Copernicus, Sinus Iridum, Clavius, +Uranus +moons

[Tommohawk]

Hi All

Couldn't miss the chance when we had some clear nights here on 17th and 18th, but hadn't done any astro for a while, so the usual panic getting set up. Because there are so few clear nights I try and do a bit of everything - planetary, DSOs, and occasional lunar, to make the most of it. Jack of all trades......

I've only done a few lunar pics before and nothing with the ASI290MM - I went with a  standard red filter, because somewhere I saw that that was better than nowt. Maybe some other filter would have been better?

From habit - ie being more familiar with planetary imaging - I tried to achieve maximum FPS - but really this was pointless because obviously there isn't any rotation so no particular rush to get the frames in. That said with some turbulence I guess it still makes sense to go with short exposures to minimise motion blur during each frame.

Bit of a nightmare focusing - I've made good use of Firecapture's excellent autoalign feature in the past - it holds the image pretty much rock-solid so its possible to focus well manually, even with some scope movement. However, on this occasion, I really struggled - the image seemed to get split into 2 separate images within the window, and auto-align just didnt happen - or at least not normally as it does with planets. Something to do with brightness, or maybe not seeing any edges? Or maybe it would have been better with a smaller ROI, rather than full frame? I couldn't figure it out at all, but somehow got it to work in the end.

I experimented with full frame, reduced ROI, and both with and without Powermate x5. 

Interesting to note the difference between the first series of 3 done on 17th, compared to latter 4 images done following day.

To finish I had a quick go at Uranus - I wasn't expecting any surface detail so I just went native and upped the exposure to capture some moons. Quite a nice result although I'd planned to do a composite with Uranus not so burnt out - started to get frozen though, so packed it in before hypothermia set in.

Wasn't sure how to image Uranus - typically I do AVIs but I needed 1 second exp to get the moons, even with the gain cranked up, so I settled for 100 TIFFs and stacked them in DSS. Seems to work.

I'm fairly happy with the results, but I think I could do better - the clarity doesn't seem quite bang on. Possible down to focusing, maybe in part down to coma - but shouldnt be too much coma on this small sensor.

Very happy to receive any thoughts/criticisms as ever, hope you like the shots. There was an hilarious moment during this session which I'd  hoped to recount - but for the life of me I cant remember what it was - well, it was 7 days ago.

Quattro 250 with ASI290MM + red filter. Firecapture, AS!2, Registax, PS.  Gain unity (351) for lunar, 422 for Uranus + moons.

FC Log file excerpts under images

Frames captured=16643
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=664x492
ROI(Offset)=640x304
FPS (avg.)=108
Shutter=0.270ms
Gain=351 (58%)

Frames captured=14927
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=552x830
ROI(Offset)=696x136
FPS (avg.)=96
Shutter=0.187ms
Gain=351 (58%)

Frames captured=10376
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=968x712
ROI(Offset)=488x192
FPS (avg.)=56
Shutter=0.187ms
Gain=351 (58%)

Frames captured=36341
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=664x492
ROI(Offset)=640x304
FPS (avg.)=100
Shutter=0.148ms
Gain=351 (58%)

 

Frames captured=30823
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=664x492
ROI(Offset)=640x304
FPS (avg.)=95
Shutter=0.198ms
Gain=351 (58%)

Frames captured=10558
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=1936x1096
ROI(Offset)=0x0
FPS (avg.)=20
Shutter=3.781ms
Gain=351 (58%)

Frames captured=11794
File type=AVI
Extended AVI mode=true
Compressed AVI=false
Binning=no
ROI=1936x1096
ROI(Offset)=0x0
FPS (avg.)=23
Shutter=4.981ms
Gain=351 (58%)

Frames captured=101
File type=FIT
Binning=no
ROI=1936x1096
ROI(Offset)=0x0
FPS (avg.)=1
Shutter=1.00s
Gain=422 (70%)

[Tommohawk]

Oh I've just remembered the hilarious comedy moment - except it isn't that funny.

I spent forever with  Autostakkert trying to get a sensible result, but I kept getting a peculiar blocky rotational effect no matter what size APs or any other settings used. After ages I remembered I'd enable an experimental feature which allows for field rotation - so each image is rotated with  respect to the previous one. Once I disabled that, normal service was resumed.

Well.... mildly amusing perhaps.