Quality of Optolyth Lens/eyepieces? (1 Viewer)

I am curious about the quality of Optolyth Lens and Eyepices...

Having heard of them for 20 years and finally picking one up in very nice, mint condition from a member here. (Who shipped it lightning fast). I have some mixed thoughts.

This particular Optolyth is a TBS80HD with a 20-60. It's the newer version with the 2 tone light green/green rubber...Not sure how old but I am guessing maybe from around 2000 or possibly a little newer?

Anyway, I took it out for a quick test. Build quality seems fairly high, rubber armor and florite objective element.
Focus and eyepiece zoom are very smooth and comfortable and I actually like the pull up eyecup.

It's not quite as sharp as I had expected I have to say..In fact I think it may now be the least sharp optic I own. (Including 3 non-ED spotters).
I am guessing it's probably a Zoom Eyepiece factor, as I generally use only fixed Kowa EPs....But lacking experience with Optolyth I really don't know.

How are the fixed Optolyth 20x and 30x (New style) eyepieces in comparison? Are they anywhere the build of a Kowa 30x or 25xLER? An improvement over the Opto 20-60x?

I will probably cap my modest collection with this TBS80, would like to get the best I can from it. If the scope body is having good glass in it, it may be worth the effort to make a thread to bayonet adapter....But if it's known otherwise, please share details!

Slingworks,post 1,
I have investigated some Optolyth telescopes a couple of years ago, so not the new ones. At the time of the tests (see the WEB-site of House of Outdoor -verrekijkers testen en vergelijken) I found the Optolyth telescopes investigated:
- Very well made, solid and with good handling comfort.
- The optical quality lagged a bit behind the competition (like Meopta) as far as brightness and color reproduction was concerned.
I liked nevertheless especially the compact draw tube telescopes and the TB-80 mm draw tube telescope with exchangeable eyepieces like 20xWW, 70xWW, 20X, 30X, 40X, ZOOM EYEPIECE 20-60X. Ihave not tested other ones.
Gijs van Ginkel

The fixed magnification draw tubes eg 30ww x 80 were very good optically at the time (c.1980s). When I worked in the sports optics business I was not impressed by the modern style units both structurally and the image. Personally I thought Kowa and Opticron offered better units, mid price range, around the time through to the early 2000s.

P

I have the straight version and it is optically very good, especially at £140 plus postage.
At least up to the 60x maximum zoom.
I have not tried it at higher power.

I think they probably vary in quality from one sample to the other.

I would do a star test, as the objective may be the cause.
Being fluoride I would not want to allow moisture to get in by taking it apart.

Regards,
B.

I doubt that the objective contains a fluorite (calcium fluoride crystal) element. More likely is a fluoride containing glass such as Schott FK-5.
The major producer of fluorite lens elements is Canon Optron and the only users I am aware of are Borg, Kowa, Takahashi, Vixen and, of course Canon themselves for some camera lenses.
Like Binastro, I also think it unlikely that the zoom eyepiece is responsible for any shortcomings. However, I have an old Optolyth brochure and price list from 2010, where an astro adapter, part no. ZUB-24068 is listed for €53. In combination with an inexpensive astro eyepiece this could be an alternative.

John

Hi,

I remember one HD example which was not impressive - ok at 30 but not beyond.

Joachim

So many great replies.

I may try the adapter mentioned if i can track one down and try a Pentax eyepiece for once. I've never tried a Pentax EP and I've read they're pretty good...

Tringa45 it may be as you say, ED glass. I only echoed what was written on the scope foot. "Florite lens."
I looked on the Website and it says "Florite Crystal" but who knows....Either way I think is pretty good.

I'll try the star test when I get a clear night and see how it tests out.

Gijs van Ginkel I also find the "Mini" 80mm draw tube scopes very interesting, especially with the interchangeable eyepieces..But they are very pricey here in the USA...In fact the entire line of Optolyth is pricey. I wondering if they (actually) sell many?

Hi,

the Optolyth page touts CaF2 for the HDF version. You can test it with a green laserpointer. If you shine that into the objective, you will see two reflections connected by a line where light is scattered by impurities in the glass - that is the glass front element and just two reflections for the CaF2 crystal back element which doesn't show that scattering. I can clearly see this in my old Kowa (thanks to Henry for the trick).

