Use image>adjust>desaturate.
Then play with contrast/brightness to optimize the image.
Most publications will want the file saved in tiff format (but check).
supplement:
till now i just convert it with grayscale, but then the picture is to gray, there is no contrast. Therefore i used the levels.
But some-one told me once that the best way is to convert to b/w is to use the channels…
You can use the Channel Mixer. Layer -> New Adjustment Layer -> Channel Mixer. Tick Monochrome, and mix with the RGB sliders. When contrast in the original is good, then make the total count for the the sliders 100.
This Channel Mixer enables us to filter colours like using colour filters screwed on the camera.
Rob
Take a look at the three channels. Generally, one of them will be a very good grayscale image. Delete the other two.
Bob
Don,
That’s okay but you’ll still have an RGB image. It will need to be converted to grayscale after the adjustments.
Bob
Sorry Don i cannot agree with that. The first thing you learn in a prof. Photoshop seminar is never, ever use the brightness/contrast tool. U’d better use the level-tool. Or the curves.
I was still suprised that the brightness/contrast tool was still in PS CS…
I just experimented with Robert’s methode. After that you can use the ‘levels’ in the color you didn’t delete. To optimize the image.
Rob, your methode works also, but it’s tricky. Just move the slides just a little bit, not to far, otherwise the contrast is to much overdone.
And if that isn’t enough try seeing in Black and White at Russell Brown’s site.
www.russellbrown.com
The Hue/Saturation technique is well worth a look.
Another quick method which can really enhance the tonal range of a BW image and takes the pain of deciding what channels to combine is to convert to LAB, click on the L channel and convert to grayscale from there.
FWIW I actually prefer Robert’s method the best and it is dead easy. Open the Channels palette and see which channel offers the clearest B&W picture – one channel will usually stand out. Highlight it and from the flyout button click Duplicate Channel>New and a new document with result. Then click Image>Mode>Grayscale to change the document from a single Alpha Channel format to a Greyscale image.
Shadow/Highlight, Levels or Curves then make for some great controlled tweaking. Levels is dead easy to use and an S curve usually does the trick in correcting residual contrast issues too.
Compare your result to a simple "Change to Greyscale" effort – which is also an option (a poor one as you’ve experienced) and you’ll see what I mean.
Adam.
"…FWIW I actually prefer Robert’s method the best and it is dead easy…"
The choice should not be influenced by ease. All of the methods are simple enough. Differences in ease of use are trivial. The method giving the best result should dictate the choice.
Selecting the one best channel will not o[ptimize the result. It is better to see what mixing contributions from the three channels in monochrome mode will do. If one channel, say red, looks best, make side-by-side comparisons of 100/0/0, 80/10/10, 60/20/20 etc., percent.
Perhaps the poorest method is Image > Adjustments > Desaturate. That approach sets the gray level at each pixel site based on the average of the highest and lowest channel values at the site, without weighting the channels for their relative stimulation of the eye. The method which converts the mode to grayscale compensates at least a little for the eye’s disparate spectral responses by holding luminosity constant. But I’d go with Channel Mixer. Any further adjustments via levels or curves would be applicable to all approaches.
George
Mitch,
Thnx!!
Great site of your’s with great PS tools and tips!
Cheers,
Eeb
