Yesterday I acquired a new toy. An Orion Sirius EQ-G with GoTo. I purchased this to take my astrophotography to the next level. After testing it tonight, I think it will definitely meet my expectations. At this point I only have the Celestron 102mm achromat refractor. It will now become my primary imaging scope. Perhaps next year I'll get an Apo.
During the day I spent an easy hour tweaking the polar alignment scope. Focus was a cinch and literally took a few seconds. But then I spent the remainder of the time trying to align the polar scope reticle so that when I rotate the RA the target object stays in the middle of the crosshairs. That was a much tougher task then I expected it to be. In the end, the target object moves a little, but not much. That was as good as I could get it. I'm not sure if it's like collimation where it needs to be done again after moving the mount around. I hope not!
The Evening Setup
Tonight I went out, but got started way too late. A family birthday party (Happy Birthday Andrew!) was the priority. I didn't get out with the gear until after 9:30pm. It took me until 11 to get the scope set up, polar aligned, 3 star aligned, and a few goto tests. It's the first time I've done something like this as it's my first real EQ and GoTo mount. Its very strange to get used to after owning a Dob. I'm sure I'll get faster at it as I learn more about the exact steps to take. Also, the hand controller stored my LON/LAT settings so I won't have to look them up next time.
Oops... I need a Finder... Duh
One of the problems I ran into that took way too long to solve when I was going for the 3 star alignment was that there was no finder on my refractor. The refractor has been essentially a finder for my Dob since I got it. I replaced the focuser (where the factory finder mounts on to) so the factory finder doesn't work for it anymore. I made something work with a Rigel dot finder that I had laying around. Whew!
The Excitement Stirs
There are a few key things I'm particularly excited about.
1) Finding the object. Star hopping with a camera an no mechanism to see what the camera sees without taking a shot is very painful and time consuming. With GoTo, I can just tell the scope where to go and the object was in the frame (though not in the direct middle) each time. Awesome. That is going to save tons of time.
2) Centering the object. Once I had the object in the frame with my previous setup, I had to manually move the scope which is a Dob on an EQ platform. There is so much uncontrollable backlash and dampening issues with this setup it would take several minutes (or more) to center the object which would drift over a period of several minutes and I'd have to re-center again. Now, I can just use the hand control to nudge the object ever so slightly exactly where I want it to be. Sweet!
3) Keeping the frames. I've tried many different things to get the wiggle out of my setup as well as try and minimize what causes dampening issues. These two things make me end up throwing out as much as 70% of my frames. On an excellent evening with no breeze and the tracking as dialed in as possible I have still thrown out as much as 30%. Well, that is going to be a thing of the past! Unless something really strange happens or a satellite cuts through the image, it looks like I'll be able to keep 95% or more of my frames. Tonights shot was 23 frames and I used 21 of them - and the only reason I lost 2 was because of the fog getting too thick.
I normally wouldn't have tried to image on a night like tonight, but I was just experimenting.
I'm glad I did too because the next time I go to set up I'll be both prepared and a little experienced so it will go much faster.
First Acquired Image
By the time I was ready to image the fog was starting to roll in pretty thick. I managed to get 11.5 minutes worth of M3 frames before the fog was so bad that I had to tear it all down. I still can only take 30 second subs as I don't have shoestring yet. It's on order! I'm looking forward to getting the shoestring because this mount can clearly take longer then 30 seconds without drift. Woo hoo!
M3 - Globular Cluster
Not too bad considering the intense fog I was shooting through. I'm very surprised I got anything even this good. You can see some coma problems in the stars as well as the typical violet halo from the achromat. I have a V-Block filter for visual observation, perhaps I'll try that next time.
Scope: Celestron 102mm Achromat Refractor @ f/5
Mount: Orion Sirius EQ-G with GoTo
Camera: Canon EOS 350 Digital Rebel XT (unmodified)
Special Settings: None
Exposure: 11 minutes 30 seconds - 21 @ 30 seconds
Processing Software: Acquired in Nebulosity, Stacked in Deep Sky Stacker, Levels and Curves in Photoshop
I'm really looking forward to more imaging with this mount and for the first time since I've been observing I want a small apo refractor!