ZWO EAF on SW Explorer 150p (not PDS)?

[skipgazer]

Hello everyone. Bit of a niche request for my first post, but is anyone using the ZWO EAF focuser on the standard Crayford type 150/750 Sky-Watcher Newtonian? The focuser is stated as being compatible only with Sky-Watcher's astrophotography OTAs with their dual-speed focuser, but I can't see why that is except perhaps that ZWO assume you wouldn't do imaging with the standard tube - whereas it works fine with my Nikon D750. I'm intending to get one but seeking reassurance it will work. I've seen this video: it's on a bigger OTA by the looks of it, but the focuser looks the same as mine (in French, but very clear even if you don't speak it): 

 

[Realtimedoctor]

I use the ZWO EAF on the standard single speed crayford focuser that came with my 200p.

Your scope will have the same focuser. Mounting with the orginal bracket is slight pain in Bottom! I use one of the small hex screws and screwed it on the focuser lock hole. Everything works perfectly. 

You may need to increase the tension on the focuser, otherwise the focuser slips significantly with heavy loads. 

 

Cheers, 

Nish

[skipgazer]

Thanks for that idea. Well, I've ordered one. Already increased tension, having initially tried Sky-Watcher's own focus motor. It worked well as a standalone but coupled with the HitecAstro DC controller I could not get it to work with Ekos - whereas I'm assured the ZWO one does work. 

[Realtimedoctor]

3 minutes ago, skipgazer said:

Thanks for that idea. Well, I've ordered one. Already increased tension, having initially tried Sky-Watcher's own focus motor. It worked well as a standalone but coupled with the HitecAstro DC controller I could not get it to work with Ekos - whereas I'm assured the ZWO one does work. 

I used to use the skywatcher dc motor as well before ZWO. However, I made my own motor controller, from the moonlite protocol with an arduino. Ekos used to run it fine, but sometimes took to much time to focus, due to the backlash. So needed some repeatability, hence upgraded to ZWO. 

[skipgazer]

Update in case anyone else is searching for the same topic. It does need a bit of juggling but it attaches OK and feels solid. The biggest issue is the way the ZWO bracket has two ridges on its underside, parallel to but also fairly close to its longitudinal centreline, which means you have to balance tightening the attachment bolts to level it against the surface of the focuser housing - which itself is slightly curved - because it can wobble from side to side. I acquired two 3mm x 16mm hex head bolts to attach it, and used one of the supplied M5 bolts as an additional anchor point in the hole where the (useless) Sky-Watcher focuser lock bolt normally goes, although that's not really necessary. Pic: 

[Peter Reader]

Hows the performance of this? I'm looking to get an auto focuser for my 200P but was concerned I needed the DS focuser to make it work...

[skipgazer]

I've had only two nights of clear skies to try it, while simultaneously learning KStars/Ekos, but certainly the focus motor works extremely well and seems solidly attached. Used 'manually', by which I mean not via software but with the optional plug-in hand controller, it's a dream compared with trying to do it by turning the focuser knobs by hand, with all the wobbling around of the OTA that entails.