The Optolyth 80 HDF bodies are 1200-1300€ over here - so more a midrange model...

PS: you can just hold an eyepiece inside the bayonet and try to get to focus for a quick test... with 1.25" astro EPs you can often remove the barrel (but make sure that is actually empty and doesn't have a barlow element in there). Just be careful to keep the barrel pointing up when unscrewing it and hold the EP over a soft surface... some surprisingly high quality EPs tend to spill the beans, erm lenses when the barrel is unscrewed.

Joachim

I have 2 Optolyth 100 from the 90ies. As you can find at cr-telescopes at http://www.pt-ducks.com/ I like them (also liked 2 80 samplesI looked through), but think that the weakest link are their eyepieces (there are also sample variation within scopes and eps...).
I assume you have the latest zoom version (the compact) and the scope version should already reach focus with astro eps - my older scope doesn't.
The compact zoom version has wider AFOV at maximum magnification and smaller at lower, when compared to the previous version. However I found that it has lower definition the best of the previous one (I have one worst...). The fixed eps have larger AFOVS and higher definition the the zoom but for the same cost you can find better astro eps alternatives - the Optolyth have the compactness advantage.
For zoom, I like very much the Baader Hyperion - better definition and colours, larger AFOVs, but a bit less eye-relief for eyeglass user like me. It can be paired with barlow elements for higher mags.
For fixed alternatives there are many alternatives - see the link I mentioned above, for the 5mm test, but are also many lower power alternatives like the XW, Baader Morpheus, TV Delos, Nikon SW ..., including several AFOVs solutions (mentioned the best around 70º).
Don't know if you have any astro-ep but you should make sure these reach focus before investing on these - if you don't have any, you can purchase a low cost astro-ep to test or order from a seller with good returning options.
I'm curios to test a recent sample to see if there are any quality improvements but haven't seen any new samples.

DRodrigues thanks for the link. I read it twice.

I have a brother who swears the 100mm Optolyth is the best scope made. His opinion may be a bit skewed as he has different needs for a spotter than most.

I tried a 'star test" of my Optolyth the other night. I'd say it has strong astigmatism if I understand it correctly...
it blurs out very heavily to the upper right and then lower left on either side of focus at 60x.

I tested a few of my other spotters as well and it's hardly noticeable in any of them. The Optolyth seems severe in comparison...

I also tested a 20-60x Kowa zoom on all the optics including the Optolyth with a hasty adapter made from a couple O Rings...View improved a little, but not much to my surprise. Usually when I fit a kowa EP to an optic it's a good improvement....This time not so much....

In the daylight I tested it again with the original zoom and Kowa EP's and against my TSN 82sv....
Surprisingly the 82sv with standard glass is somewhat superior in spite of some minor CA. It's slightly sharper and brighter. It's also easier to use on the eyes.. I find the Optolyth causing eye fatigue after some use....

What I do like is the smooth, fine focus wheel, rubber armor and probably unlike most, I like the warmer view.
(from past ownership of older Swarovski and Russian glass). The rubber eyecup on the EP is also great.

I am starting to doubt if I have a lesser quality build, but rather that Optolyth isn't the top brand I used to think it must be...Rather Germany's version of Burris?

It's a nice optic overall, just not top shelf. I did get it very reasonable and it's in like new condition.

I think that Optolyth is seriously overpricing their product line though...This spotter is retailing here in the US for around 2k......And I find it bested by one that retails for $850?

I had it out again this am, and noticed something interesting...

When I sight an object 400yds or so away and roll the focus in a smooth, deliberate manner to bring the object into focus, the object moves....

So, to clarify, when I roll the wheel, right when it's brought into focus, the object moves from right to left when it leaves focus. I can actually see it move a fair amount. (Equal to about 1ft at 400yds). All in one fluid smooth uni-directional move of the focus wheel.

Is this astigmatism? Or a defect of another sort? Or no defect at all? Thanks for the replies in advance.

Hi,

this sounds like the moving porro prism is not only moving along the optical axis (as it should) but also in a way it's not supposed to... not sure which way to result into what you see - maybe tilting slightly around the vertical axis?

Joachim