ZWO EAF on Takahashi TOA-150? ZWO EAF · N Foldager · ... · 25 · 646 · 6

nfol 0.00
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Does anyone have experience fitting a ZWO electric auto focuser to a Takahashi TOA-150? 

ZWO tells me that it will not fit.

But maybe it is possible after some modification and/or with a custom made bracket?

Best regards,
Niels
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Field_sweeper 0.00
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I feel like as long as the stepper motor/couplers can mount to the removed knob of the focuser on that scope, it should be fine... Obv the bracket matters, but what does the underside of that focuser look like? Does it have screws or a large center screw hole?  You can take out 2 screws, and replace with longer ones to accommodate the focuser bracket. I did that on my scope (not that same one) Worst case, a custom bracket. IF the couplers don't fit and the shaft of the focuser knob is too big, THAT too can be fixed with a coupler off amazon with the size of the EAF shaft and the tak shaft on the other side, and be fine. 

I am not sure why they think it wouldn't work? What did they say? You could ask for clarification.

The last post on this forum here  https://www.cloudynights.com/topic/834238-toa-150b-which-auto-focuser/

Shows it works just fine. So give it a shot.  About the only think I would worry about is the weight capacity of the stepper, I think it can do 11 lbs, so as long as the focuser tube with camera and other stuff is less than 11lbs, you should be fine. (keep in mind, that the max weight will be at zenith)

https://agenaastro.com/zwo-eaf-electronic-automatic-focuser-takahashi-bracket.html
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Vroobel
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Everything is possible with more or less of DIY. 😉
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JamesPeirce 2.11
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Does it have the 8mm shaft attachment point most of the other Takahashi focusers have? In which case, you can install the ZWO EAF using stock parts along with a suitable 5mm to 8mm coupling. Those can be purchased on Amazon and all are just products available from AliExpress, etc. with markup added. You can also easily get the coupling of the style ZWO includes.

I wrote a little thing about my FS-60 a while back and have since put them on other Takahashis like the Epsilon 180D.

https://www.cloudynights.com/topic/825048-attach-zwo-eaf-to-takahashi-fs-60cbq-fc-76dcu-etc/

ZWO sells an accessory pack for Takahashi and other telescopes that includes an alternative mounting rail. But the bar-shaped one that comes with the EAF ought to have plenty of clearance on that refractor.

One thing that strikes me is that you may want to get a compression fit coupling instead of one which bites into the shaft, depending on how heavy the optical train will be. But I haven’t had issues with an APS-C camera, filter wheel, etc.

IMG_1340.jpeg
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nfol 0.00
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Thank you very much for your answers. I'll go for it and see what happens.

I wonder if it would be a good idea to couple the EAF to the fine adjustment shaft?   Then I would get finer regulation and lower leverage for heavy stuff. 

Best regards,
Niels
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Habib_Sekha 1.51
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I use a ZWO EAF on a TOA130-NFB, ZWO sells a sepecial part for attachment on the TOA. However, I do not know if it is suitable for the 150.

EDIT:

This site mentions the suitability of the ZWO part for the 150B

“This bracket allows you to easily connect the ZWO EAF electronic focuser to Takahashi TOA-130NFB, TOA-150BFSQ85 & FSQ106”


https://www.testar.com.au/products/zwo-eaf-bracket-for-takahashi
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Field_sweeper 0.00
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N Foldager:
Thank you very much for your answers. I'll go for it and see what happens.

I wonder if it would be a good idea to couple the EAF to the fine adjustment shaft?   Then I would get finer regulation and lower leverage for heavy stuff. 

