First attempt at Mars

[rob_r]

Hello! I finally swung my scope on Mars a couple of weeks ago (26th Sept) but given the amount of data I captured, I can't help but feel a bit disappointed with the overall final result. All taken with a SkyMax 127 SCT and a Canon 600D coupled with a 2x barlow. I took about a dozen 90-100 second videos, took the best 10% and sharpened them up in Registax. The final stack was via Siril. There is some surface detail there but it is not well defined at all. I realise that despite Mars being close, it is still a fairly small target compared to the likes of Saturn and Jupiter. The imaging calculator gives a resolution of 0.3" per pixel. 

Is the issue at the acquisition or the processing, or both? Perhaps a readjustment of expectations required too.

There is still some time to retry this target so any further advice would be welcome for a reattempt. Thanks!

[PeterCPC]

How are you focusing? Try focusing on a bright star first with a bahtinov mask before slewing to Mars and not touching the focuser again.

[jambouk]

Great first go. Way better than my first go at Mars.

There are lots of things which may be contributing to this not being crisper. I think the most likely culprits are:

- seeing conditions

- focus

- camera

- maybe planet rotation

You can’t do much about the first other than wait for better swing and ensure you don’t have any local factors making the local seeing bad.

Focus is hard, requires a lot of patience. 

The camera isn’t ideal as the frame rate is relatively slow AND it will compress the data before it is saved. 

If you did 12 x 100 second imaging runs, with gaps in between, you could be trying to stack data taken over a 30 minute period, in which time the planet will have rotated, so this may not help the crispness issue.

It’s an amazing start. You should be very proud.

james

[rob_r]

Thanks for the encouragement, a bahtinov mask is on the shopping list. I tend to focus using the live view on the camera but zoomed in to ensure I get as close as I can. The camera shoots at a 24 FPS rate, which is slow compared to dedicated planetary cameras. I have been trying to get my head around WinJUPOS for de-rotation but I'm finding it a bit of minefield. I can do all the alignment stuff but when it comes to the final processing step I get a bit lost as there is only one image loaded in. I still have the stacked frames so I will keep playing with WinJUPOS. 

[jambouk]

Personally I think your next big jump in improvement will be a different camera, rather than WinJupos. 

Edited October 22, 2020 by jambouk

[ShrewView]

Much better than my first go at Mars.

A bahtinov mask will improve the focus though, which should help things.  It could just be the seeing on that night though, as that makes a big difference.