Celestron ??

[ThomasMark90]

Good afternoon all.

My grandad recently passed away and whilst the vast majority of his telescopes went to his astronomer friends I have been given a Celestron - although I do not know what it is. I think I have found it is a C6-A OTA?

I have attached photos if anyone has any ideas?

Essentially all I have is what is in the photo - would be lovely to be able to use it as he used to and wondered what I needed to buy to get it up and running? I have no lenses or mounts.

Any help would be greatly appreciated.

 

Edited October 12, 2022 by ThomasMark90

[Elp]

Sorry for your loss.

It looks like a C6 to me as you've guessed with the XLT coatings which is the preferred type, the diameter across the front from outer edge to outer edge should be 180mm if I recall. Looks like your grandfather also fitted  the three Bob's Knobs screws onto the secondary mirror which will make collimation easier but nothing to worry about at this point in time.

The only things you need looking at purchasing are:

1. A 1.25 inch diagonal to put into the existing 1.25 inch visual back adaptor in the centre of the back of the scope.

2. Some 1.25 eyepieces to put into the diagonal. On a budget the best eyepieces are generally BST starguiders or Vixen NPL plossls, a wide 30mm and 20mm will do to start as the focal length of the telescope is quite long (hence high magnification). With the purchase of a 2x Barlow lens, between the diagonal and the eyepiece those two eyepieces will become 15mm and 10mm respectively which will give you even more magnification without having to buy even more eyepieces.

3. A manual alt az mount which may or may not be supplied with a tripod. The tripod needs to be sturdy (thick leg sections, minimum number of leg sections) otherwise any physical touch or breeze will cause the views to vibrate and take a few seconds to dampen down, frustrating if it takes a while. Something like a Vixen Porta mount with slow motion controls will allow fine pointing position adjustment, or an Az4, az5 or something like a berlebach castor, just check with the vendor that there's enough clearance for the OTA tube to move around in altitude without issue and can hold the weight of the OTA with attached accessories. Higher up the range you've got the skytee mount. If you're going to go more advanced later on an equatorial mount may be better like an eq3-2 or above (higher number, larger the mount and the heavier loads they can carry), if you tilt them to 90 degrees they'll work just like an alt az mount.

[Elp]

As a precursor you should be able to see something if you look through the visual back with the scope pointed at a distant object, rack the focus knob (the rubber coated one) from one end of the focus range to the other to check it works mechanically, it'll take a minute or two as the focuser on an SCT has quite some range.

Edited October 12, 2022 by Elp

[ThomasMark90]

Thanks Elp!

He had many many telescopes, unfortunately prior to me viewing them and all the hundreds of "bits" he had they were taken by his 'friends' - that being said, I would very much like to explore his passion more and perhaps turn it into mine. Everything relating to space fascinates me - so thank you very much for your helpful reply.

 

[ollypenrice]

This is a list of UK astronomical societies. (If you're not UK based I apologize.) Getting face to face and hands on would probably be a good start but, that said, you have joined the right internet forum. Welcome.

https://www.skyatnightmagazine.com/advice/amateur-astronomy-societies-uk-ireland/

Olly

[ThomasMark90]

Hi Olly,

Thanks for that I shall take a look! I am indeed UK based, Essex specifically

Thom

[Cosmic Geoff]

The telescope is a C6 SCT.  You have the optical tube assembly (OTA) and to make it usable you need a 1.25" diagonal, an eyepiece (or preferably a set of three eyepieces of differing focal lengths), and a mount.  The choice of mounts is as wide as the sky. 

This OTA was sold bundled with a SE mount, or an Evolution mount, (which cannot normally be bought separately) or an AVX mount (available separately).  Note that all of these are GoTo mounts.  It also seems to be available on a lightweight GoTo mount and a manual + platesolving setup (the Starsense app) none of them available separately.

The OTA could go on a variety of Sky-watcher mounts. I'd suggest the widely available Eq-5 Synscan GoTo mount.   It could also go on a manual AZ-4 Skywatcher mount. (I have successfully used a 127mm Mak of the same focal length + AZ-4).

Note that the prices of some of these mounts may come as a nasty shock.  I would point out though that you will get more out of the OTA, both for visual and for imaging, if you put it on a sturdy GoTo mount.

 

[RT65CB-SWL]

Hi @ThomasMark90 and welcome to SGL. 

Sorry on the of your loss of your grand-father. As other SGL’ers have said, it is an C6/SCT with XLT coatings. I have one myself. [images below].

A few things to invest in to get it up and running…

• a sturdy mount [either alt-az or EQ] and tripod/pillar.
• 1.25” or 2” 90deg. star diagonal. Personally I would choose a 2” one with an SCT fitting... my one is attached to the ETX105... downside is they do make the OTA rear-end heavy.
• a low, medium, high power eyepiece… around 28-32mm for the low power. 
• or a low power eyepiece and Zoom eyepiece. Here I would choose the Baader Planetarium 8-24mm, as it can be used as either 1.25” or 2” if you do not fancy swapping fixed length eyepieces.
• a dew shield… this is a must have. Any catadioptric telescope is a dew-magnet.
• should you wish to attach a camera, then a f:6.3 field flattener/focal reducer [aka FF/FR].
• a full aperture solar filter for solar viewing… these can be ready made or DIY with solar safety film, stout cardboard and self-adhesive tape.
• an optional accessory would be a ’crayford’ focuser, as shown attached on my C6… again the only downside is they do make the OTA rear-end heavy.
• get one or two short 1/4”-20 machine screws, (I think mine are 16mm long), and screw them to the ends of the dovetail bar… should the OTA slip, it will stop OTA crashing to the ground.

Once you have a mount, tripod and dew shield and is outside ready to start viewing, allow it to to acclimatise to the outside temperature. I give mine 30-60 minutes. I notice in your image that it has been fitted with a set of ‘Bob’s Knobs’… these will make collimating the ‘scope easy now or later.

Edited October 13, 2022 by Philip R

[Davesellars]

To keep cost down I'd recommend a manual EQ5 or indeed if you have more budget by all means with the GOTO option, however I found it very easy and find objects with a good atlas.  I wouldn't recommend a manual mount with such a scope that does not have slow motion controls as imho it's just too difficult for tracking an object at higher magnification.  The great thing about the EQ is the tracking is very easy even if only very roughly polar aligned and you can always add on the EQ5 motors or the GOTO afterwards...

Alternatively, you could put up a wanted ad. for an SE mount - you may find someone willing to sell an SE mount (have seen various adverts previously) as they've upgraded and kept the scope.

+1 on the dew shield - this is definitely not an option with an SCT in the UK!

[Cosmic Geoff]

Considering that completing the C6 outfit could cost you a substantial amount of money, you could try 'leaning' on your grandfather's 'friends' to return to you a mount, eyepieces and diagonal.   You might even have a case in law, depending on the exact circumstances.