# Reds



## bholliman (May 16, 2015)

I sometimes struggle to get reds to look "right" out of my 6D and 5D MkIII. Attached is a recent picture of some bright red tulips taken with my 6D and 135L lens. I tried different profiles in Lightroom and played with red and green hue, saturation and luminescence, but the red color doesn't match the color I remember seeing. I ended up using the neutral profile, which comes closest to my recollection. I have not tried setting up my own profiles yet.

Anybody else experiencing these problems? Any suggestions on how to correct?

Thanks


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## Jim Saunders (May 16, 2015)

I have, absolutely; a Colorchecker Passport (here) is a big help.

Jim


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## bholliman (May 18, 2015)

Jim Saunders said:


> I have, absolutely; a Colorchecker Passport (here) is a big help.
> 
> Jim



Thanks Jim. I'll pick one of these up.


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## bluemoon (May 18, 2015)

something else to think of, we are unable to remember colors. Our brain is just no wired that way. There are some exceptions to the rule, but they are few and far between. . . I work with colors in my daily job and have learned that my memory tricks me often and now have Pantone books in strategic locations. 

pierre


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## NancyP (May 19, 2015)

I consider that I have a good memory for color as used for color-matching garments, and I make mistakes occasionally. Keeping a consistent color memory is not something that we humans are set up to do.


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## gbchriste (May 19, 2015)

I have a red/green color deficiency so relying on my eyes and memory for correct color is not an option. But as a portrait shooter, getting correct color balance is crucial so my subjects don't come out looking like Smurfs or Devils. While the camera presets can get you close for non-critical photos, if you want to really nail the colors you need to be employing a color managed workflow that begins in the camera.

Some might take the easy route and use the Color Picker in Lightroom to click on a supposedly white patch in the image to set a neutral white balance but I've found this very unreliable.

Instead, I use a Lastolite EzyBalance to do a custom in-camra white balance.

http://www.amazon.com/Lastolite-LL-LR1250-12-Inch-Ezybalance/dp/B0009QZDL6

I like the 12" model because it's large enough to fill up the view finder when I'm taking my shot for balance, and small enough to fold up nice and neat and slip in to my back pocket. I reset the custom in-camera white balance ever time me and my subject move in to different lighting. When shooting in the golden hour I'll rebalance very few minutes even if we aren't moving to accommodate the rapidly changing ambient light.

Using this approach I get spot on, perfectly neutral colors on every frame. That gives a good baseline them from which to edit for the effect I want, which usually means just adding a bit of warmth with the Lightroom Temp slider.


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## AcutancePhotography (May 19, 2015)

I am glad I am not the only one. Recently I took, what I thought would be, some nice pictures of Tulips. They did not turn out as well as I thought. Tulips are surprisingly tough to photograph well.


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## d (May 19, 2015)

As another has suggested, a Colorchecker Passport will go a long towards improving colour accuracy from your camera. A grey card won't fix it - while it will give you a neutral starting point, different camera models vary in their colour response. Profiling with something like the CC Passport will correct much of an uneven or inaccurate colour response. I work in a photography studio, and recently used the CCP to profile a 5D MkIII, and was very surprised at how far of some colours were SOOC.

Cheers,
d.


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## Marsu42 (May 19, 2015)

bholliman said:


> I sometimes struggle to get reds to look "right" out of my 6D and 5D MkIII.



I suspect a user error, the 6d gives spot-on, vivid and beautiful colors if used properly.

For further analysis post the raw file as talking about some cooked jpeg is nearly useless.



d said:


> As another has suggested, a Colorchecker Passport will go a long towards improving colour accuracy from your camera. [...] I work in a *photography studio*, and recently used the CCP to profile a 5D MkIII, and was very surprised at how far of some colours were SOOC.



I have it and it's great - in *constant* lighting.* Outdoors*, it's nearly useless if you don't re-shoot the card every other minute as the lighting is so quick to change (sun moving, clouds and moisture changing the wb).


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## fish_shooter (May 19, 2015)

UV could be a problem as well. Many flowers reflect UV light to guide insects, which they can see but we can't. There may be enough UV light getting through your lens (minimized by design) to affect the image. Film and sensors are sensitive to UV light.


