Re: [APML] Comet & M13, other

[Matt BenDaniel <matt@starmatt.com>]

At 09:12 PM 5/19/2002 -0700, Bert Katzung wrote:
>Hi Matt:
>Thanks for the comments. I had missed that stacking artifact---thanks for
>pointing it out.That's what comes of imaging an object on two successive
>nights.  Looks like I'll have to crop that part off the bottom.

You don't necessarily need to crop. The corner could be saved.

>I am still struggling with the MBD technique for anti-vignetting and trying
>to adjust the colors in the blurred layer is a major stumbling block.

AV is difficult. There are only a handful of people who can AV without obvious artifacts over an entire film frame when the vignetting is one stop or greater.

I usually draw the AV mask in pure gray tones and use a grouped curves layer to adjust the color. The curves are not always linear.

Note that AV cannot save the entire frame if the density is too low in the corners. That is one reason why I expose for 90 minutes.

>I fooled with your LMC challenge image for a while and  made very little
>progress. It would be great if you could web-publish the details of the
>final "winning entry" in that challenge.

It's not over. Mike Cook asked for full-rez (120MB!) and I think he will make it available to everyone.
--
Matt BenDaniel
matt@starmatt.com
http://starmatt.com


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