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Takahashi FSQ-106ED - robofocus or FLI ATLAS

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#1 Peter J

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Posted 06 November 2013 - 03:14 PM

Hi All,

for some time I've an FSQ-106ED. In the near future I want to use a FLI PL or ML 16803 with a FLI Centerline filter wheel.

Unfortunately, I do not know which focuser fits best to this setup.
The robofocus or the FLI ATLAS?

In particular, I am concerned because of the maximum payload.

What would you recommend?
What are your experiences?


#2 tomcody



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Posted 06 November 2013 - 04:44 PM

See this thread:
web page
and for all that weight you need an Atlas with a custom solid attachment to the scope see:
web page
P.S. with about 17 lb of camera/filter wheel/filters and focuser, you might even consider solid mounting the camera and letting the scope hang loose on the end of the focuser instead of the traditional: other way around! The scope should be the lightest part of the system you propose using.
One more thing, there is a lot of information on this kind of setup on the Yahoo group "narrowband imaging" as a lot of the members of that forum use similar setups.

#3 rainycityastro



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Posted 06 November 2013 - 04:52 PM

I've struggled quite a bit with slippage with the robofocus motor and lost data in the past.
I now use a robofocus successfully with the FSQ ED but the FLI is likely to be a better solution due to its absolute positioning.
Rigidity might also be a benefit that comes with the Atlas.

But then Robofocus is much cheaper and I just need one controller for all my scopes.

#4 mikeschuster


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Posted 06 November 2013 - 10:58 PM

+1 Atlas with fixed adapters.



#5 andysea



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Posted 07 November 2013 - 03:11 AM

The FLI is probably the golden standard.
However for my FSQ106EDX3 I got a controller+stepper motor caller usb-focus from a guy who makes them in france. http://www.usb-foc.us
I had a custom coupler made here in the US for $16 shipped and the entire setup cost me less than the robofocus controller alone. The motors are 4000 steps per revolution, which is more steps than the RF. Also the controller has a temp probe that is external and accurate to 0.1C.
It is not a closed loop system but so far, after almost one year of use, the motor has never missed a step therefore making the focuser positioning extremely repeatable and accurate. The custom coupler has never slipped once.
I get extremely sharp focus at f5 and f3.6.
I never lost any data.
That is my experience.


#6 Peter J

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Posted 27 December 2013 - 07:12 AM

Thanks to all for your advice. Very interesting information for me.

I'm still very interested to use the FLI Atlas, because of his technology. Therefore after long considerations currently I will go this way:

1. Step
- I will buy the FLI ML 16803 and the FLI Centerline filter wheel
- and manually focusing with the Takahashi focuser to get familiar with the new equipment and to find out the maybe existing flexure in the image train

2. Step
- Attaching additional weight on the image train so that the weight of the FLI Atlas is represented to find out whether this additional weight produces flexure in the image train

3. Step
- Depending on the result in step 2 buy the FLI Atlas or another focuser like Robofocus or USB_Focus

I will inform you as soon as I have the first results.

Clear Skies

#7 SAP Astro

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Posted 24 January 2014 - 03:22 AM


I am also facing this dilemma... which automatic motorized focuser to buy for my FSQ 106 ED. While I was surfing the net, I came across the JMI Motofocus and SmartFocus combination. Has anyone used it. This option seems to be entirely ignored in the above discussion. Is it because the general user experience with the above product is bad?

Thanks in advance,


#8 Wmacky



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Posted 24 January 2014 - 01:56 PM

I just went with the Rigel stepper system due to the nice pricing, and the fact he has, or can make an adapter for almost any scope. Here'e the bonus: The stepper is on it's own bracket, and quickly mounts to a bracket thats left on the focuser. The owner just informed me that the stepper-bracket-gear combo is the same for every setup. You only have to but the mating bracket, and mating gear for your specific focuser. In other words, to motorize all your scopes, you can buy just one removable stepper unit, and a bunch of various brackets / gears for you scopes. Huge savings!

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