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## d (May 23, 2015)

Marsu42 said:


> bholliman said:
> 
> 
> > I sometimes struggle to get reds to look "right" out of my 6D and 5D MkIII.
> ...



Its design lends itself towards being easy to reshoot regularly in changing conditions when outdoors and on location - that's the main reason why I purchased it. You may as well complain about cameras being "nearly useless" if you don't constantly update its exposure settings when shooting in fast changing conditions!

Remember it doesn't just allow you to correct white balance - it's also adjusting the native colour response for a given camera across a range of colours, which among other things is determined by CFA characteristics and camera processing, and are effectively constant within the camera. If the OP is concerned about colour accuracy outdoors, making a couple of CCP profiles for their 6D under different conditions (bright sunlight, overcast, sunset etc) should go most of the way towards addressing the 6D's particular colour biases. WB is only one part of the equation.

d.


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## slclick (May 23, 2015)

Is this an issue of digital sensors having a tendency to blow the red channel?


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## danski0224 (May 23, 2015)

bholliman said:


> I sometimes struggle to get reds to look "right" out of my 6D and 5D MkIII. Attached is a recent picture of some bright red tulips taken with my 6D and 135L lens. I tried different profiles in Lightroom and played with red and green hue, saturation and luminescence, but the red color doesn't match the color I remember seeing. I ended up using the neutral profile, which comes closest to my recollection. I have not tried setting up my own profiles yet.
> 
> Anybody else experiencing these problems? Any suggestions on how to correct?
> 
> Thanks



You may want to try a custom white balance. I have used Clear White once in a while, and I should use it more often: http://www.digitalphotographykits.com/

I think the green in the foreground of your picture is messing up auto white balance.

If nothing else, I have had to really watch the RGB histogram for clipping in any channel, red and blue for sure and dial it back as necessary. Sometimes, there are 2 spikes and you will miss the second one if you don't look for it. I have found that DPP "Auto Tone" will work wonders by itself for these somewhat underexposed images.

I have a Canon 4.2mp 1D and that one does well with reds- possibly due to the CCD sensor, but it is only 4.2 mp, so no latitude for cropping. Nor does it have AFMA, which also sucks.

The 1D bodies seem to be much better with auto white balance.


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## Marsu42 (May 23, 2015)

d said:


> Marsu42 said:
> 
> 
> > I have it and it's great - in *constant* lighting.* Outdoors*, it's nearly useless if you don't re-shoot the card every other minute as the lighting is so quick to change (sun moving, clouds and moisture changing the wb).
> ...



Fair enough, in that case let's just say I underestimated how fast and decisive lighting changes outdoors, not only by ambient lighting over time but simply with the direction you point your camera to. So anyone who wants to do color calibration outside with this method should be ready to generate lotsa dng profiles.

That doesn't change my opinion 'bout the op's "red" shot though, with proper handling of the 6d it shouldn't be necessary to use a color checker to avoid the nuclear holocaust look of those flowers.


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## danski0224 (May 23, 2015)

Marsu42 said:


> That doesn't change my opinion 'bout the op's "red" shot though, with proper handling of the 6d it shouldn't be necessary to use a color checker to avoid the nuclear holocaust look of those flowers.



Looks like harsh lighting- could have used a shade.

I would bet that the image as a whole is overexposed. For sure, the red channel is all the way right. I would guess that the exposure compensation should have been at least -1 if not -1.5.

A circular polarizer would have helped a great deal.

The image as-is might look decent in B&W. I have a few that look bad in color but great in monochrome.


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## d (May 23, 2015)

Marsu42 said:


> d said:
> 
> 
> > Marsu42 said:
> ...



The image in question is obviously shot around the middle of the day, given the harshness of the light and direction of the shadows. It's not rapidly changing light, unless an odd cloud or two is passing by the sun from time to time. Assume the OP is wanting a nice shot of the tulips with accurate colours - meter off the CCP's grey panel to get a correct exposure (even set a custom WB in camera if you feel like it), snap a shot of the colour chips for making a profile later on, then shoot away. Might take all of 30 seconds at a casual pace. *If* it becomes overcast, you might repeat the process just in case and to get a new WB reference from the grey chip, but apart from that there's no need to be making more CCP profile shots each time you change shooting angles/position.

