Which scope for a focuser stepper motor?

[Benjamin]

I have a an 8" Newt with a TS-UNCN2 (or very similar) focuser, an ED100 with the Skywatcher dual speed 10:1 focuser, and an ED80 with a single speed Skywatcher focuser. All can have a Rigel Stepper motor added to them but I can really only afford to add a motor to one or maybe two of them. Which one (or two) to choose? They all sit atop an HEQ5 Pro and eventually will have a CMOS camera and filter wheel attached. Upgrading the focusers on the ED scopes would be spending too much I think (and they haven't been a problem), but do wonder if adding a stepper motor to the Skywatcher focusers might be a bit of a waste or whether, conversely, this might improve the focusers to some degree?

Any advice appreciated.

[NorthernLight]

Hi Ben, all things equal I'd add it toothed scope with the longest focal length as that demands the most from focusing. Your Newton is probably the choice here. I also find that my Newton vibrates more during focusing than my ED80, so would benefit even more from an electric focuser.

Cheers,

[Benjamin]

Cheers Max. That what my inclination. It turns out the Rigel Stepper motor can be transferred between scopes so thinking of getting all 3 focusers setup with brackets etc. and transfer the motor and controller as required.

[Merlin66]

In my experience the faster f ratios require the "tightest" focus control.
I'd say the 10:1 focuser and the SW electronic motor has been mandatory on the solar scopes I use.......

[Astrofriend]

Hi,
Are you use your telescopes for visual or photographing?

If doing photo I will say there is a must to have a focus motor. Since I built my focus equipment I reach much better focus. And I also have found how temperture sensitive it is. I have it temperature regulated and it works.

Here is my little focus projekt:
http://astrofriend.eu/astronomy/projects/project-motor-focus/project-motor-focus.html

When I bought it it cost abot 160 Euro, I have the middle motor. It's more expensive today.

A lot of people built their own controller and maybe can save money. Stepper motors are cheap at Ebay.

Lars

[Benjamin]

Hi Lars, it's just for photography and will interface with SGP (which I'm currently learning). Visually I like manually focusing as the slight movement generally helps detecting faint fuzzies :-) Ended up getting a single Rigel motor and nSTEP controller that can be moved across all the scopes I use for imaging. Can't wait for it all to turn up!

[Astrofriend]

Hi Ben,
That will be very practicle if you can move your motor focuser between your telescopes. Your astronomy season must go to theend now, will you have it up and run before? For us up here in north it just have been started to have dark nights.

I wish you good luck!

Lars

[Benjamin]

Hey Lars, not the end here in Brisbane although temperatures are already a bit crazy (already 31c). My DSLR sensor is not very going to like it very much but still lots of dark clear skies to be had all year (with luck). Hoping for the motors before the next new moon but really no idea when they might turn up (in the process of being made I believe). Have a Swedish friend I'm preparing some Kanelbullar for so I'd better get baking! :thumbsup:

[Astrofriend]

Hi Ben,
31 C, that was high, when we start here in August we have about 15 C degrees, but it's not dark enough then, better in middle of september and then it has cold down to about 5 to 10 C degrees. Not very big problem with the cameras at that temperature, even an uncoold DSLR works relative good, but even better at zero degrees of course.

The only thing I do in August is watching for the Perseids meteor shower. This how it could be when watching Perseids:
http://astrofriend.eu/astronomy/my-astronomy-photo/meteor-shower/perseids-2015.html

There is an Timo who writes at the Swedish forums that he go to Australia sometimes. We all like kanelbullar :-)

/Lars