Just Purchased NIB 85mm Zeiss for $1300 (1 Viewer)

galt_57 said:

Oddly enough I've come across another Zeiss 85 message regarding a failed star test. In a followup e-mail he further commented that he checked two Zeiss scopes and they were both the same, so he bought a Leica instead.

Click to expand...

The Alula reviewer came across a slightly duff Leica APO 77, and IIRC commented that all manufacturers were guilty of letting slightly duff scopes get out of the factory. Whether any one manufacturer stands out - as being particularly good or bad - is not clear.

you may have trouble with your filter

Mate you had better be careful. I looked up the Zeiss webbsite for tech details for filtering my Zeiss 85.Guess what.the catch is that thread pitch is 1mm not the standard .75mm photographic type filter thread pitch.This means the thread although correct diameter,will be too fine to fit this lense.BEWARE...DONT FORCE IT.i HAVENT BEEN ABLE TO SOURCE A 86mm 1mm PITCH FILTER ANYWHERE>>>>>>>good luck BROWNIE

Ruger said:

Thanks again for the advice Mick, Mak and Lief,

As I've mentioned, this is my first scope (I've save $ for months) and I want to get it outfitted right, the first time, without the expense of inferior add-ons.

Thanks for bringing to my attention the difference between protect and UV filters. I'll be ordering a protect filter and the opticron case ASAP (the scope is used primarily for birdwatching and hopefully digiscoping secondarily).

Click to expand...

brownie said:

Mate you had better be careful. I looked up the Zeiss webbsite for tech details for filtering my Zeiss 85.Guess what.the catch is that thread pitch is 1mm not the standard .75mm photographic type filter thread pitch.

Click to expand...

There is probably some variation between different filter manufacturers. I believe the switch from 0.75mm to 1mm is right around 86mm. See;

http://www.2filter.com/prices/products/bwregsizes.html

galt_57 said:

There is probably some variation between different filter manufacturers. I believe the switch from 0.75mm to 1mm is right around 86mm. See;

http://www.2filter.com/prices/products/bwregsizes.html

Click to expand...

Thanks for the filter contact,Galt.Will chase one up soon.Turned Australia upside down to no avail.
.....BROWNIE

Leif said:

Given that many BF users own scopes, we thus have the means to do an online scope sample variation survey. In other words, we all post a brief description of how our scope star tests at ~60x, not forgetting scope details. No doubt, given the previous enthusiasm for my suggestions, noone will be interested ...

Click to expand...

I've decided to borrow as many scopes as I can over the next few weeks for star and resolution testing. I'll use the same porcelain power line insulator at about 100m as an artificial star for each star test. For resolution tests I'll be using a chart that was published in "Sky and Telescope" magazine a number of years ago which gives a direct reading of resolution in arc seconds.

Yesterday I borrowed a Swarovski ATS-65HD for testing. This scope produced a very respectable star test. The only manufacturing defect visible was very slight miscollimation, barely detectable and probably of no consequence to the image quality. There was no astigmatisn or pinching. Chromatic aberration was very well controlled with only a tiny amount visible in focus at 60X. There was a moderate amount of spherical aberration, strong diffraction rings on one side of focus, weaker ones on the other side with the strongest of those toward the outside. SA is probably the major factor preventing this scope from from having "diffraction limited" resolution, but it's still a decent result and much less damaging than the manufacturing defects I saw in the Zeiss scope last week. I measured resolution of about 1.9 arc seconds, not quite as good as the diffraction limit of 1.78 for a 65mm aperture but still a good figure for a scope of this type.

The 65HD has one significant optical advantage over the 80HD and all the other "big" scopes. It's focal ratio is F=7 compared to around F=5.8 on the big ones. That might be one explanation for it's good test results. This sample also proves that it is not an impossible dream to purchase a birding scope that is essentially free of manufacturing defects.

henry link said:

I've decided to borrow as many scopes as I can over the next few weeks for star and resolution testing. I'll use the same porcelain power line insulator at about 100m as an artificial star for each star test. For resolution tests I'll be using a chart that was published in "Sky and Telescope" magazine a number of years ago which gives a direct reading of resolution in arc seconds.
[...].

Click to expand...

I started another thread on testing -- since this thread has been drifting away from the original subject. I would really like to find a simple standard resolution chart that anyone could print on a standard laser printer. Maybe for simplicity a simple text eyechart might work (?)

