Antonio Parisi:
Hi I am currently using a Takahashi fc100dz with a Sony alpha IV looking for an astro camera...I'm interested to know why you Dan is talking about Full frame up there and Jeremy why did you get the 107?
I'm try to evaluate whether the apsc would be a good fit.
Many thanks to both.
I saw this video from Nico Carver and the ff107 looked great for an APS-C sensor...
https://www.youtube.com/watch?v=G1zM-lz7Fx4I wasn't so convinced with his full frame sensor results, but I am using a smaller APS-C (ZWO2600MM). I have used it for one night so far, so no images to show yet, but the stars on my subs are perfect right to the corners and, being a quadruplet, there was no messing around with back focus, as you don't need to worry about it. Testing the images with PixInsight's Aberration Inspector is a very harsh test, but using this I can see the stars are perfect when pixel peeping. The optics seem great and it is nice and potable. I think the 749mm focal length is in the sweet spot for me also. Good luck with your choice.