Last week-end I was able to go to Anza for the second time. My very first time there, although I couldn’t put anything in the frame of my Canon 500D, went well as I was able to polar align, create a model (using my RDF), track, guide and acquire some data. This was encouraging to me but I was a little bumped I had pretty much no data to process. I figured the issue was my RDF not being collimated with my main imaging scope. Knowing that, I thought I could fix this issue by just aligning my imaging scope and my ST80. After setting up the equipment this was the first thing I did, unfortunately I quickly realized that my RDF was still off both my scopes. I tried to play with the small RDF saddle but I was not able to align it close enough… and it was getting pretty dark already. Then I thought I could just build my model using either scope so I tried that and it didn’t work very well as I couldn’t put any bright (alignment) star in the field of view of the scope. I guess I need a more experienced eye to do that with such a narrow field of view (it’s not this narrow actually but most likely too narrow with my current observing skills).
I ended up creating my model using the RDF (which is still off the imaging scope by what looks like a good couple degrees). After that I decided that I should work on M31 because it’s a large object, and it should be easier to spot than an Ha Nebula. It did take me about an hour to find it, but when I did, I quickly centered it and found a good star in the field of view of the ST80 which I used to guide for the following three hours.
For the purpose of learning and evaluating both tracking and guiding, I started shooting 120 s light frames for an hour. I moved to 300 s lights and finished the night with 600 s lights. After quickly reviewing my subs it seemed like my tracking and guiding were decent which made me happy as it also meant I would have actual data to process back home!
I then decided to look for another target. It was about 2 AM already and M45 The Pleiades were already high enough and I thought they would fit my equipment’s FOV pretty well. Unfortunately, after one hour of trying I still couldn’t find them so I went catching some sleep in the car. I really to find a way to create a model that makes finding my targets a little bit easier. I am thinking of buying an illuminated wide field eyepiece. It means I will need to install my Canon 500D and CP30T-EOS cooler after both polar alignment and modeling are done. I am wondering if doing that could slightly move the mount and induce alignment problems? I guess if I am careful enough it should be OK. I could also find a way to install my RDF to my AT65EDQ. I don’t have much room for that as it’s a small scope and with the bigger ST80 on top of it I think there is a clearance issue. And I don’t know if my RDF will be collimated with the scope either. It’s an Astronomy Technologies RDF, I don’t know if that makes it more likely to be aligned with an AT scope. Still a long journey ahead of me and that’s good! I can’t wait to go back and figure this out. Until then I will start searching what’s the best way to handle this modeling/aligning issue, and I will also update my Gemini 2 firmware which seems to improve modeling a lot.
Here is the final processed data of my first true imaging session: M31 The Andromeda Galaxy. Technical details are listed below the image.
- Camera: Canon 500D Baader Modified and CP30T-EOS Cooled (Sensor maintained at 15 C – Exif temperature: 15 C)
- ISO: 1600
- Exposures: 3 hours total, 1 hour of 120 s subs, 1 hour of 300 s subs, 1 hour of 600 s subs
- Mount: Losmandy G11 Gemini 2
- Imaging Telescope: AT65EDQ
- Guiding Telescope: ST80 w/ SSAG
- Calibration: Darks
- Stacking: I did three DSS jobs (1 for each hour of data)
- Final blending/processing: Adobe Photoshop CS5

Extremely well written read…