Help with planetary imaging with Nexstar 6SE

[hobnobber]

After a small amount of success imaging with an ED80 and DLSR (the usual suspects - M31, M42 etc) i thought i'd have a go at planetary imaging - aaargh, I thought this was going to be easier than imaging deep sky!

I'm using a Nexstar 6SE and Phillips SP900NC (with and without x2 Barlow lens) with some software called wxAstroCapture and just cannot get a good enough image of Jupiter to even think is worth bothering to capture.

All I can get (at best) is a fuzzy blob on screen on which i suspect cloud belts but i end up staring at the screen for so long i might be imagining them.

So far, I've tried\checked:

1. Focus - I spent a good 30 minutes last night adjusting the focus by the smallest possible amounts and then viewing on screen and never got anything decent.

2. Seeing - It's not shimmery as I'd expect for seeing to be the cause, it's just a fuzzy blob.

3. Gain, Gamma, Brightness - I've adjusted all of these until i start losing my rag with it. The only time i suspected cloud belts was at 0 gain, 0 gamma and about 15 brightness. Does this sound about right?

4. Visual check - Viewing through the EP shows a very good visual image, both with and without the Barlow.

5. Moving to the moon - i can get a recognisable image but it is still more blurry than i'd expect. I also tried step by step focussing on this with no luck.

Whilst I realise that some frames of the AVI will be bad and others good, i'm not seeing a single good one and stacking just results in a blob. I'm obviously not expecting images like some of the ones I see on this site and elsewhere, but something recognisable as the object i'm imaging would be nice .

Am I expecting too much from the kit i'm using or is the problem more likely to be 'operator error'? Another night moving the focus knob fractions at a time is not appealing to me!

Thanks,

H

[Wildwood]

I haven't used that scope, but it sounds very similar to a problem I had when first using that webcam with my 250. I could not get a clear picture at all and soon realised when experimenting during the day that I simply could not achieve focus. I had a bit of a play with the eyepiece adaptors and found that moving the webcam closer to the seconday solved the problem. Hopes this helps.

I also use Sharpcap, which is free and easy to set up.

[Wildwood]

I also found this infromation useful (I think I found it on here):

All you need to worry about are the "exposure" and "gain" sliders. Find your target (!) with the both the exposure & gain more or less fully to the rhs (ie longest exposure and highest gain) - it will be horribly bright but at least you will probably see the out of focus planet!

As soon as you can see the planet drop the gain to half way (about 30) and then lower the exposure to get an image that is under control (the exposure moves in steps - it is not a smooth "slider"). Then carefully focus the image - spend as much time as you can to get this dead right. You may need to play with the gain to get a good image on the screen.

When you have good focus, set the gain back to 25-30 and set the exposure to the setting that is just a bit too dim ('tis obvious when you se the screen) and then use the gain to GENTLY get the image to a suitable brightness. The sky background should be almost black - if it is blue and has noisy lines across it the gain is too high!

[Wildwood]

[hobnobber]

Wow - thanks for the very prompt advice Wildwood.

Downloading Sharpcap now and looking at various weather websites to see if i can give this a go tonight!

[Demonperformer]

With Jupiter, using a 6SE and neximager (which is basically the same as the phillips) I used to use ~1/100 second exposures. Remember it is always better to under expose (you can bring out faint detail in the processing) than over expose (which burns out the bright detail and you can never get it back).

HTH