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GSO 16 inch RC - collimate with an Autocollimator?

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#76 Tom Gwilym

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Posted 07 March 2021 - 02:36 PM

Inline.....

 



#0 - do, don't hesitate. It's truly a great book

The reviews of the book said it was very technical, but I think I've been in this long enough to qualify. I did look at his web page and sounds like he's working on another book that would cover Raspberry Pi, NINA, StarTools....and all the stuff that I use.  I've gone totally Linux / Pi with my home observatory, the club 16 inch is all on Windows, so I mess a bit with both, but prefer Linux at home.  I'll probably buy the book, looks good from the contents page.  I can always buy his next one too.

 

 

#1 - do, worth the small $ for teh helpful upgrade - get them 25mm long (that's a metric thing, hmmm, how to explain modern measurements to a Yank???) ;-)

I'll look into that.  I've seen them and look like a good investment.  Metric is fine with me, it's so much easier then what we use.  I used it when taking chemistry, so easy!

 

#2 - I use my Glatter on teh mount - just point it toward a uniform flat surface on the ground - you're going to readjust anyways. If you are using a laser make sure and rotator your Crayford/focuser around to three uniformly spaced points (120 degrees apart) and ensure the dot isn't moving, you may not have your focuser attachment (or focuser) collimated - this is a BIG scope, minor imperfections are amplified - that dot should not move as you rotate the focuser.

I'm pretty confident in our $900 focuser I just added. The GSO focuser that came with the scope is garbage.  It probably cost me many of my 100 hours cursing at this thin.  Hmm....the floor is a good idea.  I'll have to see if this thing will rotate around and point at the floor. I have a bad feeling that may not work, but I'll check - never had to point at the ground so why would I try that? :-)

 

#6 - it will often look worse in your Tak after it's actually collimated. My advice here, tape over one of the adjustments (usually the top -12 o'clock ones for me) and then make a single very big but precise change (eg: 1/2 turn in or out) on one of them and note what happens. Then try the reverse. Then move it back. Do the same on teh other side. Don't be afraid to make dynamic changes at the start, this will help you dial in the relationship between the changes you're making and what it does to the on-axis coma. Once you've tried each side, then try both - eg: both 4 & 8 o'clock out 1/2 turn and then in 1/2turn (ie: 1 full turn back) to see what it does. You should notice some very clear patterns to the changes. If you don't - call me and we can setup a TeamViewer session.

So leave one of the three locked in place?  I did read someone mention that in one of the many searches I've done.  Seems like a good idea, then at least one of the bolts will hold the original starting position.  I'll add that to my "try this" list.  I did make large movement after I released the mirror and tightened all the 'pull' screws to the stop (or close as I dared when they felt tight). Then backed off 2 full turns, centered it all visually in the Tak scope, then found my FL was closer to 3250mm and stars looked marginally better.

 

#7 - you should be able to get to 8 seconds or so - you might be using too bright a star - a nice, dim open cluster works best - NOT Alnitak ;-) The longer the exposure the more you can remove the atmosphere from the process - same for using a red filter.

I'll try for a dimmer star in a cluster. Part of my problem might be chasing atmosphere in the 2-3 second exposures I'm sure.  Yeah, Alnitak wouldn't be ideal, that flame and horse may be distracting!

 

#8 - good point, the weather here is already awful, if it clouds over again soon I'll know you're sent money and none of us will forgive you

I got lucky with the $900 focuser, we had a week of good skies. Gave up last night and tried my home observatory, but for some odd reason I had horribly high latency on my network so I gave up.  Later it cleared up, maybe some moisture dried up in my Wifi USB antenna?

 

Distorted stars and funky diffraction pattern.

156380230_10224118324922523_293227423118

 

Oh the pain.....stars don't have corners!

156482097_10224118330642666_294328723881

 

If using the DSI method, I'd align the camera so things match up, then try to tighten the bottom right, or loosen the top left of this.  But does it change things?  Not really.  Just drive me closer to seeking new cuss words to add to my vocabulary.

 

157603841_10224141060890908_474183387560


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#77 Tom Gwilym

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Posted 07 March 2021 - 02:43 PM

Yes, I'm seriously thinking that is a problem from the corners and/or elongation of the stars.  I'm not really sure where what would come from, the mirror mount?  An adjustment screw too tight?  Primary or secondary?  I did fix a tight primary by backing it all off as I mentioned. The secondary does have one screw that seems to be at it's end. I'm thinking maybe I need to back off the 3 to an even starting point, the Tak scope it back again. I don't want to touch the center screw since I've heard bad stories about that, and I have figured I can reach close to factory spec FL with the primary.

