Vignetting Solved, (well almost)

[Nicola Hannah Butterfield]

I have tried to cure the server vignetting with my full Canon 6D and Skywatcher 200P using flats, but to no great success, so I had been thinking of an M48 T-mount to 48 mm 2" adaptor, anyway pick up a couple cheap version to test the theory and here is the result, all I have to do now is safe for a cheap 2" lpf and see where it sits in the train.

Both exposures 1/320th f5 ISO 200

[johngm]

Thats a fantastic improvement, and to be fair, I dont think you'll will gain much more if any with the 200p and full frame sensor.

[Nicola Hannah Butterfield]

8 minutes ago, johngm said:

Thats a fantastic improvement, and to be fair, I dont think you'll will gain much more if any with the 200p and full frame sensor.

Just got to wait for some new bolts for the mount (on order), and some clear weather, which has been in short abundance these last 4 months, and virtually non since I got the guide scope bar a quick test with it last Friday. If this all goes well coma corrector next purchase, but before I do that, I want to see what improvement this will make, the improvement should also help in stacking.

The t-Mount is a little loose on the camera but it was on;y a cheap one, I wasn't going to spend £30+ on something that might not work

Edited November 19, 2020 by Nicola Hannah Butterfield

[johngm]

1 minute ago, Nicola Hannah Butterfield said:

Just got to wait for some new bolts for the mount (on order), and some clear weather, which has been in short abundance these last 4 months, and virtually non since I got the guide scope bar a quick test with it last Friday. If this all goes well coma corrector next purchase, but before I do that, I want to see what improvement this will make, the improvement should also help in stacking.

Tell me about it (the weather i mean). I purchased an SX694 pro mono in the summer, with the weather and work commitments, ive managed 1 night (5 hours), of  Ha data on the crescent Nebula 😔

[johngm]

Forgot to add, coma corrector should help. With the improvement you've made though, may be worth trying flats though

[Nicola Hannah Butterfield]

Just now, johngm said:

Tell me about it (the weather i mean). I purchased an SX694 pro mono in the summer, with the weather and work commitments, ive managed 1 night (5 hours), of  Ha data on the crescent Nebula 😔

My last attempts were M32 and M33 in early August. Can be seen here https://sites.google.com/view/nhb-astro-photo-site/deep-sky if they are not in my gallery.

[Nicola Hannah Butterfield]

Just now, johngm said:

Forgot to add, coma corrector should help. With the improvement you've made though, may be worth trying flats though

I do flats usually unless just testing something, like my first 5 min exposures last Ftiday, got two 5 min, one 2 min and 60's of a star field around PU Aur

You can see the stars trailing towards the edges. no flats, darks or bias.

[Nicola Hannah Butterfield]

[johngm]

 Just looked at the images, and most definitely coma in the images rather than vignetting.  More noticeable on M31