Jupiter 16-6-16 first attempt with C6

[Carole]

Well this isn't going to win any prizes, but I thought I'd post it up for advice in the future.

My first attempt with this new scope, and for the first time ever whilst planetary imaging I managed to split the Moons with a Bahtinov mask to get focus, but despite that I still struggle to get a decent image. 



I took quite a few AVIs, but so far this seems to have come out the best of a bad bunch.
All help and advice welcome.

DBK2104 556 frames 30fps,
Resolution=640x480
Frame Rate (fps)=30.00
Colour Space=YUY2
Exposure=-4
Brightness=0
Hue=157
Saturation=103
Gamma=97
Gain=556
Stacked in Autostakkert and wavelets in Registax, post-processing in Photoshop mainly Smart Sharp and colour adjustment.   

I followed the same processing tutorial that I used last month, but ended up with horrible rings during the wavelets procedure so had to change that. 

I suppose I have made some sort of progress - but still a long way to go. Planetary imaging is so much more difficult than DS imaging. 

[Fay]

Im no good at planetary either Carole!

[RobertM]

Good attempt Carole.

It may be me but do I detect the unmistakable signs of a Bhatinov mask being left on ?

Robert

[Fay]

ha ha

[Carole]

It may be me but do I detect the unmistakable signs of a Bhatinov mask being left on ?

Absolutely not, but I know it is very sharpened it was the only way to get any detail out of it at all.

Carole

[RobertM]

It may be me but do I detect the unmistakable signs of a Bhatinov mask being left on ?

Absolutely not, but I know it is very sharpened it was the only way to get any detail out of it at all.

Carole

Hmmm... must be me not drinking enough then

[JohnP]

something not right there....

[Carole]

Yes, I have come to the conclusion, that despite focussing on the Moons, it is still out of focus, and this is a new (2nd hand)  SCT, so I ought to check the collimation, (it could be the problem), but not quite sure how to fit my CCD camera in the back.  I'll start a new thread on that.

Carole

[The Thing]

Hi Carole,

You haven't captured nearly enough frames. I was doing Mars and Saturn last night and was doing a minimum of 2000 frames @30fps for Saturn (no rotation/blur issues really) (60% gain) and 4000frames at 100fps for Mars (30% gain). Then I have to chuck most frames away, only stacking 30% at most.

Last night I had real problems getting focus, even after using a Bahtinov mask on Del Scorpii. I think the seeing sucked, mind you I was imaging at 20 deg altitude over houses... My focal length is 5200mm.

[Carole]

Well I have a series of AVIs I have 3 min, 4 min and 5 minute gaps.  I'll try stacking more than one AVI then.  It still doesn't appear to be in focus to me though.  It was only the last pair (7 minutes apart) where I had actually used the Bahtinov mask, as before that I could not "find" the Moons Ha ha, they are usually in the FOV, but having a larger scope they were much further out than I expected!!

What's the furthest apart the AVIs can be?
Do you mean you take 4000 frames all in one "go" or in several AVIs.  My version of Sharpcap doesn't seem to offer anything more than 30fps, or could it be the camera only allows that?

Carole

[The Thing]

I think you applied the Monet preset in PS!

For Jupiter and processing with the latest Autostakkert the limit is about three minutes from end to end as AS can do a bit of derotation as it works. More will lead to blurring. You can do more and derotate in WinJUPOS, but that is another whole learning experience.

Yes, I mean 4000 frames in one go. Several guys I have come across do 10000 - 12000 frames in one go, but they seem to be able to jack their cameras up to 200+fps with their whatever gear they are using (14" Celestrons quite often). For Jupiter it must fit in to the three minute window, so 30fps x 180s = 5400 frames. The bigger the capture area the slower the FPS available. I generally capture a Region of Interest ROI at 5200mm F/L with 3.75um pixels of 400x400px for Jupiter, 640x480 if I want a moon or two. Mars is only 200x200 so I can get 100fps, Saturn is 220x220 so 80-100fps is possible.

[MarkS]

As others have said, the result is very strange looking.

Definitely you should check the collimation.

Mark

[Carole]

Thanks Duncan, some info there that I didn't know.  Do you use Sharpcap, I hadn't realised you could do a ROI, mind you I wouldn't want it too small as Jupiter can drift a bit during capture when it is highly magnified. 

Right next job, check collimation, I have worked out how to fit the camera to the 1.25" opening which is sufficient for that.

Carole

[The Thing]

The latest SharpCap does ROI but it depends on your camera driver. I use SC with my old QHY5 on my finder as it's fairly cheap in terms of laptop resources. I do use it to capture as sometimes FireCapture plays up and SC works fine, FC provides a lot of advanced features such as autoguiding on the planet ( helps with the drifting!), ADC tuning, debayer preview and raw catpture automatically.

If you get a lot of drifting during a capture you need to refine you polar alignment (or use FC guiding), it's more critical than for deep sky. I can keep the planet on the chip for 5 minutes with no adjustments

BTW You should collimate with the image train you will use to capture the planets i.e. barlows, filter wheels etc in place and at approx the altitude and azimuth you expect you planet to be at i.e. 60deg for Jupiter, 20 deg for Mars and Saturn, to take account of mirror flop and droop of the imaging train. At the high focal ratios tiny tiny things matter.

Have fun!

[Carole]

Thanks for the info Duncan, I am not sure whether my planetary camera sees stars, so far I haven't seen any, which was why I was going to collimate with the CCD camera.

I don't want to mess around with my polar alignment Duncan, I got it as accurate as I could with Alignmaster, and haven't touched it since.  I only get slight drift, but it could wander out of the range of a ROI.  Alternatively I could set up my guide scope to guide when doing planetary imaging, but have not sorted that out with this new scope yet. 

I also don't recall seeing any histogram on Sharpcap but I'll take another look.

Carole