dalat
...
Thanks! :t:
-
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
50mm Zeiss SF --- When??! (1 Viewer)
- Thread starter Chosun Juan
- Start date
Thanks! :t:
james holdsworth
Consulting Biologist
Thanks for the information. It would be great if something like the Astro standard was universally used for bino testing too, so we could really compare all things equally.
NDhunter
Experienced observer
Jan, Thanks for the constructive input :t: I take it that the 50mm figure would be 50mm+ and include larger sizes, 52mm, 54mm, 56mm, 58mm, and the one 20x60 IS that gets sold every year! :-O
Perhaps our forum is populated by lots of ex-sawmillers, with 4 fingers left on each hand, and for whom a missing 20% is entirely inconsequential?! :-O :brains: o
-----------------------------------------------------------------------------------
View attachment 603384
As for the other "keyboard warriors", I've had an absolute gutful! :C :storm: ...... what's with all the thinly veiled ad hominem attacks?!¿
Jerry, I'd ask you to explain, but unless you've got a Doctorate in Business Administration, I'm probably not interested
Hermann, who are these forum heroes that you speak of? .... can I get an autograph? .... and does dennis know?? :king:
----------------------------------------------------------------------------
The disgusting performance on John Cantelo's "Ethics" thread, by Jerry, and stephen b (whose girl's blouse display over an Internet search term of all things! .... I'm still counting to 10 million before addressing that), does you guys no favours at all. If you want to look like a flock of short neck geese - fine. But do it somewhere else .....
Now, can we get back to the topic at hand with some constructive discussion? .......
Chosun :gh:
The picture of you and your Joey is just what I imagined. :gh:
I am wondering why you are picking on Zeiss, on what optics you think
they should bring to market.
The closest I've found for your wish list, is the Maven 9x45 B2, with
Abbe Koenig prisms should offer you enough light transmission, if your eyes are up to task.
I suspect it does not matter much, you won't be buying any of these,
just offering too much blather. If you need to know the definition, check
it out.
I appreciate those that post who actually use binoculars, and know what
they are talking about.
Jerry
Chosun Juan
Given to Fly
Bin, thanks for this interesting information :t:
I read up on the Sony advancements and they certainly sound promising for better performing, lower cost aspherics. I would be surprised if other industry players didn't have something similar, or at least on the boil. Such things will help bring a high performing lightweight 50mm to market without unduly increasing the physical size too much, as this starts to become an issue too at a certain point.
Chosun :gh:
Hi Chosun,
Zeiss were producing machine aspherics in the 1930s using machines developed by others before them.
But obviously Sony's machine is much more capable, although I wonder how it copes with wear and how do you test the finished optical surface?
Astro testing on the stars only tests surface accuracy, alignment and aberrations.
For contrast with binoculars one needs terrestrial testing for contrast and colour rendition.
Planetary observations with large telescopes tests contrast well and also ones eyes. But planets are too small for binoculars.
Faint contrast detail on Saturn always eluded my eyes, although others saw it well.
Similarly, some see detail on Neptune and Uranus, others never.
I never saw detail on Jupiter's moons, others do.
Planetary testing is more severe than star testing.
Zeiss were producing machine aspherics in the 1930s using machines developed by others before them.
But obviously Sony's machine is much more capable, although I wonder how it copes with wear and how do you test the finished optical surface?
Astro testing on the stars only tests surface accuracy, alignment and aberrations.
For contrast with binoculars one needs terrestrial testing for contrast and colour rendition.
Planetary observations with large telescopes tests contrast well and also ones eyes. But planets are too small for binoculars.
Faint contrast detail on Saturn always eluded my eyes, although others saw it well.
Similarly, some see detail on Neptune and Uranus, others never.
I never saw detail on Jupiter's moons, others do.
Planetary testing is more severe than star testing.
Hermann
Well-known member
In binoculars - yes. But AFAIK Kowa uses a calcium fluorite lens in their top-of-the-line scopes (883, 884) and started doing so quite a few years ago in the TSN-3 and the TSN-4.
BTW, I didn't hear of any problems with the calcium fluorite lenses in these scopes.
Hermann
Last edited:
Early Canon 300mm f/2.8 lenses had the crystal element fail badly, but they got better.
The instruments have to carefully designed also as I think moisture can damage the crystal.
I suppose there are crystal elements in high end astro scopes.
If I look at such instruments I carefully examine them.
I am not sure that I would buy such second hand optics.