Best regards,
Niels

Absolutely not.  ONLY couple it to the course knob, there is no benefit to using the fine one, and you risk damage. Just use the course side.  The stepper moves plenty fine to get even more accurate that you ever would.  That is how everyone mounts them.
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Supro 4.37
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My TOA-130 has the EAF using the bracket from ZWO. It's never had any troubles, and works well (on the coarse knob)

It's the 4inch focuser. I'm pretty sure that's the same as the 150?
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nfol 0.00
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@Nick Grundy

According to ZWO, their EAF fits the TOA-130 but not the TOA-150.
I have asked them to explain it in more detail, but have not received an answer.
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aabosarah 9.31
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James Peirce:
Does it have the 8mm shaft attachment point most of the other Takahashi focusers have? In which case, you can install the ZWO EAF using stock parts along with a suitable 5mm to 8mm coupling. Those can be purchased on Amazon and all are just products available from AliExpress, etc. with markup added. You can also easily get the coupling of the style ZWO includes.

I wrote a little thing about my FS-60 a while back and have since put them on other Takahashis like the Epsilon 180D.

https://www.cloudynights.com/topic/825048-attach-zwo-eaf-to-takahashi-fs-60cbq-fc-76dcu-etc/

ZWO sells an accessory pack for Takahashi and other telescopes that includes an alternative mounting rail. But the bar-shaped one that comes with the EAF ought to have plenty of clearance on that refractor.

One thing that strikes me is that you may want to get a compression fit coupling instead of one which bites into the shaft, depending on how heavy the optical train will be. But I haven’t had issues with an APS-C camera, filter wheel, etc.

IMG_1340.jpeg

Excellent post. You are one of the few Epsilon owners here that I didn't see using an Optec Leo Focuser. I actually have a leo focuser myself, but frankly I would just prefer to use the EAF if that works. I like to use an OAG and it might be difficult to do with the native corrector and the Leo focuser. Have you noticed any issues with it in terms of tilt or focus drift?
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Supro 4.37
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Ashraf AbuSara:
tilt or focus drift?


If I remember correctly, the EAF on the stock focuser was ok (no focus drift), but there was definitely the light leak. (tested with a flashlight doing darks). I think you can print a bracket though from thingiverse or printables
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JamesPeirce 2.11
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Ashraf AbuSara:
James Peirce:
Does it have the 8mm shaft attachment point most of the other Takahashi focusers have? In which case, you can install the ZWO EAF using stock parts along with a suitable 5mm to 8mm coupling. Those can be purchased on Amazon and all are just products available from AliExpress, etc. with markup added. You can also easily get the coupling of the style ZWO includes.

I wrote a little thing about my FS-60 a while back and have since put them on other Takahashis like the Epsilon 180D.

https://www.cloudynights.com/topic/825048-attach-zwo-eaf-to-takahashi-fs-60cbq-fc-76dcu-etc/

ZWO sells an accessory pack for Takahashi and other telescopes that includes an alternative mounting rail. But the bar-shaped one that comes with the EAF ought to have plenty of clearance on that refractor.

One thing that strikes me is that you may want to get a compression fit coupling instead of one which bites into the shaft, depending on how heavy the optical train will be. But I haven’t had issues with an APS-C camera, filter wheel, etc.

IMG_1340.jpeg

Excellent post. You are one of the few Epsilon owners here that I didn't see using an Optec Leo Focuser. I actually have a leo focuser myself, but frankly I would just prefer to use the EAF if that works. I like to use an OAG and it might be difficult to do with the native corrector and the Leo focuser. Have you noticed any issues with it in terms of tilt or focus drift?

Thanks! Regarding the Optec Leo Focuser, I imagine I would use one if this was set up in an observatory. As it stands, I do all of my imaging on the road, so I like to keep things pretty simple and compact wherever I can. I have a couple cameras which are tilt adjusted and mount to my telescopes using the Baader QuickChanger system, which, while manual, gives me a point of rotation that does not tilt and serves me well enough. So it was reasonable to simply set the Takahashi CAA to my preferred orientation and leave it there.