It's really not rocket science, doesn't take much time at all, and removes pretty much all the guesswork regarding exposure and colour response.

d.


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## Marsu42 (May 23, 2015)

d said:


> Might take all of 30 seconds at a casual pace.



I really do like the ccp, but I'm mostly shooting animals (live animals, that is) because I wanted to get the gray-ish fur right. But after 30 seconds waiting time while holding a color checker in front of their noses, well ... it's all nice and accurate colors for sure, but for the motive - not so much :->

Unfortunately as written, some general dng profile doesn't suffice, it has to be of the very lighting and camera angle. But for inanimate objects like the red flowers, esp. if it's an important or tricky shot, a ccp surely will work just fine and you don't even need photography experience to use it.


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## DFM (May 23, 2015)

Marsu42 said:


> * Outdoors*, it's nearly useless if you don't re-shoot the card every other minute as the lighting is so quick to change (sun moving, clouds and moisture changing the wb).



The _spectrum_ of sunlight is absolutely constant - by definition it is a black body radiator with CRI 100. Clouds are effectively color neutral except in major pollution zones, and the scatter from the sky serves to alter the color temperature of 'daylight' by increasing the blue bias, but it doesn't change - even at night, the sky is the same color of blue, as you can see if you take long-exposure photos under a full moon. The CRI is always 100, even at sunset.

The CCP/Macbeth chart is all about profiling the sensor's _relative_ luma/chroma offsets, it is sensitive to low-CRI spectra such as an LED with a chunk of yellow missing, but the response is effectively immune to color temperature over the range of values you'll get under what we call 'daylight'. You can build one CCP profile for each camera in daytime conditions - sunny, cloudy, foggy, makes no difference - and for any other photo you simply need to fix the WB with a gray reference or one of the standard values. There is no need to wave a CCP in front of every scene. There's a reason your cameras have a WB control and a picture profile called "Neutral", but not one called "Sunny Neutral". You're adjusting entirely different things.


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## agierke (May 23, 2015)

bholliman said:


> I sometimes struggle to get reds to look "right" out of my 6D and 5D MkIII. Attached is a recent picture of some bright red tulips taken with my 6D and 135L lens. I tried different profiles in Lightroom and played with red and green hue, saturation and luminescence, but the red color doesn't match the color I remember seeing. I ended up using the neutral profile, which comes closest to my recollection. I have not tried setting up my own profiles yet.
> 
> Anybody else experiencing these problems? Any suggestions on how to correct?
> 
> Thanks



In photography, the compliment color to red is Cyan, not green. So if you want to tone down reds you need to adjust the cyan slider for reds in LR.


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## Marsu42 (May 23, 2015)

DFM said:


> You can build one CCP profile for each camera in daytime conditions - sunny, cloudy, foggy, makes no difference - and for any other photo you simply need to fix the WB with a gray reference or one of the standard values. There is no need to wave a CCP in front of every scene.



Nice theory from an armchair approach, but doesn't work for me (if it would be correct, I could go 'round shooting the ccp and always get the same profile, but I don't).

The scatter effect of clouds is so strong the the wb is way off in my experience - this might not affect a neutral gray patch so much, but I find it to be significant for the color card. And of course there's the radiance effect of any objects nearby like green leaves or brown trees that has a significant effect on local colors.


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## jrista (May 23, 2015)

bluemoon said:


> something else to think of, we are unable to remember colors. Our brain is just no wired that way. There are some exceptions to the rule, but they are few and far between. . . I work with colors in my daily job and have learned that my memory tricks me often and now have Pantone books in strategic locations.
> 
> pierre



I'd like to see the scientific papers that explain how and why this could be true. I remember colors quite clearly myself for a good while. It is only after years as memories naturally fade, and our recollection of all details, not just color, diminishes. There have been a few papers written on the subject of memory and color, and the science demonstrates that we actually remember things better when they are in color, particularly NATURAL colors, vs. when they lack color, or are artificially colored. 

