Thank you Randy.
I roughly processed yesterdays data. The data was minimal, 3 subs on Ha,O3,S2, Only Ultra-quad monochrome file was 6 frames. -25degree C, 300sec each. 6 frames was lost by the cloud passing.
This image is applied Ha to R, O3 to Blue, S2 to Green. L is QB.
To see the data, AF equipped star looks very fine. Tonal rendition also looks fine. Though at first nebula centering was O.K. for some reason I did not noticed the shifting to the west direction. Anyway, it's only the test, I had to talk myself.
FCT-100 was designed as visual telescope upgrading FC-100, though Mr. Kiichirou Takahashi insist to design as fast and wide field 6*6 APO camera.( I still have that 6*6 film holder) At 1985, there's no such telescopes in the market. Indeed, Pentax ED 100 F4.0 may be the contender, but it was not the telescope. FCT consist of traditional triplet and gorgeous triplet reducer, it inherently had the difficulty on sagital coma correction. You'll see it in this photo. May be that's why they moved to Petzval design.
Double doublet have the advantage of Petzval sum theory. In reality, FC-76+new reducer surpass FCT-76 + triplet reducer. To upgrading the FCT reducer, Mr. Yuyama say, 'strong meniscus will be needed', like 0.72c FS-60 reducer. Anyway, to see this image, it seems on boarder-line for the compromise in the corner.
I like visual image in the FCT-100. Bright crisp image of the Mars is always fine. and dark site nebula also looks pretty.