blue skies color casts

[larkis]

Is there a good technique someone uses for recognizing unnatural color casts in blue skies ? I have noticed that vision seems to adjust to certain color casts and one needs to "reset" to a reference colour in order to see contaminating colours that don't necessarily belong. For example I'm working with some imagines that have overcast cloudy skies that lightroom (or the camera sensor) tends to skew a little bit towards purple. Obviously recognizing this becomes difficult at times. I use a calibrated Eizo display, a Macbeth light booth for viewing my prints and a colour checker passport (most of the time) as a reference when shooting.

I do realize color is very much in the eye of the beholder, but I'm always looking for some tips and tricks others have found useful. I'm also not a color scientist or a "replicate what was there" type of guy, but like to hit certain "notes" in order to have relatively believable images.

[Martin Kristiansen]

Colour of sky's is a personal bugbear of mine. I think you might be having the same issues that I have. I get these sky's that I think of as magenta. Sounds. Bit like your purple. On my Leaf I found that creating a profile with the dng profile editor pretty much sorted things out. For a quick fix I go into selective colour and on the blues I reduce magenta.

Anyway that's how I deal with the issue. Your question was how do I recognize it and for that all I can say is I look for it. If I'm not sure I pull magenta out of the sky's and see how a I feel about it. On a few occasions I have over done it and had odd looking cyan sky.

Hope that is some help.

Lovely images on your blog by the way.

[TonyW]

In this sort of case it may be of help to first make the image look worse to more clearly identify unwanted casts.  

One way may be to temporarily boost Saturation and maybe even Vibrance to maximum first as it may aid in your image evaluation.  Next remove the offending cast using the HSL tab to fine tune the colour (being aware of the effect it will be having on the rest of the image) then reset your Sat and Vib back to 'normal' for your image

[Slobodan Blagojevic]

... For example I'm working with some imagines that have overcast cloudy skies that lightroom (or the camera sensor) tends to skew a little bit towards purple...

What white balance? Daylight, Shade and Cloudy all come with +10 magenta by default. If you want Daylight without magenta, just use Flash.

In Camera Calibration, there are several Profiles (camera specific), so try Neutral to see if it helps.

[robgo2]

What white balance? Daylight, Shade and Cloudy all come with +10 magenta by default. If you want Daylight without magenta, just use Flash.

In Camera Calibration, there are several Profiles (camera specific), so try Neutral to see if it helps.

I agree that white balance and camera color profile are crucial.  Not all raw convertors perform these functions well.  Also, it is worth pointing out that sometimes skies are slightly pink, especially around sunrise and sunset.  At those times, don't fight it, use it.

Rob

[JRSmit]

Color cast visible in Lightoom or only on prints? Or on both?
How do you set the white balance?

[larkis]

It's both, I think my monitor and what I get out of the printer are close, or as close as I can get them given my basic knowledge of profiles and calibration compared to some members here. I do check the prints in a light booth as well. (examples of my setup are bellow)

The issue is that my camera tends to add a little bit to much purple to skies and it takes seeing a "proper" sky to notice how much purple there actually is. I guess the best strategy would be to have a good reference image, or a set of reference images to compare against. My original question was more about best practices for identifying colour casts in situations where human vision adjusts to ignore them.