I have two setups:
1. William Optics Zenithstar 73 + Flat73a flattener + ZWO ASI 2600mm pro
2. Sharpstar 94 EDPH + x0.8 reducer + ZWO ASI 2600mm pro
I usually shoot with setup 2. However, I would like to get a longer focal length. So I am considering attach Flat73a (which does not reduce focal length) to Sharpstar 94 to get the original focal length (517mm, f/5.5). Sharpstar 94 has M74 threads, but Flat73a has M63 threads. The only adapter I can find in the market is 2-inch push-in to M63.
1. Will I get good result with Sharpstar 94 + 2inch-to-M63 adapter + Flat73a + ASI 2600mm pro?
2. Will the 2" adapter reduce the image circle of Flat73a considering I am using ASP-C camera?
2inch-to-M63 adapter: https://williamoptic...for-p-flat6aiii