Digital colours - gaps in the spectrum

[AlanS]

I suppose that, as with film, it's a remarkable thing if the digital technology can duplicate the complete range of colours accurately to match human perception.

But it is annoying when the photographs are clearly wrong.

My Nikon D100, excellent camera though it is, most of the time, cannot handle rich red-purples.
Bloody Cranesbill, as the name suggests (it not being a judgemental comment on cranesbills), has rich, red-purple flowers, NOT anaemic lilac. Same thing happens with knapweeds. Also, plants with purplish blue flowers come out pure blue.

Recently I have started using an Olympus SP-560UZ, mainly for lichen close-ups, and it can give brilliant results, within the limits of the guy holding the camera. I have not yet tested it on knapweeds and cranesbills, but what I AM finding is that it has a weakness in the pale ochre-yellow or green-yellow area. Lichens with these colours come out grey.
Lecanora sulphurea, as the name suggests, is one such lichen, the greenish-yellow colour being a distinctive feature when it grows in large patches on old walls. I now have a series of excellent photographs of it - except that the characteristic colour is hardly apparent - it is just greyish white. I note that colour photo of the same species in 'Dobson' (the standard field handbook to lichens) has exactly the same problem, though this will have been with an older camera or may have been a digital conversion from film.

To get to the point of this post:

a) are these problems simply still a general feature of digital photography, or do they vary from make to make?

b) assuming there ARE differences between makes/models, are there any websites that have tabulated comparisons?

c) any tips to overcome the problem? [With lichens, light shading can give better colour rendition - full sunlight usually gives horrible pics anyway]

Alan

[StuartDH]

Just a thought, if you don't already, set your camera's white balance with a bit of white card just before you take your photos and this should help start you off with better colour reproduction

[AlanS]

Originally Posted by StuartDH

Just a thought, if you don't already, set your camera's white balance with a bit of white card just before you take your photos and this should help start you off with better colour reproduction

Thanks Stuart, but the point is, other colour reproduction is bang on. It is simply these specific and evidently narrow parts of the spectrum.

Alan

[ceterach]

Alan

I have a Panasonic FZ30 and have grave difficulty with all shades of purple, violet etc. I think this is a common problem (my previous Minolta and Kodak cameras were the same) but it is light dependent. If I want to take pictures of plants that colour I have to do it in the morning in bright conditions otherwise they come out blue.

I have played with the white balance as Stuart suggests and that can help a bit not as far as I can see in any logical way, more by trial and error. Similarly fill-in flash helps a little but I don't always like the finshed result

I have not noticed a constant problem with other colours but sometimes depending on the ambient lighting strange quirks do occur.

As a far as I do not know of a site showing comparisons but there must be one out there somewhere!!

All the best

[StuartDH]

The other problem is that monitors, printers, camera LCD viewfinders etc can all produce very different results unless they're calibrated. I run WAB on two laptops and two flat screens and it looks very different on all of them...with screen print outs looking different again.

I remember seeing something a while ago about shooting in RAW and using the camera's software and graphs to make changes. The camera magazine reviews often have good comparisons of colour reproduction

Stu

[BruceP]

Colours are limited by the colour space and its gammut. Are you using a narrow colour space such as sRGB or something wider such as adobe RGB or ProphotoRGB?

Take a look at:
Understanding ProPhoto RGB

[mh68]

The Panasonic bridge cameras are known for having trouble with Reds. My Fuji S2 Pro dslr (based on the D100) had major problems with yellows,and purples too. My current Canon 20D seems to do strange things with greens.A friend of mine, a long time film user, reckons digital cameras in general dont handle whites as well as film.
All makes/models handle colour differently, especially when shooting jpegs, which suggests its how the in-camera image processing handles specific colours.Sometimes it`s documented on the camera forums, other times it isnt.One thing is for sure, it`s very frustrating at times when an otherwise great shot is spoilt by a particular colour either blowing or being recorded strangely.

Mark H

[John D]

Hi Alan,
I am finding this thread to be of interest as 'colour management' is something I have read quite a bit about. What I would ask is 1) what are you comparing the 'colour matching' with, 2) how have you established it is the camera that is not providing the 'true' colours 3) have you colour matched your monitor 4) are you basing the colours on a print-out. ????

Colour management of all devices is probably the most difficult and complex operation in digital photography. As has already been said cameras, monitors and of course printers can all provide different shades of colour and getting an ideal match is not easy. Again as already mentioned whether a camera is set to sRGB or Adobe RGB can make a differenct to how colours look on a monitor which is biased towards sRGB.
There are several very good web pages that details 'Colour Management' all are worth a look. Just GOOGLE - 'Colour Management' hopefully you will get some tips which will assist you.
John D

[glsammy]

Johns point is a good one.

I've recently changed my monitor and the difference in colour rendition has really surprised me. I didn't realize how bad my old monitor was!
I've been lucky, my prints now are as near as I care about a match to the screen display. That certainly wasn't the case before.

[AlanS]

My thanks to everyone who has answered this. Leading me into some interesting reading!

I have, of course, considered monitors - I basically use a good, old-fashioned IIyama take-up-just-about-all-of-the-table monitor which had a good reputation when I first bought it and still appears to be correctly set up (plus various monitors at work). I also have looked at most of the photos on a Sony Vaio laptop - so two different technologies showing the same problems with specific colours - which HAVE to be related back to the images as stored by the cameras.

The thought that this could be related to compression is interesting - I have always saved as high-quality jpegs (sometimes tif if available, which it is not on the new Olympus) but I have ignored the RAW format possibility. I shall look into this and see if it makes any diference. Apparently no Adobe RGB/sRGB choice.

Alan