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08-27-2014, 12:27 PM   #16
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QuoteOriginally posted by micromacro Quote
I quoted you, you told that you did use the flash for bougainvillea.
I was the one who used flash on the Bougainvillea.

08-27-2014, 12:28 PM   #17
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jadedrakerider, me bad. Sorry.
08-27-2014, 07:21 PM   #18
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My K5 does this all the time with magenta and red, especially on flowers on sunny days, and red/pink spotlights at shows. The details are still there if you desaturate. I usually cope by going into Camera Calibration in Lightroom and dropping the red primary saturation by 10-20. Sometimes tilting the red balance to orange by 5-10 brings some of the detail back without sacrificing too much of the color.

Modifying the exposure doesn't usually seem to help much.

Of course, if you're shooting in jpg only, the details are probably lost. Why cripple yourself?
08-27-2014, 08:34 PM   #19
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QuoteOriginally posted by Luuk Quote
because i didn't know then
I think you meant "I didn't know them". American English isn't so easy.

All my work is done with manual exposure. I choose the shutter speed, aperture and ISO setting. It is not difficult to learn but it will require some time for study.

No Euros are required, only your time and attention.

09-01-2014, 02:05 AM   #20
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Have you tried printing it? I've had this effect on a K20D with red and magenta flowers. I turned myself inside out trying to work out what was causing it, only to find that it looked perfectly normal when printed.
09-01-2014, 11:59 AM   #21
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QuoteOriginally posted by narual Quote
My K5 does this all the time with magenta and red, especially on flowers on sunny days, and red/pink spotlights at shows. The details are still there if you desaturate. I usually cope by going into Camera Calibration in Lightroom and dropping the red primary saturation by 10-20. Sometimes tilting the red balance to orange by 5-10 brings some of the detail back without sacrificing too much of the color.

Modifying the exposure doesn't usually seem to help much.

Of course, if you're shooting in jpg only, the details are probably lost. Why cripple yourself?

My investigation indicates the red channel is over exposed by as much as 4 stops, its impossible to tell how much because it looks like at least half the red has been lost and thrown away. Who knows what was originally there.


To a great extent it doesn't matter, the detail is not separately in the colour channels, it is a mixture of green blue and red channel information. Some manufacturers sample edges data in the green channel (the green channel alone holds 50% of the image details). Other manufacturers sample edge changes from all channels.


So when you desaturate the details appear because most are held in the green channel and just about everything is present in all three channels.


Take test images recreate the situation. take one as metered, one 3 stops underexposed one 4 stops and one 5 stops underexposed. Then in post bring the brightness of all to the same level. Then compare them to see if this effect is reduced as I expect it to be.


Ultimately the workaround is likely to be a mixture of underexposure and some red channel enhancement in post, but lets first find out how much underexposure is needed.
09-05-2014, 02:52 PM   #22
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Luuk, thanks for posting this. This has been a very informative thread.
Thanks everyone.

09-06-2014, 12:19 PM   #23
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your welcome. I found this also this very informative
10-08-2017, 10:06 AM   #24
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I hit this issue years ago with my old K-m , got it again yesterday with the K3 . Tried tinkering with the RAW in RawTherapy , and much improved. Looking at what the "errors" were , I have a theory.:

The Bayer uses green as a proxy for "white" (light level)
Now red is directly opposite green on the colour wheel.
So I suspect the JPEG processing in camera is attempting to the "grey level" of the petals up to 50% ...by measuring the green, of which there is almost none.

So the effect is the exposure (&saturation?) get boosted until there is sufficient "green" in the red bits ... which is really way too much red.

---------- Post added 10-08-2017 at 06:46 PM ----------

Raw with default settings: (e.g. camera white balance)



Then adjust tint towards green (only change)



Then add tone mapping

10-10-2017, 12:35 PM   #25
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They're very overexposed. Reds are a problem for that Sony 16 sensor to start with, it's better to underexpose. The effect is a bit of a silk-screen print look.
10-13-2017, 12:24 PM   #26
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QuoteOriginally posted by Luuk Quote
I have no idea how this flower got such a weird
color. The aperture is to be precise 1.9. Someone got
an explanation?
Original on Flickr: The Photocentric | Flickr
You've blown your red channel (badly). Red is hard to photograph.
01-01-2018, 04:51 PM   #27
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I don't know if you want anyone else's 2 cents worth but I think why the color is off, primarily the red, on the original posts could be something to do with how the camera is interpreting the optimum white balance setting for color temperature for the whole frame and not necessarily the primary subject. The Auto White Balance or the white balance setting you are using is possibly processing the temperature to too low a value or into the Blue range.

I am able make fine adjustments in the color temperature with my K70 after changing settings in the camera menu to allow fine temperature compensation adjustments and I expect you can do the same with your K3 as well. Sometimes adjusting the temperature up or down a few hundred degrees K will make a big difference in the final product. If you are able to set the camera to make adjustments in color temperature. The camera will also allow you to to experiment on a sample or the most recent shot taken to find an optimal setting and save the file with the changes in color temperature.

I have also found that you can also adjust the color temperature of a JPG inside Digital Camera Utility 5 or in Photoshop Raw File Editor and by doing so the red & green setting will also change without necessarily becoming over saturated or de-saturated.

Last edited by NS_Sailor; 01-01-2018 at 05:03 PM.
03-03-2018, 10:10 AM   #28
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QuoteOriginally posted by NS_Sailor Quote
I don't know if you want anyone else's 2 cents worth but I think why the color is off, primarily the red, on the original posts could be something to do with how the camera is interpreting the optimum white balance setting for color temperature for the whole frame and not necessarily the primary subject. The Auto White Balance or the white balance setting you are using is possibly processing the temperature to too low a value or into the Blue range.

That is a very good point. I find that my K10D doesn't have great WB presets. The Flash setting is far too cool. I think I will consider a green filter when I am shooting a red object like these so that the detail in the raw is not lost (as it is in my bougainvillea). I wonder how well that would work.
03-03-2018, 06:37 PM   #29
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The next time you see this in review on the camera's LCD, check your color setting (the button to the right of OK) On the K3 this can happen in RAW as well as jpg. If it's set on one of the more vivid setting, this can cause that kind of color blow out, especially in bright sunlight. I've had issue before, so I hope that helps.
08-28-2021, 05:56 AM   #30
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So 7 years from initial post (and about 4 since my last comment) having been playing with some software to process images, I think the "red" issue is correct , but in general "not green" (you may be able to similar with a pure blue, no green component) .

My suspicion is the camera , autofocus & exposure are both processing the "green" channel, so the overall level is boosted until sufficient green is seen. I my case I do spot metering making this even worse. Having had to code this same situation I have some sympathy the develeopers.
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