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Celestron C8 Registry

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#401 spacefitz2

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Posted 23 October 2017 - 04:22 PM

This is my first post.

 

Really liking the retro orange C8s, I have purchased two recently, and would like to register them.

 

The first is from Scottsdale, Arizona. I believe it was made in 1980,or 1981. Its serial number is on the secondary holder and is 809057. It was in good/very good condition with original wedge and tripod. It came with a great condition  trunk, two 1.25 Celestron diagonals, Kellners 25mm ,15mm, and Meade 8mm eyepieces, and a Telrad finder. I have not checked the motor dates yet. 

 

The other C8 is an older 1973  Celestron Pacific sandcast model that had been poorly repainted black. Originally thinking it might be a tricolor that had deteriorating paint, I checked this registry to discover that it was made about the end of the transition period between the tricolored C8s and the two-colored ones. The owner was not the original owner and did not know the reason for the bad paint job.

The serial number of this one is on the base and is: 1 1004 3. The motors are a beautiful brass and are stamped 9-72. 

I have repainted the tube with harvest orange spray cans[nothing exotic], and relubed the innards of the ota, and cleaned the optics and re-lubed the focuser. This C8 had no forks or tripod, not even a plug for the rear port, but was affordable at only $225. It had no cord but the seller had a two prong female cinch-jones fitting so I fashioned a cord from a new 3 wire grounded cord and left the ground wire outside the cord with a little fitting to connect  it to the male plug screw to provide a ground.

The scope is very smooth moving now and has no mirror shift when focusing.

 

Optics are very sharp on both of these scopes, I believe. Overall I prefer the aesthetics of the sandcast scope, though both are very handsome and retro. Neither had finderscopes so recently I have bought a period Celestron orange 50mm finder and bracket, as well as a 50mm Celestron Polaris black finderscope.

 

Thank you to James for this registry. It really adds to the C8s lore, and I appreciate your efforts!


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#402 spacefitz2

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Posted 25 October 2017 - 02:51 PM

Here are a few pictures of the C8s I posted above. 

The first picture is of the 1973 Celestron Pacific. It came without a  wedge [in my post I said without forks...oops!], or tripod, or finder.

This is after I repainted the original black tube, and added the Polaris finder. 

The third and fourth photos are showing the 1980/81 C8 that had the trunk ,eyepieces, diagonals, wedge and tripod, and its serial number.

This one has the correct era 8x50 orange Celestron finder.

Attached Thumbnails

  • IMG_0371.JPG
  • IMG_0372.JPG
  • IMG_0410.JPG
  • IMG_0373.JPG

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#403 Magnus Ahrling

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Posted 26 October 2017 - 06:54 PM

Woow  so nice! I also have the 1973 Celestron Pacific and I am very happy with it. Good optics.

 

Thanks for showing the Pictures.

 

/Magnus 57N.



#404 spacefitz2

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Posted 01 November 2017 - 03:38 PM

Hi again,

 

I decided to repaint the parts of the 'black' C8 Celestron Pacific vintage 1973 that I did not do when painting the tube. [See my previous post.]

After taking the scope apart I discovered that the serial number on the base plate did not match the corrector plate serial number.

On removing the primary, I found that on the back, the mirror was marked "Rematched" with the only felt tip slash mark pointing to the focuser! The number on the back of the primary is: 1037. The number on the corrector plate says 1037RM, so the corrector and primary do match.

Again, the serial number on the C8 fork base is: 1 1044 3.

Should this be added to the remarks on the registry for this unit?

 

I am also unsure of the optimal corrector/secondary position because I read the collimation screws should be parallel to the base when positioned correctly. When I position it thus, the etched number on the corrector is not at the usually cited 3 o'clock position. Any advise from the experts on the forum?

The corrector serial number should not be pointing to the focuser position at 9 o'clock, according to the black slash on the primary, should it?

When I first took off the retaining ring for the corrector the corrector number was pointing at about 7:30, but I thought that couldn't be right. Any insight would be appreciated.

 

The first photo is the untouched black C8.

The second and third pics are the corrector number and the primary number.

The last is the completely repainted C8.

 

Thank you,

Todd F.

 

 

 

 

 

 

 

 

 

 

Attached Thumbnails

  • black C8.jpg
  • C8 Corrector plate serial number.jpg
  • C8 Primary Mirror.jpg
  • IMG_0432.JPG

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#405 Starmapper

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Posted 07 November 2017 - 06:18 PM

Hi

  I just found this registry today, and thought I would post my information.  I bought a C-8 back in about 1980, and the only number I can find on it (without dismantling the optics) is from the secondary cap on the corrector plate: 810744.  Optics still seem terrific and motors (RA and added declination motor) work great.  I'm not sure they build them like they used to....

