Setting up the E160-ED for Full Frame Imaging Takahashi Epsilon-160ED · Dark Matters Astrophotography · ... · 1655 · 60487 · 369

Overcast_Observatory 19.90
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Just got my Hercules focuser/rotator. Will install next week (as I'm imaging this weekend, fires permitting). It has the same positioning as the original Tak focuser and the Leo - so, 56.2mm backfocus...but WITH a rotator built in (so I save 19mm of backfocus, as I was using a Pegasus Astro Falcon). Whoohoooo!!!



Fantastic!  So great to see someone has received the Hercules!  Keep us posted.  :-)
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Overcast_Observatory 19.90
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Ashraf AbuSara:
The other thing is, I spent a lot of time aligning the wholes. They definitely were not crooked, but there seemed to be a lot of play side to side in where you can tighten the screws, while still being straight. How are we sure exactly how centered the focuser is? If the focuser is slightly off center, does it affect the performance of the OTA, or is it all fixable with adjusting the tilt and collimation?




The holes on the OTA are slotted, to allow you to position the focuser relative to the primary mirror.  In this case, centering doesnt really matter other than you need your secondary to be centered under the focuser.  This is part of aligning the mirrors.  You will want to get it as centered as possible left to right though, as the secondary cannot be offset left/right.  Get it as close as you can.  Theres really not that much play in this direction.

As for tilt... DO NOT USE THE TILT PLATE ON THE FOCUSER.  Lock it all the way down and forget it exists.   It is not a useful feature and should not be there.  You CANNOT fix image train tilt by tilting the focuser.  If you have image train tilt (between the corrector and the sensor) you MUST fix that within the image train.  Lock the tilt plate down on the focuser and forget it exists.
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mzaslove 2.41
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Chris White- Overcast Observatory:
Ashraf AbuSara:
The other thing is, I spent a lot of time aligning the wholes. They definitely were not crooked, but there seemed to be a lot of play side to side in where you can tighten the screws, while still being straight. How are we sure exactly how centered the focuser is? If the focuser is slightly off center, does it affect the performance of the OTA, or is it all fixable with adjusting the tilt and collimation?

As for tilt... DO NOT USE THE TILT PLATE ON THE FOCUSER.  Lock it all the way down and forget it exists.   It is not a useful feature and should not be there.  You CANNOT fix image train tilt by tilting the focuser.  If you have image train tilt (between the corrector and the sensor) you MUST fix that within the image train.  Lock the tilt plate down on the focuser and forget it exists.

It's interesting you should say that. That's the part they took out of the Hercules to make room for the rotator...and we didn't need it anyway.
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Overcast_Observatory 19.90
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It's interesting you should say that. That's the part they took out of the Hercules to make room for the rotator...and we didn't need it anyway.




Last year Jeff told me that it was a problem to get rotating focuser and tilt plate within the height requirement.  I told him to get rid of the tilt plate... Bill agreed.

Feature gone and Hercules born.  Although, at the time I was working on putting a Gemini on it.... so glad Jeff recognized the market for a mini-Gemini and got it done.  Looks awesome! 

PS-  I have a Gemini on my refractor and absolutely LOVE it.
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mzaslove 2.41
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I'm glad you said something because now I have more backspace than I know what to do with!
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Overcast_Observatory 19.90
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I'm glad you said something because now I have more backspace than I know what to do with!



https://www.asgastronomy.com/asg-electronically-assisted-tilt-eat-project/
https://pegasusastro.com/products/indigo-oag/


Happy to spend your money for you.  
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jpridder86 2.41
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Good to see Hercules has happened. Anyone else get shipping notice on theirs? I pre-ordered early so hoping I’ll get the notification soon.
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aabosarah 9.31
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Chris White- Overcast Observatory:
Ashraf AbuSara:
The other thing is, I spent a lot of time aligning the wholes. They definitely were not crooked, but there seemed to be a lot of play side to side in where you can tighten the screws, while still being straight. How are we sure exactly how centered the focuser is? If the focuser is slightly off center, does it affect the performance of the OTA, or is it all fixable with adjusting the tilt and collimation?




The holes on the OTA are slotted, to allow you to position the focuser relative to the primary mirror.  In this case, centering doesnt really matter other than you need your secondary to be centered under the focuser.  This is part of aligning the mirrors.  You will want to get it as centered as possible left to right though, as the secondary cannot be offset left/right.  Get it as close as you can.  Theres really not that much play in this direction.

