Prinz 660 telescope

[Alek]

Hello All. I am a new member to this site and have just managed to purchase a Prinz 660 telescope from Ebay, the model that I had in my youth. I remember my father buying it as a Christmas present in 1970 - it was very expensive then and we bought it on HP.

The telescope is remarkably complete, only missing the moon and sun filters and one eyepiece. I have the 4mm, 6mm and 20mm and from memory, believe that I don't have the 12mm?

I wonder if anyone out there has the original instructions and would be willing to scan them and send to me?

Looking forward to stargazing again after a gap of 40 years! Just waiting for the rain to go away

Regards

Alek

[Mr Spock]

I Alek, welcome to SGL

I had a Prinz 550 as may starter scope back in the '70s. I spent many hours scanning the sky with it before upgrading to a home built 8" Newt. I sold the 550 to fund driving lessons...

I hope someone has the instructions for you, there are people here with 660s. Don't bother looking for a sun filter though - they are very dangerous.

[PeterCPC]

Hello and welcome.

DO NOT use a Sun filter that came with these scopes.

Peter

[Mark at Beaufort]

Welcome Alek to SGL and congratulations on the purchase of the Prinz 660 telescope.

As previous stated these scopes were supplied with a Sun Filter - they are extremely dangerous. If placed into eyepiece the Sun's rays will focus on the solar glass filter and it will crack leaving you BLIND.

You will find a great detail of information on all aspects of astronomy on the SGL website - so ask whatever you want.

[laudropb]

Hello and a warm welcome to the SGL.

[Dave Lloyd]

Hi Alex, welcome. There's a good reason the sun filter is missing.

[Fozzie]

Hi Alek.. Welcome for another rainy and damp part of Yorkshire..!

Nice scope, might have been looking at that myself! Have a look at this thread on various adaptors for using 1.25mm ep's instead of the .965mm ones.. If that's of use to you!

http://stargazerslounge.com/topic/172189-prinz-660-refractor/

Clear sky's

Fozzie

[Alek]

Hello guys. Thanks for the warm welcome and advise. How things have changed. When I had the telescope as a child, I frequently looked through the sun filter, though I wouldn't use it today!

[Roy Challen]

Hi Alek, welcome to SGL

I have the instruction for this scope I'll scan them and email later - out and about at the mo. Could you PM me your email address please.

It's a good thing that the sun filter is missing. They're dangerous.

Have a search for threads on here about this scope, there have been a few recently, which I keep an eye on as I have one myself which is getting renovated. I'm certainly not an expert on them, but I'll try to help any way I can

Roy

[RT65CB-SWL]

Hi Alek and welcome to SGL.

I too used to own a Prinz 550. I purchased it sometime during 1977-78 and sold it in 1994. I found the H20 & HR12.5 were OK, but the SR4 was not that good in my opinion. I still have the Sun/Sol filter, but never used it.

[JamesM]

Hi Alek and welcome to the forum. Hope you are able to find those instructions but you might want to consider posting a request over on the equipment section as more people visit there.

Clear skies

[badger111]

Greetings from Maldon, Essex

[Pete Presland]

Hi welcome to SGL from Pete in Bedfordshire

[digital_davem]

Hi Welcome

I have a 660, recently acquired as well. I'm fitting it out with more modern parts - I have added a 1.25" eyepiece holder so I can use it with contemporary eyepieces. My coffin box was missing the tripod and most parts of the mount so I've added tube rings and an arc-swiss bar so I can use it on my camera tripod. Casting envious eyes on proper mounts though. One for the future.

My next step is some kind of finder as that is missing from my kit,too.I've ordered a Vixen/synta finder mount and I'm hoping that little screw that holds the stock mount on will be enough - don't fancy drilling the tube.

I happen to have the sun filter. Nasty, dangerous little thing. I was considering destroying it as a favour to someone's eyesight but if you are a completist and promise faithfully it will never be used, I can send it to you.

Cheers

Dave

[digital_davem]

Hi Alek, welcome to SGL

I have the instruction for this scope I'll scan them and email later - out and about at the mo. Could you PM me your email address please.

It's a good thing that the sun filter is missing. They're dangerous.

Have a search for threads on here about this scope, there have been a few recently, which I keep an eye on as I have one myself which is getting renovated. I'm certainly not an expert on them, but I'll try to help any way I can

Roy

Hi Roy

I'd appreciate it you could copy me in on those instructions - there might be something useful there I've missed.

Cheers

Dave

[triton1]

Hi there and welcome to SGL

[michigander]

Welcome to SGL, Alek!

Dana

[glowjet]

Hi Alek and welcome to SGL  you should have some nice Japanese optics in your Prinz 660, if the specification I have found is correct, this is a 76mm x F1250mm scope. However, if this is right, I can not fathom a reason why the 4mm Super Ramsden and the 6mm Huygens will have been originally supplied with the scope, as these give magnifications ( Focal length / eyepiece mm ) beyond the limitations of the main objective, which under absolutely perfect seeing conditions is given for guidance as 50xper inch of aperture, more normally, in this country, this figure can be reduced down to in the order of 25x to 30x per inch of aperture, because of our atmospheric conditions, but there will be exceptions to the rule on those rare exceptionally clear nights, At the moment your 20x seems to be the only useable optic giving 62.5x.

