Pages: 1 [2] 3 4 ... 8   Go Down

Author Topic: The sky is blue - or should be...  (Read 20218 times)

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #20 on: May 02, 2018, 01:36:44 pm »

Not sure why someone is futzing around with an image that isn't the OPs, kind of pointless.
Producing a blue sky from the raw supplied isn't really rocket science:
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

sebbe

  • Full Member
  • ***
  • Offline Offline
  • Posts: 113
Re: The sky is blue - or should be...
« Reply #21 on: May 02, 2018, 02:24:13 pm »

Not sure why someone is futzing around with an image that isn't the OPs, kind of pointless.
Producing a blue sky from the raw supplied isn't really rocket science:

As far as I understand it he is looking after the reason not how to turn the sky blue.

to OP: A lens can have quite an impact on colors. Your picture was shot with an old non sony lens over a mechanical adapter I suppose (no exif about the lens and aperture). And then there is quite som haze as other already mentioned. The sky I very bright then and this can also change the colors. I would add some points on tint towards magenta and also a few kelvins towards yellow. See below.

Reshoot it and use a gray card or LCC-plate to get the right white balance for the scene. Try your test test again.
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #22 on: May 02, 2018, 02:30:41 pm »

As far as I understand it he is looking after the reason not how to turn the sky blue
How NOT to turn the sky blue? I produced a bluer sky. I can produce a lesser blue sky. With the OP's supplied raw. Under exposing any image isn't ideal, we've covered that. But even with the under exposed sky, making it more or less blue isn't rocket science.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #23 on: May 02, 2018, 03:21:10 pm »

Umm, what ? D50 is certainly (one) definition of neutral. Anything sufficiently close to the black body or Daylight locus is neutral. It's the print standard for neutral!

As for what whether a particular display color temperature looks cool or warm, - that rather depends on how neutral and what color temperature other light sources around the display are, and how adapted to the screen white the observer is.

(I routinely run with my display set to D55, and it's certainly neutral.)

I'm not doubting you think your display set to D55 looks neutral to you, but the OP has stated his display set to D50 makes the blue sky image he posted look muddy yellow which doesn't look that way on my display.

Does the blue sky sample image posted by the OP look muddy yellow to you on your D55 calibrated display?


That's the problem with folks associating a color temp number to some hue of neutral for display calibration. At some point the yellowish/orangish hue of D50 compared to D65 is going to contaminate certain colors such as blue sky because clearly ICC display profile matrices and/or LUTs aren't fixing it calibrating to D50 if blue skies look muddy yellow as the OP indicated.

It appears that we all need to stop thinking our display can represent real daylight and just make sure white and gray tones look neutral. Call it D50 or whatever. The number doesn't matter as evident in this thread.
Logged

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #24 on: May 02, 2018, 03:26:04 pm »

Had the photographer(s) not interfered, I think a camera or a photo printing machine might have produced this appearance using “Auto” mode settings.

What is your point with the look you've given those screenshots? Are you saying "Auto" mode favors overly orangy yellow warm daylight? Or that they have a screwed up version of what D50 is suppose to look like?

I have never encountered any printer whose "Auto" mode rendered images that way. Or are you just being funny?
Logged

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #25 on: May 02, 2018, 03:30:23 pm »

As far as I understand it he is looking after the reason not how to turn the sky blue.

to OP: A lens can have quite an impact on colors. Your picture was shot with an old non sony lens over a mechanical adapter I suppose (no exif about the lens and aperture). And then there is quite som haze as other already mentioned. The sky I very bright then and this can also change the colors. I would add some points on tint towards magenta and also a few kelvins towards yellow. See below.

Reshoot it and use a gray card or LCC-plate to get the right white balance for the scene. Try your test test again.

Perfectly rendered. You got the foliage shadow hues just right and the blue sky as well. But you didn't address why the OP is seeing the blue sky as muddy yellow. Anyone can render someone else's image to look right but that's not the OP's problem.
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #26 on: May 02, 2018, 03:38:40 pm »

I'm not doubting you think your display set to D55 looks neutral to you...
You're not reading or comprehending the facts presented to you (again). You're again confused by color perception and color appearance! And you didn't read the facts:
D50 is certainly (one) definition of neutral. Anything sufficiently close to the black body or Daylight locus is neutral.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #27 on: May 02, 2018, 03:39:56 pm »

Anyone can render someone else's image to look right but that's not the OP's problem.
I'm pretty certain both concepts are wrong. Certainly the first is!
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Doug Gray

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2197
Re: The sky is blue - or should be...
« Reply #28 on: May 02, 2018, 03:44:34 pm »

I'm not doubting you think your display set to D55 looks neutral to you, but the OP has stated his display set to D50 makes the blue sky image he posted look muddy yellow which doesn't look that way on my display.

