling.
Title: Re: Setting White point in a kayak
Post by: RMW on March 31, 2020, 08:11:00 pm
Matt.
Doing this in camera.
Just as you do, I set white balance in post, but sometimes I can't be sure I can find a neutral color in the image.
I think I'll try taping some duct tape on the hull and using that. Thank you for suggesting that.
Richard
Title: Re: Setting White point in a kayak
Post by: BobShaw on March 31, 2020, 08:56:05 pm
The duct tape will only work if it is actually neutral. Probably better than nothing. Take a shot of the tape and a grey card or Passport and compare. You could just carry a passport if it really matters or cut up a grey card and use a new piece every couple of times.
Title: Re: Setting White point in a kayak
Post by: RMW on March 31, 2020, 09:21:55 pm
Hi Bob.
Thanks for your suggestions.
I guess a grey card would work if I taped it to the hull. I could bring a Passport along, but it's gonna seem like clutter - at first, at least.
And I'll try comparing the duct tape and a grey card.
Will report back !
Richard
Title: Re: Setting White point in a kayak
Post by: nirpat89 on April 05, 2020, 07:18:16 am
Hi Bob.
Thanks for your suggestions.
I guess a grey card would work if I taped it to the hull. I could bring a Passport along, but it's gonna seem like clutter - at first, at least.
And I'll try comparing the duct tape and a grey card.
Will report back !
Richard

Teflon tape works as a good substitute for neutral white. 
Title: Re: Setting White point in a kayak
Post by: PeterAit on April 05, 2020, 12:12:07 pm
I think this is unneeded fussing. In my 20 years of digital photography I have never set a camera's white balance to anything but auto, and my photos have been fine. Nothing that could not be corrected in Lightroom. Shoot raw, of course!
Title: Re: Setting White point in a kayak
Post by: MattBurt on April 06, 2020, 02:04:21 pm
I think this is unneeded fussing. In my 20 years of digital photography I have never set a camera's white balance to anything but auto, and my photos have been fine. Nothing that could not be corrected in Lightroom. Shoot raw, of course!

I agree but that wasn't the question. :)
Title: Re: Setting White point in a kayak
Post by: EricV on April 06, 2020, 07:03:53 pm
White balance can be altered non-destructively during post-processing of a raw photo, so the white balance setting in camera is unimportant.  The question is how to determine the correct white balance in post-processing.  If you want to do better than simply adjusting each image to personal taste, a grey card is the answer.  I carry around a small grey card in my pocket, then when the light changes, I waste a shot to capture the grey card (hand held and probably out of focus).  In LR develop module, I adjust white balance for the card, then transfer (sync) that adjustment to nearby photos taken in similar light.