Dave

Dave,

Try Googling "USAF 1951 resolution test". There are many sources for this standard test pattern. I got one printed on a plastic card from Edmund Scientific Co. long ago, but misplaced it. I find the "Sky and Telescope" chart easier to use, but I don't even remember what year it appeared.

I'll put future tests on the new thread and work up some kind of summary of them all at the end.

Henry

galt_57 said:

I started another thread on testing -- since this thread has been drifting away from the original subject. I would really like to find a simple standard resolution chart that anyone could print on a standard laser printer. Maybe for simplicity a simple text eyechart might work (?)

Click to expand...

I've been using Norman Koren's chart. You can find it at:

http://www.normankoren.com/Tutorials/MTF5.html

However, I find that when printing my own hard copy, the very last section of the chart cannot be reproduced faithfully by my Epson 1280 and glossy paper.

Here's a page with links to lots of different charts:
http://www.bealecorner.com/trv900/respat/

I'm not sure how you would apply any of these charts when directly viewing them with your eye.

henry link said:

I've decided to borrow as many scopes as I can over the next few weeks for star and resolution testing. I'll use the same porcelain power line insulator at about 100m as an artificial star for each star test. For resolution tests I'll be using a chart that was published in "Sky and Telescope" magazine a number of years ago which gives a direct reading of resolution in arc seconds.

Click to expand...

Which issue of Sky and Telescope? Perhaps I can order a back issue.

There are no above ground power lines in my neighborhood. I've been looking for a something nearby to serve the purpose and have had not yet found it. Though I have a very nice 1" ball bearing that would do nicely if I could find a relatively high place to place it.

BTW, I have web space available if you want to publish your results somewhere.

Today I ordered Zeiss 85TFL from the same dealer. Could you suggest some simpe tests to find out the optical quality of the scope. It will be my first scope and I don't have any experience in testing optical instruments.
There are so many tests, resolution charts, opinions and counter-opinions available on the web that it's confusing.

henry link said:

I would urge anybody purchasing the Zeiss or any other scope to immediately star test the scope for optical defects. This can be done with a real star or an artificial one during the day (a small shiny convex object reflecting a tiny image of the sun at a distance at least 100 times the focal length of the scope). Manufacturing defects will be immediately visible in the diffraction pattern at 60X which will not necessarily be obvious from just looking through the scope, especially at low power.

I borrowed a friend's 85mm Zeiss scope today for resolution and star testing expecting excellent optics. To my dismay (I had suggested the scope to him based on good reviews) the scope had multiple optical defects, the worst of which were astigmatism and poor collimation. I don't see how a scope this bad ever left the factory.

The odd thing is my friend has been completely delighted with this scope. Like many birders he has come to expect deterioration above 30X so found nothing objectionable in the poor image quality at 60X.

Click to expand...

Ashu said:

Today I ordered Zeiss 85TFL from the same dealer. Could you suggest some simpe tests to find out the optical quality of the scope. It will be my first scope and I don't have any experience in testing optical instruments.
There are so many tests, resolution charts, opinions and counter-opinions available on the web that it's confusing.

Click to expand...

Well, I have the same scope and have tested it using resolution charts I found on the Internet, but I have not "star tested" it - I might get round to it one day. I might be being foolish, and I know a few others here disagree, but I do think I can tell if the scope is faulty or not when I look through it. It is a marvellous piece of kit - both optically and mechanically.

When you get the scope, there are two aspects that do make it different from other top scopes. The first is concerned with its zoom eyepiece. This offers easily the widest view available today, but there is a slight cost for such a wide field of view: the very edges of the view are not as sharp as the centre. This is not a fault and you soon become used to it - it's a trade off for being able to see almost 50% more than the nearest alternatives (the Leica or Swarovski zooms).

Secondly, and some people notice this more than others - the Zeiss view has a very slightly yellow colour cast. Again, not a fault, and, unless you are comparing two scopes side by side, mostly not noticeable. If you look through it next to a Swarovski, for instance, the Zeiss appears yellowish and "warm", the Swaro bluish and "cold".

