Colour problems

[hallucygenia]

Not for the first time, sponges are being difficult. We have some lovely colour photos of a new Silurian sponge from Australia (the only one of its type from that age and continent). So far so good. Unfortunately we can't publish colour photos (too expensive), so we need to convert them to greyscale. When we do this, all the detail vanishes! The sponges are preserved as orange stains on a greenish rock. We've tried fiddling with contrast and brightness as a greyscale image, and with colour balance as a colour image, but nothing seems to work.

There's an overall view of the sponge at:
photobucket.com/albums/y159/joseph00/?action=view¤t=aussiespongeH1_C0_Z01.jpg
This doesn't show much detail, but gives you an idea of the colours involved.

Any suggestions..?

Thanks,
Lucy & Joe

[Roy]

Hi Joe and Lucy,

What an interesting and colourful image!. Hmm colourful, though, may be the problem in converting it to greyscale. The colours in the sponge are all very close in tone, although they are quite different and fairly clearly defined in Hue.

So when the image is desaturated all of the tones blend together and the detail is lost as you say. Soooo, this is where the magic of the wonderful wizard of photoshop comes in handy...

Ok, so first of all it is best to work with the original colour image (a tiff file if atall possible). Then using the droplet sampler, sample a mid range tone of the yellow in the image, then go to 'Colour range' in the 'Select' menu. Slide the 'Fuzziness' selector to a point where you think it has selected an accurate sample of the colour you are selecting then ok it.

You now have marching ants selecting an area of colour within the image. Now select 'feather' from the 'select' menu and apply a feather value of say 2 pixels. Ok, back to the image. Now, from the
"image - adjustments - brightness and contrast' menu, take the brightness down to a level which clearly separates the tone of the colour from the rest of the image. Then repeat this process for the other tones in the colour of the sponge.

Then when you have done all that - desaturate the image and convert to greyscale - it's as simple as that!

here's one I made earlier:

img.photobucket.com/albums/v331/Leroi/aussiespongeH1_C0_Z01.jpg

Happy photoshopping!

Roy.

[hallucygenia]

Thanks Roy! It's taken a lot of fiddling, and several attempts, but I've managed to come up with something that looks good.

[Roy]

Hi Lucy,

Did you use the 'select colour range' command in photoshop? - and is there any chance you could post a link - I would love to see the finished result!.

a.t.b.,

Roy

PS: Joe's link to the original colour image appears to be broken when I tried it just now.