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By Cosmic Geoff
With reluctance I am looking to sell my 200mm aperture f5 Helios Newtonian OTA. (Helios is a brand that became incorporated into Skywatcher - this closely resembles Skywatcher OTAs)
The Helios is offered with single speed rack & pinion focuser, tube rings, 22 to 1.25" adaptor, dovetail bar and grab handle for £90 o.n.o. In good condition except that the dovetail bar appears to be discoloured by exposure to sunlight.
I have not used the telescope for many months and with a persistent problem in my right arm my enthusiasm for moving heavy kit around has diminished.
Buyer to collect from North Bucks.
Offered as option with the OTA: EQ5 mount with RA drive + 6 volt sealed lead-acid battery +charger + standard and extra long Dec slow motion manual shafts. £150. Condition - used but working.
If I sell the OTA I will be looking to dispose of its accessories:
9x50 Skywatcher straight finder - in excellent condition except that the small plastic dust cap is missing.
Cheshire collimator, boxed, as new.
Helical fine focuser, range 10mm, ID 1.25", screws into 2"adapter.
3x Datysun Barlow, as new, boxed.
Widefield eyepiece, 22mm f.l., 30mm body (note not 1.25") with built in focus, works well with this telescope.
Plastic collimation cap (no cost).
This bundle would cost around £114 new - offered if bought with scope at £75 o.n.o.
This is the first lights of my ASA 12"N f/3.62 (purchased in 2007) with my Moravian G4-16000 CCD camera using one KAF-16803 chip of 36mm x 36mm (4K x 4K).
The adjustments, collimation, ASA OK3-Z pression screws, asked a lot of attention.
For a precise collimation, i use the CATSEYE XL & XLKP kit.
This is the first 3hrs of exposures taken the last weekend in one night. The second night was too windy unfortunately.
Full Resolution image in 4K x 4K here :
Full Resolution Annotated image here :
All the information below :
Hey guys,im currently on a school trip and brought my celestron firstscope with, tonight we ll be trying some dsos and maybe saturn and jupiter,the telescope itself is not collimated and dirty (on the mirrors)So I wanted to ask.in the scope, there is no primary adjustment screws,only the ones to take it off .Does that mean that its set , allowing me to take it off wash it and back on without having to recollimate the primary?
To put this in perspective, I bought my first SCT nearly ten years ago. And in all that time, there has been one word that has scared me witless (no, that's not a spelling mistake ) ... collimation!!!!
There are so many horror strories around of people scratching corrector plates and simply messing it up completely and making a scope unusable, that I have always avoided it like the plague ... once even preferring to sell the scope I had and buy another one to avoid having to do it [don't you just love the logic of that one?particularly when there is no guarantee they will arrive collimated!]. I've always belonged to the "I don't care about winning, I just don't want to lose" brigade.
Six months ago, I bought an RC6 and recently picked-up a cheshire eyepiece. No corrector plate ("But don't drop the allen key into the tube," the websites warn!). If I'm ever going to do this, now is the time. A quick look earlier this week showed the dot well out of position, so yesterday ... I procrastinated ... o come on, you didn't think it was going to be that easy, did you? But there are clear skies predicted for tonight, so this morning I went outside, set up my NEQ6, plonked the RC6 onto it, pointed it slightly downwards and went and made a cup of coffee. Returning to the scope I started to have a play.
I kid you not. In less time than it had taken me to set up (excluding the coffee), I had the black dot slap-bang in the middle of my white circle. The allen bolts were tight, yes, but not "wheel-nut" tight; not "you need three feet of metal bar wrapped around the allen key to lean on in order to loosen it" tight. And yes, my first move was in the wrong direction ... so what??? It was so monumentally, stupidly easy ... why all the horror stories on the internet?
Am I pleased I set it up outside where there was plenty of space, rather than struggling in the lounge? Yes. Am I pleased I got a cheshire so I could do it in daylight? Yes. Were the ten years of worry that I had endured dreading this day a waste of energy? You bet!
So my message is to anyone who looks at the word "collimation" and immediately becomes a rabbit in headlights ... Action Cures Fear ... seriously, just do it ... if I can do it, ANYONE can.