What have I bought?

[look_up]

I know its not going to give Hubble a run for its money but I won this on Ebay today

Vintage Greenkat Japanese Astronomical Telescope

Circa 1970's - a collectors item

Has a 60mm diameter lens and a focal length of 700mm

Comes with two replacement eyepieces in good order in plastic cases - 6mm, 20mm, two sun viewing lenses and 2X Barlow

In very good condition, complete with tripod and wooden case

all for the princely sum of just under £12.52.

Its just to get used to tinkering with a scope I guess. At worst if its rubbish its something for the kids to try out and I get a nice wooden box to put stuff in.

What could I expect to see with this in comparison with my 10x50 binoculars?

[Daniel-K]

i think your bins will be better i have a simlar old tasco takes 0.925 eyepieces they are ok observing the moon and the planets though, i got mine about the same price but not with t a nice box like yours

[look_up]

Part of it was impulse, part the wooden box and part tripod for stability as Im struggling to get the tripod sorted for the binoculars. Eyepieces are new on me so I guess I'll do my usual fiddle and see what they do.

[Obi Wan Ken00bi]

At least it looks much better in the living room then my computerized setup with wires and ugly bits of metal sticking out...

good luck with it!

[Steep]

Worth the twelve quid just for the box

[nightfisher]

looks like a prinz astral 400, not bad and if you adapt it to take 1.25 ep`s it should give "better than you expect" lunar views, i had one and it was rather good on lunar

[ronin]

Looks interesting, 60mm 700mm focal length I assume that the quote relates to the scope.

Cannot recall Greenkat in detail but do seem to recall the name.

Please ignore the "sun viewing lens" they will be a danger, only mention it in case.

Should be decent on the moon and if the eyepieces are OK then point the thing at Jupiter, suspect you will see a couple of bands and whatever moons are present. I do however suspect that the 6mm is too high for the scope and 20 a bit low, a 10mm would have been about right.

There are a reasonable number of clusters that it should be fine on, go point at Orion nebula.

For £12:52 you cannot really go wrong and I suspect you have picked up something to be a talking point and a bit (lots) of fun. Looks as if it has been taken care of.

[look_up]

I'll avoid looking directly into a nuclear furnace then, probably best.

The eyepieces are new on me so the 6mm too high/low is a mystery at the moment. Guess I'll be getting my head around that soon.

Picking it up tomorrow so I'll no doubt have a great view of the clouds for a few weeks

Sent from my HTC One X using Tapatalk 2

[astronymonkey]

Hi Look_up,

well done, good purchase.

I used one of these for years as a kid and still have it today for showing my kids the moon and planets....although you can see some other deep sky objects and double stars with it.

With scopes there is a limit to how high you can push the magnification on a scope before you just start magnifying a blur. For a 60mm scope this is approx 120x magnification.

To calculate what magification your lenses will give divide the focal length of the scope (700mm) by the focal length of the eyepieces (6mm or 20mm) so this will give 116x and 35x but the barlow will basically double these figures.....so in theory you can use the barlow with the 20mm eyepiece to give 70x magnification but it won be worth doing this with the 6mm lens as this would give 232x which is way above the limit for your scope.

Hope this helps, and enjoy your new toy.

[Paul M]

Looks just like my old Prinz refractor from Dixons I got for Christmas as a boy in the mid 70's.

I discovered the universe with it. Admittedly it was in the days when big scopes were rare and expensive and before books full of stunning amateur astrophotography had jaded my expectations of eyepiece views.

In all honesty I reckon I saw more objects with that scope than I have with the 6.25 in equatorial newtonian that superseded it some 10 years later.

[look_up]

To calculate what magification your lenses will give divide the focal length of the scope (700mm) by the focal length of the eyepieces (6mm or 20mm) so this will give 116x and 35x but the barlow will basically double these figures.....so in theory you can use the barlow with the 20mm eyepiece to give 70x magnification but it won be worth doing this with the 6mm lens as this would give 232x which is way above the limit for your scope.

Hope this helps, and enjoy your new toy.

Couldn't have asked for a better explanation. I tried to explain aperture to a friend once, smaller number bigger opening etc. Didn't go well.

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[look_up]

Well just picked it up and it looks like I've got a Sunday afternoon of figuring out what goes where as it's disassembled.

At least I've got a picture for reference

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[lensman57]

I know its not going to give Hubble a run for its money but I won this on Ebay today

all for the princely sum of just under £12.52.

Its just to get used to tinkering with a scope I guess. At worst if its rubbish its something for the kids to try out and I get a nice wooden box to put stuff in.

What could I expect to see with this in comparison with my 10x50 binoculars?

