I have a couple of friends who are considering investing in a 5 inch apochromat. Both are influenced by viewing in my Zeiss APQ 130. Both gentleman are thinking about a Tak FS 128.
My question is how do these two telescopes compare at the eyepiece. I realise a tiny bit of residual chromatic aberration will be in the FS 128. But being a well coated doublet will the FS128 have a small edge in contrast and perhaps image brightness over the triplet air spaced TOA 130 ortho apochromat??
The FS 128's sure seem to be a bargain at present with folks selling them for well under 4000US second hand and being 4400 or so new.
Both are around f-8 and the FS ota has less mass by a couple of kilograms too.
Anyone done a comparison on say planetary performance??