 

I do have one friend that is safe to help with this. He's an intern from Arizona U (he's taking astrophysics in college) and has been schooling remotely from here in Wisconsin. He's a fast learner on the hardware side of astronomy, and he's been so busy with school, he's pretty well self isolated from the virus.  He's the only person other than my fiance that I dare hang out with. 

Most of the time, I'm alone running up and down the ladder in the dark.

Here is a good visual of our scope.  We made a little video (this is the music only version without commentary). 

 

https://www.youtube....h?v=1WkVMI8_fCU

 

--Tom

 

If yiu are struggling with getting anything to change as you adjust the primary, yiu may have slightly pinched optics. I’m not expert here, but I did it to myself and the bloody thing would not come to more than a crappy collimating until I remedied that.

 

‘’one other thing, it’s hard work with just one person on a 12”, I guess it’s a nightmare on a 16”. Hoping you’ve got a friend. 

 


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#78 xthestreams

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Posted 07 March 2021 - 06:50 PM

 

Inline.....

 



#0 - do, don't hesitate. It's truly a great book

The reviews of the book said it was very technical, but I think I've been in this long enough to qualify. I did look at his web page and sounds like he's working on another book that would cover Raspberry Pi, NINA, StarTools....and all the stuff that I use.  I've gone totally Linux / Pi with my home observatory, the club 16 inch is all on Windows, so I mess a bit with both, but prefer Linux at home.  I'll probably buy the book, looks good from the contents page.  I can always buy his next one too.

 

 

#1 - do, worth the small $ for teh helpful upgrade - get them 25mm long (that's a metric thing, hmmm, how to explain modern measurements to a Yank???) ;-)

I'll look into that.  I've seen them and look like a good investment.  Metric is fine with me, it's so much easier then what we use.  I used it when taking chemistry, so easy!

 

#2 - I use my Glatter on teh mount - just point it toward a uniform flat surface on the ground - you're going to readjust anyways. If you are using a laser make sure and rotator your Crayford/focuser around to three uniformly spaced points (120 degrees apart) and ensure the dot isn't moving, you may not have your focuser attachment (or focuser) collimated - this is a BIG scope, minor imperfections are amplified - that dot should not move as you rotate the focuser.

I'm pretty confident in our $900 focuser I just added. The GSO focuser that came with the scope is garbage.  It probably cost me many of my 100 hours cursing at this thin.  Hmm....the floor is a good idea.  I'll have to see if this thing will rotate around and point at the floor. I have a bad feeling that may not work, but I'll check - never had to point at the ground so why would I try that? :-)

 

#6 - it will often look worse in your Tak after it's actually collimated. My advice here, tape over one of the adjustments (usually the top -12 o'clock ones for me) and then make a single very big but precise change (eg: 1/2 turn in or out) on one of them and note what happens. Then try the reverse. Then move it back. Do the same on teh other side. Don't be afraid to make dynamic changes at the start, this will help you dial in the relationship between the changes you're making and what it does to the on-axis coma. Once you've tried each side, then try both - eg: both 4 & 8 o'clock out 1/2 turn and then in 1/2turn (ie: 1 full turn back) to see what it does. You should notice some very clear patterns to the changes. If you don't - call me and we can setup a TeamViewer session.

So leave one of the three locked in place?  I did read someone mention that in one of the many searches I've done.  Seems like a good idea, then at least one of the bolts will hold the original starting position.  I'll add that to my "try this" list.  I did make large movement after I released the mirror and tightened all the 'pull' screws to the stop (or close as I dared when they felt tight). Then backed off 2 full turns, centered it all visually in the Tak scope, then found my FL was closer to 3250mm and stars looked marginally better.

 

#7 - you should be able to get to 8 seconds or so - you might be using too bright a star - a nice, dim open cluster works best - NOT Alnitak ;-) The longer the exposure the more you can remove the atmosphere from the process - same for using a red filter.

I'll try for a dimmer star in a cluster. Part of my problem might be chasing atmosphere in the 2-3 second exposures I'm sure.  Yeah, Alnitak wouldn't be ideal, that flame and horse may be distracting!