As for tilt... DO NOT USE THE TILT PLATE ON THE FOCUSER.  Lock it all the way down and forget it exists.   It is not a useful feature and should not be there.  You CANNOT fix image train tilt by tilting the focuser.  If you have image train tilt (between the corrector and the sensor) you MUST fix that within the image train.  Lock the tilt plate down on the focuser and forget it exists.

Glad you said that. Saved me a lot of trouble. It also made no sense. On my AG Optical the tip tilt plate is between the corrector and the focuser. I suppose my only recourse to fix tilt is using the OAG tilt plate.
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Overcast_Observatory 19.90
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Ashraf AbuSara:
On my AG Optical the tip tilt plate is between the corrector and the focuser. I suppose my only recourse to fix tilt is using the OAG tilt plate.




The tilt plate there is for aligning the focuser/drawtube with the optical axis, not mitigating image train tilt.  I.E., The tilt plate on your AG is for collimation, not fixing tilt in your images...   With the Epsilon you can just reposition the secondary to align the optical axis with your focuser/drawtube, so you really don't need the focuser to be able to tip. 

If you have tilt in your image train, you may be able to mitigate the symptoms by tilting the focuser, however you arent fixing the problem.  You need a tilt device between the corrector and the sensor if you have image train tilt.  If you are using an IMX455 chip, then you will no doubt have some tilt to fiddle with, especially if you don't get your backspacing absolutely perfect (to within 0.1mm).
Edited ...
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aabosarah 9.31
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Chris White- Overcast Observatory:
Ashraf AbuSara:
On my AG Optical the tip tilt plate is between the corrector and the focuser. I suppose my only recourse to fix tilt is using the OAG tilt plate.




The tilt plate there is for aligning the focuser/drawtube with the optical axis, not mitigating image train tilt.  I.E., The tilt plate on your AG is for collimation, not fixing tilt in your images...   With the Epsilon you can just reposition the secondary to align the optical axis with your focuser/drawtube, so you really don't need the focuser to be able to tip. 

If you have tilt in your image train, you may be able to mitigate the symptoms by tilting the focuser, however you arent fixing the problem.  You need a tilt device between the corrector and the sensor if you have image train tilt.  If you are using an IMX455 chip, then you will no doubt have some tilt to fiddle with, especially if you don't get your backspacing absolutely perfect (to within 0.1mm).

The corrector on the AG Optical is built into the tunnel in the middle of the primary mirror (harmer wynne Cassegrain)  The tip/tilt on the AG Optical is between the corrector and the sensor. The focuser just happens to be in the imaging train between the corrector and the sensor. 

Corrector>Tip/Tilt plate>Focuser>Sensor.

I did use it to fix tilt in my images. It worked, but it is not ideal. 

Either way it brings me no pleasure trying to use the ZWO tilt plate to fix this one. Hopefully not a ton of tilt.
Edited ...
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Overcast_Observatory 19.90
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Ashraf AbuSara:
Chris White- Overcast Observatory:
Ashraf AbuSara:
On my AG Optical the tip tilt plate is between the corrector and the focuser. I suppose my only recourse to fix tilt is using the OAG tilt plate.




The tilt plate there is for aligning the focuser/drawtube with the optical axis, not mitigating image train tilt.  I.E., The tilt plate on your AG is for collimation, not fixing tilt in your images...   With the Epsilon you can just reposition the secondary to align the optical axis with your focuser/drawtube, so you really don't need the focuser to be able to tip. 

If you have tilt in your image train, you may be able to mitigate the symptoms by tilting the focuser, however you arent fixing the problem.  You need a tilt device between the corrector and the sensor if you have image train tilt.  If you are using an IMX455 chip, then you will no doubt have some tilt to fiddle with, especially if you don't get your backspacing absolutely perfect (to within 0.1mm).

The corrector on the AG Optical is built into the tunnel in the middle of the primary mirror (harmer wynne Cassegrain)  The tip/tilt on the AG Optical is between the corrector and the sensor. The focuser just happens to be in the imaging train between the corrector and the sensor. 

Corrector>Tip/Tilt plate>Focuser>Sensor.

I did use it to fix tilt in my images. It worked, but it is not ideal. 

