[Fox]

Dear Planetary image experts:

Well, I’ve decided to have go at planetary imaging. As someone who has NO experience in AP at all, I seek your expertise as a newbie, and have some questions I hope you can advise me on. As you can see from my signature, I have a Televue NP127is (f/5.2) as my main scope, and Meade LXD75 mount (yeah, the LXD75 isn’t so great, I know). I don't have a DSLR, although from what I can tell, the optimum equipment nowadays is via a dedicated planetary colour webcam (eg. ZWO series) and stack images. So, three questions to begin with:

1) Choice of webcam. I have my eye on the ZWO’s, either:
(i) ASI 120MC (about $220)
(ii) ASI 120MC-S (usb 3.0) (about $320)
(iii) ASI 224MC (usb 3.0) (about $420).

The 120MC seems ideal (up to 30 FPS) for the entry level newbie, and only $220. On the other hand, the 120MC-S for only $100 extra allows USB 3.0 for faster data transfer and up to say 60 FPS, thus potentially giving better resolution. As a third option, for an extra $200, the 224MC has this ‘low noise’ ability, allowing extensive short exposure stacking for more potential for deep sky images via a webcam. I am leaning towards to 120MC-S (for $320), but is the 224MC better in the long run ? ie. more multipurpose potential just in case I get the AP bug and would like to have a go at deep sky down the track...

2) From what I understand, with the NP127is, the optimum focal ratio should be around f/20. I therefore need say a 4x barlow to get this. Should I get the TV 4x Powermate ($490) to give f/21, or would a good 5x barlow (a lot cheaper than a Powermate) (ie. f/26) be “close enough” and quite acceptable ?

3) I don’t have a PC laptop at all (always been an Apple desktop owner). I’m quite happy to get a basic PC laptop with USB 3.0 for out in the field data acquisition for the webcam. I figure I can just transfer to my iMac and then use PC emulation from thereon to do the stacking, image manipulation etc. Is a PC laptop the most sensible way to go ?

I guess that’ll do for now in terms of just getting the equipment right. Am I on the right track at all...? All advice is welcome...

Cheers
Fox