 

#8 - good point, the weather here is already awful, if it clouds over again soon I'll know you're sent money and none of us will forgive you

I got lucky with the $900 focuser, we had a week of good skies. Gave up last night and tried my home observatory, but for some odd reason I had horribly high latency on my network so I gave up.  Later it cleared up, maybe some moisture dried up in my Wifi USB antenna?

 

Distorted stars and funky diffraction pattern.

156380230_10224118324922523_293227423118

 

Oh the pain.....stars don't have corners!

156482097_10224118330642666_294328723881

 

If using the DSI method, I'd align the camera so things match up, then try to tighten the bottom right, or loosen the top left of this.  But does it change things?  Not really.  Just drive me closer to seeking new cuss words to add to my vocabulary.

 

157603841_10224141060890908_474183387560

 

I am absolutely NOT an expert, like not even close, only been doing this for 12 months, but those looked like pinched optics to me. 
 

start by relieving the secondary screws as you suggested (leave the middle one!), it’s possible you’ve got one or more of the three over tight - but also unlikely.

 

then take a look at the Allen key head screws near the fans that hold the primary floatation cell. I made the “mistake’’ of tightening those when I noticed one had come loose and started to foul the blades of one of the fans. Making it over tight I was able to pinch the optics much like yours are now.

 

Note that if you can reach them through the fan blades that it’s easy to snap a blade, don’t be heavy handed OR just take the scope back to the dealer and have it serviced. 
 

it’s also possible you’ve over tightened the push pull screws enough to deform the primary, again unlikely but you never know. 
 

bottom line, those shapes, at least for me, indicate an impossible to collimate scope. 
 

(The club should invest in a book called Star Testing, some great pictures in there to help you interpret what you’re seeing.)



#79 TxStars

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Posted 08 March 2021 - 05:28 AM

.The bolts/screws should only be moving the mirror cells/mount and not pushing on the mirror.

If the bolts are in contact with the mirrors there is a design problem that should be corrected, scope should be returned.

If the bolts /screws are deforming the mirror cell then the scope should also be returned.



#80 Xeroid

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Posted 08 March 2021 - 11:03 AM

Tom Gwilym,

 

Seems to me after spending the past year trying to solve this issue, maybe its time to take a slightly different approach?

 

What If.....

 

You contact Roland Christen at Astro Physics and ask if he can help collimate your scope when its safe to do so?

 

OK, so your scope weights 92 lbs. and its a 3 1/2 hour drive to his place..might be worth the effort for two able body astronomers if he can precisely re-align the mirrors.

 

I have no doubt he has the equipment and expertise to do it well.

 

Betcha it would take him less than one hour to fix it.

 

Yeah, its a crazy idea but why keep suffering with this agony?

 

My $0.02 worth...

 

PS: Might make for a great story in the local newspapers...


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#81 Lead_Weight

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Posted 08 March 2021 - 11:52 AM

I don't know if you all have seen this, but it looks very promising. https://www.cloudyni...nd-collimation/


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#82 Tom Gwilym

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Posted 08 March 2021 - 12:43 PM

I'm not sure of the design of the scope, but do know it's connected to a frame, but not sure how far the bolts go in.  I'm sure they don't touch the mirror, but at this point I really don't know anymore!  Probably something very similar to this.  I did come across and exploded diagram somewhere here on CloudyNights, but this is probably pretty close.

gallery_240808_5653_29387.jpg

 

.The bolts/screws should only be moving the mirror cells/mount and not pushing on the mirror.

If the bolts are in contact with the mirrors there is a design problem that should be corrected, scope should be returned.

If the bolts /screws are deforming the mirror cell then the scope should also be returned.

 



#83 Tom Gwilym

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Posted 08 March 2021 - 01:00 PM

Crazy idea, but a good one.  I wonder if he would be willing to work on something that he didn't produce?  If nothing else, some lessons on how to do this so I could make adjustments myself.  I'd also worry that by the time we get it back home and back on the mount, something would have jiggled or bumped - even a gentle bump - would screw it all up again.  Yeah, I've learned how temperamental these things are. 

 

I'm so tempted still to yank that thing down and put up the old C14 again.  I'm sure I could really make that thing work great - I never tried that one, it was just before my time in the club.  They had just gotten the RC when I moved here 2.5 years ago.  I've kind of been considered the 'expert' since I've done a lot of astrophography previously and have taken a few somewhat decent images with this thing, but still have never had a serious imaging session yet. I've called all the images 'test images' since I've never been satisfied with it.