Vintage Celestron C-8_0002s.JPG Vintage Celestron C-8_0003s.JPG


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#406 JakeJ

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Posted 08 November 2017 - 03:19 PM

Resized_20171103_143952.jpeg

 

Orange C8.  I purchased it from the original owner, who picked it up at the factory in December 1979.

 

Serial# 804495

Corrector# 0967


Edited by JakeJ, 08 November 2017 - 03:21 PM.

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#407 JakeJ

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Posted 08 November 2017 - 03:20 PM

Resized_20171103_145020.jpeg

 

Serial # for above 1979 C8



#408 JakeJ

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Posted 08 November 2017 - 03:21 PM

Resized_20171029_132426.jpeg

 

Corrector # for 1979 C8 above.


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#409 jblane001

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Posted 11 November 2017 - 09:30 PM

In August I purchased a Celestron NexStar C8 SN: 928604.  

 

I have a picture of the serial number on the secondary and of the body... it's got a grey OTA.  I would have uploaded them, but I couldn't figure out how.  It won't let me paste.



#410 jblane001

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Posted 12 November 2017 - 03:13 PM

Update: I learned how to attach photos.  So simple.  Thank you Starmapper.  Here are the photos of my Celestron NexStar C8 SN: 928604.

Attached Thumbnails

  • Celestron Nexstar 8 001 - JBL - small.jpg
  • Celestron Nexstar 8 002 - JBL - small.jpg

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#411 tacun

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Posted 24 November 2017 - 11:23 PM

Hello astrofriends, I'm Carlos, I live in Argentina. This is my first publication

 

 

After many consultations, I finally got my c8. I bought it in Optcorp.

Many colleagues are not encouraged to send it to my country, they fear that the mail could break the telescope.

 

Everything arrived fine, perfectly packed. The tube, the fork, the cover, the anti-spray protector, the finder and the wedge are original. The mountain too, but it is not the oldest. They added a Telrad.
The number is 822954. (since 1982, 1983?)

WP_20171124_17_13_10_Pro.jpg

 

It seems to work perfectly.

 

I would need the cable to connect it to the electric current.

 

I subscribed to learn, and your knowledge is very useful. I will encourage you to ask questions. Thank you all.

 

Hug!

 

Postscript: as photos are uploaded?


Edited by tacun, 24 November 2017 - 11:35 PM.

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#412 tacun

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Posted 03 December 2017 - 09:41 AM

I finally learned (they taught me) to take pictures.

Here it is!

Attached Thumbnails

  • YmzZbON.jpg

Edited by tacun, 03 December 2017 - 09:42 AM.

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#413 Masvingo

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Posted 09 December 2017 - 10:40 AM

I'm well overdue for another update!

Many thanks to Mtn2Sea, Synchrome, TCups, agdad, CCD-Freak, Mr Magoo, Rooftop-Astro, Alucard400, spacefitz2, Starmapper, JakeJ, jblane001 and tacun.  It's wonderful to see so many pictures of the iconic C8!

As before, new entries are in blue, and to keep the file size down I've only shown an image of the top part of the list in the attached image below but there is a link to the latest version of the registry below:

Celestron C8 Registry

 

Synchrome - many thanks for the purchase date and the manual date - its good to have another data point to help tie down the dates for the later 8xxxxx style numbers.

 

agdad - great to hear about your rescue job and glad to hear C8 #820289 has finally found a good home.

 

CCD-Freak - nice to hear of another early C8.

 

Alucard400 - I would guess around 1997.

 

spacefitz2 - interesting to hear about and see the rematched optics in your '73 sand cast C8 - thanks for the mirror and corrector pics - and well done with the paint job - it looks great.  And your '80 C8 #809057 is only a couple of hundred units before my C8, #809219.

 

JakeJ - great to have another original purchase date and thanks for the pic of the corrector number.

 

tacun - Saludos!  It is good to hear that your C8 arrived safe and sound - I always worry about the corrector plate if the crate is dropped.  Based on the serial number of 822954 I would guess it was made around 1984.  If you look into the recesses where the motors are mounted in the base you may be able to spot a date (M-YY) for the motors in the long string of numbers running around the side of the motor which should give you a limit for the earliest date that the scope was made (assuming the motors are original). 

 

Here's a picture of my C5 base (which uses the same base as the C8)

 

C5 base.jpg

 

And here's a close up (roughly where the white arrow in the above picture points) showing where the motor date ('4  81' in this case for April 1981) was stamped on this particular motor ...

