Newie alert: Two questions

[stuming]

Hi all,

New to this lark. Got a telescope at Xmas and having great fun with it when I can get outside. I'm trying to avoid buying gadgets etc. for it but I do have a couple of questions regarding accessories.

1. While I don't want to go down the "laptop + DSLR + guiding + Photoshop + 200 frames at 30 sec each" route, I would like to take some photos. I already have a Canon 20D plus the gear means to attach it to the scope. Basically, is the auto-tracking on my AtlAz goto mount going to be of any use to me if I want to try to capture DSOs? I'm not going to be buying a Eq mount that costs the same as the scope so I'm just wondering if it's worth trying it out or not to bother wasting the time.

2. Motorised focus. One of the big troubles I find currently is focusing, waiting for the scope to settle down, re-focusing, not being sure if it's right (Mars, I'm looking at you here) not wanting to touch the scope again just in case it is right, but the seeing is not good at the mo. I imagine a motorised focus would cut out a lot of the scope wobble etc. Can anyone who's got one comment? Are they worth the upgrade or should be looking at a decent set of filters / another EP / a thicker wooly hat instead?

Cheers

Stuart

[Merlin66]

Which telescope do you have?

If it's Alt-Az mounted you're limited to 30-45 sec exposures before you get objectional field rotation.

Depending on the make and design of your scope you can get an electronic focus motor.

The SW unit is pretty versatile.

Ken

[stuming]

Which telescope do you have?

Sorry, forgot to mention that it's a SW 130P. They do their own motor focus gear do they?

[brantuk]

For DSO's you would need a very accurate, equatorially aligned, tracking mount with guiding - the further away the object the more accuracy required all round. Even then you have to take multiple long exposures and stack and process them afterwards. If you think about it you're exposing the chip for long periods during which the object is moving and you are trying to gather and magnify the light all at the same time.

However you can obtain reasonable shots of solar system objects using shorter exposures. You'll still end up with many frames that will still need processing for better piccys. You might benefit from the use of filters.

Alt/Az is not really recommended for astro photography unless you're happy to accept limited quality piccys - otherwise equatorial mounts are the way to go.

With your existing kit I'd say go for shortish exposures and aim for closer objects. You can also mount the camera on the scope and just shoot the sky as it tracks around without attaching to the focuser. To reduce the wobble check everything is put together firmly with no play anywhere but not overtight. You can allways anchor the tripod with weights - sometimes helps.

Of course - the darker the site the better - and choose well placed objects.

[Space Bat]

Unless seeing is perfect - then Mars is tricky when focusing as it will shift in and out of focus slightly and you could be there all night - best thing is to get as good as you can and - then run the capture - then grab as many frames using the AVI and set your stacking parameters to reject the poorer images - you should find that you will get enough good focus images to play with

Chris

[russ]

For planetary imaging the Autofocus is a real boon. I have added it to all of my Skywatcher/Celestron newts/refractors i have imaged with.

Officially the Autofocus doesn't fit your scope but there's a couple threads running on the forum and it turns out that unofficially it does fit the Celestron SLT 130 perfectly, which means it should fit the Skywatcher 130 AZ Goto. If you are struggling with a shakey scope the Autofocus will be the best £50 you have spent.

I'll find links to those other threads for you. Someone else is going to give the Skywatcher 130 a try with the Autofocus, you may want to wait and see how that pans out first.

Russ

[stuming]

For planetary imaging the Autofocus is a real boon. I have added it to all of my Skywatcher/Celestron newts/refractors i have imaged with.

Officially the Autofocus doesn't fit your scope but there's a couple threads running on the forum and it turns out that unofficially it does fit the Celestron SLT 130 perfectly, which means it should fit the Skywatcher 130 AZ Goto. If you are struggling with a shakey scope the Autofocus will be the best £50 you have spent.

I'll find links to those other threads for you. Someone else is going to give the Skywatcher 130 a try with the Autofocus, you may want to wait and see how that pans out first.

Russ

Cool. I'll keep an eye out for that

[russ]

Here you go, have a read through this thread, take a look at the link for the Celestron 130 with Autofocus and see how Waybig gets on with the Autofocus.

http://stargazerslounge.com/equipment-help/97115-fine-tune-auto-focuser-celestron-nexstar-114-a.html#post1380108

Russ