Possible Issue with new OTA

[Joshua Bunn (Joshua)]

Originally Posted by Ryderscope

Further to your point Glen, attached is a diagram from the Askar site on the FRA300 that shows the way that the OTA focuses the different wavelengths. If I am correct in interpreting this diagram, it is indicating that the blue light is focused differently than the red and green. If this is the case, it could explain why the blue channel is affected more so by tilt.

I don't believe this is the case Rodney, its just indicating, in a rather crude way, that off axis light is focused to the same plane, mostly flat field.

[AdamJL]

Hey Rodney. How did you go getting this issue sorted?

[Ryderscope (Rodney)]

Originally Posted by AdamJL

Hey Rodney. How did you go getting this issue sorted?

I’ve had to hit a pause on this one at the moment Adam as I’m away travelling and won’t be back until the beginning of May. My intention is to make sure that I can eliminate (as much as is practicable) the tilt from the image train before I make the final call on the performance of the OTA. Joshua Bunn has made up an adapter for me that will allow me to use my ZWO tilt adjuster in the image train and the adapter is waiting for me at home now ready for my return. I will be exercising this as soon as I get home and will report on progress forthwith.

Clear skies,
Rodney

[AdamJL]

Good luck with that Rodney.

In the meanwhile, they've come out with something that allows you to interchange the objective as well.

https://www.sharpstar-optics.com/Products_1/75.html

Full kit apparently USD 1695.