Either way it brings me no pleasure trying to use the ZWO tilt plate to fix this one. Hopefully not a ton of tilt.



Ah ok. You originally said yhe tilt plate was between the focuser and the corrector, i assumed that it was not between the corrector and sensor.  :-)

On the Leo, of course it's below the corrector... which doesn't make sense. 

Thanks for clarifying. Yeah, the zwo tilt plate is not going to be very helpful.  Either the photon cage or the octopi if you want to get it perfect... or... blurX in the meantime.
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aabosarah 9.31
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Apologies I was not clear. I just want to get close enough. Going to attempt a start test tonight.
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aabosarah 9.31
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Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG? 

Maybe if I can bring it out enough I can set a limit in the software to make sure I don't accidentally have my OAG crash into the focuser.
Edited ...
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carted2 4.17
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Ashraf AbuSara:
Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG? 

Maybe if I can bring it out enough I can set a limit in the software to make sure I don't accidentally have my OAG crash into the focuser.


I am using a Pegasus Astro Indigo OAG with my remote setup with the LEO along with a ZWO EFW, ASG Photon Cage and a QHY600 SBFL mono camera. It fits well with no clearance issues.
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aabosarah 9.31
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Daniel Carter:
Ashraf AbuSara:
Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG? 

Maybe if I can bring it out enough I can set a limit in the software to make sure I don't accidentally have my OAG crash into the focuser.


I am using a Pegasus Astro Indigo OAG with my remote setup with the LEO along with a ZWO EFW, ASG Photon Cage and a QHY600 SBFL mono camera. It fits well with no clearance issues.

That's great! So the pegasus astro indigo bolts on the ZWO EFW like the ZWO OAG-L? Do you mind taking a photo of your imaging train? (assuming it is not a remote setup)?
Edited ...
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carted2 4.17
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Ashraf AbuSara:
Daniel Carter:
Ashraf AbuSara:
Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG? 

Maybe if I can bring it out enough I can set a limit in the software to make sure I don't accidentally have my OAG crash into the focuser.


I am using a Pegasus Astro Indigo OAG with my remote setup with the LEO along with a ZWO EFW, ASG Photon Cage and a QHY600 SBFL mono camera. It fits well with no clearance issues.

That's great! So the pegasus astro indigo bolts on the ZWO EFW like the ZWO OAG-L? Do you mind taking a photo of your imaging train? (assuming it is not a remote setup)?


It does bolt on to the ZWO EFW. I think I had to order different bolts from Amazon to get it to work. The bolts from Pegasus were the wrong size for the ZWO.

I have my rig out in New Mexico right now so I am unable to take any pictures.
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Overcast_Observatory 19.90
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Yes, the Indigo oag bolts onto the zwo wheel. It works better than the zwo because the camera holder is slimmer than the one on the zwo oag. 

Also, focal plane is determined by your primary to secondary spacing. If you want to push the focal plane up and away from the scope you need to move your secondary closer to your primary and slide the focuser back a little (to stay centered over the secondary) This is why those focuser mounting holes on the ota are slotted, so you can adjust the focal plane.
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aabosarah 9.31
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Chris White- Overcast Observatory:
Yes, the Indigo oag bolts onto the zwo wheel. It works better than the zwo because the camera holder is slimmer than the one on the zwo oag. 

Also, focal plane is determined by your primary to secondary spacing. If you want to push the focal plane up and away from the scope you need to move your secondary closer to your primary and slide the focuser back a little (to stay centered over the secondary) This is why those focuser mounting holes on the ota are slotted, so you can adjust the focal plane.

That makes sense. Are you still selling that Octopi?
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Overcast_Observatory 19.90
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Ashraf AbuSara:
Chris White- Overcast Observatory:
Yes, the Indigo oag bolts onto the zwo wheel. It works better than the zwo because the camera holder is slimmer than the one on the zwo oag. 

Also, focal plane is determined by your primary to secondary spacing. If you want to push the focal plane up and away from the scope you need to move your secondary closer to your primary and slide the focuser back a little (to stay centered over the secondary) This is why those focuser mounting holes on the ota are slotted, so you can adjust the focal plane.

That makes sense. Are you still selling that Octopi?



I'll also add, that if you are trying to simply change the focuser position when in focus (without shifting the focal plane) you can simply raise or lower the focuser using that gold ring on the bottom.  This would be helpful if the oag hits the focuser. You can lower the focuser a little, but just make sure that your focus position leaves room for travel to be able to do autofocus routines. 

