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Thanks Vlalv, that gives me something to measure it against. John

The image above was taken using about 25 subframes using a Sony A7III camera, a Celestron C8 EDGHD with a .7 reducer, and a Celestron CGX-L mount.   Early last fall I bought a C14 and put it on my Celestron CGX mount. That telescope with a diagonal, eyepiece, and a finder scope takes it just about to the limit the CGX can carry. I had to buy an extra 17 pound weight to make it work, but for visual astronomy it did fine. When I tried some short exposure, unguided imaging, there were a few issues. There was a slight wind and there were horses in a small pasture 50 feet away. Any breeze would elongate the stars. Every time one of the horses stomped its hooves, the photo looked like every star had an identical double right next to it. I don’t think any mount will keep a telescope stable with large animals making the ground vibrate but it might help with the wind.  I decided to drain the rest of my savings on a sturdier mount. The basic structure of the CGX and CGX-l mounts are identical with a few differences. The CGX-L has a much more substantial tripod. The worm wheels for declination and right ascension have about a 50% larger diameter. The counterweight shaft is 31mm rather than 20mm for the CGX. After using my new CGX-L for a few nights at star parties I can say it is noticeably more stable with my C14 than when I was using the smaller mount. The best part of my CGX-L mount is how good it is with unguided tracking. I did some imaging with my C14 with a .7 focal reducer at exposure lengths between 10 seconds and 45 seconds. Most of the the  photos had round stars and were usable. When I put my C8 on the mount and did some imaging it was better.  Nearly all the subframes were usable, and I was imaging, unguided, for up to a minute. From now on I will likely use my C8 for the bulk of my imaging with the CGX-L mount, and use my C14 mostly for star parties and staring at faint fuzzies, gas giants, mars and the moon.  I recently upgraded my guiding system and haven’t worked out the bugs yet, but I can’t wait to try out the C8/CGX-l combination with guiding. It should come as no surprise that ta C14 that has a focal length of nearly 2800 mm, with a .7 reducer, is going to be less forgiving than nearly any other scope. Overall I am very pleased with my new mount. The CGX-L has no backlash and doesn’t seem to mind if the balance isn’t perfect. I can’t tell you how well it works with auto guiding because I haven’t tried it yet, but I am hopeful that it works well. The only downside of the mount is the CGX-L tripod is three times as heavy as the CGX tripod and the mount itself is no lightweight. lugging the three 22 pound counterweights around is a bit of a workout. It is fortunate the mount head has carry handles that make it much easier to handle than other, lighter, mounts I have owned.   

Hi just in case your interested I have put my skywatcher 150/750 on the sky scan 2001 EQ3-2 up for sale , it's nice scope been flocked  and the rubber O rings been removed and springs fitted to make Collimation easier I fitted clock motor so it tracks , the mount is the heavy duty one not the cheap EQ1 or EQ2 It's £110 which is what I paid for it the motor was £50 so I am not making anything on it . It's on eBay for £150 but as a SGL member you get it for the £110 you can ring me 07564238825

To get higher contrast and sharper pinpoints by totally eliminating the central obstruction.  An off axis reflector (or large reflector masked between secondary vanes) gets you pretty close to that experience.

I have one as my signature say. Got it maybe in mid October.  I was bit worried cause it's most likely 51 glass not 53 or they would say. But I thought colour would be worse but its was very good. On the Abbie rating it's about 87% but it is kinda long at f8. I would have loved a 53 glass even doublet at f8 Joejaguar