Recent Activity

Off-axis Guider…the first year

Over the 2021/2022 winter I bought a ZWO OAG. I spent those cold months figuring out how to incorporate this device into my set-up. My post Adding an Off-Axis Guider to my Set-up goes into lots of detail regarding back focus requirements for my two telescopes (Celestron 8” EdgeHD SCT and a Skywatcher BK80ED refractor). It wasn’t until May that I finally got a chance to use my set-up “under the stars”. Don’t let your imaging camera drop to the ground! My post “First Light” using an Off-Axis Guider explains…

CaLIGHTs Version 3.1.8.2 released

I decided to stay with a 32b application for this version of CaLIGHTs. Microsoft had discontinued support for Windows 7 a while ago but I just learned that Microsoft has made changes to Windows 11 that prevents programming environments from building applications that can be supported not only for Windows 7 but for all 32 bit operating systems. The error messages I have seen indicate that the minimum requirement is now Windows 10. I didn’t want to leave Windows 7 users or 32b operating system users out in the cold…

Optimum Exposure Times

This tends to be a “Holy Grail” kind of topic. I have experienced far too many evenings where I have imaged for hours but the sky glow corrupted the images so badly that the images were not usable. I end up asking myself “would a longer exposure been a better choice?” or “was this just a night to keep the telescope in the house?I decided that I need to research this subject more. I have read lots about “swamping the Read Noise” which sounds like a good scheme. If I…

First Light with an O III Filter

When I bought my first Telescope in 2011 I also bought a BAADER O III filter(10nm) and Light Polution Filter. I had never tried out the O III filter until a few nights ago. The moon was full so I would typical avoid deep sky objects. I decide to try the O III filter because it is a narrowband filter. I decided to image the Crescent Nebula with my 8″ EdgeHD scope at F10 (2032mm FL). I had previously imaged this nebula a few weeks ago using my OPTOLONG L-eNhance…

“First Light” using an Off-Axis Guider

Finally the weather cleared and warmed up. I had been fiddling with my off-axis guider(OAG) set-up during the daytime and I made one revision which I really like. Originally I was using a 1mm diameter wire as a spacer between the OAG and my filter slider. This wire seemed too flimsy and it was not big enough to cater for using a 3mm plastic shim. There was just barely enough threads left on the M42F to M48M zero clearance adapter to thread onto the filter slider. I had ordered Baader…