Jupiter imaging problems

[njs]

Hi,

looking for some advice on what I could be doing wrong. I don't seem to be able to get images any better (sharper, in focus) than this one. I used a skywatcher 200mm reflector, a 2x barlow, one of those SPC 880 webcams we all got from Morgans though mine has stayed un-modded, vlounge to capture about 17 secs of video and stacked, brightened, played around with contrast, colours, histogram, sharpening filters in registacks. The scope was outside for about an hour before the image was taken to cool down. But I couldn't focus any sharper, I know I should be able to from the fantastic images posted on here, but I'm just a bit bewildered. Any comments welcome.

Thanks.

[jgs001]

Neil, vlounge isn't ideal for this as the sliders have no indication of amounts, and I found it too easy to move the slider the wrong way... Check out sharpcap, wxastrocapture, qcfocus (capture programs) and wcctrl (webcam control softare)

It looks like the focus is out slightly, spend a lot of time getting that as accurately as you can, try and zoom in on the software if possible, it'll help.

What frame rate were you running at ? These cameras are USB1, which means that to use a frame rate higher than about 10 to 15 fps, the camera starts to compress the data, and that will result in losses in the capture. Try and keep the frame rate at 10 or under.

Does your scope have a single speed rack and pinion or does it have a crayford focuser ? I think it's probably the R&P ? If so, try and remove as much slack as possible from it with the adjuster screws and consider the teflon tape mod. It's a cheap way of making the focuser work much better by removing the slop between the draw tube and the focuser barrel.

[lukebl]

You should (and you will) be able to get some fine images with that setup, and modding is irrelevant for planetary imaging.

In my view Vlounge is useless, and I use QCfocus (simple, free download) to capture, and try to get a good length of capture, say 2-3 minutes (no more due to Jupiter's rotation causing blurring) at 10-15 fps. 17 secs won't give you sufficient frames for a good final image. I try to have 1200-1800 frames. Focus first on a bright image, then adjust the exposure settings to get the optimum settings.

[njs]

Thanks guys, sounds like very sensible advice. It is a R&P focuser. The video properties say it was 24fps which doesn't sound right, but I know I set it in vlounge as high as I could. I'll report back after my next session out.

[brianb]

It's possible that you have poor seeing at the moment ... the seeing here has been so wobbly that I haven't even attempted to image Jupiter this last few nights. If you're getting a nice, steady, crisp image in the eyepiece at x150 - x200 and still aren't getting anywhere with web cam images, there's something wrong with your camera or technique - but planetary imaging isn't as easy as it appears by the quality of some of the images posted here and elsewhere.

It goes without saying that your scope needs to be accurately collimated and properly cooled to ambient. But if it isn't you won't get a decent eyepiece view either.

[njs]

Hi Brian, you could be right there but collimation will be my last resort as I don't have a collimator at the moment but I have used a video camera to collimate as suggested in one of Doc's threads and it did improve the image.

I'm looking to acquire another eyepiece which will give a more useful higher mag as I only have a 25mm, a 20mm to 7mm variable and a pretty useless 2mm. I tried to squeeze max mag out of my scope before known enough about it, with a 1000mm focal length scope, I mistakenly thought a 2mm EP would give me a good 500x image... .

[Virgoman]

Hi Neil,

As Luke said earlier, you need a video capture longer than 17secs. I usually try to capture about 2mins at 10fps. Focusing is the difficult part - devil in the detail as it were - along with dodgy seeing, which has been poor here lately. Keep experimenting!

Best regards,

Ralph:)

[njs]

Thanks Ralph, thinking of saving up for a crayford, my R&P has so much play on it I've been thinking of stripping it down and "servicing" it for a while now and I'll give this teflon tape mod a go too.

[njs]

I went out tonight just to experiment with a longer video of 3 mins, framerate down to 10fps and fullscreened it while finetuning (bit of a joke with R&P) the focus and the scope had been outside for 4 hours before using.

And the results were... no better. Seeing was definitely worse as the sky was turning orange as the night progressed. But I think my biggest problem is focussing. I'm going to have another look at collimating because even with an EP I don't see any further detail and also strip this R&P focuser down and do that teflon mod.

[njs]

Well, I bought a cheshire collimator and lined everything up as best I could, damn fiddly. I installed wxastrocapture and have performed the teflon tape mod thanks to a kind donation from a fellow forum member which I must say has improved focusing a great deal. I let the scope and webcam cool for 1-2 hours, no barlow this time, focused as best I could, captured 3 mins at 10fps (about 1500 frames), played around in registacks and this is all I could manage. Seeing wasn't good. Maybe it's my use of registacks, I'll have another go after plowing through the Registacks Tutorial.

[Clayton]

It definitely looks like either focus, collomation, seeing, or optics.

I can see a bit of colour shift. Are you waiting till Jupiter is fairly high in the sky?

[brianb]

Seeing wasn't good.

So you're fighting with both arms strpped behind you back.

Try again when the seeing is reasonable.