Hi,

It is a good buy considering the nice box and the wooden tripod, makes a very good ornamental display item and OK for the Moon too. I had one of these in the early nineties, I think that I got it from Argos, returned it a week later and went down to London to the then Telescope house. I wanted an 80 mm achromatic refracor Japanese origin but the price was about £450.00, yes you heard right. I ended up buying a second hand Bosch and Lomb 4" Pro series SC for about £400.00. The mind buggles now that I paid £625.00 from FLO for an SW 100 APO ED Pro with the FF/FR included. How the Chinese have changed the endgame?

Regards,

A.G

[skywatcher58gb]

Hi, I have seen a 0.965" to 1.25" adaptor on Amazon for £7.99, however if you want to go the1.25" eyepiece route the best way would be to buy a 0.965" to 1.25" diagonal. Nippon Scope and Optics have them for £13.99, but I'm sure I've seen them on another web site for about £10.

Good Luck on your purchase.

Dave

[look_up]

Thanks all. Just set it up and it wasn't tricky at all. The only thing I need now is a clear sky and we all know the problems in that department.

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[RichieP]

I would go for the 0.925" to 1.25" diagonal rather than tbe adapter.

I bought an adapter for my Prinz Astral 400 but, owing to the short focus travel of the scope, I found that I couldn't focus on anything further away than the back of the garden. Despite getting some very nice views of next door's cat I had to saw an inch off the end of the telescope tube in order to focus on the heavens.

Richard

[todd8137]

Make a nice guide scope i would have that for it

pat

[look_up]

Awesome! Finally a break in the clouds so set it up an aimed for the moon. Eldest son was suitably impressed with the detail in the craters.

Tried to lock on to Jupiter which was really difficult. After about 20 minutes got it in the eyepiece a day although blurry it appeared to have a black dot/shape/shadow in view. A moon or dust in the eyepiece?

[RikM]

Looks very similar to my late 1970's Prinz Astral 400. I still have it and it gives good views of the moon and you can make out the bands on Jupiter and clearly see that Saturn has rings. Actually, with a proper Baader film filter in front of the main lens, it makes a very fine white-light solar scope.

If you do have the little screw-in eyepiece 'sun' filter, please take a hammer to it. They are not safe at all.

[look_up]

Toughest part was stopping the scope wandering, tends to drift slightly which makes it awkward. Couldn't make any detail on Jupiter out, just fuzzy which was a shame but great at the same time. The sun eyepieces are staying in the box. All in all a fun little session

[look_up]

I would go for the 0.925" to 1.25" diagonal rather than tbe adapter.

I bought an adapter for my Prinz Astral 400 but, owing to the short focus travel of the scope, I found that I couldn't focus on anything further away than the back of the garden. Despite getting some very nice views of next door's cat I had to saw an inch off the end of the telescope tube in order to focus on the heavens.

Richard

What advantages would this give me over what I have at the moment?

Bearing in mind that at the minute my knowledge of eyepieces extends to "its the bit you look through to see the shiney thing"

[RichieP]

Without knowing what specific eyepieces you have it's difficult to comment. There were some very good quality 0.925" eyepieces made, but there were an awful lot of basic, low quality eyepieces made as well. I know you mentioned that the ones you have are replacements, but the ones which originally came with my Prinz Astral 400 were rubbish. I upgraded to some 1.25 Plossl eyepieces and it made a big difference.

If you did want to upgrade your eyepieces, there is a vastly larger range of 1.25" eyepieces available, so an adapter/diagonal would give you that choice.

Richard

[look_up]

Without knowing what specific eyepieces you have it's difficult to comment. There were some very good quality 0.925" eyepieces made, but there were an awful lot of basic, low quality eyepieces made as well. I know you mentioned that the ones you have are replacements, but the ones which originally came with my Prinz Astral 400 were rubbish. I upgraded to some 1.25 Plossl eyepieces and it made a big difference.

If you did want to upgrade your eyepieces, there is a vastly larger range of 1.25" eyepieces available, so an adapter/diagonal would give you that choice.

Richard

All I know is theres a 6mm, 20mm and 2X Barlow, possibly what came as standard I guess. Its just clicked what the diagonal is so I understand now. Diagonal is what the eyepiece sits in and connects to the scope.

[RichieP]

Yes, the diagonal sits between the scope and the eyepiece and puts the eyepiece at a comfortable viewing angle.

These sort of scopes often came with Huygens eyepieces (often indicated by an H preceding the focal length e.g. H20) This is a very basic design dating back hundreds of years which suffers from poor eye relief (i.e. how close you have to have your eyeball to the eyepiece) , false colour and narrow fields of view. Even cheap Plossl eyepieces would be a considerable step up.

[bish]

very similar to my first scope. I'll buy one if I see one going cheap. I never had any star charts as a kid so it was only ever pointed at the moon and bright planets.