Re: [APML] Reflecting on Cygnus

[Chuck Vaughn <aa6g@aa6g.org>]

  Jerry,

> I hate to be the bearer of bad news, but Timo is a well known web  
> quack. He is legendary. He advocates using a linear gamma, and  
> although his site sounds authoritative, I would not believe  
> anything I read there, nor would I use any charts that he produces  
> to decide anything about the display of my monitor.

Oh man, and the chart looked so cool!


> I would be much more inclined to believe something I read here:
>
> http://www.normankoren.com/makingfineprints1A.html
>
> about monitor gamma and calibration.

I used this one to estimate the gammas I set in several profiles for  
the monitor and it seems to work.

> You know what I use?  I use your 18 step grayscale step wedge. It's  
> the greatest thing that was ever invented. And I use Adobe Gamma.  
> And even then I have to cheat a bit because the display always  
> comes out too dark with Adobe Gamma, I can't see the darkest steps  
> on the step wedge.

LOL! Well I'm glad it's useful but it's simplistic.

> There's also some info here by Ian Lyons on calibrating an LCD  
> display in OS 10:
>
> http://www.computer-darkroom.com/colorsync-display/colorsync_3.htm

Yes, that's what I've been using. The gamma setting is poor though.  
It's hard to tell anything looking at that little picture.

> I think the problem you may be running into is the old Mac gamma of  
> 1.8.  It's just not valid or used anymore.
>
> On the LCDs I use, I just don't see that much of a difference.  I'm  
> on a Windows platform though. More hints of evidence that it's a  
> mac gamma thing.
>
> 1.3 definitely does not sound right, it's too close to linear  
> (which is what Timo preaches).
>
> Here's the evidence... the numbers don't add up... you got info  
> from Timo, you see vast differences in the displays between your  
> new LCD and your old CRT. It really sounds like you don't have  
> something set up right.
>
> Ian Lyons says "The majority of displays (CRT and LCD) will have a  
> Native gamma somewhere between 2.0 and  2.2 "

I made profiles at 1.8 and 2.2. I can barely see any difference in  
the first two steps of my step wedge at 1.8 or the first 3 at 2.2. I  
can't use those since the first 10-20 levels appear almost black. A  
setting of 1.4 seems to be just about right looking at the step wedge.

I don't know what to tell you. There's no other adjustments.

> I guess that's why you and Rob think it shows more of the  
> imperfections of an image, another reason not to use em :-).

There's getting to be fewer and fewer CRTs available. I'm wondering  
how long it'll be before there are none.

> Personally, I really hate the way LCDs look, but my kids love them.  
> They have young eyes. I guess that tells you something.

I couldn't go back. The sharpness and contrast make such a difference  
in ease of reading on the display.

Chuck
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