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Aussie_Dave
03-07-2019, 03:28 PM
Jupiter at 9:48pm last night. Conditions good Mandurah Western Australia. Finally some decent seeing! This is the best I've captured this season from the South West of WA.

Captured in SharpCap, Stacked in AutoStakkert 3, wavelets in RegiStax 6, edited in PaintDotNet.

Image was resized in RS6 to 200% with the Mitchell filter, edited, then reduced to 80% of that size. I find this much better than using Drizzle in AS3!

The second image is only a 2 image gif to try and work out what's noise and what's actual gas cloud detail and gifs are not the best way to show this. Each image was about 197kb in size and the two image gif is now 99kb. I'm rethinking my capture settings to try and get the best faint detail while reducing noise. I've dropped gain on the non cooled 224mc to 180, adjusted exposure to around 60 frames per second and dropped the time of the recordings to 2 minutes instead of 3 minutes.



ZWO ASI224MC
Saxon 8" Maksutov, fl 2500mm, f/12.5
SkyWatcher EQ6 Pro

John Hothersall
06-07-2019, 02:59 AM
Great results Dave, does not look like you have much noise there. I never seem to get the GRS, you got some detail within. I would say 2 mins is better than 3 at much longer FL's but 3 mins is fine at your FL. You need to maximise fps, histo of 70% some even go lower down to 50%.

John.

Saturnine
06-07-2019, 10:51 AM
Pretty nice detail and colours in the cloud bands in the images, always wondered how good ( or not ) the Saxon 8" Mak was / is. Seems they didn't sell well and production was discontinued after only a year or two. Yours seems to have reasonable optics judging by the crispness of the images.

Aussie_Dave
07-07-2019, 12:20 AM
Thanks John. It's been the only good seeing night I've had here this Winter for planetary.

I was capturing 3 minute videos at a much higher frame rate (shorter exposure), gain was at 200 and a lower histo. I found that once I stretched levels for it to look acceptable it was also increasing noise.





Cheers Jeff. There's not many of these Saxon 8" Mak's around. Only a couple that have been sold on the second hand market years ago that I know of and one that may exist over in the eastern states somewhere that I heard about recently. They are ok, heavier than a C8.

I've had some ongoing problems with collimation with this scope but with the help of a member from here, we worked out that they are prone to pinched optics from the cold weather with the front lens cell around the corrector lens, so a dew heater strap is a definite must have for them, also a dew shield and shield the whole scope from it dewing up.





Here's the two stacked images from the two videos, layered and aligned manually with some more colour correction. Not sure if it's any better than the single stacked images. I could do with some very good seeing to see what the scope can really produce.

Wavytone
17-07-2019, 02:25 PM
Good to see you've got it sorted, Dave.

The part about the corrector cell is good to know, as I have known previously all the elements must be just retained in place with no real force applied from the cell or clips, or else the image will be affected. Differential expansion is an obvious problem with cells.