AstroMuni

In your image there is a gradient, hence why some parts are looking bluer than others. I use Siril in which you can remove gradients as the first step and then you can slowly stretch the image to bring out the nebula. It also integrates with Starnet so you can stretch stars and nebula independently. I am sure Affinity photo also allows most of these.

Have you tried stretching the image a little bit so M57 is clearer and doesnt get confused as a star? If you are more interested in M57 rather than the full fov try cropping before you apply Starnet. M57 shows up as a small circle in my FOV so I crop heavily before processing. Here is one I took a few weeks ago (around 30mins worth). Processed in Siril no starnet. Steps: - Background extraction - Crop (you could do background extraction after the crop too) - Asinh stretch to bring out colour - GHS stretches to gently tease out details. - Noise reduction - Remove green noise (if needed) - Improve saturation (if needed) Good luck!

Thats a lovely image. What is your process flow in Siril?

Its worth posting your settings on the INDI forum so others maybe able to help you. The Focus module has been improved considerably in the last few months so it will be good feedback to the author(s).

I love the way you have got the mask to be placed and removed. 👍 Are you finding that the Ekos focus module is NOT giving you the right focus without Bahtinov?

Very good points 👍

if its the 130pds then the FL is very close to 650. The shorter tube is just to allow cameras enough room to reach focus.

In my experience I get trailing if I increase exposure beyond 30s without guiding on my HEQ5 pro. On some days I can get upto 60s but thats rare. So I am guessing that with decent polar alignment you should be able to get around 30s too. Try using a Y mask or a Bahtinov mask to improve focus and at a later point you could invest in a Coma corrector to improve the elongated stars in the corners. Good luck!

There are a couple of alignment screws on the base of the focuser that allow you to adjust the angle. Is that what you are looking for?

Great idea. I line the bottom of the tray with coarse sponge and this allows me to arrange the small items in different positions to coordinate the sides I removed them from etc. It wont survive a bump but light nudges dont affect it. Turkish towels work as well.

I have used this OTA extensively and you can see a few images taken with this in my signature link. As to whether it has a spherical or parabolic mirror - I have no clue. But images of DSOs come out pretty decent I must say. Focuser is tricky to use manually as there is no fine focus and it can be wobbly as well. EDIT: I even managed to attach the ASI533 pro to it (no coma corrector) and imaged these. So good luck and look forward to seeing your images 🙂

My understanding was it should be an ellipse (atleast serving from memory of good old orthogonal projections 🙂 ). Like this https://en.wikipedia.org/wiki/Conic_section#/media/File:Conic_Sections.svg Am I missing something here?

Sorry, didnt understand this. Can you explain please?

Heres another way to look at the problem - which scope works best with the camera(s) that you have. If you put your camera details into the astronomy tools calculator you can play around with changing the focal length and binning to get a range of focal lengths that are optimal. This way you may actually end up spending a lot less and getting an additional scope instead of additional camera 🙂

I found this software which works on your android phone and allows you to control your INDI devices from it. It seems to have features to control the mount, camera and use PHD2. Has anyone tried and used this?

You would hope its the other way around as the secondary is harder to collimate 😞

I think you have said it in a nutshell - we never stop learning! Book or no book....a lot of the stuff that I learnt as a student is either out of date or more new discoveries have been made. Just in the last few years software like NINA, Kstars, Siril and several others have come along and are now taking over from the established software products of the past. CMOS cameras are changing the way we image as compared to CCD. So its all about keeping up with change 🙂

Have you looked at the ASIAir ?

To add another grenade 🙂 ...if you are a Mac/Linux/RPi user you could use Kstars/Ekos for planning and control. If you are a windows user you could use it for planning. You can tailor the planetarium to look plain or add the full DSS map view.

Thats a great start...As others have said try adding a UV/IR cut filter and see if you can reduce the FWHM on the stars to improve focus. The aim is to get lowest FWHM ie. sharpest stars. 🙂 Good luck.

Where in the train is your OAG? If you put OAG first thing after the scope and then CC, DSLR you should be able to get backfocus is my guess?? Guiding doesnt need coma free stars

The overall image is looking much better. I think the reason for the oval shapes in the left hand side is a combination of tilt and collimation. If you are getting similar ovals on the right hand side which are like mirror images of the ones on the left then you will also need to look at adding or remover a spacer between CC and camera. And as alacant says, take a look at your processed images and decide if you still wish to improve it.

I suspect the circle is as a result of a combination of focuser tube being too far inside (as vlaiv said) and the fact that you are now capturing the image thro a 2". In the 1.25" image this circle would still have been there but closer to the edges.

Lovely image for an untracked mount. You should be proud of yourself 👍

Very nice image 👍