Telescope house visit.

[Trevor]

Finally got round to taking the C11 to Steve at Telescope House to get collimated on the bench, Steve’s workshop is full of very shiny things and some very nice brass.

I’m not saying how Steve secretly collimates telescopes but those that have had the job done are exceptional, I now know what perfect diffraction rings look like

Nick if you read this, the Meade you had at Pat’s was put on the bench before it went to it’s new owner and the diffraction ring was perfect.

Cheers Steve had a nice couple of hours.

Trev.

[Tim]

I was interested in the report that went in the last months S@N mag about TH.

So how do we find out abotu the bench collimation? Do we have to tickle it out of you?

[Psychobilly]

and if the tickling doesnt work....

[GazOC]

I secret collimation technique? My curiosity is piqued!!

[Psychobilly]

Aint Google great....

"Technically, you can use at short distances, another 'collimated' scope, as

a light source. In this, a pinhole light source is put at the focal plane of

the 'perfect' scope, and the two scopes are pointed at one another, and left

focussed at 'infinity' (which is another problem with artificial star

collimation, in that unless the baffle tube is perfectly perpendicular to

the mirror, collimation will change fractionally as you focus for closer

objects). The problem with this is that the accuracy of the resulting

collimation on the second scope, is affected by the accuracy of collimation

on the first. However this is how a test-bench 'collimation' system

basically works."

[legion48]

Aint Google great....

"Technically, you can use at short distances, another 'collimated' scope, as

a light source. In this, a pinhole light source is put at the focal plane of

the 'perfect' scope, and the two scopes are pointed at one another, and left

focussed at 'infinity' (which is another problem with artificial star

collimation, in that unless the baffle tube is perfectly perpendicular to

the mirror, collimation will change fractionally as you focus for closer

objects). The problem with this is that the accuracy of the resulting

collimation on the second scope, is affected by the accuracy of collimation

on the first. However this is how a test-bench 'collimation' system

basically works."

Thanks Bill....I say we tickle Trevor anyway.

[zero]

Google may be great, but it ain't what we do..It'll certainly take some tickling :mrgreen:

[Psychobilly]

Google may be great, but it ain't what we do..It'll certainly take some tickling :mrgreen:

Thats the first attempt I'll have to google somemore or get the feather duster out

Billy...

[661-pete]

Trouble with bench collimation by an expert - as far as I can see - is that, however perfectly it's done, the optics are bound to move once you put the scope back in the car and take it to where you want it to be (which in my case would be a ferry crossing and a 400 mile trip...).

At least, that's how it would be for my newtonian. I too, some months ago, enquired about the collimation service at TH and got a quote, for which I appreciate their attention - but alas! I put the idea on hold for the time being.

So: how good a job can I do for myself, armed merely with a cheshire eyepiece and a laser collimator?

[Psychobilly]

My CPC800 definitely needs the expert touch but its fine for the guidescope duties it usually performs....and seeing as its being shipped back and fore around the place all the time it can stay as it is for now....

[Astro_Baby]

Pete if you want spot on collimation for a newt you could get a catseye system for it - expensive but absolutely the last word in collimation.

I dont think theres much truth in newts shifting collimation myself. I was told ages back that the larger a newt the more frequently it will need to be collimated. That may be true but mine was bumped over 3 miles of bad roads at Salisbury and collimation was spot on.

Recently its been lugged up and down the stairs and put in my tiny car a few dozen times, bumped over some pretty dreadful roads and collimation is STILL perfect.

Recently I took the whole scope to pieces to do the flocking - the secondary/vanes were removed from the tube and the primary and its holder taken off and stored while the tube was being worked on.

It was then re-assembled and de-assembled about 6 times as I messed about doing things to the tube at various times and when it was assembled for the final time collimation was out by a tiny fraction. Considering how many times it had been messed about thats either;

a) Amazing coincidence,

A testament to the oustanding build quality of Sky-Watcher,

c) Proof of my superlative collimation skills,

d) Its a myth that newts lose collimation.

I cant decide myself but I'm pretty sure its not (a) or ©

[NickH]

Having had the tickle (and also witnessed an ACF out of the box show almost perfect collimation...good work Meade!), I can vouch that the method used, involving microscopes, will only work if the C11 optics are close to bang on in the first place. Dud Fuller looked at mine, and quote "shame it's a celestron as that's pretty blo**y good!"

Steve's a magician, a craftsman, and a fantastic asset to both TH, and the UK astronomy industry as a whole. I for one, owe him a great debt of thanks for the work he did on my scopes, and for his candid honesty when something is indeed a "pup" he'll be the first to say it. He prides himself in his work, and when Sir Patrick Moore asks you to restore his scopes, you know you must be good..

[NickH]

Finally got round to taking the C11 to Steve at Telescope House to get collimated on the bench, Steve’s workshop is full of very shiny things and some very nice brass.

I’m not saying how Steve secretly collimates telescopes but those that have had the job done are exceptional, I now know what perfect diffraction rings look like

Nick if you read this, the Meade you had at Pat’s was put on the bench before it went to it’s new owner and the diffraction ring was perfect.

Cheers Steve had a nice couple of hours.

Trev.

The optics on that 5000 were excellent, as I said in the review. My gripe with it (as stated in the review) was the integrated dovetail, and the funny "iron filing" type stuff around the very very edge, something which if you use it at night, you would never see in a million years (nor would affect anything you view or imaged)

Me...I stuck it on the Sun in white light...and it showed up.. but, (and this again goes back to the great honesty and help/integrity of the guys at TH), they were candid about the dovetail, and also thought that the filings could have been a one off on that early shipment model.

Optically, I had it up against some much more expensive kit, and it more than held its own..

When Steve says something is good...it generally is..

We have the (probably) best TMB scope ever to pass through his hands (used to re-calibrate the test bench!), and our chairman is like a kid at xmas using it..