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GSO Low Profile 2-Speed Focuser with Rigel Systems N-Focus Electronic Focusing


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This is a " bad news / good news " review in high contrast.

I have a 10", f 4.7 Newtonian I custom built for astrophotography with the primary mirror pushed forward 2 inches to give more in-focus. Most of my observing is either by webcam, Mallincam, or DSLR.For this reason I chose a GSO low profile Crayford focuser. Since I focus through the camera I wanted to motorize the focuser I went to Rigel Systems for an adaptor system.

The GSO Crayford looks good out of the box but first thing turning the knog there were loud clicks and what felt like grinding. The unit was assembled completely dry. After a complete tear down and greasing it was moving properly.

Mounting was no problem since I was not replacing an existing unit but I found that the base plate was for an 8" to 10" - tube - not telescope. My tube is 12". Again, not a major difficulty, just annoying.

O.K. everything's mounted and adjusted. Try it with an Series 5000 EP movement is smooth throughout with no image shift. Fine focus is very nice.

Switched to a webcam with a 2" extension and then the Mallincam. Both exhibit image shift in the upper 1/2 of drawtube travel - a big problem when focusing on a 1/4" or 1/2" CCD with a 2x or 3x Barlow!

I then mounted up the Fuji DSLR, 1.8 lbs. The focus tube wouldn't lift. I start adjusting the tension plate a 1/2 turn at a time. About the third adjustment I hear a "tink" and the tube and camera drop. The tension plate snapped.

It turns out that while all other parts of the focuser are either aluminum or steel this plate is made of high zinc, cast pot metal and is very brittle. The focuser was, of course, 45 days old and out of warranty.

So I called the dealer. " There are no replacement parts available. GSO does not ship them to the US. You will have to buy a new focuser." I machined a new plate from aircraft aluminum - it won't snap again. I will not buy a GSO product again either. Lookout Moonlite - here I come.

Now the good news.

As I finished struggeling with the Crayford my new N-Focus arrived. When I ordered it from Leon at Rigel Systems ( www.rigelsys.com ) he didn.t have an adaptor for the Low-Profile GSO so he made one. The motor and adaptor are easy to install and the converted back to manual by simply loosening a thumbscrew.

The heart of the system is a battery powered electronic controller. This 2 button module supplied 12dc to the motor that is adjustable in both pulse with and interval. The result is an infinately variable variable slow speed that can be set up to emulate a stepper motor - changing focus in discrete, repeatable steps. Power is always at 12v elimating stiction and electronic braking stops movement instantly - no over-running. Simply pressing the second buttion gives you high speed.

I have used an older model JMI Motofocus om a Konsky 200 R&P focuser. It worked quite well but when pressing the button the focuser would move at slow speed (slowwwww speed) for a time and then automaticly switch to high. I would often find myself pressing the button repeated to avoid jumping to high speed. When heavily loaded the motor would struggle, and sometimes fail to start moving. Both of these annoyances are eliminated by the N-Focus controller.

The N-Focus controller will work with most other focus motors on the market so it can be retrofitted.

GSO, with no repair or parts available, is an example of poor customer service. I recently bought a laser collimator from ORION that was way out of alignment. They were willing to replace it ifI paid two more shipping charges (exceeding the cost of the instrument) but with no assurance that the new one would be properly aligned. The TeK's solution - buy a more expensive laser!

Bad customer service and relations. I won't be buying from them either.

As for Leon, owner of Rigel Systems..... As I said previously, he built an adaptor for use on a new style focuser to start with. Several weeks ago while juggling hand units ( focuser, autostar, pulseguide and camera) I dropped the controller. One of the buttons snapped off when it bounced. The unit was 4 months old so I sent it in for repair. Two weeks later I'm back in business. Cost - $00.00. He answers telephone calls and emails too.

THAT is customer service and good customer service. I highly recommend Rigel Systems products ad will continue to do business with him in the future.




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