Dob Owner Shifting to GEM for Astrophotog.

[RogerOfHeaton]

Hi folks,

I currently run a 10inch Skywatcher Dob with equatorial platform and DSC encoders for Sky Safari Pro app navigation. Mainly viewing, although have begun DSLR prime focus solar/lunar work, and also use a Phil Dyer colour cctv camera for lunar vids. Loving it but of course, now realising that to learn more on astrophotog, in particular DSOs,I need to augment with a stable GEM mount.

Looked at HEQ5 Pro Synscan and Advanced VX, and have sort of set my eyes on the Advanced VX, for reasons of ASPA and later, StarSense.

Struggling with OTA decision....same old, same old frac or newt?

ED80 APO fits the bill for high FOV for DSOs at £430ish at F7.5 (reducer/flattener will bring it down to F6.3ish) but that 150mm Newt on the VX for something like £83 extra seems an incredible bargain. It does have a poor focuser, compared to say the Skywatcher 150 PDS (£228) but both are F5.

Since I'll be a newb with polar aligning and equatorials, my head says frac ED80, my heart says Skywatcher 150PDS. I know you get what you pay for but I'm a sucker for diffraction spikes.

Apologies for asking this but what do folks think please? Head and heart views much appreciated.

Cheers and thanks for any feedback.

[nmoushon]

For beginners I always suggest a frac just because its that much easier to use. No collimation worries. No need to upgrade the focuser. Shorter FL means you get to do longer suba without the need of guiding.

Though for a frac I would suggest not getting the native F7/5 scopes. They are just too slow in my book, even with a reducer. I would look for one in the F6-6.5 range. There are several brands out there that have doublet APOs in this range. my ED80 SW Equinox is native F/6.25 for example. So with my .76x reducer I get F/4.75, which is pushing it for a doublet but some how it works for me .

[DaveS]

Agreed. A shortish, reletivly fast semi-apo 'frac on a HEQ5 is hard to beat for the money, and it will run EQMOD from your laptop.

[m37]

If you really want diffraction spikes you can fake them on a frac with a home made mask using two bits of fishing line or thin wire in a crossed hair arrangement.

Some disapprove of this but hey, whatever floats your boat!!!

Or get an azeq6 and mount your dob's tube

[Herbig]

I'd recommend a William Optics Zenithstar 66 f5.9, they sell second hand for about £170 for a good one.