Okay you gurus, I have some questions about white balance, and I’ll use an example to hopefully make it clearer. I often take nature photos in the woods, and it’s not unusual for my DSLR’s AWB to set the WB to something like 4200K and a tint of -3 or so. The camera sees all the greenish yellow leaves on the trees, reddish yellow leaves on the ground and probably assumes there is a yellowish cast, so it assigns a cooler WB to neutralize the “color cast” it thinks it sees. The result is an overly bluish image, and depending on the amount of green leaves or yellow-red leaves, it adjusts the tint as well. Not very accurate. If I use a gray card and use it to set an “accurate” WB, it forces the card to be perfectly neutral. That’s great for portraits, skin tones, or when you want a specific object in the scene to look more like it would when shot under daylight conditions (I.e., no shady woods to influence the color). However, if the goal is just a photo of the woods themselves, I often find this gray card WB to be overly warm and yellow. I’m guessing that our eyes and brain pick a WB that is somewhere between the above extremes. Perhaps we don’t really see a gray card as perfectly neutral under these conditions, so forcing it to be 0a/0b, may not be the best choice. I did a search on the internet, but didn’t find anything other than the “accurate” gray card method. There’s probably no simple answer, but I thought I’d see what folks on this forum have to say (assuming anyone hangs out here anymore!!). Thanks, Lou
Interesting question… I hope the forum is still ticking over!? Wish I could offer a solution 🫠 ________________________________ From: Louis Dina via colorsync-users <colorsync-users@lists.apple.com> Sent: Friday, November 17, 2023 7:34:04 PM To: colorsync-users@lists.apple.com <colorsync-users@lists.apple.com> Subject: WB Questions Okay you gurus, I have some questions about white balance, and I’ll use an example to hopefully make it clearer. I often take nature photos in the woods, and it’s not unusual for my DSLR’s AWB to set the WB to something like 4200K and a tint of -3 or so. The camera sees all the greenish yellow leaves on the trees, reddish yellow leaves on the ground and probably assumes there is a yellowish cast, so it assigns a cooler WB to neutralize the “color cast” it thinks it sees. The result is an overly bluish image, and depending on the amount of green leaves or yellow-red leaves, it adjusts the tint as well. Not very accurate. If I use a gray card and use it to set an “accurate” WB, it forces the card to be perfectly neutral. That’s great for portraits, skin tones, or when you want a specific object in the scene to look more like it would when shot under daylight conditions (I.e., no shady woods to influence the color). However, if the goal is just a photo of the woods themselves, I often find this gray card WB to be overly warm and yellow. I’m guessing that our eyes and brain pick a WB that is somewhere between the above extremes. Perhaps we don’t really see a gray card as perfectly neutral under these conditions, so forcing it to be 0a/0b, may not be the best choice. I did a search on the internet, but didn’t find anything other than the “accurate” gray card method. There’s probably no simple answer, but I thought I’d see what folks on this forum have to say (assuming anyone hangs out here anymore!!). Thanks, Lou _______________________________________________ Do not post admin requests to the list. They will be ignored. colorsync-users mailing list (colorsync-users@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.apple.com%2Fmailman%2Foptions%2Fcolorsync-users%2Fralphwyatt%2540hotmail.com&data=05%7C01%7C%7Cab216be3339b43167e5a08dbe7a43b99%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638358464776720732%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=KS863HSw6NOiqhba84itHB4znltlZt36EkxPAya9aVI%3D&reserved=0<https://lists.apple.com/mailman/options/colorsync-users/ralphwyatt%40hotmail.com> This email sent to ralphwyatt@hotmail.com
Short answer: ignore the numbers, which has little to do with ‘accuracy’. CCT WB value is rather meaningless anyway. CCT Kelvin defines a large number of possible colors for one. Each raw processor will report differing values from the same raw image as well. I've measured a light source with a Spectrophotometer below, and you can see what it actually measures and what two raw converters report (one being Adobe's) is different. The numbers reported don't really matter; the color appearance in a raw converter and how you want it to appear is essential. http://digitaldog.net/files/CCTandRaw.jpg http://digitaldog.net/files/RawWB_Differences.jpg Andrew Rodney http://www.digitaldog.net/
On Nov 17, 2023, at 12:34 PM, Louis Dina via colorsync-users <colorsync-users@lists.apple.com> wrote:
Okay you gurus, I have some questions about white balance, and I’ll use an example to hopefully make it clearer.
I often take nature photos in the woods, and it’s not unusual for my DSLR’s AWB to set the WB to something like 4200K and a tint of -3 or so. The camera sees all the greenish yellow leaves on the trees, reddish yellow leaves on the ground and probably assumes there is a yellowish cast, so it assigns a cooler WB to neutralize the “color cast” it thinks it sees. The result is an overly bluish image, and depending on the amount of green leaves or yellow-red leaves, it adjusts the tint as well. Not very accurate.
Oh, if you shoot raw (hopefully <g>) you don’t want a gray card anyway. You want a spectrally neutral white 'card' because of the encoding of raw data values. https://photographylife.com/diy-reliable-and-cheap-universal-white-balance-r... JPEG shooter, OK, spectrally neutral gray card (many are not neutral). And clicking to make neutral doesn’t equal accurate or pleasing color. Season to taste. This is, after all, photography. “You don’t take a photograph, you make it.” – Ansel Adams Andrew Rodney http://www.digitaldog.net/
On Nov 17, 2023, at 12:34 PM, Louis Dina via colorsync-users <colorsync-users@lists.apple.com> wrote:
However, if the goal is just a photo of the woods themselves, I often find this gray card WB to be overly warm and yellow.
participants (3)
-
Andrew Rodney
-
Louis Dina
-
ralph wyatt