How would this work?

[Philip Benson]

After a number of years imaging DSOs I have recently taken a change of direction towards planetary.    My main imaging scope now is a TMB152/F8 triplet apo and following advice I went for a DMK 21AU618 mono camera for its small chip size and faster frame rate.  I have been experimenting on Jupiter over the last few weeks and found that the disk size was still quite small despite the small size of the chip.  So I got a 1.8x TMB Barlow 2nd hand.    That puts the F ratio up to 14.4.

After reading through some articles on planetary imaging it seems I should be aiming at  an F ratio between 15 and 30.   A Televe 4x Powermate would put me at the top end of that but I'm not sure how they would work with my scope.  So any advice would be appreciated.

[michael.h.f.wilkinson]

Personally I tend to image Jupiter between F/20 and F/25, depending on conditions. The Bresser 3x SA Barlow (really a telecentric, just like the powermate, rather than a barlow), which is the same as my Meade 3x TeleXtender should hit F/24 nicely, and the 2.5x powermate gets a very useful F/20 on your system. They should get near optimal match between pixel size and Airy disk. F/30 works nicely on Mars, because it is brighter, but on Jupiter the signal becomes a bit faint, so exposure times get a bit longer (and frame rates lower) than is desirable

[michael.h.f.wilkinson]

BTW, I moved this to the planetary imaging rather than observing forum, as it will attract more of the usual suspects