AP with small refractors

[n5ama]

Hi, I'm new here and have been reading (and observing the great pics). It seems most people either use a guided camera or a catadioptric scope for their images. I have a AP 130mm f8. I am primarily interested in the moon and planets. I also have two mounts (a Losmandy on a tripod and a AP 1200 - a little less portable) so should be ok for a sturdy foundation. 

I have a Nikon D7100 digital camera but also have been looking at the ZWO ASI120MC.

Question 1: What do I need to make this set up work, assuming it can be done?

Question 2: What kind of results can I expect with some work?

Any help will be greatly appreciated, and thanks in advance.

Tom

[ronin]

Well you seem to have or looking at everything more os less that you will need. AP 130 sounds very nice.

Taking moon+plantes to be different from DSO's:

Moon and Planets are usually done via a webcam (ASI120 MC in your case or just get a reasonable webcam).

The scope should be good but as the moon adn planets are bright you could need a barlow, to get them bigger. You may be looking at a 5x barlow.

You "simply" have scope and barlow then project the image direct onto the webcam and take a movie, .avi, file.

This .avi file is then downloaded into a processing package such as Registax.

You tell Registax to select (say) the best 10% of the frames and Registax stacks them and coughs out the result.

OK a little bit more then that but the rest take a bit of learning and/or tweeking.

Startring with a webcam is easy and means you can forget the ZW ASI120 for a while.

DSO's are more involved.

These will be basically scope to DSLR or the ZW ASI120, no barlow.

You may need a flattener to improve the image but again you can try without one at the start.

Images will be long exposure, depending on the accuracy of setup and tracking I am guessing 60 to 300 seconds.

You will take say 10 seperate exposures each of say 120 seconds.

These are then stacked in something like DSS, Deep Sky Stacker. and processed in something like photoshop if required.

For a DSLR to get the exposures you need something called a remote timer - Amazon sell them for about £25 = $40.

Get one for the DSLR and set it for 120 second exposures at 400 second intervals a d 10 of them.

The rest time is to allow the chip to cool.

Detail: The camera may have the optionfor "noise reduction". Simply the camera takes an exposure of 120 seconds, then another of 120 seconds with the shutter closed, in effect a "dark" it then subtracts the "dark" from the exposure and hopefully removes hot pixels. Catch is you exposure is now 240 seconds and the chip need to cool for longer. So you have an exposure of 240 seconds so set the time between exposures to something like 500 seconds on the remote timer.

The ZW ASI120 will be similar.

You will need a T piece to attach DSLR to scope.

DSLR ISO will be something like 3200, everything will be set to manual

From a first go I suggest a decent barlow and the webcam (webcams are cheap)

Webcam: Remove the lens that is in the webcam, this HAS to come out to put the scope image on the chip. There may be a filter that as well I would suggest this stays in if possible.

If you try Jupiter on a webcam then owing to the rotational rate of Jupiter you may be limited to a 60-90 second movie file.

[Grotemobile]

Thanks for all that.I think that has helped

a lot of people including me.I always wondered

about DSO imaging.A lot more involved than

planetry imaging.Well done ronin

Steve

[happy-kat]

Or turn off in camera noise reduction and take your own dark frames and the free software DSS will use them.

Tracking is not enough alone for DSO as tracking depending on the mount might not take into account the earth's rotation.

[n5ama]

Ronin, thanks for taking the time to help me with this. I know I have a lot to learn, especially on the processing software, but it sure helps knowing the best way to go about it with the hardware I have. We are in a season of lots of seasonal changes, ie many cloudy nights as fronts move through the Gulf of Mexico coastal area, but that gives me the chance set up the hardware and be ready when the skies clear.

Thanks again, I really appreciate your help.

tom