 

C5 motor.jpg

 

... however, as the position varied from motor to motor you may not be able to get a clear view of where the date is stamped on your motors without taking one of the motors out.

 

If you plan to get a power cable for the base you may also need to change the two drive motors in the base for ones that rotate in the opposite direction if the original motors were for use in the northern hemisphere. Facing the shaft on the motor, for the northern hemisphere I think the motor should rotate counter clockwise whereas for the southern hemisphere the motor should rotate clockwise.

As ever, all contributions, corrections and clarifications gratefully received.  Please keep the numbers coming.

James

 

Edited to add pictures of a motor

 

C8SNV11part.jpg


Edited by Masvingo, 09 December 2017 - 11:20 AM.


#414 Mr Magoo

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Posted 09 December 2017 - 01:07 PM

I just picked up a Super Polaris version of the C8 a few days ago. It has the SN 835860. I'm guessing this is in the 1985 range by what I see. 

BigC has the scope now.


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#415 Greg M

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Posted 17 December 2017 - 08:35 PM

I picked up this beauty this past weekend. The person I bought it from had no idea of age or year his dad purchased it but did say his dad was the original owner. His dad passed away many years ago and it had been stored in a bag in his closet for many years. Serial # 802514 on the secondary cover.

 

OrangeTubeC8-XL.jpg

20171212_195021-XL.jpg

 

Interesting, the University Optics 8x50 finder only has three wires in the reticule? Is that normal or has one fell out?

20171212_201239-XL.jpg


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#416 tacun

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Posted 19 December 2017 - 01:44 PM

Hi.
I can not date the engines, it's too small a number. I'll find it.

 

I want to show you a picture of the base of the fork.

It does not say "celestron" It indicates something of the electric current.

Do any of you have that same sign?

 

 

 

 

Attached Thumbnails

  • WP_20171218_20_16_15_Pro.jpg

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#417 Starmapper

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Posted 19 December 2017 - 02:47 PM

Hi.
I can not date the engines, it's too small a number. I'll find it.

 

I want to show you a picture of the base of the fork.

It does not say "celestron" It indicates something of the electric current.

Do any of you have that same sign?

Yes, I have the same sign, indicating the voltage and frequency needed by the motors.


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#418 Greg M

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Posted 19 December 2017 - 05:18 PM

 

Hi.
I can not date the engines, it's too small a number. I'll find it.

 

I want to show you a picture of the base of the fork.

It does not say "celestron" It indicates something of the electric current.

Do any of you have that same sign?

Yes, I have the same sign, indicating the voltage and frequency needed by the motors.

 

Same with mine.



#419 Greg M

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Posted 19 December 2017 - 06:50 PM

Just a follow up on my post from a couple days ago regarding the new "old" scope Serial# 802514. I've finally got a proper power cord and having no luck getting her to run so I pulled both of the motors out to have a look. Here's the info on my motors. "610  110v 60cy  3w 1rph  364321  2wa-6-4  2-79"

If that 2-79 is a motor date then that would put my scope to somewhere around 79' or 80'.  Hope that helps someone.


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#420 Masvingo

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Posted 23 December 2017 - 11:25 AM

Thanks for the update Mr Magoo and for details of your scope Greg M including the motor numbers.  I've updated the registry accordingly.

 

Celestron C8 Registry

 

Greg, it looks like Celestron changed to the 8xxxxx style number sometime in the 1st quarter of 1979 so depending on the production rate serial #802514 would fit in around mid to late 1979 - no telling how long the motors would sit in Celestron's parts store.  Re the University Optics finder, the third cross hair gives the correct offset for Polaris - the single cross hair and the bottom cross hair of the paired set are centred with the top crosshair of the paired set being offset.  The University Optics ad in S&T for July 1980 shows the finder as "8x50 for Celestron" and says "One of the most popular accessories we have ever offered.  Brilliant images with a wide field of view.  Available with True Polaris North indicator reticle." The price for the standard cross hair version was $49.95 post paid and $53.95 post paid for the True Polaris North model.  Looking at the picture on your other thread I see the finder is marked NS which suggests it was made by Nihon Seiko in Japan who made a lot of the Unitron equipment.


Edited by Masvingo, 23 December 2017 - 12:58 PM.

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#421 Greg M

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Posted 23 December 2017 - 11:43 PM

  Re the University Optics finder, the third cross hair gives the correct offset for Polaris - the single cross hair and the bottom cross hair of the paired set are centred with the top crosshair of the paired set being offset.  The University Optics ad in S&T for July 1980 shows the finder as "8x50 for Celestron" and says "One of the most popular accessories we have ever offered.  Brilliant images with a wide field of view.  Available with True Polaris North indicator reticle." The price for the standard cross hair version was $49.95 post paid and $53.95 post paid for the True Polaris North model.  Looking at the picture on your other thread I see the finder is marked NS which suggests it was made by Nihon Seiko in Japan who made a lot of the Unitron equipment.

