2 replies to this topic

[Martin Bonadio]

Hey all,

 

Anyone here using a the above FR/FF on their APO. I have a 90mm WO Megrez f6.9 with an ASI183MC camera and looking for a good option for a reasonable price.

Seems well suited for my scope.

 

I'm considering this or the Hotech SCA (flattening only). I like the FR option to help reduce imaging time and widen the field a little. But most importantly want a nice flat field quality across the image..

 

Welcome any feedback.

Edited by Martin Bonadio, 20 January 2021 - 04:23 PM.

[bobzeq25]

Hey all,

 

Anyone here using a the above FR/FF on their APO. I have a 90mm WO Megrez f6.9 with an ASI183MC camera and looking for a good option for a reasonable price.

Seems well suited for my scope.

 

I'm considering this or the Hotech SCA (flattening only). I like the FR option to help reduce imaging time and widen the field a little. But most importantly want a nice flat field quality across the image..

 

Welcome any feedback.

Feedback.  Different scopes have different field curvature.  So, generally need different FR/FFs.

 

The best choice is always the manufacturer's recommendation for a specific scope.

 

The drawers of imagers are littered with mismatched FR/FFs.  DAMHIK.  <smile>

[Martin Bonadio]

Yes, that's great... Unfortunately, Williams does not have a focal reducer specifically for this scope.  In fact I sent them an email asking what they recommend and got no response back. And, we all know that the "best" choice isn't always what the manufacturer says anyway - that goes for telescopes and other things in life.

 

Even their own 6A-III is designed for their Z-series latest line-up, and it was designed to screw into the focuser unless you but their adapter for 2" slide-in...  

 

So we can rule that out - which is why I am asking in the first place... I'm guessing there are other WO 90mm Megrez owners out there who can weigh in on it.  I'd be interested in what they have experienced. I did see a thread from a while back from someone owning an older f6.3 version of my scope who tried the WO 6A-III and said it caused stars to have a dimaond like shape that he wasn't really keen on in his images. So I scratched the idea of a manufacturer specific FR/FF.

 

Otherwise I'll make a call and try something.....

Edited by Martin Bonadio, 20 January 2021 - 04:23 PM.