Other things you should do with any optic:

a) Directly inspect all lens surfaces for any oddities or unevenness to the coatings or tiny bubbles, scratches or marks of any kind. Look also at the inner lens surfaces as best you can. Try this in varying lights and at different angles of view.

b) Look through the scope at minimum magnification at a blank wall or empty sky (it doesn't matter at all about focus for this test). Can you see any tiny bubbles, grease, smears, hairs or dirt anywhere in the field of view? Send it back!

c) Zoom to full magnification and focus in an out - again, any dirt, grease, smears, particles or bubbles? Send it back!

d) Any roughness in zooming and focusing? Bear in mind the focus will be stiffer when new, but eases with use. By the way, I find myself only ever using the "fine" focus control - you soon come to get used to it, and it really is a delightful focusing mechanism. Keep an eye on this if you feel roughness - but it will almost certainly soon wear off. If it doesn't improve, get in touch with the dealer.

Apart from that, someone here will post details of the definitive 'star test', I am sure. You've got a fantastic, top-notch scope on its way to you. You're going to have a good deal of enjoyment and pleasure using it. Do post back details of some of your experiences.

Ashu said:

Today I ordered Zeiss 85TFL from the same dealer. Could you suggest some simpe tests to find out the optical quality of the scope. It will be my first scope and I don't have any experience in testing optical instruments.
There are so many tests, resolution charts, opinions and counter-opinions available on the web that it's confusing.

Click to expand...

Hi Ashu,

I really understand the problem you´re in. I think the best you can do is comparing your scope with other scopes of your birding friends side by side and viewing at the same objects. You need this comparing strategy because there is no other reference you can go for. Take a look at brightness, contrast (viewing on dark objects how much details are you able to see?), resolution (e.g. dollar bill, newspaper - but take always the same ting for this test and always in the same distance). The star test mentioned here is quite easy done. When there is a clear night sky outside take your scope and have a look at a bright star near to zenith. The star shouldn´t show any astigmatisms. It should be look like a pinpoint with all magnifications. It is possible that you have to refocus if you doing this but this is quite normal.

I hope your confusion about all the opinions will soon disappear and much joy in using your new scope will follow!

Regards

Steve

brownie said:

Mate you had better be careful. I looked up the Zeiss webbsite for tech details for filtering my Zeiss 85.Guess what.the catch is that thread pitch is 1mm not the standard .75mm photographic type filter thread pitch.This means the thread although correct diameter,will be too fine to fit this lense.BEWARE...DONT FORCE IT.i HAVENT BEEN ABLE TO SOURCE A 86mm 1mm PITCH FILTER ANYWHERE>>>>>>>good luck BROWNIE

Click to expand...

I've been researching the filter thread issue as well and it appear that there are regular thread filters (I'm assuming that is the .75mm thread) and coarse thread filters (presumably 1mm thread). The designations for them at Focus camera seem to be 86mm or 86c since a lot of their large filters are labled "NOT 86c". Has anyone found a filter that fit the Zeiss properly and didn't degrade the image? Was it 86mm or 86c? Thanks! - Mary

marymac said:

I've been researching the filter thread issue as well and it appear that there are regular thread filters (I'm assuming that is the .75mm thread) and coarse thread filters (presumably 1mm thread). The designations for them at Focus camera seem to be 86mm or 86c since a lot of their large filters are labled "NOT 86c". Has anyone found a filter that fit the Zeiss properly and didn't degrade the image? Was it 86mm or 86c? Thanks! - Mary

Click to expand...

Mary,

I used a M86 UV/Skylight filter from B+W with my 85 Diascope. I don´t know what 86c is but I guess this filter has a diameter of 86 mm. I wasn´t very satisfied with that filter because I had the impression that it degraded the image slightly. Now this problem has gone because I let the filter fall down from a height of about 40 cm at a timber flooring. The glass broke into 1000 pieces. These filters seem to be very damageable so take care of them.

Regards

Steve

hinnark said:

Mary,

I used a M86 UV/Skylight filter from B+W with my 85 Diascope. I don´t know what 86c is but I guess this filter has a diameter of 86 mm. I wasn´t very satisfied with that filter because I had the impression that it degraded the image slightly. Now this problem has gone because I let the filter fall down from a height of about 40 cm at a timber flooring. The glass broke into 1000 pieces. These filters seem to be very damageable so take care of them.

Regards

Steve

Click to expand...

Thanks Steve -

I went ahead and ordered the Tiffen Skylight 1A 86c from B&H in NY and it fits the Zeiss perfectly! As I thought, the 86mm filters have a .75 thread pitch and the 86c filter has 1mm thread pitch which the Zeiss requires. Happily it doesn't seem to degrade the image quality at all. Very nice.