THANKS! Good to know the finder is not damaged or missing a cross hair.



#422 gonzalo

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Posted 31 December 2017 - 05:19 PM

Hi!!

 

Happy new year to all.

 

Great initiative doing this C8 archive,  congratulations! I'll tell you my story:

 

I'm Gonzalo and this is my first post in the forum. Like the guy from a few posts ago, I am also from Argentina.

When I was a kid, I remember my father - who was an engineer - loved astronomy. He had a big telescope and he showed me the moon, the planets, stars and other things.

Fast forward 35 years, now I am an engineer also, and I live and work in the US  (Miami FL) . And my father passed away 16 years ago. I never thought about that telescope again.

A few months ago I remembered how he loved astronomy, and it sparked an interest in me also.  So I bought a C90, and looking for information I discovered CN  and started reading and learning about telescopes.

 

So.... Now I am in Argentina visiting my family for the Holidays.  And I thought I should look for that telescope and set it up. I found it in my mother's house,  in perfect shape, and with all it's original accessories.

 

It's a Celestron 8, serial number 802002.   He bought it new, must have been around 1978 or 79  (I'm not sure, I'll try to see if I find the original invoice).

 

The mount is the 220v  50Hz version, to use in Argentina.  I did not try to turn on the motors, but I guess they should run in the opposite direction, if they were made for the southern hemisphere (right?)

Tried to see if I could see the date on the motors, but I could not.

On one of them I could read :  "220 V   50 C"  (cycles).   And on the other, I could only read  AR - 2W  (judging from the other pictures here, the date should be on the right of that, so it's not visible.).

 

I set up the telescope in my mother's patio, and it works great. The diagonal and the eyepieces have some dirt in them, but I could focus the telescope perfectly on some neighbor buildings

 

Accessories:

Mirror Diagonal

Eyepieces (40 mm, 25 mm, 12 mm, 12.5 mm reticle, 6 mm, 4 mm.  How can I find the specs of these eyepieces? are they any good in today's standards?

Porro prism

Drive corrector , I guess to manually tune the speed of the motors - since I assume at that time the motors took the speed from the electricity AC frequency.  (right?)

Filter set

Instruction manual in English , dated January 1978

Instruction manual in Italian.

Solar filter (not pictured)

Barlow (not pictured) , and other tubes , adapters that I don't know.

And a case / trunk, also not pictured

 

I've been driving myself crazy to link the pictures in Google Photos, it works on the preview but then when I try to post I get the error "You are not allowed to use that image extension on this community"

So Im gonna attach a file with a very low resolution, and then the rest of the pictures are on the Google Photos album.

 

c1.jpg

 

 

All pictures are here in a Google Photos album:

 

https://photos.app.g...LVL3fmidkQUqBs1

 

So it's a pleasure and an honor for me to contribute to this archive with my father's telescope.  I would love to take it with me to the US in a future trip , and see if I can clean it and mount it on a modern alt-az mount like a Nexstar go-to or a Porta.

 

Thanks,  and happy new year to all!

 

Gonzalo


Edited by gonzalo, 31 December 2017 - 11:49 PM.

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#423 gonzalo

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Posted 01 January 2018 - 10:10 AM

Update: More pics,  finally I learned how to link to them.   The complete set is still in the Google Photos album.

 

https://photos.app.g...LVL3fmidkQUqBs1

 

Gonzalo

 

 

hDN8fKq2B0T27y6ICasqUyJ7e1TZL3tdcKTyEVoj

 

 

nprY-YHd_CpaTLj-HrI--0VFGZPPlBBt5FjI_TrB

 

 

GrrbDvY0oEc1Fd-yoQAgENJ2StUy2aR5N2JCKS50


Edited by gonzalo, 01 January 2018 - 10:17 AM.

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#424 Masvingo

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Posted 03 January 2018 - 05:51 PM

Hi Gonzalo, and welcome to CN!

 

That's a nice looking C8 there (and nice that you have a C90 as well) and thanks for the details which I will include in the next edition of the C8 registry.

 

Based on the serial of 802002 I would estimate mid 1979, as it would appear that Celestron changed to the 8xxxxx style number sometime in the 1st quarter of 1979. 

 

You are correct that the motors should rotate in the opposite direction to those in C8s sold for use in the Northern hemisphere.  (Of course, if you bring it back to the US then the motors will then be turning in the wrong direction but they are easy enough to swap over if you can find a pair that turn in the correct direction.)

