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Advice please on collimation tools for N10


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Hi all,

I am completely new to fast astrographs. I understand that accurate collimation is critical for good performance. I will soon be mounting my N10 on my DDM60Pro for the first time. My dealer sold me an unbranded laser collimator. I have experimented with it and it seems to show collimation errors which I guess are to be expected after transport from Austria to Australia. However, I have little confidence in the results as there is so much play between the collimator and its 2" adapter.

Could more experienced users please advise me on what collimation tools they have found to be easiest to use and most reliable and accurate? I notice that ASA recommends Catseye collimators. I have had a look at the Catseye website but I find it fairly confusing.

So what I am really asking for is recommendations on what to buy.

Thankyou

Ian

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Hi Ian,

 

I just received an InfinityXLKP and TelecatXLS, plus the illumination torch. I found it all a bit confusing at first, but used after the LCOL laser collimator the Infinity gave a good check. I find the identification of the four reflections a bit tricky, but I'm sure I'll get used to it!

 

I find the laser gets me very close, but it's important NOT to tighten the holding screws - rather ensuring that the mounting face of the collimator is hard against the focuser face. This also goes for the Catseye tools.

 

Regards,

Mark

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Ian,

 

I own both most popular tools, i.e. the catseye set (Infinity XLK + Blackcat XL) as well as Howie Glatter's tools (along with tuBlug and some other tool for secondary adjustment)... both tools have some weak points that piss me off very much (I am very demanding customer who hates any weak points ever).

 

As MarkS (above) points out, it's essential to not tighten any of the screws, rather to make sure you strongly fit the front side of the collimating tool to the 2" sleeve. I hate this approach, but all the manufacturers are just idiots...

 

strong points of Howie Glatter's tools:

+ using tuBlug (essential thing) you prevent the common tilt (wobbling) issue in the sleeve holder!

+ tuBlug also allows you to collimate from the back end of the OTA and just watch the pattern from behind as usually done with common lasers that visualists use

 

weak points of Howie Glatter's tools:

- since it is a laser, it itself needs to be collimated well in the factory (a random point, if you are unlucky man like me...)

- in overall the laser is lot less precise than Catseye!

 

strong points of Catseye tools:

+ it is very precise (precise-most) tool which in the end renders a weak point:

 

weak points of Catseye tools:

- due to high precision, it always shows me some residual error - I never saw my pattern 100% perfect (using triangles) there's still some error left and I have two sets of both tools (my and my friends one)

- doesn't fix the common wobbling issue like tuBlug (why don't the "idiots" make tools for screwed attachments for us photographers - that would rule out all wobbling/tilt issues and only tilt in camera sensor would be left - I know why, because only 1% of people (like me and few others) are able to detect this stupidity the rest 99% downsize images to 50% and seems to be happy with it)

- using it with bigger then 10" size Newtonian is a problem with ASA as collimating ASA with two different hex keys from behind is VERY uncomfortable (you can't look directly into the infinity and at the same time play with the stupid hex keys...) a man would like to have some webcam looking into the infinity (problem to look into both holes, central and offset)

 

on the other side - when you finish the hard to do collimation of ASA, the ASA is really WELL built and HOLDs collimation!!! this is most important.

 

anyway, the best (random luck) of Newtonian collimation was this:

http://www.astro.cz/galerie/v/uzivatele/Konihlav/misc/CCD+Image+50-highscreenstretch.jpg.html?g2_imageViewsIndex=1

 

but since I let ASA to fix the non-parallel problem with my secondary vane (spider holder) - so now I have much better spikes from bright stars - I did not manage to collimate well and reproduce the unbelievable "luck" demonstrated on the image above...

 

all best

Pavel

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Thanks very much to those who replied. Collimation seems to be a controversial area. I have read as much as I can and there does not seem to be a "best solution" that most agree on. I have ended up ordering a Howie Glatter laser and tuBlug. Time will tell whether I have done "a good thing" or not.

thanks again

Ian

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  • 1 month later...

Hi Ian,

 

I have both the tools as well.  The Catseye I can't get the hang of.  I'm also in Melbourne, perhaps we could hold a workshop on collimation with the Catseye.  You're welcome to borrow it if you like, as long as you teach me how to use it afterwards...

 

Cheers

Stuart

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Hi Stuart,

I received a Howie Glatter laser and tublug just last week. I have tested the laser for its own collimation and it seems very good. I have done a collimation on my N10 with the new tools and, frankly, I found it quite easy. Small secondary adjustments brought the beam into the centre of the main mirror triangle. I then installed the tublug and could immediately see the shadow of the main mirror triangle projected onto the tublug screen. I then found it easy to slightly adjust the main mirror to centralise the shadow. I then removed the tublug and put the laser back and was pleased to find that the return beam now disappeared up the laser hole. So, based on the belief that the N10 would have arrived with only with small errors caused by transport, I hope and believe that I have achieved good collimation.

I do not have the catseye tools. Part of why I chose the Glatter tools is that I could not completely understand the catseye tool method.

I am actually about 4 hours drive from Melbourne. However I would be very interested in cooperating on this (or anything) as apart from this forum I don't know anyone to work with.

Regards

Ian

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Hi Stuart,

I received a Howie Glatter laser and tublug just last week. I have tested the laser for its own collimation and it seems very good. I have done a collimation on my N10 with the new tools and, frankly, I found it quite easy. Small secondary adjustments brought the beam into the centre of the main mirror triangle. I then installed the tublug and could immediately see the shadow of the main mirror triangle projected onto the tublug screen. I then found it easy to slightly adjust the main mirror to centralise the shadow. I then removed the tublug and put the laser back and was pleased to find that the return beam now disappeared up the laser hole. So, based on the belief that the N10 would have arrived with only with small errors caused by transport, I hope and believe that I have achieved good collimation.

I do not have the catseye tools. Part of why I chose the Glatter tools is that I could not completely understand the catseye tool method.

I am actually about 4 hours drive from Melbourne. However I would be very interested in cooperating on this (or anything) as apart from this forum I don't know anyone to work with.

Regards

Ian

 

Hi Ian,

 

That's pretty much what I have done with my Glatter/Tublug combo.

 

Four hours, which way from Melbourne?

 

Cheers

Stuart

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Hi Stuart,

To the east. I am 20 km north of Buchan in the foothills of the Snowy Mountains. Nearest major town is Bairnsdale which is 100 Km from me. So it is very dark and the altitude is 540 metres. Looking forward to first light with my N10 soon. Some clear nights would help.

Ian

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