8 replies to this topic

[jml79]

I have purchased a used C11 in great condition but it has no serial number anywhere and almost no markings to identify approximately how old it is. It has the post 2006 back on it and the original front ring says that it is "Multi-Coated". All I have been able to find out is that this should mean it has XLT coatings (post 2003) and should be compatible with all modern accessories (dew heater, aluminum dew shield, hyperstar etc). it does have a removable secondary. It is painted black and as far as I can tell is not a de-forked model. I has an orange losmandy bar the full length on the bottom. I have a receipt from the previous owner where he bought a dew heater and Celestron losmandy top rail early this year but even the dew heater box is from 2020.

 

Is there any major or minor differences in the C11 between 2006 and today? Does it really matter how old it is if it is newer than 2006? Is there way way to tell how old this scope is?

 

Thanks.

[jmillsbss]

If you can, post photos from in front of the corrector and another view from the rear, so we can see the rear end arrangement and housing.  There are little details here and there that might help date it.  Like you, I really wish there was a plate or decal or something to help.

[jml79]

Sure thing. It has a dew heater installed replacing the original plate retention ring so I have also included a photo of the original retention ring. I don't store it with an open back but I removed the visual back and twist lock for the photo.

 

 

 

Edited by jml79, 15 May 2025 - 09:19 AM.

[jml79]

Using the internet archive, it looks like C11's in early 2015 didn't come with the removable secondary but by mid 2015 they had them. Not sure if this is true though, I am only going by the images on the Celestron website at the time. They may just had not updated the photos. Using the internet archive, Celestron changed the images of the C11A-CGE in late May or early June of 2015. Before that date the images show a non-removable secondary and a plate retention ring with no writing on it. The tube colour also changed from a dark grey to gloss black. I can not see any difference in the scope since then. The current scope looks identical to mine and so does the June 2015 scope. I am actually pretty sure that the images on the site today are the exact same images as June 2015.

Edited by jml79, 15 May 2025 - 09:56 AM.

[jmillsbss]

It has a recent secondary housing design.  It certainly looks like a post-2015 scope.  I've read where there's possibly a serial number on the back of the secondary housing, or somewhere on the secondary, which wouldn't necessarily include a date of mfr., but if you have that number,  there are resources online that have some information about the numbering details.  I think the dovetail has been put on the wrong side, but this probably doesn't matter and may have been done for a convenience when handling or mounting.  It almost certainly has an aluminum tube, but a magnet would easily verify that.

 

May be that just knowing it is a post-2015 standard model C11-A is as close as you can get, but it looks like it's in pretty good condition from here.  The date shouldn't be a make it or break it detail, so long as it puts up good images.

[jml79]

Thanks, It has a top and bottom dovetail.

Edited by jml79, 15 May 2025 - 10:27 AM.

[jmillsbss]

Thanks, It has a top and bottom dovetail.

Perfect.  I just couldn't see it for the blanket or whatever it's sitting on top of.  I love top and bottom dovetails!  SO convenient!

[NinePlanets]

The serial number (or some other number?) on a current production C11 is found on a small, shiny silver label stuck on the outside of the tube near the rear cell.

[C0rs4ir_]

Thats a modern XLT version.