 

Ok, I'm venting again.....calm down!    :-)

 

 

 

Tom Gwilym,

 

Seems to me after spending the past year trying to solve this issue, maybe its time to take a slightly different approach?

 

What If.....

 

You contact Roland Christen at Astro Physics and ask if he can help collimate your scope when its safe to do so?

 

OK, so your scope weights 92 lbs. and its a 3 1/2 hour drive to his place..might be worth the effort for two able body astronomers if he can precisely re-align the mirrors.

 

I have no doubt he has the equipment and expertise to do it well.

 

Betcha it would take him less than one hour to fix it.

 

Yeah, its a crazy idea but why keep suffering with this agony?

 

My $0.02 worth...

 

PS: Might make for a great story in the local newspapers...

 


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#84 Tom Gwilym

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Posted 08 March 2021 - 01:04 PM

Looks interesting - but complex.

They mention real or artificial star.  Probably a topic for another forum, but I should look into seeing how I can do an artificial star in the 6 foot dome (if possible?). Then I could work on this more and have less seeing issues.

 

I don't know if you all have seen this, but it looks very promising. https://www.cloudyni...nd-collimation/

 



#85 Tom Gwilym

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Posted 08 March 2021 - 01:12 PM

Ok, and artificial star won't work. Easy to make, but still has to be pretty far away.  Unless I put in on the roof the clubhouse across the field.  https://rasc-vancouv...rtificial-star/

 

Looks interesting - but complex.

They mention real or artificial star.  Probably a topic for another forum, but I should look into seeing how I can do an artificial star in the 6 foot dome (if possible?). Then I could work on this more and have less seeing issues.

 



#86 Terry White

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Posted 08 March 2021 - 02:51 PM

Ok, and artificial star won't work. Easy to make, but still has to be pretty far away.  Unless I put in on the roof the clubhouse across the field.  https://rasc-vancouv...rtificial-star/

Tom, I have the same problem in my dome. I'm going to mount a 1/10-wavelength mirror on my weather mast and look at the Sun's reflection off of a polished 1" sphere placed several hundred feet away. The reflection off of a sphere in discussed in Suiter's book "Star Testing Astronomical Telescopes."


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#87 xthestreams

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Posted 08 March 2021 - 04:56 PM

.The bolts/screws should only be moving the mirror cells/mount and not pushing on the mirror.

If the bolts are in contact with the mirrors there is a design problem that should be corrected, scope should be returned.

If the bolts /screws are deforming the mirror cell then the scope should also be returned.

A year later might be tricky! The bolts in question are not meant to be user adjusted, but as mentioned, I turned on the fans one Day only to find one wasn’t spinning, when I checked, one of the Allen key bolts had come loose enough that it was protruding slightly into the blades. (Agree this should never have happened).

when I “fixed” it, I suspect I screwed it in too far and got stars that looked like Tom’s. In fact now that I recall that night of horrors (as mentioned, I’m a n00b, so assumed I killed my scope beyond my ability to repair) I used the Glatter and there was a distinct reflection artefact (what to my eye looked like a caustic curve when light shines through water). The key point being that I was able to collimate it using the Glatter, even in this condition, but the stars were far from satisfactory. I don’t have experience with the grid pattern Glatter but that might help us narrow that down. 

Agree that going to see Roland would be a great move, while you’re there, borrow a RH and hope he forgets you were ever there ;-)
 


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#88 xthestreams

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Posted 08 March 2021 - 09:23 PM

I was thinking about Tom's comments regarding going back to the SCT.

 

Having had both, I really did love the simplicity of the SCT - if you're prepared to put up with mirror flop, dew on corrector, tube currents, etc (or can work around them), then they're pretty much bullet proof.

 

Having said that, I do love my (flawed) GOS 12" RCT and am seriously thinking of getting a 16" for my remote site until such time as I can afford a 17" CDK and a direct drive mount to match!

 

For anyone reading this wondering which way to go, to Tom's point (and not matter which one you choose), expect to add in a high quality motorised focuser (experience tells me the best option is a Nitecrawler - even if you don't need the rotation, you will value the payload capacity - it's my next upgrade).

 

Oh and STRONGLY consider an ONAG, finding guide stars with an OAG isn't as much fun as it sounds (the next upgrade after the NC).


Edited by xthestreams, 09 March 2021 - 03:35 PM.


