Scopes for Planetary Imaging

[Gina]

I'm thinking of trying planetary imaging in the future particularly Jupiter and Saturn.  I have a suitable camera (or two) with an ASI1600MM-cool and an ASI185MC.  Much the same pixel size but one is colour so resolution sacrificed for colour.  I have an MN190 Mak-Newt with 1000mm focal length and 190mm mirror so f5.3.  I could use this with a Barlow.  As an alternative I'm wondering if some other scope would be better.

[GuLinux]

I would stay on the mak-newton, or at least try it before thinking of buying anything else.

Experiment a bit on the moon: it's always there (well, pretty much... weather might be a problem).

You might need a barlow, just be careful to not under/over sample, a mistake I did a lot in the past: your telescope resolution power is roughtly 0.63 arcseconds.

With your camera pixel size, you get 0.78. You should reach a resolution power lower than a half of your telescope, so a 3x barlow would probably be the best choice. 2x will get you a little undersampling, while a 5x will defintely oversample.

[Freddie]

You may also want to have a look at where Jup and Sat are over the next few years before spending any money on this. They are not well placed.

[Gina]

Thanks for the replies   Sorry for not acknowledging them before but the thread was moved and I've only just found it.

I have 2x and 3x Barlows so that's alright.  Yes, I know Jupiter and Saturn will be pretty low over the next few years and I'm not saying I will definitely be trying to image these any time soon - just thinking of possibilities

[Stub Mandrel]

Skywatcher 150PL is 1200mm and pretty affordable

[Gina]

But only slightly longer FL than my MN190.

The nearest telescope I can find to the MN190 plus 3x Barlow is the Skywatcher Skymax 180 PRO.  Slightly lower focal length but same focal ratio.  Would this be optically better than NM190 plus 3x Barlow?

[nucdoc]

This is my best shot of jupiter using ZWO 120 mono with LRGB and 60 second exposures

I have not yet mastered winjupos

f/15 

 

http://astrob.in/full/242616/0/

[nucdoc]

4 hours ago, nucdoc said:

This is my best shot of jupiter using ZWO 120 mono with LRGB and 60 second exposures

I have not yet mastered winjupos

f/15 , Q7

 

http://astrob.in/full/242616/0/

Sorry, meant to put this in your post about using RGB imaging for planets, but was working off my iPhone and posted it to the wrong thread.  I find that after 90 seconds it is hard to keep the details from blurring if you are shooting all 4 LRBG, so I stick with only 60 seconds for each

[Owmuchonomy]

Hi Gina a good rule is to aim for f/ of around 5x your pixel size. So with the ASI 185 you need to be near f/ 20. Your 3x gets close. For example with my ASI 174 I use my SCT at f/ 25 or my Lunt 60 at f/ 20. As pointed out the best targets are moving away from ideal positions so the ADC I mentioned in another post may help.