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Barry

Mak 150 Help for Planetary Imaging

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Hi

Can anyone help me with my proposed setup for planetary imaging?

I have bought a used Mak150 and plan to use the following ...

Mak, SCT Adapter(came with scope), SW SCT focuser (yet to buy). TV 3x Barlow, flip mirror, ASI120MC

Will this work or is it too long? If so what should I take out.

Thanks for your help.

Barry

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ASI 120 has small pixels so a 3X Barlow giving f/36 is way to much. You should pick a 2x Barlow that has unscrewable lens in 1,25" format (so that it can also be screwed to nosepiece for ~1.5x) like GSO/Revelation 2x Barlow. With that you can use it as 1.5x if the seeing is good and not best, and as 2x if the conditions are excellent (and no Barlow if poor). The SW SCT focuser is good if you give it SW motofocuser kit.

You can also think about getting yellow filter for limiting atmospheric dispersion on Saturn and other low alt. objects. It's cheap but not perfect. There are correctors (ADC), but they cost as much as new ASI120 ;)

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agreed, the seeing conditions pretty much dictate whether a barlow can be used or not. the mak150 will give some fine images of the moon and the planets. when you take it outdoors it will need a while to cool to the ambient temperature though.

as for the ASI120MC there some excellent images on here already.

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Siebert optics make Telecentric Barlows at a range of multiplication factors. These are like PowerMates, and better for planetary imaging. I am thinking of getting a 1.5x and 1.75x to be able to tune magnification better.

http://www.siebertoptics.com/SiebertOptics-barlows.html#Ad%202

At the top of this rather garish page there is an option to "Place an online order" (in red). Haven't tried it yet, but may do so later

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Have a go with just the scope and focuser and flip mirror to start with, and see what results you get with that. Then when you've worked it all out, add a 2x barlow/powermate.

James

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Hi there sounds a good set up ,but you may struggle with a x3 you might need a ext tube I would try a x2 Barlow or get the use of one I have a x3 Tal Barlow which is great but never really used it ,I have a C 9.25 and nevertheless use the x3. Good luck and post ya images as and when you get them ( with this thick white cloud no time soon)

Pat

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Thanks for all the replies... it seems that the x3 is out, then.

I think that I will use just the scope, focuser and flip mirror, see how that is then have a go with a x2.  I would like a reasonable image size but not at the expense of resolution.  I don't think that my standard SW x2 will be much good though so will have to find a better one. Any recommendations?

I will get a SW autofocus though, I have one on another scope and it really helps.

Barry

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SkyWatcher 2x Barlows aren't bad.  If you want other one - get one with detachable 1,25" lens to get smaller multiplications if needed (Baader Q-Barlow, GSO/Revelation 2x and other alike) - more flexible.

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