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michael.h.f.wilkinson

June 10, 2014: My best H-alpha mosaic yet; 36 panel, showing flare?

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Managed to capture some H-alpha shots of the sun just after lunch. Some lovely detail visible in the big ARs which are predominantly in the western hemisphere. Right near the eastern limb, a pair of small, very bright spots were visible. I gather that two X-class flares went off in that area around that time, so I either caught the aftermath, or the start. I stacked the images with AS!2 (using flats created with Registax and ImageJ), did wavelet processing in Registax, made the mosaic in Autostitch64, sharpened the result with Fitswork4 using deconvolution, and used curves for pseudocolour with Gimp.

post-5655-0-38402500-1402422055_thumb.jp

Full resolution here.

Without pseudocolour:

post-5655-0-50589500-1402422112_thumb.jp

Full resolution here.

Without deconvolution

post-5655-0-00607200-1402422167_thumb.jp

Full resolution here.

Pretty chuffed with this result, especially with the 35mm aperture of the LS35. I used the TV PowerMate 2.5x and DMK21 with Firecapture. Deconvolution really adds extra sharpness.

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Really cool images, Michael :laugh: :laugh:

No solar luncheon for me today, what a day to miss out! My car was in for service/MOT, so I was solar scopeless! Think I will carry on taking the scope to work for lunch. even if I manage to get some clear in the morning. You never know when things are going to kick off!

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Very nice Michael. 36 panes is a true marathon and you can't see any joins.

Robin

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Thanks guys. I snapped 36 panels with huge overlap, and some doubles because I lost track, and want to keep my perfect track record for no missed bits in mosaics. I have used a "mere" 27 before, but with firecapture I could capture runs of 800 frames (13.3 s each) very quickly indeed. Its the processing that takes most time. It would be nice to automate that work flow more. The process I did this time was far better than my previous one, so I am thinking of redoing a couple of older mosaics.

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Wow!! these are tremendous images for such a small scope :) :) :)

Alexandra

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Wow!! these are tremendous images for such a small scope :) :) :)

Alexandra

Thanks, Alexandra! Still no cure for aperture fever, of course :)

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Thats a very good result! Amazing what 35mm of aperture can show!

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I agree with other comments - an amazing set of images.

No visible joins, and more importantly no changes in brightness between frames as the sweet spot moves around the disc.

I really do need to get the hang of that last part :)

Lovely images Michael, really very good indeed!

Ant

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what a superb end result, excellent work as others have said not a join in sight!

I agree with other comments - an amazing set of images.

No visible joins, and more importantly no changes in brightness between frames as the sweet spot moves around the disc.

I really do need to get the hang of that last part :)

Lovely images Michael, really very good indeed!

Ant

36 panel! Wow! Lots of patience there Michael! Great shots! :shocked:

Thanks, all!

I think there are three reasons it works well: First of all the small FOV using the DMK21's small chip combined with the 2.5x powermate means the sweet-spot covers the whole chip. There is very little in the way of gradients. The second reason is the sheer number of panels, which allows for good overlap. The third reason is that Autostitch works very well indeed. My earlier solar and lunar mosaics showed that already. Some solar H-alpha mosaics which caused ICE to bork, work perfectly in Autostitch. Th LS35 also has a larger sweet spot than the PST anyway, and the use of a B1200 filter helps even more (overkill, but I could get one for the price of a B600)

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