I have an old scope and the views are completely enhanced by using reasonably powered Orthoscopic ep`s, these are still obtainable in the old .965" on such as Astro/buysell or Ebay, but as has been recommended, an adapter to convert to the 1.25" standard, to enable the use of modern optics is the way to go, enjoy the forum  

[seo]

Hi Alek, welcome to SGL !

[Mak the Night]

If it's like this one: http://www.tennants.co.uk/Catalogue/Lots/170422.aspxit looks very nice. 

[digital_davem]

Hi Alek and welcome to SGL  you should have some nice Japanese optics in your Prinz 660, if the specification I have found is correct, this is a 76mm x F1250mm scope. However, if this is right, I can not fathom a reason why the 4mm Super Ramsden and the 6mm Huygens will have been originally supplied with the scope, as these give magnifications ( Focal length / eyepiece mm ) beyond the limitations of the main objective, which under absolutely perfect seeing conditions is given for guidance as 50xper inch of aperture, more normally, in this country, this figure can be reduced down to in the order of 25x to 30x per inch of aperture, because of our atmospheric conditions, but there will be exceptions to the rule on those rare exceptionally clear nights, At the moment your 20x seems to be the only useable optic giving 62.5x.

I have an old scope and the views are completely enhanced by using reasonably powered Orthoscopic ep`s, these are still obtainable in the old .965" on such as Astro/buysell or Ebay, but as has been recommended, an adapter to convert to the 1.25" standard, to enable the use of modern optics is the way to go, enjoy the forum

On my 660 the 20mm seems usable but I haven't really be able to see anything through the 6mm and 4mm ortho! Not sure why, just a fuzzy patch of light full of hairs, dust and spiders!. 

The view from modern 1.25" inexpensive plossls is incomparably better.  I have a 25mm and a 12.5mm. I'm wondering whether I should get a high mag EP for moon viewing as well, but if so which one? Something like an 8mm? Or maybe a barlow?

[Mak the Night]

 I'm wondering whether I should get a high mag EP for moon viewing as well, but if so which one? Something like an 8mm? Or maybe a barlow?

It depends what the focal length of the scope is I suppose. I like anything between around 150-200x for lunar viewing. I'd rather 'Barlow-up' a longer f/l EP than use an 8mm, unless it's a wide angle, even then you have a smaller field stop. 

[digital_davem]

On my 660 the 20mm seems usable but I haven't really be able to see anything through the 6mm and 4mm ortho! Not sure why, just a fuzzy patch of light full of hairs, dust and spiders!. 

The view from modern 1.25" inexpensive plossls is incomparably better.  I have a 25mm and a 12.5mm. I'm wondering whether I should get a high mag EP for moon viewing as well, but if so which one? Something like an 8mm? Or maybe a barlow?

Focal length of the 660 is 1250mm.  My 12.5mm gives me (obviously!) 100x.  Barlowing it would be 200x compared to 8mm which would give 156x.  I have no idea what magnification a 3" classic f16.5 scope will tolerate on the moon. I've seen suggestions on forums that 300x is doable and elsewhere suggestions that 150x is too much. I guess it needs input from someone with hands on experience of this class (preferably model) of scope.

[Charon]

Welcome aboard.

[glowjet]

Focal length of the 660 is 1250mm.  My 12.5mm gives me (obviously!) 100x.  Barlowing it would be 200x compared to 8mm which would give 156x.  I have no idea what magnification a 3" classic f16.5 scope will tolerate on the moon. I've seen suggestions on forums that 300x is doable and elsewhere suggestions that 150x is too much. I guess it needs input from someone with hands on experience of this class (preferably model) of scope.

Magnification is the result of the focal length of the scope divided by the focal length of the eye piece. These basic facts relate to any telescope, in this case a long focal length Achromat of f16.5 with a Japanese quality 76mm objective. With the long focal length, Chromatic aberrations ( blue fringing round bright objects ) should be much reduced compared to shorter focal length scopes with the same aperture.

Magnification, however, comes at a price, as it also involves the ability to resolve the subject under observation. Much advertising is often given over to the high magnifications achievable at 50x and more per inch of aperture, as most of these products are manufactured in the USA where the seeing conditions on average are better than in this country, except for those rare crystal clear night occasions. Bearing this in mind using the 50x as a standard, on a good night the 3" scope could perform well, with reasonable resolution of detail at 150x, never the less, once magnification is pushed beyond these recognised limits, resolution should begin to collapse and the image become blurred.

This is the reason why such as the old basic 4mm and 6mm Huygens eye pieces, are in general unsuitable at magnifications of 312x  and 208x, having said that, there are exceptions to the rule, with a very good quality eye piece and the 3" Japanese objective, pushing the magnification to upper limits on subjects like the Moon, on a very good night of excellent seeing, may well be achievable, but the resolution may well begin to break down, and you may well find that clearer views are better using a lower power eye piece.

Long focal length 3" and 4" Achromat scopes are again being manufactured to-day by specialists, at a price, as they are still popular among some of our Astronomers