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#1 vomit

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Posted 26 May 2008 - 01:11 PM

Here are a couple of pics I took of Saturn in April with the LPI and my Meade LX90.  I am curious to know how to make the image "larger", i.e. to have a bigger file to work with.  Seems like anything under 20K is not going to have much data to work with.  Some of the pix I have seen show a wealth of Saurnian detail, Cassini division, moons, etc.  Plus the actual "size" of the .jpg is bigger than what I have.  Talk to me.

Blatz for all of you fine folks.

#2 wsuriano

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Posted 26 May 2008 - 02:09 PM

I usually save my planetray images in either bmp or tif format, not as jpgs.  Both tif and bmp are 24-bit uncompressed.  I seem to have problems reading tif files created in Envisage in other programs so, most of the time, I save as bmp files.  Also, in post-processing, you can always resize and crop the image.  If you're asking about making your original image "larger", use a barlow, to fill more of the chip with the planet in the first instance.

#3 vomit

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Posted 26 May 2008 - 02:45 PM

Thanks.  Will do.

#4 vomit

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Posted 28 May 2008 - 04:07 AM

I took an LPI pic last night of Saturn.....over 100K (using the 2x barlow)...hence the file is too large to attach here.  I think it may be out of focus.  I would like to know if anyone who has experience using Registax or a similar program would like to take a shot at "tweaking" it?  The idea is to see if I took a bad picture or if I just need to practice on using Envisage/Registax.  I did run it through a trial in Registax and I did make it look a little better.

If anybody is up to the challenge just post here, or you can email me direct at tberthaume@yahoo.com.  Please put "Saturn" in the title of the mail just so I don't delete it.  Thanks.

Tim

#5 wsuriano

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Posted 28 May 2008 - 11:03 AM

Next time you shoot Saturn, try stacking the image on the fly in Envisage.  Set the minimum quality level to 80-90% and set the evaluation count to 20 to even out bad seeing.  Save in bmp using normal operation.  Check autocontrast and adjust the exposure time so you get a dark, but noticeable image.  Then, hit start and watch the image build on the screen.  If after 60 or 70 images being stacked, it looks like your image is fuzzy, go back, refocus and hit start again.  Play with your settings until you get something you really like. 

#6 vomit

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Posted 29 May 2008 - 04:34 AM

Thanks. I am going to try and take your advice.  I wish I could actually work with someone who has a lot of experience capturing/processing images.  Alas, I guess I will figure it out by myself.

Thanks again,

Tim

#7 wsuriano

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Posted 29 May 2008 - 08:03 AM

Yeah, I know what you mean.  I've told Mark that he should charge a bunch of us $1,000 for a long weekend where we would stay with him and participate in his imaging and post-processing sessions.  So far, he's not biting.  Maybe he's building the hotel next door?

#8 Tony

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Posted 17 June 2009 - 10:55 AM

"coaches" are priceless in this learning curve! I have used a mask on a bright star to focus the system... Once focused, you can moe to yoru target.... focusing is the weak link in all of this... its so easy to be off and you need to be right on at high magnificaiton... problem is the field of view is so narrow that centering saturn using a 3x barlow can be quite a search.

I agree to having found the dimmest image I can see of saturn during capture is the most successful to process. I also use the sharpen on the fly in planets... seems to help a lot. and I cut the image acceptacne rate way down to take only the best 50% or less.

cheers




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