I went back to Anza on April 28th 2012 to test this OAG setup. Unfortunately and for the second time it didn’t work as planed. I will update my web page about the OAG soon for more details. But basically, with the CCDT67 focal reducer this far from the sensor (about 90mm) I can’t reach focus even with no extension used.
I took the OAG off and setup the AT65EDQ to guide.
I did keep the CCDT67 focal reducer to see what it can do. With my M42 to M48 adapter, the reduction is about .68x which on the AT8RC gives about 1110 mm of focal length and a focal ratio of about f/5.4.
I had about a couple of hours before the moon set to start doing long exposures of the Iris Nebula and decided to try shooting my first globular cluster: M5.
I started with 2 mn exposures and finished of with some 1 mn to make sure I could get some details out of the bright core.
As usual, technical details are listed below the picture:
- Date: April 28th 2012
- Camera: Canon 500D Baader Modified and CP30T-EOS Cooled (Sensor maintained at 10 C – Exif temperature: 10 C)
- ISO: 1600
- Exposures: ~ 1.5 hours of integration time (120 s and 60 s subs)
- Mount: Losmandy G11 Gemini 2
- Imaging Telescope: AT8RC w/ AP-CCDT67 @ .68x
- Guiding Telescope: AT65EDQ w/ SSAG
- Calibration: Darks, Flats, Bias
- Stacking: DSS (Entropy Weighted Average)
- Final blending/processing: PixInsight 1.7 and Adobe Photoshop CS5