Based on my limited experience with only two relatively young Epsilons, rotating the stock CAA does not introduce material tilt or collimation issues. I suspect part of this is that some people make changes and do not follow the full collimation routine for the telescope, which involves rotating the CAA, and collimates the telescope not just for one point of rotation but across the range of rotation. And because my cameras are individually tilt adjusted to the point of attachment, this also means I have not had to deal with mechanical tilt from the Takahashi focuser parts themselves. Maybe copy variation exists or perhaps there have been design improvements.

Focus drift has not been an issue for me using the ZWO EAF, nor with this focuser. I have the tension adjusted to a rather weak point so the EAF is probably taking on some tension to hold the focuser in place. I guess if I had a rather heavy optical train and it seemed to shift a bit, I might try tensioning the focuser a little bit more. But I haven’t had to solve that potential problem yet.

- - -

A couple addenda:

A new M4 bolt is needed and probably won’t match anything that comes with the ZWO EAF. Like the 8mm shaft, the relatively young Takahashis I have used all use that same M4 attachment under the focuser. I used my digital calipers to measure the length of the thread of the stock two-point head that comes with the stock focuser and added the depth of the mounting rail. Probably goes without saying that one can usually be purchased at a big box home improvement store or ground down from the odds and ends we all probably have. I have a multi-part kit of stainless steel socket head M[x] bolts I can just grab from.

The Takahashi and other telescopes accessory pack ZWO sells does come with a 5mm to 8mm coupler that works for these telescopes. Just feels like an unnecessarily expensive solution unless the alternative bracket is desired for some reason.

In my photo example I used a more rigid compression-fit coupling that is fatter. Works great, and I like it more than the style that comes with the EAF that bites the shaft with grub screws. Since it is less rigid, although still flexible, I set it up with more care to minimize flex, and I used a couple washers to space out the bracket that came with the EAF so it has enough clearance to spin without rubbing.
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JamesPeirce 2.11
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Nick Grundy:
Ashraf AbuSara:
tilt or focus drift?


If I remember correctly, the EAF on the stock focuser was ok (no focus drift), but there was definitely the light leak. (tested with a flashlight doing darks). I think you can print a bracket though from thingiverse or printables

What light leak? I am not sure I have encountered this. I imagine the only possible light leak is at the point of attachment, somehow leaking in alongside the M4 bolt to the plate Takahashi includes with these telescopes? If so, the introduction of some foam tape or a similar layer at that attachment point ought to do the trick without a need for external parts?
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Supro 4.37
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James Peirce:
What light leak?


on my Epsilon 160 stock focuser, there was a light leak. As far as I could tell, it was from the within the focuser tube. This is the attachment someone else pointed to. Apparently it fits just in front of the corrector? I printed one but didn't get it to fit perfect. I ended up getting the Leo anyways though so I stopped trying. 
image.png
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JamesPeirce 2.11
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Nick Grundy:
James Peirce:
What light leak?


on my Epsilon 160 stock focuser, there was a light leak. As far as I could tell, it was from the within the focuser tube. This is the attachment someone else pointed to. Apparently it fits just in front of the corrector? I printed one but didn't get it to fit perfect. I ended up getting the Leo anyways though so I stopped trying. 
image.png

Interesting. My first pass with my Epsilon 180D didn’t turn up an issue, but I’ll give it a stress test with a flashlight next time I’m out.
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Supro 4.37
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James Peirce:
my Epsilon 180D didn’t turn up an issue,


it might've been just the 160, but worth checking. I couldnt see it in my images though, just in darks and a bright light nearby
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aabosarah 9.31
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James Peirce:
Ashraf AbuSara:
James Peirce:
Does it have the 8mm shaft attachment point most of the other Takahashi focusers have? In which case, you can install the ZWO EAF using stock parts along with a suitable 5mm to 8mm coupling. Those can be purchased on Amazon and all are just products available from AliExpress, etc. with markup added. You can also easily get the coupling of the style ZWO includes.