Does the blue sky sample image posted by the OP look muddy yellow to you on your D55 calibrated display?


That's the problem with folks associating a color temp number to some hue of neutral for display calibration. At some point the yellowish/orangish hue of D50 compared to D65 is going to contaminate certain colors such as blue sky because clearly ICC display profile matrices and/or LUTs aren't fixing it calibrating to D50 if blue skies look muddy yellow as the OP indicated.

It appears that we all need to stop thinking our display can represent real daylight and just make sure white and gray tones look neutral. Call it D50 or whatever. The number doesn't matter as evident in this thread.
Most likely the problem isn't the ICC display profiles but partial adaptation when using monitors with different whitepoints. It can take many minutes to get adapted when changing monitors or different whitepoints on the same one and if you switch using the same image then colors seem off. This gets a bit locked in one's mental image.  When switching whitepoints one should do other computer work for 10 minutes or so before looking at images. That's why it's best to stick with just one whitepoint. Most select a monitor white point that most closely matches a near hard proof station so that physical prints will look close to the same on the monitor using soft proof.
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #29 on: May 02, 2018, 03:50:43 pm »

Most likely the problem isn't the ICC display profiles but partial adaptation when using monitors with different whitepoints. It can take many minutes to get adapted when changing monitors or different whitepoints on the same one and if you switch using the same image then colors seem off. This gets a bit locked in one's mental image.  When switching whitepoints one should do other computer work for 10 minutes or so before looking at images. That's why it's best to stick with just one whitepoint. Most select a monitor white point that most closely matches a near hard proof station so that physical prints will look close to the same on the monitor using soft proof.
What Tim doesn't seem to understand in GWGill's factual post is that what looks/appears neutral and is neutral are not the same. If he puts on rose color glasses, anything he thinks is neutral (D55, D50 etc) while being neutral doesn't appear neutral. What Tim wrote was simply wrong: you've admitted you prefer D50 display which isn't a neutral white.
The reason there's so much ignorance on the subject of color management, is that those who have it are so eager to regularly share it! - The Digital Dog
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #30 on: May 02, 2018, 03:50:52 pm »

Most likely the problem isn't the ICC display profiles but partial adaptation when using monitors with different whitepoints. It can take many minutes to get adapted when changing monitors or different whitepoints on the same one and if you switch using the same image then colors seem off. This gets a bit locked in one's mental image.  When switching whitepoints one should do other computer work for 10 minutes or so before looking at images. That's why it's best to stick with just one whitepoint. Most select a monitor white point that most closely matches a near hard proof station so that physical prints will look close to the same on the monitor using soft proof.

You still didn't explain why the OP is seeing the blue sky as a muddy yellow. He states clearly that the initial preview on his Eizo (he's already adapted to) and is his go to reference for neutral D50 as an editing workstation says the blue sky look muddy yellow. That's a huge shift that can't be explained with adaptation. I have a mix of different hues of light all around my workstation display and I NEVER see blue skies look that way in ANY of my images.

There's something messed up with the OP's display if it makes blues skies look that bad!
Logged

Doug Gray

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2197
Re: The sky is blue - or should be...
« Reply #31 on: May 02, 2018, 03:55:31 pm »

You still didn't explain why the OP is seeing the blue sky as a muddy yellow. He states clearly that the initial preview on his Eizo (he's already adapted to) and is his go to reference for neutral D50 as an editing workstation says the blue sky look muddy yellow. That's a huge shift that can't be explained with adaptation. I have a mix of different hues of light all around my workstation display and I NEVER see blue skies look that way in ANY of my images.

There's something messed up with the OP's display if it makes blues skies look that bad!