In that context, I can easily understand the OP seeing the red as his images are being replicated by LR, and not remembering the color of the real flowers that way. The real flowers obviously have natural color, whereas the rendition of those flowers in LR is less natural. That discrepancy, and the OP's sensation of it, more than anything else here, is absolutely real. The closer the OP can get his flowers to render like the real natural color, the less he will feel that something is off. 

There are limitations with rendering realistic color when it comes to digital photography. For one, silicon is extremely sensitive to red and infrared light. To attenuate this sensitivity, camera manufacturers use IR cutoff filters that have a gradual incline in the passband as it enters the reds. This limits how well we can naturally resolve reddish colors. Further, most computer screens are 8-bit sRGB, and the sRGB gamut is a rather limited one. It does not allow the greatest extent for deeper reds. Combine that with potentially limited or incorrect recording of reds by the camera sensor, especially for brighter colors that may be close to the non-linear shoulder of the sensor's response (i.e. closer to the clipping point of the signal), and getting realistic reds can be very difficult.



Calibration with a color checker card is one way to improve results. I wouldn't call it a panacea, but it can help when your working with extreme colors. Keeping your exposure in the linear range of the sensor will also help. That usually means reducing the exposure a little bit, which might hurt shadow detail if you have any...but it will preserve more accurate colors at the high end of the signal.

Manual tweaking of colors with the color channel sliders in LR can do a lot, but it works best if all of your channels are sufficiently below the clipping point of the signal. You need some headroom to shift colors around without unnatural casts appearing.


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## martti (May 24, 2015)

DFM said:


> Marsu42 said:
> 
> 
> > * Outdoors*, it's nearly useless if you don't re-shoot the card every other minute as the lighting is so quick to change (sun moving, clouds and moisture changing the wb).
> ...



Hm. Theoretically maybe so.
In practice you see the color of the light change when clouds pass...there is less blue coming from the sky above if there is a white cloud above. If the cloud is in front of the sun and you have blue sky above, of course you get more blue light in. If you are in a forest, the relative amount of green sieving through the foliage as well as its hue varies according to sunlight. Shiny green leaves look blue when they reflect the blue sky above.

Theories are there to simplify reality so it becomes accessible to rational thinking.
Which is good, I suppose.


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## DFM (May 24, 2015)

martti said:


> Hm. Theoretically maybe so.
> In practice you see the color of the light change when clouds pass...there is less blue coming from the sky above if there is a white cloud above. If the cloud is in front of the sun and you have blue sky above, of course you get more blue light in. ...



... which changes the color temperature but does NOT degrade the CRI. It's a white balance effect only. If it wasn't, then the way the WB pickers operate in Lightroom or Photoshop would be invalid - we would have to apply a different spectral LUT for every Kelvin value.

If you were mixing daylight and artificial light (e.g. in a stadium), or shooting through a strong colored filter, then you would be introducing discrete spectral peaks and troughs, reducing the CRI, and changing the calibration profile.


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## martti (May 24, 2015)

DFM said:


> martti said:
> 
> 
> > Hm. Theoretically maybe so.
> ...



Hm. Theoretically so. It just so happens that when you take pictures of a person while you are walking with her in the shades of trees and bushes you might get her face all green if you do not watch out. Green is not a temperature, it is a color or a hue. You can take pictures of green things under various color temperatures and they remain green. But if the light falling on your model's face is green (sifted through the foliage) no amount of temperature adjustment will ever get it back to normal skin color again. Now you have to do something to take the green hue away. Like a fill-in flash if you do not mind the artificial look it gives to your shot.
Or locally adjusting the amount of green in PP.

If you have a grey card in your shot next to the face and you smartly use the color picker to put your color balance right, you end up with magenta trees. If that's what you like, OK. 

You see?


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## martti (May 24, 2015)

jrista said:


> bluemoon said:
> 
> 
> > something else to think of, we are unable to remember colors. Our brain is just no wired that way. There are some exceptions to the rule, but they are few and far between. . . I work with colors in my daily job and have learned that my memory tricks me often and now have Pantone books in strategic locations.
> ...