Even high end exotic glass is very delicate. Top end lenses lenses containing such elements have to be multi coated as soon as the element is made as they begin to tarnish straight away.
Yet there are lenses with simple glass which look good after 150 years.
The instruments have to carefully designed also as I think moisture can damage the crystal.
I suppose there are crystal elements in high end astro scopes.
If I look at such instruments I carefully examine them.
I am not sure that I would buy such second hand optics.
Even high end exotic glass is very delicate. Top end lenses lenses containing such elements have to be multi coated as soon as the element is made as they begin to tarnish straight away.
Yet there are lenses with simple glass which look good after 150 years.
Last edited:
Hermann
Well-known member
Like I said - no problems with the Kowa scopes. Never heard of any mishaps. Calcium fluorite lenses are usually deployed as the seceond element in the objective, and thus protected to some extent from the environment. In addition the coatings provide some protection as well. Moisture isn't that much of a problem, I think, but I can't find the source where I found that right now.
The benefits of using calcium fluorite lenses are pretty obvious to anyone who knows the Kowa scopes. Their optical quality is quite something.
Hermann
Last edited:
I hope that Gijs doesn't mind.
But
Dr Gijs van Ginkel
Investigation of top quality telescopes.
2009.
He confirms, as I well know, that calcium fluorite is affected by humid air.
That is why such elements, not only have to coated and placed in between other elements, but also sealed properly.
If badly treated or used by the seaside, I wouldn't buy an old instrument containing calcium fluoride and I would check any instrument with exotic glass.
As an aside my 52cm Newtonian mirror lost all its new coating one week from new because I backed my classic Saab without catalyser into the garage, where the exhaust gases went into the scope bottom end where the mirror was situated.
One week..
But
Dr Gijs van Ginkel
Investigation of top quality telescopes.
2009.
He confirms, as I well know, that calcium fluorite is affected by humid air.
That is why such elements, not only have to coated and placed in between other elements, but also sealed properly.
If badly treated or used by the seaside, I wouldn't buy an old instrument containing calcium fluoride and I would check any instrument with exotic glass.
As an aside my 52cm Newtonian mirror lost all its new coating one week from new because I backed my classic Saab without catalyser into the garage, where the exhaust gases went into the scope bottom end where the mirror was situated.
One week..
Hermann
Well-known member
I've seen dozens of Kowas over the years. I never saw one that had any problems with the calcium fluorite lens. Not one.
Taking into account the differences between a waterproof spotting scope and a Newtonian .... what precisely is your point?
Hermann
The point is that the protection must be good enough to last a long time, hopefully 50 years.
But the underlying problems are there.
Kowa obviously put a great deal of effort into protection as do many top makers.
I have personally seen and handled hundreds of failed lenses and binoculars. Not so many scopes as they are fairly simple.
Usually it is fungus. Also moisture internal coating lenses and prisms.
Olympus lenses fungus numerous.
Nikon lenses very dirty inside.
Coating failure.
Balsam failure. Zeiss Ikon lenses etc.
Mirror tarnish, say Nikon 500mm f/5 mirror lens and others.
Minolta 500mm f/8 mirror lens.
Thorium elements brown low transmission.
Northumberland 12 inch refractor devitrified after 100 plus years. New objective made.
Scratches allowing fungus to creep around front element of binoculars.
Small insects inside lenses of binoculars and photo lenses and viewfinders.
Spiders running around inside optics.
The fact is that buying secondhand you must inspect carefully.
I would think that in Hong Kong lenses are still routinely stripped for removing fungus.
TTH lenses are made with disassembly in mind.
Some people deliberately sell secondhand optics with these faults after grabbing money first.
I suppose Halloween is the time for scary stories.
Oh and a brand new WATERPROOF Chinese binocular with internal fungus.
And I got a Zeiss top end binocular sold as new and sent to the U.K. This had fine scratches around the eyepiece rear elements. This was not as described at all. But life is too short to bother about it.
O.K.
I wanted an as new Classic Zeiss binocular.
An immaculate U.K. source got me one supposedly from a retail shop in Zeiss's homeland where it had supposedly been sitting on the shelf..
I paid the full price.
It was not new as described.
Now, this was forgotten and just remembered, but the idea that everything in optics is always perfect is far from the truth.
Nearly all my optics have come from the U.K. but occasionally I have stepped outside.
I love optics and have had great pleasure from them. But sometimes it has a downside, but not too often.
