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I’ve found it’s impossible to focus near the zenith without fully locking down the focuser first. Without locking it down the focuser slips almost immediately so you can’t first focus and then lock it down. You can actually visually see it slipping when the lock mechanism is undone. 
 

Attached  to the scope is an asi 6200mm and 7x2” filter wheel so about 3kg. Not the lightest but by no means should it be near the limitations of the focuser. 
 

Is this normal or is it possible to tighten the focus mechanism ? 
 

Anyone else using this scope ? Do you first lock the focuser before focusing ? 
 

Thanks ken 

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I get the same problem with the focuser on my Esprit 150, and on the later models like mine they replaced the variable tension knob with a simple locking leaver. 

John 

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Just found this info on CN - might be useful?

To adjust it properly, you must first remove the cover from the rack and pinion. by unscrewing the small flat chrome screw on the bottom of the focuser (use a bent paper clip in the shape of a U or a pair of sharp tipped tweezers as a spanner wrench to loosen that chrome screw. Then remove the cover over the rack gears and LOOSEN the two screws that tighten the tension clearance on the gears ( you will need a small #3 Phillips head screw driver, get the clearance loose and sloppy, but still able to turn the focuser knobs and move the focuser in and out.

(WHY? The three screws along the top of the focuser adjust the play in the focuser tube by pressing the tube against the bottom of the focuser housing, if you do not loosen the pinion gear shaft, you are just pressing the focuser tube against the pinion gear, not the bottom of the focuser housing).

NOW adjust the three small allen hex screws along the top of the focuser (use a tiny drop of acetone to loosen the glue holding them) they take a 1.5mm allen wrench. Adjust the three screws while turning the focuser knob in and out until all slop in the focuser tube is removed and the tube still slides in and out without binding. (Start with the middle screw, then the front screw, then back screw).
Now go back and tighten the two phillips screws on the rack until you do not feel any slop when reversing direction of the focuser knob AND the rack moves smoothly without binding, (DO not over tighten this adjustment as it will cause rough movement and binding of the gears, also slop will only be felt as looseness or back lash in the gears and not hurt the scope movement, so a little loose is beter than too tight).
Replace the cover and screw and you are done.

EDIT: A few more points, the glue used to secure the three screws along the top of the focuser will re-dry in about an hour (if you don't use too much acetone to loosen them, if the stay loose? just use a drop of clear nail polish to re-secure them.
Let me know how this works for you? :jump:
Rex
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This is a known problem with the Takahashi focusers and isn't unique to the 106. My FSQ-85 and TSA-120 had this problem too.  The optics are fantastic on these scopes but unfortunately they kind of fall down on the focuser. As Bill posted there are work arounds. And he came up with one. For me, I always replace my Tak stock focuser with a Feather Touch if I am using it for imaging as I have had this problem in the past. Not a inexpensive option but it, or the Moonlight, are better options overall than the stock Tak focusers and unfortunately AP is never cheap or easy... 

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It’s come full circle ☹️

I got back from holiday in Germany expecting to work hard at resolving remaining tilt issues etc.  But I discovered the focuser is still slipping even with the motor focuser attached. 😬

The auto focuser (sesto senso) was at position 5940 on Friday evening focused on R. Last night it was at position 3120 focused on the same filter. 

The focuser has been adjusted and I’ve been told not to tighten it any further or this will introduce tilt.
 

@Skipper Billy how tight do you have the  focuser clamp Locked ? I’m a bit reluctant to tighten this any further as I believe it may well be causing some form of tilt. 

Note- the camera and filter wheel is only 2.2kg so shouldn’t really be a big load for this setup ???

ken 

 

A990501C-EF22-4BF3-864F-4CDA5BED3011.jpeg

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1 hour ago, Ken82 said:

@Skipper Billy how tight do you have the  focuser clamp Locked ? I’m a bit reluctant to tighten this any further as I believe it may well be causing some form of tilt. 

Hi Ken

Your scope is one that just keeps on giving !!! 😬

I dont use the Sesto Senso I use a Lakeside which attaches in a completely different way.

I cant really see how tightening the focuser clamp can introduce tilt??

