An Idiots Guide to Stacking, Software and Equipment

[star_lord]

HI Guys,

I was wondering if someone could help me getting started with imaging and stacking.

I currently have a Skywatcher Refractor 102mm with an Xbox live webcam modded to fit the scope. Can anyone recommend some good software that will help me take some good images...

I sort of know what stacking is but am confused by dark, flat frames etc.

Also, long exposure times. Is this possible with a webcam and laptop, and please forgive me for the stupid question, but, when I image the moon, it moves at a surprising rate when at x50 magnification. How would this work with a long exposure shot?

Thanks in advance all,

Dan

[jgs001]

Dan, I'm not sure on the software for capturing with an xbox live cam, but you could try sharpcap (http://www.sharpcap.co.uk/). 

For stacking use registax, although I use avistack2 primarily.

You really don't need long exposures for the moon, it's bright, you want to run at a high frame rate, and thus need very short exposures. 

[Marky1973]

Hi Dan

I'm new to this adventure as well, but the first thing you are going to need is a tracking mount - preferably an equatorial - that will allow you to counteract the rotation of the earth against the night sky. Without it you will likely be limited to 10-30 second shots from a camera on a fixed tripod.

Once you have tracking sorted you will need some sort of camera. The webcam will be fine for planetary work - where you use capture software to take a film of your target and then use that to identify the individual frames for stacking - I believe REGISTAX is good for that (the stacking part) but I have not ventured into that branch of astrophotography yet.

You can get started with a tracking mount and a DSLR (which is what I am doing) and then start taking longer exposures that you then stack in a programme like Deep Space Stacker (DSS). You can then take the stacked image and process in another tool such as Photoshop or GIMP.

The best advice I got when starting out was to get hold of Steve Richards "Making Every Photon Count" book from First Light Optics and that will make everything clear! Especially the confusion around LIGHTS/DARKS/BIAS and FLAT images!

Good luck.....it sucks you in and then never lets go of your wallet!

[Marky1973]

Ah, John, I was typing and couldn't remember the name of the software I had downloaded to try - SHARPCAP it is!

[star_lord]

Awesome, Cheers guys.

I have an Equatorial Goto mount but havnt had the chance to properly calibrate it yet. When I do I assume that will suffice for tracking?

D

[jgs001]

For the moon and planets, you can get away with the AZ mount... if you don't spend too long... A full moon mosaic will suffer from field rotation effects between the first and last frames, but that's probably something for a later time anyway ...

The EQ mount will deal with the field rotation, so will suffice nicely. (in fact, you can 'polar align' with a compass, and using the altitude markings on the mount itself for the moon, I've done this many a time in the summer months.

This may help some

http://stargazerslounge.com/topic/66552-making-a-lunar-mosaic/

The principles are the same for doing just one pane, you just don't need to join the edges up.

[stepping beyond]

Let me first start by saying : all comments are spot on but, no one has mentioned always focusing when on an imaging run. Focus, focus , focus is one of the most important issues in imaging Astronomical objects due to fluctuations in "seeing". There are several grabber software out there but, finding the one best for you and your camera is a trial and error thing. Not all applications are the same and the functionality is another thing to consider, I use many applications to achieve an adequate image because I work with freeware and the key word is" FREE". Here's a list of what I use: Gimp, Dss ,Reg6, Avistack ,Virtual Dub , Photoshop Express, Toupview and save my file format in tft. and Fits{astronomical standard} and use Photopad image editor for converting to jpeg " you'll lose some data when you convert to jpeg for posting." Always save your RAW data  in FITS ! to retain the most data " Toupview /Sharpcap/ as frame/video grabbers. If I can pass along some info to get someone going , this is it. As far as what to put your settings on you'll have to play around with different scenarios, not one person could answer that question for me when I started out. I use Cmos /CCD cameras that save my settings and I also right down in my log every detail  from the conditions outside to the camera settings once I've found that "SWEET SPOT", it'll save time on the next imaging run and gives a good starting point.