#89 Tom Gwilym

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Posted 08 March 2021 - 11:10 PM

 

Having had both, I really did love the simplicity of the SCT - if you're prepared to put up with mirror flop, dew on corrector, tube currents, etc (or can work around them), then they're pretty much bullet proof.

 

I've used a 12" LX200 Classic for many years.  Nice optics, but the mount wasn't great at all for autoguiding.  Yeah, there is dew (I had a dew heater and dew shield which did help), mirror flop - used a motorfocus and had the mirror locking bolt installed (after a rough focus with the knob) and had minimal flop. My scope was always outside in the observatory so temps were usually pretty close to ambient.  I got annoyed with the autoguiding, 'retired' that scope and got an EQ6R-Pro and Stellarvue SV102 refreactor with OAG. Less magnification, but it' works nearly pefectly!

 

Having said that, I do love my (flawed) GOS 12" RCT and am seriously thinking of getting a 16" for my remote site until such time as I can afford a 17" CDK and a direct drive mount to match!

Our 16 is on a Paramount ME. With all the stuff I added, balancing it needs to be redone, but I'll get to that. It's a beat, it will tear cables apart with no effort!  But the collimation....ugh!

 

For anyone reading this wondering which way to go, to Tom's point (and not matter which one you choose), expect to add in a high quality motorised focuser (experience tells me the best option is a Nitecrawler - even if you don't need the rotation, you will value the payload capacity - it's my next upgrade).

Featherouch with the matching motor on ours.  Works great a distorting stars one way then the other. 

 

Oh and STRONGLY consider an ONAG, finding guide stars with an OAG isn't as much fun as it sounds (the next upgrade after the NC).

OAG on the 16.  Yes, finding a guide star is a challenge.  But then I find it and it's so dim and blurry PHD only holds it half the time, but then that does lead to collimation again.

 

 


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#90 Tom Gwilym

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Posted 08 March 2021 - 11:12 PM

Good idea.  I'll have to try slewing around and see what I can find that is in view over edge of the dome. A decorative shiny ball wouldn't look bad somewhere nearby. 

 

 

Tom, I have the same problem in my dome. I'm going to mount a 1/10-wavelength mirror on my weather mast and look at the Sun's reflection off of a polished 1" sphere placed several hundred feet away. The reflection off of a sphere in discussed in Suiter's book "Star Testing Astronomical Telescopes."

 



#91 Rasfahan

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Posted 09 March 2021 - 04:25 AM

I overtightened the secondary adjusting screws recently, leading to a pinched secondary. That made my stars look exactly like in your last pictures. I loosened them again and it resolved the problem.


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#92 Tom Gwilym

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Posted 09 March 2021 - 10:14 AM

Good to know. I do have one of my 3 screws that seems tighter than the others. Maybe I should try similar to what I did with the primary and loosen them a turn, then Tak scope back to the center.  I won't touch the center screw since that may cause more trouble from what I've read. I did prove I can change the FL with the primary alone so no need to mess with that one. 

 

 

I overtightened the secondary adjusting screws recently, leading to a pinched secondary. That made my stars look exactly like in your last pictures. I loosened them again and it resolved the problem.



#93 xthestreams

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Posted 09 March 2021 - 02:47 PM

The biggest difference between the primary and secondary adjustments is that the Center screw constrains the mirrors ability to move longitudinally. 
 

the implication being that you need to loosen at least one as you tighten the other. This isn’t the case with the primary.

 

In terms of mirror separation, you will notice there’s a knurled ring around the base of the secondary, near the spider. That can be loosened which enables you to spin the secondary, increasing or decreasing the mirror sep,again Chris’s book explains this. 



#94 Tom Gwilym

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Posted 09 March 2021 - 02:57 PM

After I thought of that and wrote the comment, it did occur to me that I would end up back where I started unless I messed with the center bolt on the secondary.   The primary just kind of 'floats' on it's 3 bolts unlike the secondary.  Well, I'll dump that idea.  I just still have one that I suspect may be too tight on the secondary.

 

The biggest difference between the primary and secondary adjustments is that the Center screw constrains the mirrors ability to move longitudinally. 
 

the implication being that you need to loosen at least one as you tighten the other. This isn’t the case with the primary.

 

In terms of mirror separation, you will notice there’s a knurled ring around the base of the secondary, near the spider. That can be loosened which enables you to spin the secondary, increasing or decreasing the mirror sep,again Chris’s book explains this. 

