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Re: Holland's Question...



<x-charset iso-8859-1>Nice post Rafe - thanks...

> Gad, I think I've covered it many, many times.
> 
> Please bear in mind that my photos do not rely on, 
> and are not meant to represent "objectively accurate" 
> color.  If you need that, ignore the rest of this 
> post.  For my photos, I strive for an image that is 
> pleasant to look at, and believable.  For landscapes, 
> there's often a good deal of leeway.  Of course, 
> people will not generally want to look at a photo 
> that's obviously off-color.
> 
> On matters of color spaces and profiles, I defer happily 
> to The Man from Maine.  I'm still happiest working with 
> Photoshop 4, un-color-managed, and profile-less.  But 
> I do take my numbers seriously <g>.
> 
> But the gist of it is to "go by the numbers" as 
> much as possible.  I try hard to identify something 
> (even a few pixels) close to pure white, and pure 
> black, in each image.  I use the curves tool to 
> get the black to (5,5,5) and the white to (250,250,250).
> I look really hard for something in the image that ought
> to be neutral (a rock, say) and set that to R=G=B.  
> That's the core of it...  If there are no neutrals 
> in the image, it's tough.  But by the same token -- 
> an image with no neutrals is less likely to be seen 
> as "off-color."  Unless, of course, you've messed 
> up some reference colors and printed the bananas as 
> orange, or the oranges as lemon yellow... <g>.
> 
> The actual values used for "black" and "white" are 
> somewhat negotiable, within reason.  If you plan 
> to do a lot of unsharp masking, you might want to 
> be more conservative, and use 10,10,10 for black,
> and 245,245,245 for white -- because the USM step 
> will push the tonal range back out toward the limits.
> 
> One very useful "trick" is to look at each of the 
> color planes separately in Photoshop, and consider 
> each as an image in its own right.  If any one of 
> the color planes is blown out, muddy, or blocked up,
> re-do the scan.  Of course, it's not always possible 
> to get all three looking beautiful.  Most likely the 
> blue channel will look less appealing than the other 
> two, and red will have the best detail and contrast.
> If it's not possible to re-scan, use the "Calculations" 
> tool (PS4) or the channel mixer (PS 5 and above) to 
> "steal" detail from a good channel and lend it to the 
> channel that's hurting.
> 
> Another thing to remember about the curves tool... 
> the steeper the slope, the better the contrast.  
> Find the "focus" of your image, and work the curves 
> gently to make them more steep in that area.  This 
> takes some experimenting, and there's always a hard 
> tradeoff.  If the curve is made steeper in one region, 
> by definition it must end up less steep in other 
> regions.  Margulis calls this horse-trading, and 
> Haynes/Crumpler show how to use "lock-down" curves 
> to carefully tweak color or contrast in a select 
> region of an image.
> 
> Contrast and sharpness go hand-in-hand.  "Unsharp 
> Masking" is nothing more than a contrast-enhancement 
> where colors change.  Contrast has everything to do 
> with the *perception* of sharpness and detail.  
> 
> Well anyway... most of these tricks come from a dude 
> named Dan Margulis (there, I said it...)  Dan's a bit 
> of a CMYK fanatic, so that part has to be taken with 
> a large grain of salt, if you're working in RGB.  But 
> it is impressive how many of his "tricks" translate 
> to RGB space as well.  Dan is by no means the only 
> expert...  I learned a few good tricks from the book 
> by Haynes/Crumpler called "Photoshop Artistry."
> 
> The beauty of the numerical approach is that I don't 
> rely on monitor calibration, and my images often look 
> better in print than they do on the monitor.  I'd also 
> posit that, with Epson inks and Epson papers, profiles 
> are not needed to get excellent prints.  Where profiles 
> *are* useful is when non-standard inks and papers come 
> into play, with dot-gains (for each color) that vary a 
> good deal from Epson's design values.
> 
> 
> rafe b.

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