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michaellxv
09-09-2013, 9:38pm
I got some shots in my back yard today and i'm a bit puzzled at the colours that are showing up. In the attached photo look at the flowers not the bird. When I look out my window they are a deep red yet no matter how I process the photo they are very much pink. At first I thought it was my screen but a quick google for bottlebrush images shows plenty of images with the nice deep red that it should be.

Any clues as to what is going on here?

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Dazz1
09-09-2013, 9:46pm
Was the camera white balance set to the right type of light, or auto. Did you adjust the white balance when you processed it?

arthurking83
09-09-2013, 10:02pm
It may have a lot to do with the elevated ISO setting.

Higher ISO induces noise, which affects colour accuracy.

Also, exposure plays a very important role in reproducing accurate colours.
Too bright and they appear too bright compared to how you saw them, too dark and they obviously look much darker than in real life.

There's an exposure 'window of opportunity' to capture the colours accurately which can be as much as 2 or 3Ev, depending on the lighting conditions.

Then there's the colour mode(or space), whitebalance .. and so on and so forth.

Did you shoot raw, or did you shoot in jpg mode. What software are you using to process, or tweak the images.

it all has an impact on how the image is rendered.

My feeling is that the issue you are seeing has many variables at play here. Exposure too bright(for the red channel), WB setting not accurate(true to life), and colour killing ISO setting.

If you shot in raw mode, two things you can try to help are:

lower exposure with some negative exposure compensation in PP... start with -1Ev, and tweak it as you see fit from there.

WB setting looks wrong. The (obvious) telltale are the branches in the trees. They don't have an accurate looking colour to them .. but the part of the problem is that they actually look a bit too red.
With the colour noise associated with high ISO settings, it's going to be hard to tell exactly how a WB change will affect the overall colour balance.
If you shot in raw mode, then you have the option to play with WB settings, and I'd say using the preset WB settings available in your raw converter may be the best option, rather than trying to find a white point using a dropper tool.
That is, if you shot in cloudy conditions, try the 'Cloudy' setting, and tweak it a bit to suit your taste.
Of course in doing it this way, there is the negative side effect that if your monitor is not calibrated, and you're setting colours by eye, then you may be editing the image in an incorrect manner.\

Just some points to think about.

michaellxv
09-09-2013, 10:28pm
Camera was set to auto white balance and I was shooting in RAW. I tried different WB settings in PP but that was just making it more pink.

I am thinking it may just be a trick of the light. The shot in question was taken from abut 5m away, looking at other shots today where I was about 10m away it looks closer to the red I was expecting. Sitting at my desk looking through a (dirty) window I would be at least 20m away.

I will go have a close look tomorrow in the daylight.

- - - Updated - - -

I was shooting in Av mode with the camera was set to auto ISO. It was overcast and late in the day so the light was not good.

On the histogram the red channel was blown out, I took your sugestion and had to go to -1.57ev to bring the red back and the colours are looking a lot better to me. It made the image quite dark but I was able to add some fill light and its starting to look ok now.

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ricktas
10-09-2013, 6:23am
I agree that the image is being over-exposed in the red channel. There is no detail in the flower in the first photo, just colour. You talk about looking through a dirty window, were these also shot through a window glass as well? When you look at the top of the parrot's head in the original presented here, there is over-exposure there are well. AK also mentions colour accuracy and very high ISO's as being part of the problem. I think there are multiple issues with the cause for this, and you need to drop the ISO by at least 1/2. Get your camera off auto-ISO, if you need a faster shutter speed to freeze movement then use a larger aperture (small f-stop number). Work within ISO, Aperture and Shutter Speed to control your camera to get the results you want/need. But get off Auto-mode and start learning.

SteveInNZ
12-09-2013, 11:41am
The metering facility of a digital camera is biased towards the blue/green colors and is comparatively insensitive to red. That matches the world as we see it. However, the imaging sensor is just as sensitive to red as the other colors, so when it tries to meter a flower that has lots of red and very little green, it gets a bit confused and ends up overexposing the red channel.
The way to avoid it is to use an area form of metering rather than spot (on the flower) and to watch the RGB histogram. Just knowing that it can happen is half the battle.

