electric focuser Vs Microfocuser
Posted 15 October 2005 - 02:11 PM
Posted 15 October 2005 - 07:55 PM
Here's what I settled on after trying the JMI Moto-Focus, which replaces the stock Celectron knob. I didn't like it; it was prone to overrun - not JMI's fault, just the design.
I then tried the WO Crayford manual, which was great, but at high powers, touching it caused the scope to vibrate.
So I now have the JMI NGF-S (since superceded), and it's just right; it's especially useful for imaging. Rough focus is handled by the stock focuser with a large rubber doughnut on it; fine focus belongs to the JMI.
Posted 16 October 2005 - 04:52 AM
I opted last year for the NGF-C from JMI. It works very smooth and I don't have any mirror shift anymore. Since I recently started with astrophotography and because there were some vibrations when touching the focuser at high power, I upgrade the NGF-C with the motofocus system. It is a real improvement as well. One of the advantages of the JMI focusers, in my opinion, is that you can upgrade the system when budget allows.
Posted 16 October 2005 - 05:03 AM
Posted 16 October 2005 - 09:47 AM
The JMI is like a snow blower for me. It's one of those things that I didn't realise how much easier it makes life, until you have one. I would recommend it without reservations.
As a side note, WO is apparently going to release a 2 speed version of their focuser at a fairly low introductory price point. If you're in no hurry, you may want to wait for this to come out.
Here is the link to my mini review of the NGF-C: JMI mini review
Posted 16 October 2005 - 10:55 AM
Posted 16 October 2005 - 03:43 PM
How is the JMI focus when you dont have motofocus? I have my Takahashi and the focus is a dream. How about JMI?
Very smooth, I was out imaging Friday night and the allen screw on the gear loosened, I couldn't find the allen wrench for it at the time so I just focused manually. With a very gental touch, I was able to achive focus without jarring the image on the screen.
Posted 17 October 2005 - 02:49 AM
Posted 17 October 2005 - 10:14 AM
Posted 17 October 2005 - 12:03 PM
I fully agree. It all depends what you want to do. The advantage with the JMI is that you can upgrade the focuser later if you intend to do astrophotography. On the other hand, if you just intend to observe visually a two speed might be handy as well (not a must though). I think WO is bringing a 2-speed on the market for their refractors, but I am not sure for the SCT's.
For visual either, although the JMI is more compact but with a more limited focusing range. For imaging, the JMI with motorfocus.
Posted 17 October 2005 - 12:55 PM
Posted 17 October 2005 - 11:45 PM
Get both, and do a shoot out article.
Posted 18 October 2005 - 03:15 AM
Good luck with your choice,
Posted 26 October 2005 - 10:00 AM