And one learns as one gets older to be careful if possible.
Peace.
But the underlying problems are there.
Kowa obviously put a great deal of effort into protection as do many top makers.
I have personally seen and handled hundreds of failed lenses and binoculars. Not so many scopes as they are fairly simple.
Usually it is fungus. Also moisture internal coating lenses and prisms.
Olympus lenses fungus numerous.
Nikon lenses very dirty inside.
Coating failure.
Balsam failure. Zeiss Ikon lenses etc.
Mirror tarnish, say Nikon 500mm f/5 mirror lens and others.
Minolta 500mm f/8 mirror lens.
Thorium elements brown low transmission.
Northumberland 12 inch refractor devitrified after 100 plus years. New objective made.
Scratches allowing fungus to creep around front element of binoculars.
Small insects inside lenses of binoculars and photo lenses and viewfinders.
Spiders running around inside optics.
The fact is that buying secondhand you must inspect carefully.
I would think that in Hong Kong lenses are still routinely stripped for removing fungus.
TTH lenses are made with disassembly in mind.
Some people deliberately sell secondhand optics with these faults after grabbing money first.
I suppose Halloween is the time for scary stories.
Oh and a brand new WATERPROOF Chinese binocular with internal fungus.
And I got a Zeiss top end binocular sold as new and sent to the U.K. This had fine scratches around the eyepiece rear elements. This was not as described at all. But life is too short to bother about it.
O.K.
I wanted an as new Classic Zeiss binocular.
An immaculate U.K. source got me one supposedly from a retail shop in Zeiss's homeland where it had supposedly been sitting on the shelf..
I paid the full price.
It was not new as described.
Now, this was forgotten and just remembered, but the idea that everything in optics is always perfect is far from the truth.
Nearly all my optics have come from the U.K. but occasionally I have stepped outside.
I love optics and have had great pleasure from them. But sometimes it has a downside, but not too often.
And one learns as one gets older to be careful if possible.
Peace.
Last edited:
NDhunter
Experienced observer
Chosun:
I have been thinking about your demands upon Zeiss, and have wondered about your
experience with 10x50 binoculars.
You have to walk before you run, and so tell us your experience with this size and
why your request.
I have some experience with some very nice 10x50 binoculars, and this one is my
latest acquisition.
A Bushnell, and it offers a nice center view and the focuser is tight and sweet.
Report back when you gain a little more experience, with 50mm optics.
Jerry
I have been thinking about your demands upon Zeiss, and have wondered about your
experience with 10x50 binoculars.
You have to walk before you run, and so tell us your experience with this size and
why your request.
I have some experience with some very nice 10x50 binoculars, and this one is my
latest acquisition.
A Bushnell, and it offers a nice center view and the focuser is tight and sweet.
Report back when you gain a little more experience, with 50mm optics.
Jerry
Attachments
Last edited:
Chosun Juan
Given to Fly
Jeez Jerry, give it a rest - you're starting to drive really slowly in the ultrafast lane again :storm:
If you had the EI to get outside of your own little world, you might be able to see and comprehend what your behaviour looks like ...... I certainly wouldn't want it on the permanent cyber record if it was mine - you may be different. Perhaps if one of your "buddies" cares enough, they could point you in the right direction.
I'm well and truly on the record as saying I don't like the "wings out" handling of just about all Porro's - including the 10x50 given to me by my grandfather ...... :smoke:
The 'handling' of the Swaro 10x50 SV on the other hand, I find most satisfactory, apart from the weight, and dinky little, coarse, pedestrian focuser ...... :cat:
I showed my 3 year old niece the picture of your Bushnell Omega - she was most impressed by the bright flashes of yellow colour ..... o
As we're considering the other end of town, I will leave you to attend to other matters ...... I think I can hear your name being called ........
:hippy: Chosun :gh:
If you had the EI to get outside of your own little world, you might be able to see and comprehend what your behaviour looks like ...... I certainly wouldn't want it on the permanent cyber record if it was mine - you may be different. Perhaps if one of your "buddies" cares enough, they could point you in the right direction.
I'm well and truly on the record as saying I don't like the "wings out" handling of just about all Porro's - including the 10x50 given to me by my grandfather ...... :smoke:
The 'handling' of the Swaro 10x50 SV on the other hand, I find most satisfactory, apart from the weight, and dinky little, coarse, pedestrian focuser ...... :cat:
I showed my 3 year old niece the picture of your Bushnell Omega - she was most impressed by the bright flashes of yellow colour ..... o
As we're considering the other end of town, I will leave you to attend to other matters ...... I think I can hear your name being called ........
