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A Tale of Two Full Disks

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#1 drksky

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Posted 06 January 2013 - 11:09 PM

The clouds miraculously parted this afternoon and allowed me to get some data and to try out the .5 reducer I picked up from Scope Stuff. It's nice to be able to fit the whole disk, but it's not without its problems.

Below is taken with the SMII 90 and the .5 Scope Stuff reducer:
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And here is a 4-panel mosaic of a full disk taken at native focal length:
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The reduced image has nice surface detail but almost completely loses any prominences. I also find that the scope has a bit of a sweet spot that force me to shove the sun up into one corner to get any semblance of even illumination. Is this something that's overcome with the Lunt pressure-tuned scopes?

This sweet spot also shows up in the mosaic as shading in the disk where the panels were stitched together but the individual images don't quite match up.


Finally, I tried some detail shots with the 2X Cemax barlow, but it's tough to get decent data with a camera that only does 12fps. I'm still pondering getting a Blackfly e2v CMOS camera now that they've been released.
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#2 Andy Devey

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Posted 07 January 2013 - 04:45 AM

Excellent shots there Anthony love the 4-panel mosaic, if you do get a faster camera you should be able to go with two 2xBarlows out to 3.2m focal length when the seeing is stable

Regards

Andy

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#3 raylal

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Posted 07 January 2013 - 06:58 AM

Great shots Tony, you were lucky to get the sun. In your first full disk image did you try the wavelets in Registax and the levels in Photoshop. Sometimes you can bring out the prom details by playing with both.

Ray

#4 mbucky

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Posted 07 January 2013 - 08:13 AM

nice work, tony, fine details. pressure tuners help, but do not completly eliminate the problem.

#5 JeanB

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Posted 07 January 2013 - 12:17 PM

Terrific work, Tony!

Jean

#6 AstroPaolo

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Posted 08 January 2013 - 04:50 AM

nice mosaic and details :)






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