AstroNebulee

Added a 5mm spacer to the imaging train now and hoping the total 60mm of back focus will cure the eggy stars. A few other members with the exact same set up had to use 60mm to cure their issues, so hoping its cured mine too, really need a clear night to test it all now.

Thank you @PatrickO, they arrived today, one book for dummies for a dummy 😉 and from the amazon jungle some spacers, so hopefully I can sort out my eggy star issue once and for all 👍

Hi @alacant here attached is a single 3 minute sub from last night (just a light and dark stacked no flat or flat dark) with my current filter, rotator, ovl field flattener, 55mm of back focus and 294mc pro. If you zoom in, the stars are all pointing from the centre of the image, so I think it needs more back focus. The image is easier to see the issue on a laptop screen as much bigger. Cheers Lee

Hi Steve I replied in the other thread, Alex at flo is kindly helping me with this issue. I bought the scope in the classifieds here last year and camera from RVO as it was in stock there. I'll be sure to let RVO know the issues to. I hope I didn't come across as buying the items from you and complaining at your service, I'm sorry if it did. Cheers Lee

Hi Steve. Thank you. I'm in contact with Alex at flo and he's helping me out. I bought the scope and reducer in the classifieds here last year, so no joy there. And camera from RVO, I'll be sure to let them know too. Cheers Lee

No, I was still getting the eggy stars at 55mm with the thumbscrew focus adapter and FF nose piece. Since then I've recollimated the scope, bought a tilt adjuster and bought an Ed80 0.85x ff reducer which isn't compatible with my scope as its the older one (it would of been compatible if it was the short tube) not knowing if I had the new or old one though. I think it's all to do with the ovl FF and the older 72ed (not short tube) as after a trawl on here a couple of other members on here have the same setup and use 60mm of spacing.

Get rerport Stu, so pleased it went really well for you and a stunning time-lapse. Look forward to the fruits of last nights labour's, brilliant again 👏

Sorry to hear you had an awful session too. I was much the same, trying out my adjustments made during the clouds didn't work out, so back to the drawing board. Needless to say I'll probably be selling the ED80 0.85x flattener reducer I bought as its not compatible with my sw 72ed as its not the short tube version (not enough inward focus) Think I need to add another 5mm of back spacing to my imaging train of sw rotator, ovl FF, 55m spacing then 294mc pro as still getting eggy stars, but this is in another thread. So last night was a complete waste and sacked it off by 8.30pm even though it was clear still. Hoping Friday will stay forecast clear and carry out more tests and will work with 60mm of back spacing, if not my astrophotography gear will be going in the classifieds 😒

Sounds great Stu. You had a good observing session there and be better next time setting up, been there in the excitement and forgot to add my cw once! Thank you for your report and feedback, it's nuggets of info and advice needed on this thread 👍

Hi Rectifying this thread as I've an issue with eggy stars in my images and I'm using 55mm of back focus. Been struggling with this since I got my 294MC pro, am I correct in saying I need 60mm of back focus. Also I purchased a 2 inch zwo ir uv cut filter and screwed directly onto the inside of the rotator. Cheers Lee

Hi Alan It would be just my luck to have a poor example. Regarding astro clubs, I don't drive and live in rural Cornwall so not very easy atall. I don't use the thumbscrew focuser collar, I use a rotator so there's no chance of flexibility in the imaging train. I still on theibrs of thinking a 5mm spacer us needed as I'm sure I saw online somewhere someone mention 60mm back focus for 72ed, ovl FF and 294mc pro. After some trawling on here I've found this thread about the rotator I have and @Skyline @StarlightHunterhas the same set up as mine and uses 60mm back spacing, so sent a pm to ask his advice too. Thikk my 72ed is the oldee long tube version (there's no rotator sticker) but the rotator fits perfectly. I shall add an image from last night as soon as I get home. Lee

Still got the issue with eggy stars after the collimation which is centred. Tried adding the spacers provided with the camera but still the same. The stars seem eggy more uniform now suggesting back focus isn't enough, think I may need 5mm more so 60mm back focus possibly? I'm losing the will to carry on and just accept the eggy stars or give up.

Thanks Clarkey, it looks suspciously like the skywatcher rotator I bought from FLO doesn't it. I've emailed Alex back at flo hopefully hear back moro with some good news, other than that I'm a baffoon. https://www.firstlightoptics.com/adapters/sky-watcher-evoframe-camera-rotator-for-evostar-72ed-ds-pro.html

Quite, that's what I thought too, I'll email @FLOagain to see what occurs. Thanks Clarkey 👍

Yep read that one before too. It says it won't work if you don't use the adapter for it which isn't available separately. The rotator I have is for the short tube 72ed as stated in note 1 on the FLO rotator page some cameras won't reach focus with the rotator but I can with my ovl FF so I should be able to with the. 85x one 🤔 and note 2 is incorrect as you can use it with a ovl FF as many have done in the past. My scope seems to be the old longer 72ed as I've no sticker on the scope suggesting to use a 360 rotator.

I can't fit the reducer flattener to the scope without the rotator. I contacted flo and could connect the reducer flattener to the rotator and scope but think it went haywire as I thought I had a newer 72ed but turns out I think I have the older one which the 0.85X Ed80 reducer flattener isn't compatible. So my bad. @FLO

Hi Whilst trying my adjustments tonight and first light with my. 85x FF reducer I didn't have enough inward travel on the focus tube to reach focus. I'm using a sw 72ed AzGti eq mode. Then attached to my focus tube is the rotator from FLO (a 2 inch zwo attached to the rotator scope side) then the 0.85X reduced FF, then the 16.5mm spacer, then the 21mm spacer then tilt adjuster which adds up to 55mm from sensor to FF. But I still have not enough inward travel, do I need an extension someone in the imaging train. Sorry for sounding thick. I couikd reach focus before with my ovl FF and same set up. I'll attach a picture of my imaging train.

Good luck tonight, hope all goes well Stu and the filter performs better than the svbony one, was nice on my set up when used 👍, hoping for some clear skies myself tonight if the reports are correct, to test out my alterations

I think you are correct, be an awesome scope in EQ mode too, I'll look forward to the report 😊

Sounds fantastic Stu. You've got some great targets planned there, good luck, can't wait for your images and reports from the obsy first light👍

Looks very nice indeed Stu. Definitely be great for the az gti in alt az. Hopefully you'll get first light this week and the bigger aperture be great. Eager to hear how you get on with the scope on az gti 👍

Brilliant to see your obsy ready to go in your video yesterday. Whilst watching everytime you told your alexa to do something in your obsy, you kept waking up my alexa haha, good luck for Tuesday hopefully and look forward to your results 👍

Thanks Olly, I see what you mean now too. It makes sense, just what I've learnt to say. I will try to fall on the flat dark side of the fence now. 😊

I apologise, I'm new to this myself and a bear of little brain 😔 I'm only following what the dss says about stacking without bias frames, the screenshot is from the dss help section, not my own workings, I've always said dark flat and no one picked up on it before or corrected me.

Haha no, just my inability to explain what I meant (note to self)😁