Ts optics max field coma corrector

[bottletopburly]

Does anyone use the Ts 0.95 max field coma corrector? also I assume same as the Altair version rebranded , looking to see what a user thinks of it compared to the baader mk3 cc , images I’ve seen on Astrobin look good 

 

https://www.firstlightoptics.com/coma-correctors/ts-95x-maxfield-coma-corrector.html

[ONIKKINEN]

I used it for a while and have 2 major gripes with the design (mine was TS branded).

First is that it has issues with internal reflections if a bright star is within a few degrees just outside the field of view. See below for examples (the coma cluster one was particularly difficult to remove, almost ruined the shot):

There was another case where i was shooting a comet but cant find the data now. It was garbage so might have deleted it but it had a reflection across the center of the image from Pollux a couple of degrees outside the FOV.

The second is that it doesn't do a very good job as a coma corrector. Never saw good sharpness across the frame no matter how much backfocus searching i tried. In order to get decent stars across the entire frame i had to focus using a star in the outer third of the field of view. That is obviously a compromise as it means the center stars are not at their best focus. To be fair it wasn't awful, but still there are better options at similar prices (such as the 1.0x GPU) so lets say i do not recommend this one.

I upgraded to a TeleVue Paracorr and yes i know its literally twice the price so not a fair comparison but my star sizes measured in arc seconds improved by 20-30% compared to the Maxfield. On axis performance improved even more, but since i still need to focus with a non-center star the center sharpness has limited benefits.

 

***Forgot to mention that my scope is an f/4.4 one, i have seen mentions online that the corrector does a much better job for f/5 primary mirrors. Apparently something to do with spherical aberrations being introduced with faster mirrors.

Edited April 7, 2023 by ONIKKINEN
forgot scope

[bottletopburly]

4 hours ago, ONIKKINEN said:

I used it for a while and have 2 major gripes with the design (mine was TS branded).

First is that it has issues with internal reflections if a bright star is within a few degrees just outside the field of view. See below for examples (the coma cluster one was particularly difficult to remove, almost ruined the shot):

There was another case where i was shooting a comet but cant find the data now. It was garbage so might have deleted it but it had a reflection across the center of the image from Pollux a couple of degrees outside the FOV.

The second is that it doesn't do a very good job as a coma corrector. Never saw good sharpness across the frame no matter how much backfocus searching i tried. In order to get decent stars across the entire frame i had to focus using a star in the outer third of the field of view. That is obviously a compromise as it means the center stars are not at their best focus. To be fair it wasn't awful, but still there are better options at similar prices (such as the 1.0x GPU) so lets say i do not recommend this one.

I upgraded to a TeleVue Paracorr and yes i know its literally twice the price so not a fair comparison but my star sizes measured in arc seconds improved by 20-30% compared to the Maxfield. On axis performance improved even more, but since i still need to focus with a non-center star the center sharpness has limited benefits.

 

***Forgot to mention that my scope is an f/4.4 one, i have seen mentions online that the corrector does a much better job for f/5 primary mirrors. Apparently something to do with spherical aberrations being introduced with faster mirrors.

Thanks for that , intresting

[Turbocoo]

Ive been using the ts maxfied for a few years now and ive found no problems at all. No reflections and stars correct across the entire fov.

Ive recommended this cc on numerous occasions escpecially when i see people mention problems with the Baader spacing and tilt.

I use 56mm spacing with an Asi533 on a 130pds