It doesnt help you but the Lakeside has never slipped even with an Atik 16200, EFW3 and a full set of 2" filters handing off it.

Good luck my friend!

 

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33 minutes ago, Skipper Billy said:

Hi Ken

Your scope is one that just keeps on giving !!! 😬

I dont use the Sesto Senso I use a Lakeside which attaches in a completely different way.

I cant really see how tightening the focuser clamp can introduce tilt??

It doesnt help you but the Lakeside has never slipped even with an Atik 16200, EFW3 and a full set of 2" filters handing off it.

Good luck my friend!

 

Yea thanks I think I’m due a bit of luck by now 😩
 

So you don’t tighten the locking lever at all ? What’s the weight of your camera etc ? 
 

I must say the focuser feels particularly poor certainly in comparison to my FSQ85 which holds this camera etc without any additional tension. I just wish my 85 had a larger corrected field. Where my 85 fails the 106 appears to excel! 
 

I’m not sure I shared this video but this was the focuser in the beginning ☹️

 

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22 minutes ago, Ken82 said:

So you don’t tighten the locking lever at all ? What’s the weight of your camera etc ? 

My focus locking screw is always slack - otherwise the focuser wouldn't be able to move the focuser.

My camera, filter wheel assy. is 2.5kgs / 5.5 lbs.

Is that video taken with the Sesto attached??

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On 07/04/2020 at 03:05, Dr Strange said:

This is a known problem with the Takahashi focusers and isn't unique to the 106. My FSQ-85 and TSA-120 had this problem too.  The optics are fantastic on these scopes but unfortunately they kind of fall down on the focuser. As Bill posted there are work arounds. And he came up with one. For me, I always replace my Tak stock focuser with a Feather Touch if I am using it for imaging as I have had this problem in the past. Not a inexpensive option but it, or the Moonlight, are better options overall than the stock Tak focusers and unfortunately AP is never cheap or easy... 

I would far rather use the Tak focuser than the Moonlite which I think is a poor choice for holding a heavy camera and filterwheel but the FT is superb.

Olly

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2 hours ago, Skipper Billy said:

My focus locking screw is always slack - otherwise the focuser wouldn't be able to move the focuser.

My camera, filter wheel assy. is 2.5kgs / 5.5 lbs.

Is that video taken with the Sesto attached??

No the sesto wasn’t connected in this video. The focuser does stop it dropping but clearly during the night it still slips incrementally without locking it down completely. 
 

1 hour ago, ollypenrice said:

I would far rather use the Tak focuser than the Moonlite which I think is a poor choice for holding a heavy camera and filterwheel but the FT is superb.

Olly

I would normally be happy to spend an extra 1k on the FT focuser.  But I’m reluctant to do that because when i compare raw unaligned RGB images that yourself, skipper billy and 4 others have kindly supplied, my focal lengths (for RGB) in comparison are much further apart.  

I mean what am I supposed to do now ☹️

 

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14 hours ago, Ken82 said:

No the sesto wasn’t connected in this video. The focuser does stop it dropping but clearly during the night it still slips incrementally without locking it down completely. 
 

I would normally be happy to spend an extra 1k on the FT focuser.  But I’m reluctant to do that because when i compare raw unaligned RGB images that yourself, skipper billy and 4 others have kindly supplied, my focal lengths (for RGB) in comparison are much further apart.  

I mean what am I supposed to do now ☹️

 

Refund?

Olly

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On 07/09/2020 at 07:29, ollypenrice said:

Refund?

Olly

Yes you could be right. I didn’t want to give up on a good optical test but I’ve been trying hard to resolve this and it just  feels endless at the moment. 

I contacted primalucelab in the hope that I could increase current or change settings to better lift/hold the camera but they said if my settings are already “heavy load” then the limit is the focuser itself. It doesn’t surprise me seeing how loose it was without the auto focuser. 

Ian is on holiday now for a week so I’ll see What he can add but just a little disappointed. 
 

Ken 
 

Edit - I should add the focuser isn’t mega loose, it would certainly be fine for a dslr or a light camera. Or indeed if you focus and then lock it I think that would be ok ?? But using a auto focuser to automate the process it’s not usable at this moment. 

Edited by Ken82

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