 



#95 xthestreams

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Posted 09 March 2021 - 03:05 PM

Correct. Just remember that as you’re tightening one to loosen off the other two. I suspect you’re real close to being there! (But with RCTs it’s the hope that kills you! ;-)


Edited by xthestreams, 09 March 2021 - 03:06 PM.


#96 Tom Gwilym

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Posted 09 March 2021 - 03:14 PM

I still wonder if on the secondary if I should just unwind them all maybe 1 turn and try again?

Correct. Just remember that as you’re tightening one to loosen off the other two. I suspect you’re real close to being there! (But with RCTs it’s the hope that kills you! ;-)

 



#97 xthestreams

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Posted 09 March 2021 - 03:26 PM

Personally, I would.

 

Start by getting it "good enough" with the Tak. Remember as you're adjusting the secondary that tightening one (generally) requires that you loosen the other two a smidge.

 

Don't waste hours (and bring a friend to speed it up), line up the donut, get the vanes roughly right and wait until nightfall (or find an artificial star).

 

As we know, this is an iterative process (the essence of this process is that we're trying to get two mirrors perfectly parallel), as you change one mirror you almost certainly need to change the other in response until you converge on the correct solution. The movements should get smaller the closer you get to the point where you SHOULD start chasing your tail, meaning that you're at or close to optimum.

 

If the stars stop being perfect doughnuts then you've either got coma (adjust primary until the on-axis star's coma has gone), ovals (adjust secondary to make them uniform across the extremities of your FOV) or corners (pinched optics, work out what's deforming the mirror) - or seeing, hence red filter (even on a OSC) and longer exposures to help mitigate the effects.

 

If your Paramount ME's computer has TeamViewer I am happy to dial in and be the friend watching the screen as you make adjustments, we'll have some latency to deal with, but we should be able to get close enough to work out what's going on.


Edited by xthestreams, 09 March 2021 - 03:50 PM.


#98 Tom Gwilym

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Posted 09 March 2021 - 04:04 PM

I'm probably only doing one at a time and not releasing the opposite screws enough maybe, then I get the pinched stars.

Maybe the backing off and re-doing would be good then I may not end up with the pinched side.  I wish there was a way to connect a camera easily to the Tak, then I could stand on the ladder with the iPad and do it all at once. 

 

Personally, I would.

 

Start by getting it "good enough" with the Tak. Remember as you're adjusting the secondary that tightening one (generally) requires that you loosen the other two a smidge.

 

Don't waste hours (and bring a friend to speed it up), line up the donut, get the vanes roughly right and wait until nightfall (or find an artificial star).

 

As we know, this is an iterative process (the essence of this process is that we're trying to get two mirrors perfectly parallel), as you change one mirror you almost certainly need to change the other in response until you converge on the correct solution. The movements should get smaller the closer you get to the point where you SHOULD start chasing your tail, meaning that you're at or close to optimum.

 

If the stars stop being perfect doughnuts then you've either got coma (adjust primary until the on-axis star's coma has gone), ovals (adjust secondary to make them uniform across the extremities of your FOV) or corners (pinched optics, work out what's deforming the mirror) - or seeing, hence red filter (even on a OSC) and longer exposures to help mitigate the effects.

 

If your Paramount ME's computer has TeamViewer I am happy to dial in and be the friend watching the screen as you make adjustments, we'll have some latency to deal with, but we should be able to get close enough to work out what's going on.

 



#99 Tom Gwilym

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Posted 09 March 2021 - 04:06 PM

Ah! This might work for solo secondary tweaks.  I do have a small webcam that I can tape on there maybe. 

http://jimstar11.com/TakScopeMod.html

 

 

I'm probably only doing one at a time and not releasing the opposite screws enough maybe, then I get the pinched stars.

Maybe the backing off and re-doing would be good then I may not end up with the pinched side.  I wish there was a way to connect a camera easily to the Tak, then I could stand on the ladder with the iPad and do it all at once. 

 



#100 xthestreams

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Posted 09 March 2021 - 06:03 PM

Seriously, if you can get up on the ladder, I'll talk you through it assuming you have a speaker loud enough on your computer.

 

You probably don't need to redo the Tak - it's already close enough from an alignment standpoint, it's the pinched optics we need to fix and I can see that through the ASI071's feed.

 

Once that's done, we can start tuning the two mirrors.




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