 

The drive corrector would generally be used for astrophotography to adjust the drive speed to keep the scope centred exactly on the target (or a nearby guide star) using the eyepiece with the illuminated reticle (or crosshairs) - that's the 12.5mm orthoscopic (or.) eyepiece with the adapter on the side which should take a small bulb to illuminate the crosshairs and which would be powered from the lamp socket on the drive corrector.

 

You could take photos using either

  • a camera and lens mounted on the body of the C8 (your C8 has the optional piggyback camera mount on the top of the rear cell next to the finder) using the C8 purely for guiding to ensure the camera remains centred on the target during the exposure or
  • using an off-axis guider which attaches to the rear cell in place of the visual back and allows a camera body to be attached (using a T-ring which threads onto the off-axis adapter and has the specific bayonet mount for the particular camera body being attached) and has a small prism at the edge of the field of view which diverts part of the light coming in to a tube at right angles to main body which holds the guiding eyepiece and enables the C8 optics to be used both for guiding and taking the picture - your dad might have had one as you mentioned other tubes and adapters in your post.

There might also be a tele-extender which would screw onto the back of the visual back and allow a camera body to be mounted a few inches behind the visual back so that the eyepiece projects an enlarged image onto the film plane (or the ccd detector nowadays in a digital camera) and which was used for planetary photography. 

 

The eyepieces are a mix of Kellners (marked K) and orthoscopics (marked or) and were good eyepieces in their day.  Nowadays their main disadvantage will be a narrow apparent field of view compared to modern designs like the high end Televues.  However, they should still give good images as one advantage of a scope with a high focal ratio (f10 for the C8) is that they are less demanding of the eyepiece and still work well with the simpler eyepieces, unlike wide-field scopes with low f numbers. They also have the advantage of being lighter and smaller (and cheaper) than the modern wide-field designs.

 

James


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#425 gonzalo

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Posted 03 January 2018 - 10:29 PM

Hi James, thanks for your reply!

Many things are clearer now.  :-)

 

 

The drive corrector would generally be used for astrophotography to adjust the drive speed to keep the scope centred exactly on the target (or a nearby guide star) using the eyepiece with the illuminated reticle (or crosshairs) - that's the 12.5mm orthoscopic (or.) eyepiece with the adapter on the side which should take a small bulb to illuminate the crosshairs and which would be powered from the lamp socket on the drive corrector.

Ahhh!  Got it!!

 

 

You could take photos using either

  • a camera and lens mounted on the body of the C8 (your C8 has the optional piggyback camera mount on the top of the rear cell next to the finder) using the C8 purely for guiding to ensure the camera remains centred on the target during the exposure or
  • using an off-axis guider which attaches to the rear cell in place of the visual back and allows a camera body to be attached (using a T-ring which threads onto the off-axis adapter and has the specific bayonet mount for the particular camera body being attached) and has a small prism at the edge of the field of view which diverts part of the light coming in to a tube at right angles to main body which holds the guiding eyepiece and enables the C8 optics to be used both for guiding and taking the picture - your dad might have had one as you mentioned other tubes and adapters in your post.

There might also be a tele-extender which would screw onto the back of the visual back and allow a camera body to be mounted a few inches behind the visual back so that the eyepiece projects an enlarged image onto the film plane (or the ccd detector nowadays in a digital camera) and which was used for planetary photography. 

 

I see.  Seems strange to use a C8 only to guide for a camera with a normal lens.  But I guess it makes sense for DSOs, for example using a good telephoto lens.

 

 

Regarding the off-axis adapter, and the tele-extender,  I'll see if I have them, now that I have an idea of what to look for.

 

 

The eyepieces are a mix of Kellners (marked K) and orthoscopics (marked or) and were good eyepieces in their day.  Nowadays their main disadvantage will be a narrow apparent field of view compared to modern designs like the high end Televues.  However, they should still give good images as one advantage of a scope with a high focal ratio (f10 for the C8) is that they are less demanding of the eyepiece and still work well with the simpler eyepieces, unlike wide-field scopes with low f numbers. They also have the advantage of being lighter and smaller (and cheaper) than the modern wide-field designs.

I understand.  Maybe I could try a couple with my C90, but I really don't want to take them home to the US without the rest of the things. I don't want to start separating and mixing stuff.  I think I'll leave everything together here, until and if I take the telescope to the US in the future.  :-)

 

BTW, Is the manual something you guys would be interested in, or is it pretty common?

If you are interested, I could scan it and post it here.

 

Thank you!

 

Gonzalo


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