I wrote a little thing about my FS-60 a while back and have since put them on other Takahashis like the Epsilon 180D.

https://www.cloudynights.com/topic/825048-attach-zwo-eaf-to-takahashi-fs-60cbq-fc-76dcu-etc/

ZWO sells an accessory pack for Takahashi and other telescopes that includes an alternative mounting rail. But the bar-shaped one that comes with the EAF ought to have plenty of clearance on that refractor.

One thing that strikes me is that you may want to get a compression fit coupling instead of one which bites into the shaft, depending on how heavy the optical train will be. But I haven’t had issues with an APS-C camera, filter wheel, etc.

IMG_1340.jpeg

Excellent post. You are one of the few Epsilon owners here that I didn't see using an Optec Leo Focuser. I actually have a leo focuser myself, but frankly I would just prefer to use the EAF if that works. I like to use an OAG and it might be difficult to do with the native corrector and the Leo focuser. Have you noticed any issues with it in terms of tilt or focus drift?

Thanks! Regarding the Optec Leo Focuser, I imagine I would use one if this was set up in an observatory. As it stands, I do all of my imaging on the road, so I like to keep things pretty simple and compact wherever I can. I have a couple cameras which are tilt adjusted and mount to my telescopes using the Baader QuickChanger system, which, while manual, gives me a point of rotation that does not tilt and serves me well enough. So it was reasonable to simply set the Takahashi CAA to my preferred orientation and leave it there.

Based on my limited experience with only two relatively young Epsilons, rotating the stock CAA does not introduce material tilt or collimation issues. I suspect part of this is that some people make changes and do not follow the full collimation routine for the telescope, which involves rotating the CAA, and collimates the telescope not just for one point of rotation but across the range of rotation. And because my cameras are individually tilt adjusted to the point of attachment, this also means I have not had to deal with mechanical tilt from the Takahashi focuser parts themselves. Maybe copy variation exists or perhaps there have been design improvements.

Focus drift has not been an issue for me using the ZWO EAF, nor with this focuser. I have the tension adjusted to a rather weak point so the EAF is probably taking on some tension to hold the focuser in place. I guess if I had a rather heavy optical train and it seemed to shift a bit, I might try tensioning the focuser a little bit more. But I haven’t had to solve that potential problem yet.

- - -

A couple addenda:

A new M4 bolt is needed and probably won’t match anything that comes with the ZWO EAF. Like the 8mm shaft, the relatively young Takahashis I have used all use that same M4 attachment under the focuser. I used my digital calipers to measure the length of the thread of the stock two-point head that comes with the stock focuser and added the depth of the mounting rail. Probably goes without saying that one can usually be purchased at a big box home improvement store or ground down from the odds and ends we all probably have. I have a multi-part kit of stainless steel socket head M[x] bolts I can just grab from.

The Takahashi and other telescopes accessory pack ZWO sells does come with a 5mm to 8mm coupler that works for these telescopes. Just feels like an unnecessarily expensive solution unless the alternative bracket is desired for some reason.

In my photo example I used a more rigid compression-fit coupling that is fatter. Works great, and I like it more than the style that comes with the EAF that bites the shaft with grub screws. Since it is less rigid, although still flexible, I set it up with more care to minimize flex, and I used a couple washers to space out the bracket that came with the EAF so it has enough clearance to spin without rubbing.

Thanks for the info! I will be getting my E160ED tomorrow. Excited to try this out. What size M4 bolt did you use? (length wise)?
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nfol 0.00
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James Peirce:
One thing that strikes me is that you may want to get a compression fit coupling instead of one which bites into the shaft, depending on how heavy the optical train will be.


THank you for your input!

Would you be so kind as to send a link with the coupling that works for you?

I'm still evaluating if I can fit a ZWO EAF on my TOA-150.  (The shaft on the scope is  D = 8,1 mm).
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nfol 0.00
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The focuser on my TOA-150 has a coarse and a fine (1:8) knob. (The latter refitted, Takahashi.)

I wonder if I can fit a ZWO EAF for the fine adjustment?

