tooth_dr

I have a 120MM that I’ve went back to for guiding, and it does the same as yours, PHD 2 problems with longer exposure times, then it will go back to normal, and also split frames. I just assumed it was the camera, so will be interested to see if you find a solution.

Beautiful result. Well worth the mammoth effort.

Fantastic result, such great detail. I have access to a 14” LX600 and tonight is looking good, plus I’m off work tomorrow so planning a late one. I just bought a 685 filter, and have LRGB filters, in a manual wheel, with a 290MM. I have done any planetary imaging in a long time. Any tips?

I took the epsilon mirrors out last night to clean and recollimate. There were indents on the metal back of the secondary that I rubbed out and then painted black. I was finding that the secondary didn’t stay in the position I moved it too, and perhaps these marks were to blame. It wasn’t that dirty but I cleaned it with water and fairy liquid. The primary was really quite dirty, but cleaned up well. I’m going to get a few heater for the primary and run the dehumidifier more frequently in the dome. Collimation of the secondary was really very tedious to get the spot centred, but I managed it after about an hour of faffing around. I am happy that it is all together looking forward to star tests later

Very interesting!

Depends on the camera. My flats would be similar with my KAF-8300 camera, but you could try an in between brightness acetate. Is the panel at max brightness now when using the grey sheet?

Thanks John. Please yes share the links.

Thanks again Mark. I’m feeling a bit more positive about the whole thing now. Just the slotted screw heads to release

I know pictures aren’t that useful but I think it’s fair to say I’m slightly out. No matter how I tried to adjust the secondary it didn’t stay in position when tightened. And I think or hope that’s due to marring one the secondary back plate.

Thanks Mark. I have the screw on Tak collimating tool - that is attached below the threaded adapter and then I insert the eyepiece in the 1.25” hole. There are quite deep indents on the adjustment side my secondary mirror, marred by the tips of the adjustment screws. These seem to be preventing the final fine adjustments from happening. I unscrewed and tried to lift out the secondary mirror this evening to sand off the marks but I can’t get it through the gap in the spider vanes. I read that you have removed the primary cell. Can you confirm how you did this? On mine the black rear cell appears to bolted on but there are nuts on the inside. These nuts appear to be free to turn. I’ve marked them in red below. Is this correct? The mirror is quite dirty - there is a fan on this scope and it looks like it has drawn in dust and it has stuck to the mirror when dew was on it. I’d like to wash it before collimating the scope. Sorry for the plethora of questions, I’ve had the scope a year now so time to get it working properly.

Ahhhh! That explains that, I was doing some head scratching earlier !

I was using a KAF8300 mono Atik 383+ which has a much smaller sensor. It calibrated 100%, and was more forgiving on the star shapes but I don’t think the scope has been perfectly collimated. The D800 was already owned by me (not bought for astro) but it’s been suggested on here by a few images to start using it with the epsilon. So now I’m here and struggling with it 🤷‍♂️

Thanks Mark. Perhaps I’m seeing that at the bottom? The mirror actually impinges permanently on the image?

Hi Mark, sorry if I have misled you, I have a Nikon D800E.

Another test in CCDI using a different set of images from a different target, do the curved corners indicate collimation issues or spacing issues? I'm on a fixed spacer - NIKON-->TAK screw

Hi John, no I'm not. I tried a star mask but it left artefacts around the stars. I think this is the problem, the stars get massive quickly. Are you aware of any good guides that work for you?

I ran CCDI on 8 subs from above, giving this average:

This is my first time using the Nikon D800E for imaging, and I'm trying to work out where I'm going wrong here. I've attached a master flat and bias, an uncalibrated and a calibrated sub, and the resultant (heavily stretched) stack. You can see the light banding along the base of the calibrated subs, so something isnt working properly, and the flats dont appear to be correcting properly. I took my flats using a tracing panel, diffused with a sheet of grey acrylic. I'm using APP to stack the data. Any help very much appreciated. I dont like to tag people on here but if you have time, would you be able to offer some advice? @mftoet @sharkmelley My stars are not good shapes either so any input on that would also be great. Thanks Adam.

Mark I thought I would post looking for advice regarding using the Nikon with the Epsilon 180ED. I have noticed that glow along the bottom of my bias frames, but it doesnt seem to calibrate out and I'm left with a band along the bottom of stacked image. I took a series of 300s lights at ISO400, and dithered my captures. I then took bias frames and flats at ISO400. I've tried using the bias as darks, and created a bad pixel map, but all combinations of calibration do not seem to be removing the glow. Would you mind if I asked how you dealt with this properly?

Thanks Richard. I will try to collimate it again and if I cant get anywhere I'll swap the original focuser back on again.

It’s funny I switched back to APT a few days ago for multi camera dithering. It is way easier to use. The only advantage of SGP for me at present is the framing mode.

I havent tried the stock focuser, but I didnt want to start taking it apart and making it worse tbh. It may well be that it is better and adequate. I also have the microfocuser for it too. I think I'll try collimating it again using the Tak tools and then see how that goes.

I've tried focusing in dead centre and at 1/3 across the frame - when the stars are smallest according to APT analysis, and also the cross is aligned on the Bahtinov mask, the diffraction spikes dont align. I'm using a 2.5" moonlite focuser but also have the stock focuser. It's certainly in my eyes a collimation issue from reading around the topic. I might need to buy a Catseye collimator.

I focused on the diffraction spikes last night, but tonight i checked with a bhatinov mask. The two things dont correspond. The image below is deneb when in focus with a mask. What does this indicate? Collimation? Good luck for later