oymd

Oh, I did not know that...so I should de-focus in both directions then? I did defocus all the way out, but I never say a doughnut similar to the one you kindly provided in your image. It went from a doughnut to completely disappearing. I used my camera and PC. Is it a pre-requisite to collimate using an EYE PIECE rather than PC and camera?

Thank you Peter fr your reply I am using a camera and the PC for the collimation. Can you please clarify what you meant by "very high power" and "almost focussed"? If the star is almost focussed, it would be tiny and pinpoint on the screen, and I would not have a doughnut? Apologies, I am new to this, and I do not follow?

With galaxy season upon us, I've decided to give my C8 a go. The OTA is 2 years old, very lightly used and I had never collimated it before. To check that my collimation is ok, I used NINA to slew to a bright star, plate solved and centred, then I moved the electronic focuser out of focus. I could see the doughnut and it looked centred to me, so I left it alone. Am I missing something, or does it look ok? Is that all I need to check regarding collimation? Many thanks

HI Vlaiv What do you mean by East heavy? And by how much should I be out of balance?

@vlaiv Apologies, a bit off topic here. I am also very interested in the Gemini e-Fric, but with the sad news of Andreas passing away a while back, is the mount still in production and supported?

Would this be a good option for imaging?

Good morning Sorry, I am not following? The Esatto 2" focuser has been widely used with the EDGEHD scopes and the reducer?

I'll be immensely grateful if someone can advise on this imaging train. After experimenting with imaging with the Edge HD, mirror flop and shift, I decided to by pass the issue entirely, and LOCK the mirrors, hence purchasing the Esatto. Can you please recommend which adaptor will be used on the CAMERA side? And how to reach correct back focus of 146mm? The OAG I am using is the newer OAG-L, with the 12x12mm prism and 48mm aperture. Camera is the 2600MM mated to the 2" EFW. Here's my imaging train: TWO OPTIONS. One WITH, and one WITHOUT 0.7X Celestron reducer. EdgeHD 11 ===> 0.7X Reducer ===> Esatto 3.3" adaptor ===> Esatto 2" Focuser ===> ?? ===> ZWO OAG-L ===> ZWO 2" EFW ===> ZWO 2600MM Pro EdgeHD 11 ===> Esatto 3.3" adaptor ===> Esatto 2" Focuser ===> ?? ===> ZWO OAG-L ===> ZWO 2" EFW ===> ZWO 2600MM Pro Many thanks

I’ve experimented with various guide exposures. On my AZ-EQ6 I found 2 seconds to be perfect. With this CEM40, anything over 1s, and tge RMS shoots up and PHD2 turns into an ECG of a patient with atrial fibrillation!! But that is just by viewing the graph. I should try comparing FWHM as you suggest!

its when I wobble the CW bar to the left, the Scope and everything on it wobbles to the right, and vice versa. Its barely visible, but can be felt very easily. Tightening the worm/gear mesh eliminates it, but then locks cannot be released

And this is what I meant by the RA wobble IMG-3677.MOV

Thank you so much for your prompt responses 1- With regards to BALANCING, i can say with confidence that it is PERFECTLY balanced. Too balanced in fact. As the ZWO EAF sticks out too much on one side, I attached a short WO dovetail on the opposite side, and loaded it with washers to achieve perfect balance in the third axis. Balancing these CEM mounts is ridiculous! Attached is a pic showing my DIY counter weight for the focuser and my latest calibration after stripping the mount and replacing the belts. 2- everything seems to be RIGID 3- DEC has no obvious backlash. RA has a VERY slight ROCKING/WOBBLE when I manually push the counterweight to one side. IT IS IMPOSSIBLE TO GET RID OF IT. The only way I can get the RA to be solid with ZERO wobble, is to tighten the gear/worm meshing to the point that I can no longer undo the RA lock and I get stiction. Even if I then loosen the meshing by 1/1000th of a turn (exaggeration here of course ), the RA wobble immediately comes back. There is simply no sweet spot where the gear/worm meshing eliminates the wobble, yet can be unlocked and slews normally. I have spent DAYS on this! 4- Tripod is the beefy 2" one, with legs all the way in, and on concrete floor.

Sorry to intrude on the thread, but I want to understand PEC recording and how to apply it to my mount. I am troubleshooting my CEM40, which seems to behave badly in RA, immediately as I start PHD2. It jumps to RMS 1.5 in a matter of 1-2 seconds, NO MATTER WHAT I DO. Mechanically I stripped the mount, changed the belts, have the bearings on order, but still the same behavior. Tried fine tuning the mesh binding between the worm and gear, improved the DEC backlash significantly from >65000ms to about 400ms, get good PHD2 CALIBRATION results, but RA is hopeless. Never better than 1.2RMS With regards to PEC recording and applying, what should I do? In IOPTRON Commander, there is the option to RECORD PE. There is also an option to PLAY BACK the PE. When, how and how long do I PLAYBACK the PEC? From the above, my understanding is to record PE when the mount IS NOT GUIDING or connected to PHD2? My work period is 400s, but in PHD2 it auto corrects to about 800s, when I choose the PPEC alogorithm for RA guiding @vlaiv Vlaiv, would be great if you can help me with this? How to I apply the PEC that I record in Ioptron Commander to my mount's guiding? I've run the PEC recording while guiding, whoile NOT guiding, with PHD2 closed, and it seems to give me random results. I do not have PEMPRO, which I read that is needed for applying PEC recording to the mount's guiding? Imaging is at 350fl, 294MC Pro had 4,63micron pixels, so imaging scale is 2.7"/pixel. Starts are more or less round, and I am actually surprised that the subs look much better than what you would expect when ;looking at the graphy on PHD2, but I know something is wrong. Guide scope is the SW Evoguide, 242FL, camera is 120MM Mini 3.75micron, so guiding at 3.2"/pixel Sorry, so so confused?

Thank you both for your advice! "Slippery slope financially" Show me something that ISN'T a slippery financial slope in this crazy hobby! So, my point is, using any of your two suggestions, will that allow mw to properly image the sun, or it will be some kind of bad basic compromise? They seem to be very expensive options, so want to know if any of them will work well, and give me good solar imaging options? I realise that the high end solar scopes are £££, and I am realisitic. I am not aiming for that. Just a good solar scope for visual, and more importantly some basic imaging. (still do not fully understand solar imaging, but I hope I can get YELLOW images of the sun, not just the basic white/grayscale) Many thanks Ossi

Hello everyone! My first telescope in the hobby was a SW 80ED Pro that I bought from FLO as a kit 2 years ago. After only 2 months of using it I upgraded to all sorts of equipment and telescopes and have not used it since and it has been sat in it’s aluminium box ever since. I do not want to sell it, and would like to convert it to a solar scope. I’m keen into getting a taste of solar imaging, but I find the necessary kit a bit confusing. Is it possible to use said telescope with some appropriate H Alpha filters as a solar imaging scope? Many thanks Ossi