Steve.

michaellxv
12-09-2013, 12:21pm
I had another look at the flower yesterday and from a distance it still looks red to me, but up close it does look like a very dark pink. I wanted to cut one off to bring inside but its in the neighbours yard and I couldn't reach it.

Thanks for all the usefull information, its all part of the learning process.

arthurking83
12-09-2013, 1:29pm
...... Just knowing that it can happen is half the battle.

Steve.

:th3:

I think even with the WB edit, the WB setting in the edited version is still too blue.
If the overall colour cast in the image is more blue(that it may otherwise should be), then adding blue into the red channel of course gives you a magenta colour(which is another way to describe pink!).

Like Steve said, knowing this is half the battle.

I did a quick edit of the edited image:

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edit was very quick and easy. Using LR4, I set the whitebalance using the dropper tool, and hovered around a white area trying to find a good balance of colour.
I think from memory, I chose one of the bright highlight spots just under the parrot.
Hovered this way and that way and watched for changes in colour until it looked OK, and also watched the small target dialogue box as the RGB pixel values equalized as best as I could get them too.
Becasue the image I used was a jpg, you can't really do a proper WB adjustment on a jpg as you can with a raw image, so I can't give you a colour temperature value.
The WB tool in LR4 only gives you a temperature slider as a guide .. not a specific K value as it does for raw images.

I think the red looks closer to what you may be looking for, but is not ideal. it won't be ideal as (already said) the noise in the image is also affecting the reproduction of colour.

In the first image posted the colours are way oversaturated, so the image would have been too hard to work with.
The second image posted looked more natural, and had a good starting base to edit.
You have the raw file, so you can do a lot more processing to get the image to it's ultimate end point.

FWIW: this is a colourwheel.
My reference back, about the higher than expected blue channel in your WB edit, sort of shows what I mean about the red channel being affected by blue colour casting.
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If you note that between the red and blue area of the colourwheel, there is the magenta channel. Magenta is obviously a process of mixing red with blue.

Basic and fundamental colour/imagery info. The camera captures each area of detail as a series of red, blue and green pixels.(RGB)
For display purposes, you also have display colours called Cyan, Magenta and Yellow(they make up the CMY in CMYK .. where K is black). CMYK is used for printing purposes.
The basics are that as you blend one colour with another, they create other colours, and tones of colours.
There are colours that you can't really mix. Well you probably can, but they tend to cancel each other out. Looking at the colourwheel it's obvious as to where these colours are .. on the opposite side of the wheel.
So that you can't mix Yellow and Blue, and you can't mix Magenta and Green, and finally Red and Cyan aren't mixable.

These are the colours you affect either directly or indirectly when making WB changes.
Note how one option for editing WB is the tint(hopefully your PP software has a tint slider.
Also note how the two colours you affect with the tint slider are Magenta and Green. As noted before, they are opposites in terms of processing into the image. As you add green, you remove red.
Same thing happens with temperature(or warmth).
As you warm up an image(increase K), you add Yellow and lower the Blue Channel .. and so on.

Note that even tho I used the dropper tool, it's the same effect as just using the sliders, so basically all I've done is to increase the warmth of the image(increase yellow, decrease blue).
In doing that the image does have an overall yellowy cast to it, which is referred too as warmth.
But(for me) it looks a bit more accurate in terms of overall rendering of the scene, both in terms of red, but also in small usually not noticed details such as the branches of the Callistamon.
In my edit they have a more natural brown rendering, whereas in your WB edited image, they are close to brown, but still too much blue in the mix.(ie. a bit too grey).

This is what WhiteBalance editing is about. Finding a good balance of colours.
If you're feeling a bit adventurous, you can play around with the WB settings to see how it affects the image.
Not knowing what software you use, the obvious explanation for you is to use the temperature and tint settings to see what happens. If you set the image with a preset WB of say Incandescent, watch the colour cast of the image turn manic! :D

Hope any of this make sense to you.
And once you understand it, every image becomes so much easier to edit henceforth ....

Mark L
12-09-2013, 8:29pm
I'll come back and read all this thread tomorrow, however, consider changing WB to daylight in camera for all you photos. I know, you can change it later by using RAW, but different programs do this differently. I've found setting daylight to start with, gives the best rendition of what you're seeing.
Just a thought.