Our sensory system is not only analog but relative as well. It has not evolved to give exact values aroud certain zero point along graduated axes but rather bright-dark, warm-cold, pressure-lightness etc. Rough and ready is what is needed for survival!

Our vision gets calibrated according to the ambient light so that we see green as green and red as red whether it is sunlight or candlelight around us. In moonlight, however our cones cease to function and we only see in BW. that's why all the cats are grey in the dark. They do not change color but our machinery or perception changes the way we see them. That's because rods are more sensitive to light...it is better seeing BW than not seeing anything at all.

All this is very basic physiology known for decades now.
We cannot remember the amount of light, we cannot know the weight of a bag of grain unless we either weigh it or have a bag of known weight at hand so we can tell if the other one is lighter or heavier. We cannot asses the volume of a sound and only very few of us have perfect pitch...they can tell whether a note is a C or a C# just by the ear...for some reason a lot of native Mandarine Chinese have perfect pitch but nobody knows why.

Mathematics is basically music with ice cubes in it. 

Color vision is very interesting as well. For instance whales have lots of sensors for blue light on their retina.
That's because they have dwelled in the oceans for so long. Seals, on the other hand who are close relatives to bears, have similar retinal sensors as their terrestial cousins.

Women (some of them) have two different variations of red sensors on their retinae.
Because their speciality was to judge whether a fruit was at its optimum ripeness for picking.

The point is: Do not argue with your wife about the color balance of the pictures you have taken of her.
She is better equipped than all the Adobe males bunched together in this very matter!


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## martti (May 24, 2015)

And still another point: A flower does not have a natural color. this is a nonsensical statement. The pigments in a flower reflect and absorb the spectrum (=the combination of different wavelengths) of the light that is falling on them...and not only that because we only talk about the what we can see which is a very limited part of the spectrum that we antropomorphically call 'visible light'.

Of course a bee or a snake would define 'visible light' differently...


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## jrista (May 24, 2015)

martti said:


> And still another point: A flower does not have a natural color. this is a nonsensical statement. The pigments in a flower reflect and absorb the spectrum (=the combination of different wavelengths) of the light that is falling on them...and not only that because we only talk about the what we can see which is a very limited part of the spectrum that we antropomorphically call 'visible light'.
> 
> Of course a bee or a snake would define 'visible light' differently...



Within the context of human vision, which sees wavelengths from about 750nm through 380nm (the visible spectrum, as it is scientifically defined, and in contrast to the near infrared or near ultraviolet spectrums that bound it), flowers absolutely do have a natural color. It is human vision we are talking about, not bee or snake vision. 

Natural color is colors that occur in nature, and are "appropriate" for the given subject, within the context of human vision and experience. In contrast, a total lack of color would be grayscale or monochrome of some kind. False color would be when colors do not conform to the natural distribution (i.e. green flowers with red stalks and leaves.) 

As I said, there have been scientific studies on this subject.


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## martti (May 24, 2015)

*fail*

No. No 'natural color' but just a part of the spectrum of ambient light absorbed and reflected and observed with the human visual system. Your thinking is wrong.
Get acquainted with the science of vision before you make arguments about it.


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## jrista (May 24, 2015)

*Re: fail*



martti said:


> No. No 'natural color' but just a part of the spectrum of ambient light absorbed and reflected and observed with the human visual system. Your thinking is wrong.
> Get acquainted with the science of vision before you make arguments about it.



Your entirely missing the point, but that isn't surprising on these forums. Why not do a couple searches and read some of the articles I am talking about? Your talking spectrum, I'm talking psychology. *Missing the point*. (Why does everyone around here miss the point 99% of the time? Meh.)


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## danski0224 (May 24, 2015)

Has anyone posting in this topic tried UniWB?

I have not yet, but would like to.


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## jrista (May 24, 2015)

danski0224 said:


> Has anyone posting in this topic tried UniWB?
> 
> I have not yet, but would like to.



