Inspired by Tony Leece's images with an unguided Dob, on impulse I decided to give my ETX-105 a rest and instead put my ZWO ASI120MC-S and 2.25 Barlow on my unguided 10 inch Guan Sheng Dob.
Since the mount and finder were not at all optimized for the required finesse, to give myself my best chance I went for bright Mars rather than dimmer Saturn (Jupiter was already too low). I hoped to locate the planet and then get the planet drift into view of the camera and so collect a small number of some reasonably sharp images but on this attempt only succeeded in collecting some clumsy flyby passes amid many minutes of blackness. Nevertheless with the camera set to 60 fps I did capture some images and after stacking think I still obtained a recognizable Mars and with possibly less of the Gibbs effect I always see in my little Mak.
Last edited by foc; 12-09-2018 at 11:41 PM.
Reason: Wrong month entered
I think Registax just reveals the effect. There are other causes that also look like it but I susepct Gibbs is th emajor issue in the Mak.
The Dob image shows some sign of it but it does not seem to emerge as quickly in Registax with it.
I have a few 105mm Mak images posted here of Mars (as well as Venus, Jupiter and Neptune) but here is one of Mars I have to hand from September for comparison.
I had a go at getting Saturn with my manual Dob but I just could not nail the sucker though I had it for a second on the edge ..for some reason it was too hard to get in the FOV and so just ended up with more Mars images like the attached . I may have a go on Friday when I can set up during the day , but use the manual frac on the AYO mount instead which should allow the reducer with the 2.25 barlow and might be smoother to hand guide. This way all of my scopes will have had a go this year!
How did you cope with Gibbs effect?
I tried to sort it out with adjusting wavelets and de-ringing in Registax6, but it is always there (this was also shot with 10" Newt on dob mount, unguided and without tracking (because of problem with electronics).
Yes the Gibbs effect is annoying. Apart from mentioning it a few times in my posts in the hope someone else has an easy solution, I haven't done anything with the Gibbs effect (if that is all it is..I wonder if crude tracking also contributes). With the Mak..I can sometimes see it even during capture. With the Dob images..yes it is much less prominent as can also be seen with the attached additional image but although I hoped it would be only minor in a much larger scope it my be just that the focus was not good enough to show it well. Your image Bojan is I think either better guided or better foccused.
Since I have not getting much benefit from the Dobs resolving power I have been busy this week with my Mak this week getting Olympic Mons etc..as per attached. I shall be able to set my my frac in daylight today and with 140mm frac going tonight I might get smoother manual mount images that just might give the Mak with its Alt Az automatic tracking more competition
Well thanks for that Ross. I love the detail you have there by the way mate, lovely images. I'd still have a go at Saturn though mate 