:hippy: Chosun :gh:
Last edited:
I used to have one of the early black case Canon FD ssc Fluorite 300 f2.8 lenses. It had been converted to motion picture use in the late 1970s. As an ex-rental lens it had been around the world numerous times on films.
The rental companies regularly strip down and service their stock. Once that ceased the fluorite quite quickly developed blooming.
Try as I might I couldn't undo the front ring so sold it off cheap on ebay. In retrospect I should of smashed the front element and kept the fluorite crystal as a curio !
The later internal focus white FD lenses like this one are still in wide spread use in the film industry
http://global.canon/en/c-museum/product/nfd226.html
This lens with fluorite and quartz elements, but no glass, has been into space numerous times with NASA
http://www.hasselbladhistorical.eu/pdf/lds/CF105.pdf
After doing a bit of research I've come to the conclusion that current Nikkors that have the FL designation don't have calcium fluorite elements. They are fluorite glass. A material that is easier to work with and substantially cheaper.
Last edited:
Thank you very much for the interesting information, maico.
I was offered 6 Zoomar 180mm f/1.3 motion picture lenses at about £650 a time many years ago.
I wasn't interested in even one.
But he had an incomplete one at £25 in its trunk, which I bought.
I managed to get all sorts of adaptors from someone else for next to nothing for Contarex etc etc and Minolta.
I put it on my Minolta and although the ring was missing I could operate it with say a pencil.
Although it was a half frame 35mm camera lens, it worked absolutely fine at full aperture. The field was curved, but flat on half frame or movie format. On full frame 35mm the edges were soft but most of centre sharp at f/1.3.
It was fast, although I can't say it was easy to hand hold. I usually balanced it on something.
The seller was not happy when I showed him the photos I took with what he thought was a non functioning lens.
They also made a 240mm f/1.2 Zoomar/Kilfitt, I think, for medium format. It is big.
There were Kilfitt adaptors I think for all sorts of movie and film cameras.
I have, though, seen much bigger lenses such as 14 inch f/0.75 weighing I think 350 lbs. Mounted on a truck.
The top makers have developed strategies for using Calcium fluorite, probably by coating straight away, although coating is probably very difficult in this case. Then sealing the element in so no moisture gets in.
By controlling things carefully they probably don't get many failures now, although they probably did early on.
I would not choose a crystal lens scope if I was in a tropical jungle environment. Eventually nature has its way and moisture gets in.
But I take the point that most Kowa scopes are fine, although I suppose any problems are immediately dealt with by Kowa, a top maker of exotic optics.
P.S.
I think the calcium fluorite has problems with laser light and deep UV, but I don't know the details.
Quartz is used in things like some of the Questars, I think.
P.P.S.
Those early Canon 300mm f/2.8 were often sold off at £100 or less because of the serious degradation of the calcium fluorite element.
I was offered 6 Zoomar 180mm f/1.3 motion picture lenses at about £650 a time many years ago.
I wasn't interested in even one.
But he had an incomplete one at £25 in its trunk, which I bought.
I managed to get all sorts of adaptors from someone else for next to nothing for Contarex etc etc and Minolta.
I put it on my Minolta and although the ring was missing I could operate it with say a pencil.
Although it was a half frame 35mm camera lens, it worked absolutely fine at full aperture. The field was curved, but flat on half frame or movie format. On full frame 35mm the edges were soft but most of centre sharp at f/1.3.
It was fast, although I can't say it was easy to hand hold. I usually balanced it on something.
The seller was not happy when I showed him the photos I took with what he thought was a non functioning lens.
They also made a 240mm f/1.2 Zoomar/Kilfitt, I think, for medium format. It is big.
There were Kilfitt adaptors I think for all sorts of movie and film cameras.
I have, though, seen much bigger lenses such as 14 inch f/0.75 weighing I think 350 lbs. Mounted on a truck.
The top makers have developed strategies for using Calcium fluorite, probably by coating straight away, although coating is probably very difficult in this case. Then sealing the element in so no moisture gets in.
By controlling things carefully they probably don't get many failures now, although they probably did early on.
I would not choose a crystal lens scope if I was in a tropical jungle environment. Eventually nature has its way and moisture gets in.
But I take the point that most Kowa scopes are fine, although I suppose any problems are immediately dealt with by Kowa, a top maker of exotic optics.