I tried UniWB on my 7D a long time ago. I found it unnecessary, as the white balance setting in the camera is simply metadata added to the image. It does not actually affect the exposure of individual green pixels, since all in-camera white balance occurs after the sensor is read out. The only potential benefit with UniWB is that it might prevent the camera from overexposing one channel if your using some kind of automatic or semi-automatic exposure mode (P, Av, Tv) that relies on in-camera metering, but that is it. It does not actually change white balance, since white balance in RAW is simply a bit of metadata and some math.


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## danski0224 (May 24, 2015)

The more accurate RAW histogram is why I want to try it.


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## Marsu42 (May 24, 2015)

danski0224 said:


> The more accurate RAW histogram is why I want to try it.



You gotta be kidding me - unless you are on 1d why fuss around with a hack if Magic Lantern gives you an actual raw histogram, all nice with even an estimation of how much dr was clipped?


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## jrista (May 24, 2015)

Marsu42 said:


> danski0224 said:
> 
> 
> > The more accurate RAW histogram is why I want to try it.
> ...



Totally agree here...use ML for the RAW histogram. Much better than UniWB.


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## danski0224 (May 25, 2015)

Unfortunately, ML doesn't work on 1D bodies.


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## martti (May 25, 2015)

*Re: fail*



jrista said:


> martti said:
> 
> 
> > No. No 'natural color' but just a part of the spectrum of ambient light absorbed and reflected and observed with the human visual system. Your thinking is wrong.
> ...



WHo do you think you are fooling?
You do not know what the point is so you do not have one.
Psychology...give me a break. You know nothing about it!


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## jrista (May 25, 2015)

*Re: fail*



martti said:


> jrista said:
> 
> 
> > martti said:
> ...



Ah, _bluster_. The hallmark of the man without an argument. Nice meeting you, martti. You'll fit right in here. Your a pea in the pod.


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## bholliman (May 26, 2015)

danski0224 said:


> Marsu42 said:
> 
> 
> > That doesn't change my opinion 'bout the op's "red" shot though, with proper handling of the 6d it shouldn't be necessary to use a color checker to avoid the nuclear holocaust look of those flowers.
> ...



I hadn't checked this thread in awhile and was surprised to see it had grown to 3 pages. 

I know this picture isn't very good. It was one of a few quick shots I took while walking through the garden with my wife during a short stop while traveling. Yes, its full, late afternoon sun. Not only is the light less than ideal for good flower photography, but I should have stopped down further so the fountain behind the tulips was not so out of focus. Since we didn't have much time, and my wife little patience for photography I just took a few quick unplanned shots. If this garden were closer to home, I would have shot it in better light and more carefully composed the shot.

I used it as an example since I've seen these messed up reds before. Always in full sunlight, so maybe its just poor technique on my part. That said, shouldn't I be able to get good color rendition in full sun? 

Looking at the raw histogram in Lightroom when I reset it, the exposure looks OK and I don't see major problems with the histogram. None of the color channels have highlights clipped. Blue is clipped in the shadows.

I can make the RAW file available to anybody who wants to play with it, but not sure how to transfer a file this large.

BTW, the settings for the shot are:

ISO 100
1/320
f/5.0


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## danski0224 (May 26, 2015)

bholliman said:


> I used it as an example since I've seen these messed up reds before. Always in full sunlight, so maybe its just poor technique on my part. That said, shouldn't I be able to get good color rendition in full sun?



I would try a custom white balance.

This is easy to use, inexpensive for photography gear and straightforward: www.digitalphotographykits.com

I have noticed that it really makes a noticeable difference. I haven't used it much, but the results I get are telling me that I need to make the effort to use it more.

Also try a circular polarizer- plenty of light in full sun.

Digital cameras have UV filters, so I don't know if there are additional issues any possible UV reflection from the flowers requiring an additional UV filter. 

You may need to dial in some negative exposure compensation. Try it, it can't hurt.


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## bluemoon (May 26, 2015)

jrista said:


> bluemoon said:
> 
> 
> > something else to think of, we are unable to remember colors. Our brain is just no wired that way. There are some exceptions to the rule, but they are few and far between. . . I work with colors in my daily job and have learned that my memory tricks me often and now have Pantone books in strategic locations.
> ...



