Anza Trip August 2013
The new moon falls on a Tuesday in August which means that I can plan for two trips to Anza this month. The first one was the weekend before the new moon and the second one the weekend after the new moon. This doesn’t happen often so I will take advantage of it.
On the first trip I arrived at Anza on Thursday afternoon and I needed to make an equipment change to my pier. My pier is set up with an adapter for my Losmandy G11 mount however I just recently purchased an Astro-Physics AP900 mount. I needed to remove the G11 adapter and then drill/tap the pier for the new AP900 adapter. Thankfully it went well and quickly as it was about 90 degrees with no shade where I was working. Buying new equipment is an exciting time but also a little challenging with the new learning curve. Not content with the new mount learning curve I also changed my guiding scope setup and added an electric focuser to my Televue NP101! I did get a chance to do some practice runs at the house but there is always a little nervousness with different setups at remote sites. During the test runs at home I imaged the Crescent Nebula using the Hydrogen Alpha filter and 20 minute exposures. The new mount was just awesome; it just worked and worked well. The new guide scope setup was rock solid and I did get it to work well after some tweaking of the settings in Maxim DL. I really like the FeatherTouch focuser by Starlight Instruments and the MicroTouch electric motor with control by FocusMax. The electric focuser was the last piece of equipment required to automate my imaging setup. I plan on trying the automation software in the next month or so and I will do a write up on that experience at a later time.
Thursday night looked to be a good night with clear skies and no wind, however looks can be deceiving. I was not happy with my focusing statistics so I checked around with some buddies and they were having the same experience. The best focus I was getting was 3.48 FWHM and I usually get in the high ones or low twos. There was some atmospheric disturbance that was affecting the ability to get good focus. From past experience with this focusing issue I didn’t want to start imaging right away so I decided to do some image testing of two potential targets. I moved the scope to the Barnard Galaxy and did three 20 minute exposures in RGB and to my surprise I did get some good data. This is a dim irregular galaxy usually imaged with much larger telescopes but I wanted to give it a go. Satisfied with my result I decided to image this object the following two nights. Why not tonight? Well the combination of atmospheric disturbance and a dim object spelt a waste of an evening. The detail would not be there and the object would look fuzzy and washed out. Next I moved to the Helix Nebula and set up some 10 minute exposures. I chose 10 minutes as this is a much brighter object and initially I liked what I saw but I thought I could get more data with 20 minute exposures. But with the atmospheric disturbance still happening I made the decision not to image the Helix Nebula tonight using 20 minute exposures. However, I was not happy just shutting everything down and calling it a night so I set up a series of 10 minute exposures on the Helix Nebula and let it run the rest of the night. The next morning I started processing on the Helix Nebula and my hunch was right. I needed 20 minute exposures for more detail and the atmospheric disturbance caused the data I had to be soft and appear slightly out of focus. Oh well, not a total waste of a night because I now had a good plan for my two targets.
Friday night was just awesome. The atmosphere was playing nice so I moved to the Barnard Galaxy and set up for 20 minute exposures in RGB. I imaged for 6 hours that night and everything went smoothly with the new mount, focuser, and guiding setup. I woke up on Saturday and did a quick processing run and was happy with the results.
Saturday night was more of the same and I captured another 6 hours of data on the Barnard Galaxy using 20 minute exposures in RGB.
I like to get on the road early for the trip home so I packed up and was on the road by 6:30am. Excited to see my results I started processing my data shortly after I arrived home. Here is the result of 11 hours of the Barnard Galaxy.
Well the first trip of the month went well considering I was using a new mount, new electric focuser, and new guide scope configuration. The Astro-Physics mount is just a work horse that can handle a lot of weight and operate with precision that I did not see with the Losmandy G11. This is not a knock on the G11 as it is a fine mount and very capable of long exposure astrophotography. I have used the G11 for a year now and many of the pictures on this site were captured using this mount. It is just that the AP900 is in a different performance and price class. The new focusing motor has been a nice addition and it was very easy to install. I am using FocusMax in conjunction with Maxim DL to control the focuser and it was very easy to calibrate. I have not tried the temperature compensation feature yet but it sounds like a great feature if I can get it calibrated correctly. Finally, the new guide scope setup consisted of replacing the Orion mini guide scope on a mono point connection with my 65mm refractor on a dovetail and quick release plate. The dovetail plate and dual mounting rings on the 65mm scope are rock solid and have eliminated any flexure issues.
My target for the second trip will be the Helix Nebula using 20 minute exposures in RGB. I am using these parameters based on my testing from the previous week. I will do a brief write up when I get back.