Re: [APML] My first Tricolor Shot

[Chuck Vaughn <aa6g@aa6g.org>]

Volker,

It shows red much more than I would have expected. Spring is a bad time for
short focal length scopes.<g>

Did you run some kind of test to determine that the exposure times are
in the correct ratio?

I almost hate to bring this up because I'll sound like a broken record but
the RGB levels are not adjusted properly. Samples of the background sky in
the upper left on average show Red=1, Green=10 and Blue=25. The blank
sky should show roughly equal levels. The red channel is severely chopped
off, the green moderately chopped off and blue is too light. You are loosing
faint detail in red and green and adding a blue cast across the entire
image.

I'd like to see it re-adjusted based on Levels and not what it looks like
on your monitor.

Chuck <aa6g@aa6g.org>

---------------------------------------------

> Hi all,
> 
> I was very silent the last weeks, but there is a good reason for this.
> 
> After a waiting period of more than two years, I got my 12" f3,3 Astrograph,
> itīs called a "Deltagraph". The focal length is 990mm and the optics give
> you pinpoint stars up to the edges of the 6x7-format.
> 
> The second change in my setup is the developer, I now use D19 too, and I
> love the results, especially concerning to the speed. I develop the Tech
> Panīs for 8 minutes at 20 degrees celsius. The grain is bigger in comparison
> to Dokumol I used the last years, but for 6x7-format and this focal lenght,
> where you usually take shots of huge areas, itīs not a problem.
> 
> The third and most interesting thing is the fact, that I have started taking
> tricolor photos with Tech Pan. Iīm working with this fantastic film for
> years now, so I have enough experience to start with this difficult stuff.
> My first image is M101 because itīs the biggest object at the spring skies.
> You can find informations and a link to the high res image here:
> http://www.spiegelteam.de/NewPictures.htm
> 
> I combined the three Tech Pan shots in Registar. After this, I did a little
> color adjustment and stretched the contrast using curves. Soft unsharp
> masking was done at the end.
> 
> I would love to hear your comments to the final result, especially to the
> differentiation of the colors of the galaxy and the stars.
> 
> Best regards,
> Volker
> 
> Volker Wendel
> www.spiegelteam.de
> volker@spiegelteam.de


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