Also, just wanted to say that I received my new scope (green) from Highland Gear and would like to compliment them on their customer service. They mistakenly shipped me the silver scope first and when I told them of the mistake they overnighted me the correct one and paid for the return of the silver. Great! And best of all the scope looks great optically. I've got a friend's Swarovski ATS80 (not HD) here and the Zeiss is definitely sharper and brighter. I'll try to do a star test this weekend since I'm going camping.

Thank you to everyone on this forum (especially Scampo!) for their comments here and offline that helped me pick the Zeiss. It's a wonder! - Mary

marymac said:

Thank you to everyone on this forum (especially Scampo!) for their comments here and offline that helped me pick the Zeiss. It's a wonder! - Mary

Click to expand...

Thanks to you, too, Mary, for your kind words. I'm glad you agree with my own assessment of this amazing scope.

My Zeiss 85T*FL scope arrived yesterday. It was missing adapter for mounting it on tripod, but it was shipped promptly by the Zeiss customer support when I told them. When I looked through the scope I found that eye-piece has a black hair trapped inside it near the edge. It is visible at 20X magnification but goes out of view above 50X magnification. Zeiss dealer (Highland Gear) is going to ship a new eye-piece.
It seems Zeiss QA is somewhat lacking and I am little bit worried about the optical quality of the scope. I would like to test it exhaustively. I would like to know what tests should I do. For resolution test using dollar bill, till what distance it should be able to resolve the fine lines at each magnification. How to check for chromatic aberration, colour fidelity, collimation, astigmatism etc ?
How to use EIA1956 and USAF1951 resolution chart? I have downloaded them from internet but I could not find correct method of using it, like on what size of paper and how big it should be printed; how far it should be kept from the scope for a particular magnifination. What should the resolution capability of the Zeiss 85mm scope etc. etc. I will greatly appreciate help on this topic.

scampo said:

a) Directly inspect all lens surfaces for any oddities or unevenness to the coatings or tiny bubbles, scratches or marks of any kind. Look also at the inner lens surfaces as best you can. Try this in varying lights and at different angles of view.

b) Look through the scope at minimum magnification at a blank wall or empty sky (it doesn't matter at all about focus for this test). Can you see any tiny bubbles, grease, smears, hairs or dirt anywhere in the field of view? Send it back!

c) Zoom to full magnification and focus in an out - again, any dirt, grease, smears, particles or bubbles? Send it back!

Do post back details of some of your experiences.

Click to expand...

Ashu said:

My Zeiss 85T*FL scope arrived yesterday. It was missing adapter for mounting it on tripod, but it was shipped promptly by the Zeiss customer support when I told them. When I looked through the scope I found that eye-piece has a black hair trapped inside it near the edge.

Click to expand...

That is a real disappointment. Perhaps Zeiss in Germany need to sort out their QC if their good name is not to diminish? That said, I think you'll find Zeiss will resolve any problems at all that you have with the scope both promptly and very courteously.

I cannot help you with all of those tests, though. What I was able to do was test my scope for long periods alongside a Swarovski and a Nikon in all kinds of conditions. The Zeiss invariably at least matched them both using all the tests I wanted to try and, at maximum magnification, I think the Zeiss is a winner owing to its very usefully bright image. Bear in mind that the zoom eyepiece offers a uniquely wide field of view and, because of this, the view at the outer periphery is not meant to be entirely sharp.

Ashu said:

How to use EIA1956 and USAF1951 resolution chart? I have downloaded them from internet but I could not find correct method of using it, like on what size of paper and how big it should be printed; how far it should be kept from the scope for a particular magnifination. What should the resolution capability of the Zeiss 85mm scope etc. etc. I will greatly appreciate help on this topic.

Click to expand...

A star test at 60X is the easiest way to tell if your scope has one or more of the usual defects (astigmatism, miscollimation or pinched optics). This is not the sort of exhaustive star test done at 200X to precisely analyze wave front error. The defects you're looking for are pretty easy to see. Still, if you've never done it a star test can be a little tricky. My friend's Diascope that I described earlier in the thread had all three of the defects listed above so the diffraction pattern in his scope looked very strange indeed. If you go back through this thread you should find the information you need to get started. The thread "Zeiss scope repair" also has info on star testing. Let us know what you see.

Try the star test first. A scope that shows no serious defects in a star test is virtually certain to have good resolution.