Sorry, no papers, but here's what I have read and what seems to be going at my work. 
As explained by martti, our vision system is relative rather than absolute. When we try to memorize the colors, we mentally compare them to something we know or describe them as a warm red, darker than something else and so on. We are creating a reference point that can be used for later recognition.
try this, have somebody make you 10 squares of various red color. pull one out of the hat and mark the back. Look at the color and try to memorize it without rationalizing its hue, saturation or brightness. Put it back in the hat and have the person helping you lay them out on the table next day. See if you can pick the right one. If you concentrate on the color alone without making mental references to it being dark, light, warm, cold and so on, it is very unlikely that you'd be able to pick the right square. 

let me know how it goes!

pierre


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## privatebydesign (May 26, 2015)

A very large portion of jpeg compression comes from the fact that human vision is notoriously insensitive to colour. That is why compression algorithms convert RAW sensor data to the YCbCr colour space, to separate out luminance (Y) from colour (CbCr), the human eye is much more sensitive to detail, luminosity variation, than colour and the colour component can be compressed much more than the luminosity and still retain more information than the human eye can discern at normal viewing distances.


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## Dick (May 26, 2015)

I have faced the problem with reds, unfortunately.

I'm having serious problems with reds these days. My daughters often have red clothes on and the photos taken require lots of PP to fix the red channel issues. Working with sliders, curves, levels, ... what ever Aperture offers, is just not enough, but the adjustments then need to be brushed on the red bits only. For example lowering saturation to a point where a red jacket starts to look ok, already turns skintones to crap.

There is no real solution as far as I know. I have tried to build presets with no luck. In some cases I have been forced to turn photos into BW, because fixing the red channels has been too difficult. Now I'm starting to think that it is not really possible to take photos of red objects. Just like I don't go out in bright sunlight to take photos, I maybe shouldn't take photos of red things.


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## jrista (May 27, 2015)

bluemoon said:


> jrista said:
> 
> 
> > bluemoon said:
> ...



I'm not sure why you would try to remember a color without remembering the way you would describe it. Our memory is about associations and contexts...to try and remember something out of context or the associations we make with it is an exercise in futility. I was never talking about spectrum or the eyes sensitivity to any particular part of the spectrum or how we mathematically define colors or how we name them or anything like that.

I was referring to the way people remember color. We remember color the way we expect color, and in that respect, remember colors best when they seem appropriate. In that context, it is easy to look at a photo with red flowers in Lightroom, and feel the colors are wrong. 

This isn't some colorimetric thing, it's a psychological, perceptual thing. The CIE Lab space maps the range of colors visible to the human eye, and most computer color gamuts do not reach as far into the reds, violets, or blues (particularly, if the later versions of CIE's Lab space that utilized a 10 degree foveal spot in testing are any indication) as our vision allows us to see.

I have a ton of tulips planted in my yard, spanning the color range. Whenever I take a photograph of them, I can never get the reds or purples as rich and deep...yet still as detailed...as the flowers are in real life. The information burns out and loses microcontrast if I try to push the color saturation for any given channel near the reds or violets or magentas that far, and the saturated colors are still rarely right. Not only do I know the colors are wrong, I can step outside and verify they are wrong.

It's not the spectrum, nor is it the specific "color" as mathematically modeled that we remember. We remember color as we have come to expect it. Natural colors are easiest to remember, and bright, vibrant, saturated colors that we come across in nature are usually the first we sense are wrong in our photographs. At least, I rarely ever feel that I've captured the non-green, non-earth colors well in my photos.