Im not selling an octopi.
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aabosarah 9.31
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Chris White- Overcast Observatory:
Ashraf AbuSara:
Chris White- Overcast Observatory:
Yes, the Indigo oag bolts onto the zwo wheel. It works better than the zwo because the camera holder is slimmer than the one on the zwo oag. 

Also, focal plane is determined by your primary to secondary spacing. If you want to push the focal plane up and away from the scope you need to move your secondary closer to your primary and slide the focuser back a little (to stay centered over the secondary) This is why those focuser mounting holes on the ota are slotted, so you can adjust the focal plane.

That makes sense. Are you still selling that Octopi?



I'll also add, that if you are trying to simply change the focuser position when in focus (without shifting the focal plane) you can simply raise or lower the focuser using that gold ring on the bottom.  This would be helpful if the oag hits the focuser. You can lower the focuser a little, but just make sure that your focus position leaves room for travel to be able to do autofocus routines.

Yes that is what I had suggested and asked about earlier up earlier, just wasn't sure if it would work:

Ashraf AbuSara:
Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG? 

Maybe if I can bring it out enough I can set a limit in the software to make sure I don't accidentally have my OAG crash into the focuser.


Appologies about the confusion. I think someone else offered an Octopi and I think you helped answering questions about it later.
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Overcast_Observatory 19.90
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Ashraf AbuSara:
Yes that is what I had suggested and asked about earlier up earlier, just wasn't sure if it would work:

Ashraf AbuSara:
Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG?




Not quite...I'm not trying to be pedantic, but raising or lowering the focuser does not move the focal plane.  Just want people to be clear here on how newtonian telescopes work. You must change mirror spacing to move the focal plane out or in. 
Edited ...
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aabosarah 9.31
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Chris White- Overcast Observatory:
Ashraf AbuSara:
Yes that is what I had suggested and asked about earlier up earlier, just wasn't sure if it would work:

Ashraf AbuSara:
Did anyone here ever figure out a way to use an OAG with the Leo? Does unlocking the gold ring and screwing the focuser all the way in bring the focal plane out enough to be able to use an OAG?




Not quite...I'm not trying to be pedantic, but raising or lowering the focuser does not move the focal plane.  Just want people to be clear here on how newtonian telescopes work. You must change mirror spacing to move the focal plane out or in. 

Ah I see. That's a good point.
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JCT 0.00
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Daniel Carter:
It does bolt on to the ZWO EFW. I think I had to order different bolts from Amazon to get it to work. The bolts from Pegasus were the wrong size for the ZWO.

I have my rig out in New Mexico right now so I am unable to take any pictures.


Dan- do you remember which bolts you purchased?  I have a Hercules on order and I'm about to finally set up my Epsilon,  so after all this waiting, anything that decreases my component roulette would be great.

JT
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carted2 4.17
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Daniel Carter:
It does bolt on to the ZWO EFW. I think I had to order different bolts from Amazon to get it to work. The bolts from Pegasus were the wrong size for the ZWO.

I have my rig out in New Mexico right now so I am unable to take any pictures.


Dan- do you remember which bolts you purchased?  I have a Hercules on order and I'm about to finally set up my Epsilon,  so after all this waiting, anything that decreases my component roulette would be great.

JT


I don't recall if it was M2.5, M3 or M4 screws. I think ZWO has the size required on their EFW page on their website (I think it may have been M2.5 but im not 100% sure). I ordered a kit on amazon that had multiple lengths of the required size. The PA Indigo OAG needs some longer screws (maybe 10 mm?) to secure it to the EFW so the kit with multiple lengths worked well.
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JCT 0.00
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Daniel Carter:
I don't recall if it was M2.5, M3 or M4 screws. I think ZWO has the size required on their EFW page on their website (I think it may have been M2.5 but im not 100% sure). I ordered a kit on amazon that had multiple lengths of the required size. The PA Indigo OAG needs some longer screws (maybe 10 mm?) to secure it to the EFW so the kit with multiple lengths worked well.


Ah great,  I think you are correct , that M2.5 sounds familiar from my other ZWO EFWs.  I have my share of (life saving or "sanity" saving) metric screw sets - will start there.

Thanks !

JT
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