Imaging Mars with a 4" Refractor

[Saturn488]

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 (David)]

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]

Yeah I have a 3x but might buy a 5x.

[multiweb (Marc)]

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 (David)]

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]

Originally Posted by sunslayr

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.

Focal Length is 714

[sunslayr (David)]

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]

Originally Posted by sunslayr

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 ...

I was thinking that, but another telescope....

Need the bloody room haha.

[Saturnine (Jeff)]

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 (Daniel)]

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