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## mb66energy (May 27, 2015)

bholliman said:


> I sometimes struggle to get reds to look "right" out of my 6D and 5D MkIII. Attached is a recent picture of some bright red tulips taken with my 6D and 135L lens. I tried different profiles in Lightroom and played with red and green hue, saturation and luminescence, but the red color doesn't match the color I remember seeing. I ended up using the neutral profile, which comes closest to my recollection. I have not tried setting up my own profiles yet.
> 
> Anybody else experiencing these problems? Any suggestions on how to correct?
> 
> Thanks



I added some info to a thread several months before because I "suffered" from the limited capability in reds:
http://www.canonrumors.com/forum/index.php?topic=22204.msg424412#msg424412

@jrista: Perhaps green is easier to reproduce because red and blue channels help to adjust the green. But red and blue have to live on it's own - there is no IR or UV channel supporting color reproduction from the "left" or the "right" side of the red/blue pixels spectrum.

Funny: After getting two 5D classic cameras the problem is more or less solved. They give very good color reproduction for reds (Poppies, red tulips), much better than 40D, 600D or EOS M.

Some remarks to things I read here:

 Someone stated that the CRI in a forest is 1.0. Never. CRI = 1.0 describes an ideal black body spectrum provided (mostly) by the sun, incandescent bulbs, candles.
Introducing any filtering reduces parts of the spectrum or enhances a more or less narrow band of the spectrum. A forest shows more green than red and blue in the spectrum. Look at the forest scene. Changes are subtle but this tiny correction gives a much more shades of grey green.


* The "right color" is maybe very sensitive to the perception of different individuals but the color differences within one object will be recogniced by most of the individuals similarily (hopefully it is still english language .
The two poppy flower images show the differences in the rendering of the texture of the leaves - just here it's subtle but changing the K-value from 5200 -> 4400 gives more structure in the reds and helps to discriminate them.
This image is made with a 5D classic which gives me good results without postprocessing - mentioned above.
]


Comparison between no color corrections


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## danski0224 (May 27, 2015)

In line with the 5D comment above-

There is something different about the color rendering from older Canon cameras. 

The 1D, 1Ds-1DsIII and 5D (Mk I) all have positive comments specific to color rendering. 

Coincidentally, none of those cameras have good high ISO performance. 

I have read posts from others in the past about the sensor CFA actually altering colors. One post over on FM illustrated how some colors reproduced in one camera but not another. 

Maybe the push to have cameras with an ISO range of 100-26000 has taken color away. 

I can say with certainty that files from a 1DsIII are distinctly different from a 5D3.

Maybe the 5Ds/r are attempts to correct the vanishing colors. If Canon makes a worthy 1DsIV, I'm in.


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## mb66energy (May 27, 2015)

danski0224 said:


> In line with the 5D comment above-
> 
> There is something different about the color rendering from older Canon cameras.
> 
> ...



Good to hear another ones perception of the color rendering of the 5D classic (and it's "siblings").

Perhaps it's a matter of narrower filter spectra cutting out more light but giving a stronger definition for red, green and blue channels. The trade of is having less light on the photo sensors which leads to a lower ISO sensitivity ...

Oh this world with never ending compromises ... but I like the 5D classic very well. It is one of the better compromises at least for my photography.


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## danski0224 (May 27, 2015)

While I do not own a 5D mk1, the differences in colors between the camera bodies that I have tried are noticeable. 

I actually like the 1D (4.2mp) output, but there is no room for cropping. Maybe part of it is the CCD sensor. I should take it out again soon.

The other issue with that body is no AFMA, and no Canon service. No way to tune the lens to the camera.


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## bluemoon (May 27, 2015)

jrista said:


> bluemoon said:
> 
> 
> > jrista said:
> ...



OK, that's a valid point, but it does not invalidate my point that we have issues with remembering the color and that such a phenomenon could be the cause for the perceived problem under some circumstances. 

pierre


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## martti (Jun 3, 2015)

*Re: Reds, the Polaroid guy Land was a genius, nothing less!*

Now, please spend a while to appreciate the genius of Dr. Land.
Nobody in the realm of psychology had ever observed these phenomena.
They did not exist.
But his guy run the necessary scientific tests to show that this is one of the ways our sensory system creates a mapping or an image pattern that our brain can take advantage of in plannning approacing-retreating, fear or recognition..
No, he did not study the emotional connections, it was to fall on other cross-cultural scientists such as Christopher Koch..

Seriously creative guys! Hats off.


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