FSQ-85 .73x +full frame

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Dan Brown avatar
Howdy all. Could someone shed some light on the image quality of this combination, Takahashi FSQ-85 with .73 reducer and a full frame camera? This would be a good angle of view for large subject matter like Rho Ophiuchus. 
Thanks,
Dan
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Bruce Donzanti avatar
Hi Dan

I use a full frame camera (ASI6200mm) on my Baby Q but I only use the 1.01X flattener with it.  I have had no issues with this combination and have posted a few images with this setup on AB.  

Bruce
Larry S avatar
Dan,

I tried the Tak .73x QE reducer with my Baby Q and did not achieve satisfactory results with anything bigger than a 1" sensor (ex. ASI183). For 4/3, APS-C, and full frame it was horrendous. Terrible star elongation, and I could never resolve it by back-focus adjustment (shims ad infinitum). Even with 1" sensor, tilt was a problem (QE reducer grub screws?) I could not resolve. Finally sold the reducer and now only use the 1.01x flattener for good results out to full frame DSLR. 

I thought about trying the TKA82580 CR 0.73X Reducer (no grub screws, so maybe less tilt problems), but they are hard to find and expensive. For now, when I want wide angle images, I am using the Samyang 135 f/2.

I would recommend mosaics with 1.01x rather than using the 0.73x QE reducer.
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