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View Full Version here: : Imaging Mars with a 4" Refractor


Saturn488
22-09-2020, 06:05 PM
Has anyone had any luck imaging Mars with a small 4" refractor?

thinking 2x or 3x Barlow will help a lot, maybe even a 5x?

sunslayr
22-09-2020, 07:29 PM
Really depends on what you want to see, you might be able to make out the ice caps but I wouldn't count on seeing much else in terms of terrain details. Give it a go if that's all you have, you won't get a better chance at it for another 15 years.

Saturn488
22-09-2020, 07:42 PM
Yeah I have a 3x but might buy a 5x.

multiweb
22-09-2020, 07:45 PM
That's a big ask. I'm just south of 10" at ~7m FL and that's not a trivial exercise to get details. It's bright but tiny.

sunslayr
22-09-2020, 08:04 PM
Whats your focal length? You would probably want about f20, any more than that and it will be too dim. I might give it a go with my 4" tonight if I'm not too tired.

Saturn488
22-09-2020, 08:24 PM
Focal Length is 714

sunslayr
22-09-2020, 08:33 PM
In that case I wouldn't suggest you get a 5x, I'd stick with your 3x. Now If you were to buy a cheap newt on the other hand ...

Saturn488
22-09-2020, 08:34 PM
I was thinking that, but another telescope....

Need the bloody room haha.

Saturnine
22-09-2020, 09:30 PM
Hi Chrys

I can't give you first hand what 4" would achieve but I often use a 5" f7.5 refractor with an 3X barlow and get reasonable images from it. See my recent images posted in the Beginners Forum to give some idea of what small scopes can do.

dannat
07-10-2020, 12:36 PM
a couple of guys on CN have got some great results with their quester 3.5”, 1 only uses a 2x barlow, so it’s possible