Tim replied to the topic 'What is considered good guiding?' in the forum. 3 months ago

I too have a CEM120EC. I normally get around 0.75" RMS going down to 0.25" on a really good night and once everything has thermally stabilised. My seeing is rarely better than 1" and my imaging setup is 0.8"/px so I do not worry too much. I have more problems from optical sources (poor collimation, CCD plane etc) than from guiding. I do take care to physically balance my twin rig on the mount, using dummy weights to help me move between configurations. I also have an old HEQ5, used for wide angle work (24mm DSLR lens + SC694) and get about about 1.5" RMS on that for an image scale of 38"/px! On both setups I use the Ekos guiding module, with long exposures and correction periods (typically 10 secs).