Could be something wrong in his process. I opened the RAW file in Photoshop and the sky looks pretty much what I would expect and I use D50 whitepoint.  If that happened to me I would measure the Lab reading from the monitor and compare it to samples from the image in the same area.
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #32 on: May 02, 2018, 03:55:52 pm »

I have a mix of different hues of light all around my workstation display and I NEVER see blue skies look that way in ANY of my images.
You've apparently got color perception issues because you told us that Magenta 'is an invisible hue'. That's of course simply nonsensical to anyone here who actually understands color.
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Doug Gray

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2197
Re: The sky is blue - or should be...
« Reply #33 on: May 02, 2018, 04:06:25 pm »

You've apparently got color perception issues because you told us that Magenta 'is an invisible hue'. That's of course simply nonsensical to anyone here who actually understands color.

I guess you just haven't profiled a CYK printer recently.   ;)
Logged

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #34 on: May 02, 2018, 04:06:29 pm »

Could be something wrong in his process. I opened the RAW file in Photoshop and the sky looks pretty much what I would expect and I use D50 whitepoint.  If that happened to me I would measure the Lab reading from the monitor and compare it to samples from the image in the same area.

That might explain it, Doug. But an Eizo is a pretty reliable display and the OP isn't a slouch when it comes to wanting to be precise about his calibration and profiling so I'm thinking it might be attributed to what the Raw converter is doing under the hood with how it renders ICC managed previews. Maybe he's only seeing a yellowish hue for that particular blue and the rest looks normal. But it is a screengrab he posted and I don't see any muddy yellow.

And to any nimrod that posts the plankian locus showing where D50 falls within the area of neutrality, I've got about 5 different versions of this locus and it places D50 way over in the warm region, so just stop posting those useless idiotic, worthless maps. Just looking at how different all of them are to what is warm verses cool makes me want to ring the neck of a the color scientists that make these stupid maps.
Logged

Hening Bettermann

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 945
    • landshape.net
Re: The sky is blue - or should be...
« Reply #35 on: May 02, 2018, 04:07:41 pm »

Uff what a discussion I triggered! Thanks to all who chimed in. I'll present the result of my own fiddling before I study your posts more closely.
There is no way I can achieve a satisfactory result in RawTherapee. I get my best result with an adjustment layer 'Color Balance' in PhotoLine. However, the histogram becomes jaggy. 

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #36 on: May 02, 2018, 04:14:49 pm »

I guess you just haven't profiled a CYK printer recently.   ;)

I'm glad you brought that up because it is an invisible hue when when mixed with a bluish looking daylight image especially with a magenta hued blue sky. How much yellow should be seen in green foliage lit by a noon day sun on a clear day? How warm does the sun make natural objects look no matter whether they are cool or warm toned? To get a convincing daylight appearance it helps to take note how much magenta is in sky blue.

For example stare at the second image I posted (not the flotube WB top version) and then look at a neutral gray area on your display. What hue has it turned into? On my display it makes ACR's neutral R=G=B surround take on a muddy greenish yellow tint. Not too pronounced but very subtle. But note you can't really see magenta in the green foliage or warm concrete. Sample the skin tones and the Lab reading favor a orangish yellow hue and have tint slider in ACR set to +30.
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: The sky is blue - or should be...
« Reply #37 on: May 02, 2018, 04:18:55 pm »

I guess you just haven't profiled a CYK printer recently.   ;)
Oh I have. Doesn’t back up Tim’s ridiculous and utterly wrong idea that Magenta is an invisible hue! Where does he come up with these flat earth ideas?
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #38 on: May 02, 2018, 04:20:11 pm »

That magenta crack was by Andrew. Sorry, Doug, my mistake. It's clear Andrew hasn't edited very many daylight images seeing he isn't a photographer any longer and is just a technology writer.

Magenta is a nasty hue especially when rendering in ACR using Knoll's color engine which provides a very pure hue of this magenta that if applied in the right amount creates perfect renditions of blue skies that I take visual notes on when I photograph my local park. Daylight changes hue in this town and there are a myriad of beautiful blue sky color I want to capture and faithfully render.
Logged

Tim Lookingbill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2436
Re: The sky is blue - or should be...
« Reply #39 on: May 02, 2018, 04:24:08 pm »

Uff what a discussion I triggered! Thanks to all who chimed in. I'll present the result of my own fiddling before I study your posts more closely.
There is no way I can achieve a satisfactory result in RawTherapee. I get my best result with an adjustment layer 'Color Balance' in PhotoLine. However, the histogram becomes jaggy.

Hening, are you seeing how cyanish green that entire image looks or are you still seeing the blue sky a muddy yellow? I'm not seeing it in Firefox browser which is color managed.
Logged
Pages: 1 [2] 3 4 ... 8   Go Up