CraigT82

Cosmetic correction in PI, or a bad pixel map in APP sorts it out very nicely.

Looks like coma since the corner stars have tails that radiate from the centre. Are you definitely measuring the spacing from the FR to camera sensor correctly?

Some super fine detail in that one Neil, and the face of a little green man hiding in the shadows?!

You can get it closer, you just need to use T2 thread spacers to fine tune the stopping point for the OAG as it screws to the filter wheel. You need to OAG turret to stop tight at the 'thin edge' of the filter wheel (as per pic). Is there any shiny surfaces or edges on the inside of any of the kit in the imaging train?

Nice idea for a thread. For me it's probably this image, captured at 4am during the waning phase it is a mosaic of 6 panes, each one was best 250 from 2500 frames I think. Captured with 8.75" Fullerscope at native FL (1620mm) and Altair 290m (red filter). Meant to capture the whole moon but ran out of disk space!

Absolutely Neil, so many differing opinions on what makes a great lunar image it is impossible to please everyone. I actually think that something halfway between the first and second image is what, for me, would be perfect.

Fantastic Neil, I think I prefer the second one

It most certainly is!

Thanks Mike. It is hard to beat a long newt for this kind of work. Not easy to keep them pointed in the right direction though... need a beefy mount! With the Copernicus image I think I'm getting the absolute best out of the scope there (having measured the smallest visible features in LROC map viewer, I don't think it could capture any smaller). I guess that having a set processing workflow I would need consistent data quality for that to work, and I certainly don't get consistent data yet... maybe with a bit more experience and more consistent skies!

Certainly looks like field curvature.Is the reducer also a flattener?

Excellent Neil! Don't think I've ever gotten a decent image of Petavius myself. Did you ever use the fan cooling on the hypercam?

That is a beauty all right! Really nice work. Which OAG did you end up with?

Thanks Neil. I'm sure your 10" will be up and running soon. Yes I know what you mean about the washed out look... The Copernicus image is suffering with this but it was looking harsh and I felt I had to dial back on the contrast. I really need to write down a processing workflow and stick to it for consistent images, as currently I just wing it and see what works which leads to images looking nothing like each other. My favourite out of these three, aesthetically speaking, is the Montes Caucasus one, which is ironic as that was captured under the worse seeing of them all!

That doesn't look like IFN to me, I'm not experienced enough to say if it is bad calibration or not but hopefully someone wil be able to chip in with more thoughts on what the issue may be. I had a quick search on Astrobin for images of M106 which show IFN and couldn't find any. This one is 10 hours with a RASA 8 and 2600mc and if any image was going to show IFN it would probably be this one... https://www.astrobin.com/full/pdyn75/0/

Have missed out on the recent run of clear skies due to work commitments so have consoled myself with going over old data to see what improvements can be had. First is Montes Caucasus region with craters Aristoteles and Eudoxus. 8 75" Fullerscope and Altair gpcam 290m, red filter used as seeing was poor. Next is Ptolemaeus region, again with Fullerscope but with Altair 224c (desaturated). Last is Copernicus, again with Fullerscope, Altair 290m and green filter. Good seeing for this one. (Quite a heavy crop around the crater). Cheers

You don't really *need* tracking at all (although it definitely makes things easier). If you have something like an AZ4 you can manually track the planet with your mak, well you don't so much track as place the cameras FoV just in front of the planet and let it drift through whilst capturing, then reposition amd repeat. I got this Jupiter image using my 200mm f/6 newt on a skytee mount (2.25x barlow and an old imaging source DFK21 camera). I captured about 10,000 frame in total, of which there were about 4,000 that had the planet in it. Used pipp to auto detect and centre the planet in each good frame and then stacked best 25%.

If the secondary is glued across it's full width to the secondary holder it can cause stress in the mirror, when the glass and the holder material cool and contract at different rates at night. This shouldn't be the case though if it hasn't been messed with by someone previously... it should be fine if it is as it came from the factory. If it is tilt you're concerned about you can confirm it by downloading CCD inspector (you get a 30 day trial period) and running the images through that.

Your stars look a bit triangular to me, indicating the primary mirror might be being pinched by the clips. Edit: could also be the secondary mirror if it isn't attached to its holder properly.

I think the green came in around 2017. Current price for a 200p (not pds) on an EQ5 Pro goto is around £1050 I think, but the owner of this scope/mount wouldn't have paid that (prices have gone up considerably recently). Wayback machine shows the 200p on the EQ5 Pro goto at £729 in April 2016.

Yes it would be 2000mm. To get an accurate value you could snap a shot of a star field and upload it to astrometry.net and it will give you the focal length (SCTs have a varying focal length depending on the focus position)

In your shoes I'd probably use a 2.5x or 3x amplifier. For hi res work you need to make sure scope is as collimated as you can get it and that it is cooled and thermally stable. Consider fans and/or wrapping of the tube. Also need to consider what you're shooting over and try to avoid houses or car parks. Shooting over fields is better but may not be possible for you. Try to image when the moon is up high, I've got my best images up above 45 degrees although nice results can be had when lower. If seeing is so-so then use red or IR filters. Good seeing might call for a green filter and excellent seeing might support a blue filter for the finest resolution your scope can give. During capture you want to ignore the histogram as Vlaiv says. You dont want any blown out highlights so keep an eye on the rims of craters etc. The image will look dark in the preview when properly exposed, but with processing a lot of detail can be teased out of the shadows. Focusing is critical so spend time on that. Don't bother with bhatinov masks or any focusing aids... get the preview image zoomed in and watch the fine details carefully as you rack the focuser in and out through the focus point. Make small adjustments and observe the image carefully after each adjustment. I would say that motorised focus is essential. You don't need huge capture sessions really, I find that 5000 frames captured and stacking maybe 500 best frames yields good results. Hooe that helps, good luck!

Helen Sharman on Mir?

What kind of images do you want to achieve? Close in shots of individual features or full disk?

Perhaps you could experiment with blending some Ha into the O3 channels for the HOO. Not sure what you use but APP is excellent for doing this quickly, with sliders for each channel to control the blending/combination.

Tell me about it! Unfortunately it's what I've got to work with at the minute. Linux is definitely in my future once this pair of Windows machines I have are on their last legs. I wouldn't go for the AsiAir though, being locked into ZWO cameras is not something I'd want. Stellarmate looks good though.