There is a way more reliable DIY way than printing:
https://photographylife.com/diy-reliable-and-cheap-universal-white-balance-reference-device
I tried it and compared the result with a real gray card. I was unable
to see a difference between both methods. So, teflon comes close enough
at least for my visual perception :-)
Best regards,
Martin
On 22.02.2017 05:21, Michael wrote:
Well, I guess I can try to print a gray card!
Anyone know what the code is for 18% gray? If 18% is right in the
middle of the shades of gray I found one page
(http://www.computerhope.com/cgi-bin/htmlcolor.pl?c=808080) that says
the code is:
808080
and according to the same page it is made up of equal part RGB
*W3C Color Name:* Grey
*RGB:* 128, 128, 128
*HSL:* 0.00, 0.00, 0.50
so what is the authoritative answer?
On Tue, Feb 21, 2017 at 7:53 PM, Marcus Sundman <sund...@iki.fi
<mailto:sund...@iki.fi>> wrote:
On 21/02/17 23:16, Michael wrote:
is there something where we can take a picture of a gray card
and then we click on it and then dt will adjust all of the
colors so that the gray card is
33-33-33%?
Usually you use "18% gray" meaning a card that reflects 18% of the
light in the visible spectrum and equal amounts of red, green and
blue.
It might actually be nice if the whitebalance module would support
exposure adjustment as well, to make a selected area a specific
brightness, or what do others think?
by the way: what is the color of the remaining 1%
That "33-33-33%" is your invention, so nobody but you can know
what "remaining 1%" you are talking about. If you were talking
about the reflected % of the individual color channels then there
is no "remaining 1%", but the "remaining" (absorbed) amounts of
light are 67%, 67% and 67%, respectively.
- Marcus
--
:-)~MIKE~(-:
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