That would reduce the load on the EAF to 1/8, but increase the travel time 8x.

Those of you with experience for EAF:
Would that solution be feasible?
Would it for example be too slow to work with or give other problems?
Or a great idea?
What do you think?

Best regards,
Niels
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aabosarah 9.31
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N Foldager:
The focuser on my TOA-150 has a coarse and a fine (1:8) knob. (The latter refitted, Takahashi.)

I wonder if I can fit a ZWO EAF for the fine adjustment?

That would reduce the load on the EAF to 1/8, but increase the travel time 8x.

Those of you with experience for EAF:
Would that solution be feasible?
Would it for example be too slow to work with or give other problems?
Or a great idea?
What do you think?

Best regards,
Niels

In general it is not advisable to put the EAF on any fine knob focuser. Not just due to travel time but I think the fine focuser knob is much more likely to get damaged from excessive torque if lets say you reach the end of the focuser with your EAF and you have not set the limits correctly. Also there is not much reason to do so the steps in the EAF are fine enough for focusing on the coarse focusing knob.
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nfol 0.00
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Ashraf AbuSara:
N Foldager:
The focuser on my TOA-150 has a coarse and a fine (1:8) knob. (The latter refitted, Takahashi.)

I wonder if I can fit a ZWO EAF for the fine adjustment?

That would reduce the load on the EAF to 1/8, but increase the travel time 8x.

Those of you with experience for EAF:
Would that solution be feasible?
Would it for example be too slow to work with or give other problems?
Or a great idea?
What do you think?

Best regards,
Niels

In general it is not advisable to put the EAF on any fine knob focuser. Not just due to travel time but I think the fine focuser knob is much more likely to get damaged from excessive torque if lets say you reach the end of the focuser with your EAF and you have not set the limits correctly. Also there is not much reason to do so the steps in the EAF are fine enough for focusing on the coarse focusing knob.

Good and important points. Thank you.
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CCDnOES 8.34
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Although a bit Off Topic I will throw this bit of information in since it might be of interest. I talked to Land, Sea and Sky about two weeks ago since I have ordered an E-160 (to go at home, my present 130 is moving to a remote site). Land Sea & Sky told me that they plan to offer an aftermarket focuser (and as I recall a rotator as well) as a pre-installed package with the Epsilons. They would not tell me who is making it (except that it is not Optec) and said it would be as much as a year before available.

I decided not to wait since they estimate my 160 in about 3 months so I will use either a LEO or the new Hercules but I figured the information might be of interest.

That makes me wonder if they plan to adapt this "mystery focuser" to other Takahashis and/or make it available for separate purchase. I did not think to ask that.
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aabosarah 9.31
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Bill McLaughlin:
I decided not to wait since they estimate my 160 in about 3 months so I will use either a LEO or the new Hercules but I figured the information might be of interest.

Interesting info about the focuser Bill. Did you say they estimate it will take 3 months to get the 160ED? Surprised it is that long. I ordered a 160ED on 5/17 from Land Sky and sea and I picked it up in person on 5/26 just this past weekend (they offered free shipping but they are just two hours drive from my home and wanted to carry it my self in an effort to preserve the factory collimation).
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CCDnOES 8.34
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Ashraf AbuSara:
Surprised it is that long. I ordered a 160ED on 5/17 from Land Sky and sea and I picked it up in person on 5/26 just this past weekend (they offered free shipping but they are just two hours drive from my home and wanted to carry it my self in an effort to preserve the factory collimation).


That may be a default answer for them. They also told me that for the 130 and it took about half that long.
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Supro 4.37
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Bill McLaughlin:
they plan to offer an aftermarket focuser


I would put my money on primalucelabs since they were working on this a year ago if I remember right. I sort of remember a conversation where this was intended for the FSQ106 (and I was asking about the TOA or Epsilon)

Though I'm quite happy with the Leo, I'd love to see another option like that if it comes available. (especially if its preinstalled)
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