Vintage Japanese Zodiac Bino's. Rubbish?

[Lumen Miner]

Hey all!

Just finished 2 hours of cleaning a set of old 7x50 Zodiac branded Bino's.
Have been using them for a couple of years now with filthy prisims and lens / eyepeices.

At one on stage I think there was, several types of mould growing throughout the set.

Totally dismantled them, cleaned all the prism surfaces and re-assembled successfully.

:eyepop: I was amazed at the clarity, the views are crystal clear and I am impressed with them to say the least.
I can see my 70mm refractor gathering a bit of dust, as the views through the binos are extrodinary. Clusters / doubles are popping out everywhere now.

Has anyone else used one of those old Zodiac sets made in Japan? Did they use reasonable glass in them? I haven't had much of a chance trying other newer bino sets. Could I expect better from sets these days for a reasonable price? Or would these old ones be comparable, to something under $200?

[erick]

They look identical to my old Japanese binoculars, but mine are branded completely differently - "Birnie" I think. And Jen brought a set of old 7x50 binoculars to last SVAA camp - again identical, but a different brand name.

Good enough for me as a child and they got me astronomy late in 2006 when I pointed them at Jupiter and the Jewel Box. Also seems to have a nice coating on the outside of the objective lens - I remember using them at night - but looking terrestrially - amazing what I could see in the "dark".

Apart from that, I don't know anything. I haven't tried to pull mine apart. No visible mould after some 45 years!

[supernova1965]

How do you tell the power of BINO's is it more or less powerful the higher or lower the first number and where does the second number come in to it. I hope I have made my question clear I have never been a good writer:thanx:

[erick]

First number is the magnification of the eyepiece. Second number is the diameter of the objective lens in mm. Hence 7 x 50 is a pair with 50mm objective lenses and eyepieces having a magnification of 7 times.

Some top end binoculars allow eyepieces to be interchanged to give different magnifications - often using standard 1.25" oculars.

You will often see identical looking binoculars for sale with different magnifications - often at the same price. Eg 25 x 100 and 30 x 100. Just different non-removable eyepieces fitted.

Some binoculars have a zoom mechanism in the eyepieces allowing a range of magnifications - say 7-30 x 50.

They are often also marked with the field of view. Sometimes in degrees but often in the form of the width of the image in feet at a distance of 1000 yards (or width in metres at 100 metres).

Read up here:- http://www.aoe.com.au/binocular_guide.html

[supernova1965]

Thanks heaps Erick now I got it:thanx::thumbsup:

[chris lewis]

I collect old post war binos like yours. Post war Japan produced the majority of classic porro binos produced prior to the Chinese mass producing them over the past two decades. The post war Japanese binos had to meet with stringent Q. and A. standards at the time. Japan produced literally 100's like the yours under different names. I have heard of Zodiac but not had one.
The binos you have are circa 1970's. Yours are a 'standard 7x50' with the 7.1 degree Tfov and a Afov of 50 degrees.[ 7.1 Tfov degrees X's 7x mag. = 50 degrees Afov.] 7x50's give a bright image via there 7 mm exit pupil [ 50mm aperture divided by 7x mag. = 7.1 mm exit pupil] and traditionally work well in limited light and they excell on very dark skies where your eyes can dilate fully to take maximum advantage of the large exit pupil.
They have have a single coating of Mgf. and Bk-7 prisms - as do the majority of binos released post war to the 80's when multi coatings and then F.M.C. became more the norm for Japanese binos. Optically they are good and still give a very usable image - however more modern medium to high end binos with F.M.C. lens and Bak-4 prisms etc. do offer better light transmission, contrast, resolution of detail and reduction of distracting internal secondary reflections / ghostings. They are not W.P. and esp. in humid conditions internal mildew can be very destructive and even eat away the prism and lens coatings as you have found out. For eye glass wearers the E.R. ['eye relief'] can be restrictive also. They are not 'robust' as such either - so do not drop them.
You were brave to dismantle, clean and recollimate them - just make sure you do have pin point star images at night.
So yes there are still very usable binos that are still superior to most entry level Chinese binos.

Chris

[Lumen Miner]

WoW chris!! Thanks for going to the effort of writing all that, it was precisley what I was looking for!!
That made my day, as these were my grandfathers, passed to my mother, then to me.
I would have almost removed a 1/4 gram of mould, dust from the internals, not a mark or residue or shadows / smudge was left when finished. I actually noticed they packed one of the prisms to fix a defect in the chassis of the binos, I fixed that more adequatley too.

I must say though, I personally would have used a coarser thread on the attachments, as the very fine thread they used makes it difficult to start screwing things back together.


Thanks for your time Chris, it is appreciated, as I have found no other info on them.