P.S.
I think the calcium fluorite has problems with laser light and deep UV, but I don't know the details.
Quartz is used in things like some of the Questars, I think.
P.P.S.
Those early Canon 300mm f/2.8 were often sold off at £100 or less because of the serious degradation of the calcium fluorite element.
Last edited:
Chosun Juan
Given to Fly
Jeez ! Time flies ! I can't believe it has been up to ~4 years or more since the 42mm SF's were released :brains:
And still we have no HT glass upgrades to the 32mm FL, nor the 42mm SF's. Also no hint even of 32mm SF's, nor 50mm SF's .....
What on earth have Zeiss been doing?! :h?:
The time has well and truly come for all of these to be on market - Now!
Leica has come out with the HT glass containing NoctiVid to wide acclaim, and even new upstart Tract are getting in on the act.
Time to put the foot down Zeiss !!
Chosun :gh:
since the 42mm SF's were released :brains:And still we have no HT glass upgrades to the 32mm FL, nor the 42mm SF's. Also no hint even of 32mm SF's, nor 50mm SF's .....
What on earth have Zeiss been doing?! :h?:
The time has well and truly come for all of these to be on market - Now!
Leica has come out with the HT glass containing NoctiVid to wide acclaim, and even new upstart Tract are getting in on the act.
Time to put the foot down Zeiss !!
Chosun :gh:
Its a good question CJ and I know some bino dealers who would love to see this happen. What have Zeiss been doing? There are two answers to this. On the product side they have developed and launched an HT-based range finder bino and developed the constant-angle-of-view Harpia scope. On the organisation side things don't look rosy at all and must be having an impact on product development. It was reported late last year that 140 jobs were being lost at Wetzlar and 80 transferred to Oberkochen 340 kilometres away. It doesn't take much imagination to conclude that plenty of folks holding those 'transferred' jobs will not wish to leave their home town and will be jumping ship to take up jobs elsewhere. If the deficit between the number of jobs that are ending and the number 'transferring' is to be filled by Oberkochen personnel taking on dual-function jobs (ie doing Sports Optics work as well as work on other products) there wiil be time needed for retraining and reorganising. Customer Service is staying in Wetzlar.
I have been in 'restructuring' companies and as hard as a company might try there was always a severe impact on normal business activities. And of course public announcements like the one mentioned above by no means reveal all the internal goings-on that may have had impacts leading up to the momentous decision that was announced. It seems likely to me that the company has been struggling with the issues that led to this 'restructuring' announcement since Richard Schmidt left the company 4 years ago.
The Oberkochen site is immensely impressive in scale and with its facilities and the quality of the product they turn out so the long-term future of Zeiss Sports Optics looks good but between now and then it seems there will inevitably be disruption to all activities.
Lee
I have been in 'restructuring' companies and as hard as a company might try there was always a severe impact on normal business activities. And of course public announcements like the one mentioned above by no means reveal all the internal goings-on that may have had impacts leading up to the momentous decision that was announced. It seems likely to me that the company has been struggling with the issues that led to this 'restructuring' announcement since Richard Schmidt left the company 4 years ago.
The Oberkochen site is immensely impressive in scale and with its facilities and the quality of the product they turn out so the long-term future of Zeiss Sports Optics looks good but between now and then it seems there will inevitably be disruption to all activities.
Lee
Last edited:
etc
Well-known member
One item *is* wrong with Leica 10x50 and 8x50 and all other models - their diopters at infinity value is -4D. If you have myopia that exceeds that value and I have -5.25D, I cannot use any Leica devices without corrective devices.
If you have myopia less than -4D, you are OK. But for many, it is a big deal - we have to go to Zeiss/Swarovski to get between 6D and 8D overdrive past infinity. I do not want to use binoculars through eyeglasses, the view is compromised.
james holdsworth
Consulting Biologist
Jeez ! Time flies ! I can't believe it has been up to ~4 years or more
And still we have no HT glass upgrades to the 32mm FL, nor the 42mm SF's. Also no hint even of 32mm SF's, nor 50mm SF's .....
What on earth have Zeiss been doing?! :h?:
The time has well and truly come for all of these to be on market - Now!
Leica has come out with the HT glass containing NoctiVid to wide acclaim, and even new upstart Tract are getting in on the act.
Time to put the foot down Zeiss !!
Chosun :gh:
I thought you loved the one HT you looked through - why not just buy a pair and be happy?
