New fra400 any tips from owners? - Forums

Topic starter

Sep 24, 2023 · Edited: Sep 24, 2023

Just bought an fra400. Ive looked around the internet for issues you might run into with this scope, only saw halos with osc camera and narrowband filters. I will be using a qhy268m with cfw3 and astronomik deep sky rgb with astronomik l3 lum.
just looking for anything owners of this scope would reccomend for the flattest, abberation free images with an aps-c sensor.

RammaN

Topic starter

Sep 24, 2023

Also for now i am not using the reducer but i would like to try it if the field is properly corrected for a 28mm image circle.

Michele Campini

Sep 24, 2023

Since Sharstar say that with 0.7x field is corrected for FF sensors but IMHO with an APS-C (asi2600mm) field is not fully corrected.
No problem at full focal lenght. The same with the fra500.

Matt Simmons

Aug 27, 2024

Just bought an fra400. Ive looked around the internet for issues you might run into with this scope, only saw halos with osc camera and narrowband filters. I will be using a qhy268m with cfw3 and astronomik deep sky rgb with astronomik l3 lum.
just looking for anything owners of this scope would reccomend for the flattest, abberation free images with an aps-c sensor.

Yes, lower cost OIII filters will cause halos, especially with the reducer. Image circle with the reducer produces a very small, manageable amount of vignetting with my 2600 cameras.