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Farpoint auto collimator

Daniel-K

By Daniel-K
in Member Equipment Reviews

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Daniel-K

Daniel-K

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just recived this from Bern @ Modern Astronomy a tad slower the normal but it was worth it, the build quality is very good and its super easy to use just align the 4 extra center spots you see and your done, to confirm i stuck in my cheshire and its the best i have ever seen, i tried to get a shot of the misaligned dots so you can see what it looks like, well worth the money

UPDATE 28th March 2013: firstly i would like to retract this statement "to confirm i stuck in my cheshire and its the best i have ever seen, i tried to get a shot of the misaligned dots so you can see what it looks like, well worth the money" secondly apologize to any who bought one of these on this statement. at the time it seemed to work well till Jason ran through a few tests with me then the flaws started to show. i bought a cats eye triple kit on jasons advice as i was using a F4 scope for imaging at the time. when put side by side the catseye AC won hands down on quality. for the extra £10 the catseye AC is money not wasted and will deffenitly give you more precise collimation.

thanks

Dan

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Daniel-K

Daniel-K

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Interesting. I am still using the Cheshire on the kids' scope, and it can be a bit fiddly (at F/4.3, there is not much of a margin). Might have a look at one of these

its a 2" push fit and its a nice snugg fit, if any one owns a fast scope these are a must

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Jason D

Jason D

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its super easy to use just align the 4 extra center spots you see and your done,

Hello Daniel,

I hope what you mentioned above is not all the included instructions. Can you briefly share the complete set of instructions? I checked the Farpoint site for instructions but couldn't find them.

to confirm i stuck in my cheshire and its the best i have ever seen, i tried to get a shot of the misaligned dots so you can see what it looks like, well worth the money

Did you start off with the cheshire/sight-tube then used the autocollimator then back to the cheshire/sight-tube? I am asking because autocollimators are not the right tool to optimally position the secondary mirror under the focuser.

Jason

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Roger B

Roger B

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I also recieved mine yesterday, I tried to follow Dions example on astronomyshed but as he said align the secondary so the marks line up then go back to either a cheshire or lazer. Well when put the lazer back in it wasn't pointing at the centre circle on the primary. I asked Dion if i have to ignore this & just align the laser back to central IE on the laser collimator it self his reply was "Not quite, you also have to be able to see the black spot right in the center which is the reflection of the hole in the autocolli you are looking in". I can't have the AC and the LC in at the same time. I'm gobsmacked that this piece of kit doesn't come with instructions..... Good quality and build but real poor for anyone that hasn't used one of these before ( Like me )

roger

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Daniel-K

Daniel-K

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this is what it says on the paper "successful use of this device requires the instrument to be adjusted has been previously aligned with basic collimation tools such as a laser or sight tube and a cheshire.this tool is for the final precision alignment adjustment step"

my scope was already well collimated by a a cheshire and then a star im not a big fan of lasers unless they have a fixed cell so i would rather use a cheshire. you do have to be sure your collimation is there abouts when using this though

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Roger B

Roger B

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Yes i collimated with my laser first, then i inserted the AC and adjusted the secondary to bring the doughnuts together. When i re inserted my laser it wasn't pointing in the doughnut, was quite a bit off touching the outer of the circle.. I don't think that my center circle on the primary would be that far out..... dion says you should go back and forth from AC to LC using the LC to adjust the primary. but his comments are conflicting...

Roger

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Jason D

Jason D

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Yes i collimated with my laser first, then i inserted the AC and adjusted the secondary to bring the doughnuts together. When i re inserted my laser it wasn't pointing in the doughnut, was quite a bit off touching the outer of the circle.. I don't think that my center circle on the primary would be that far out..... dion says you should go back and forth from AC to LC using the LC to adjust the primary. but his comments are conflicting...

Roger

I agree. Re-iterating between a single pupil autocollimator and unbarlowed laser does not make sense.

assuming you laser is very well collimated itself ?

Or the autocollimator could be out-of -alignment. Miscollimate until you can see all 4 reflections of the center spot then rotate the autocollimator 180 degrees. If the reflections move a little (around 1/4 of the center spot diameter) that is OK but if their movement is significant then the autocollimator does not have enough accuracy to improve your collimation beyond a cheshire sight-tube.

Jason

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Jason D

Jason D

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You need to conduct the test with all 4 center spot reflections visible and unstacked which means you do it on a slightly miscollimated scope.

Roger stated that he did not receive instructions with the product. Dan sounded like he did. Can someone point me to the instructions – if they exist?

Jason

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Roger B

Roger B

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You need to conduct the test with all 4 center spot reflections visible and unstacked which means you do it on a slightly miscollimated scope.

Roger stated that he did not receive instructions with the product. Dan sounded like he did. Can someone point me to the instructions – if they exist?

Jason

I got what dan did, Just a piece of paper saying " Successful use of this device requires the instrument to be adjusted has been previously aligned with basic collimation tools such as a laser or sight tube and a cheshire. This tool is for the final precision alignment adjustment step". That's it it doesn't tell you a procedure on "how to"

Roger

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Tim

Tim

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I might be barking up the wrong tree completely, but isn't the far point a cheap alternative to the Cats Eye stuff? Although the twin pupil Cats Eye AC isn't much dearer.

Jim Fly's equipment is superbly engineered, hence the price tag, but apart from Dion's anecdotal sales video there doesn't seem to be much info around about these?

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Rustysplit

Rustysplit

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Tim, I agree. I was a bit concerned when I first used the Farpoint that it seemed incredibly sensitive to rotational movements. I also noted that no matter how many iterations of Farpoint then cheshire/barlowed laser I was doing the results through the Farpoint always seemed the same and largely unimproved??

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Jason D

Jason D

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There's no clear printed instructions that come with the auto coli just what I quoted I got my infirmation on how to do it on flo website as they have a similar product udnder the cats eye brand

That is surprising. I wonder why!!!

Understanding how to use “CDP” procedure is highly useful for single pupil autocollimators.

Jason, I have just tried the rotating of the Farpoint whilst miscollimated, and the reflections go from all visible to all out of the FOV in 180 degs!! Could this also be caused by a badly aligned focuser?

This is not a good sign. Your autocollimator will not improve your collimation – if not making it worse. Autocollimators need to meet a high standard of quality and precision to get that extra accuracy.

Interestingly, Dan reported he hardly noticed any reflection shift. I wonder if there is a consistency (Q&A) issue at Farpoint. Malcolm in another thread reported a huge shift for the rotation test – he even included photos. As I mentioned, little jitter is OK but shifting reflections out-of-FOV is excessive.

Jason will likely put me right, but I think the mirror within the auto collimator has to be precisely positioned to be accurate. Any tilt and...well.....

You are correct, Tim. The mirror has to be flat, highly reflective, and precisely squared to the barrel. In addition, the shoulders of the tool should be precisely flat and squared to the barrel.

Jason

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Daniel-K

Daniel-K

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What I do notice is that the slightest of touch of the focuser moves the alignment . I'm not that fussy as long as the collimation is there or there abouts. I'm tempted to prefer the cats eye from FLO and compare the two and do a write up on them both

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