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Fond Memories: 17 Years with a Zeiss Dialyt 10x40B GAT* (1 Viewer)

Troubador

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This is a look back at some of my memories of using a pair of Zeiss Dialyts but first, an explanation of how I came to acquire the Dialyts.

My first binoculars were a pair of 1971 Swift Audubons which turned out to be totally unsuited to British weather, fogging up regularly and needing to be returned to the importer for cleaning. The biggest problem was the size of these and the Swift Saratogas that Troubadoris was using. Our transport was a Honda motorcycle equipped with pannier boxes for holiday luggage and the Swifts took up a huge percentage of the available volume so they had to go. We were tempted by the compact roof prism models from Zeiss and Leitz, and over the next 5 years I had two leatherette-covered Dialyt 10x40Bs, and a Leitz Trinovid 10x40B which developed too much free play in the focus. This put me off Leitz so I returned to Zeiss and replaced them with the subject of this reminiscence, a Zeiss Dialyt 10x40B GAT*.

The 10x40s were with me from 1986 to 2003 and captured many terrific wildlife observations. There was the male Dotterel and its chicks on top of a Cairngorm mountain who lifted one wing to preen underneath it and caused his three chicks to try to copy him. Later there was a Golden Eagle carrying a hare over Glen Feshie, a flock of 32 Red-billed Choughs on the Isle of Islay, our first Sea Eagle over Loch Eyenort and 8 Minke Whales from the ferry on the way to North Uist, and 101 encounters with European Otters in Hebridean Seas including a unique sighting of a mother and cub.

This sighting took place on the north-west coast of the Scottish mainland where we were overlooking a large sea-loch when we heard a weird faint squeaking coming from somewhere below us. At first we looked for a possible bird as the origin, but nothing was near enough so we moved closer to the cliff edge and looked straight down and were astonished to see a mother Otter holding a cub by the scruff of its neck with her teeth, and swimming strongly into the inner part of the sea loch only a few metres off-shore. We have seen many mother Otters with very small cubs before and since this incident but have never seen them being moved by the mother in this manner. It is often the case that the natal holt (where mothers give birth and where they look after the cub until it is ready to go to water for the first time) is some distance from the area of sea and shore that is the mother’s territory, and maybe the mother was taking her cub to a holt with better access to her foraging grounds

For our first White-tailed Sea-Eagle we were hiking across a hill-top on our way to a narrow sea-channel to do some rock-pooling when we paused to catch our breath and gaze at the amazing landscape below us, with the huge expanse of Loch Eyenort backed by South Uist’s biggest hills. To the north, we saw a huge bird, gliding towards us and as it glided lower and closer, we looked at each other in amazement as the full extent of this bird’s wingspan became apparent. It glided past us at a lower altitude than us, so that we were looking down on it. Those who wrote that Sea-Eagles have such huge wings that they look like flying barn doors were not exaggerating. Even the ‘fingers’ at the tips of its wings looked enormous and its comparatively small tail gave it a very different outline from Golden Eagle.

I took them on business trips all over Europe as well as to South Africa and Zimbabwe. In Zimbabwe I stayed at the Victoria Falls Hotel and went on a boat trip on the River Zambezi, up-river of the Falls, and visited an island there where the Dialyts gave me great views of hundreds of Egrets and Cormorants. On the opposite bank, a 100 metres downstream, I saw 3 Crocodiles lazing on some mud, and one of them lifted its head, slithered down the mud into the river then swam lazily towards us. It rounded the tip of the island where we were standing and floated stationary, with its eyes above the water line. Our ranger said the Croc’ knew we didn’t belong on the island and that we would probably make our way back to the mainland and it was hoping to grab one of us if the opportunity arose. We disappointed it by getting back into our boat and powering away.

It was during these Dialyt-years that I learned the basics about Hebridean Otters:

They forage at all heights of tide but more frequently at and near low tide. This reduces the time and energy spent going down from the surface and back up again and maximises time among the sea-weed banks and rocks where they try to ambush fish and crabs.

An average foraging dive in Hebridean waters takes around 15 seconds despite the fact that a spooked Otter can stay submerged for a lot longer than this.

Often, when returning to the surface after a dive, their momentum will propel them up to half their body length vertically out of the water. We call this ‘periscoping’ and seals never do this.

Sunlight will often glint off the smooth skin of a seal but this is a very rare occurrence with fur-covered Otters. This can be very useful if all you see in the far distance is a vague shape half-hidden by choppy waters and you are unsure if it is a Seal or an Otter.

Otters don’t have blubber insulation like seals so they need to regularly come out of the sea to warm up and they carry a fish with them to eat (often an extra-large one) and so pay-back the energy used in swimming away from and then returning to, their foraging site.

Otters forage by searching places fish and crabs hide among sea-weeds and stones so they move steadily through their chosen foraging area and rarely reverse their direction of travel as swimming among sites already visited would be a wasteful use of energy.

Otters need to regularly wash the salt from their fur to maintain its insulation properties and during these years we began to learn how to recognise these washing and drying sites.

Otters vary enormously in their reactions to the presence of humans. Some get used to this while others submerge and disappear at the first sight of a distant human. It is imperative not to disturb any foraging Otter as they are on a knife-edge balancing the need to get food to not only power their muscles when foraging, but also to maintain their body temperature in the sea and during the night. Maintaining body temperature, especially in winter, isn’t just about staying comfortable, it is about staying alive. This is doubly important for nursing mothers who also need successful foraging to produce milk to not only grow their cub but keep it warm too.

It was a result of the many such wonderful observations that I came to have such a fondness and respect for the Zeiss brand. The Dialyts weren’t perfect though. Their weakness (apart from the fact that my unit wasn’t phase corrected) was really that the objective lenses moved to achieve the focus, and as they moved in and out they naturally pumped air in and out of the internal volume. They never fogged up internally, but there were two consequences from this design. The most annoying was that a thin film of grease built around the edge of the objective mounts and on the sides of the optical tubes over which the objectives traversed. Using a brush to remove particles from the objectives was fraught with the risk of the brush picking up some lubricant and then painting it all over the objectives. If this happened, and it did, getting the grease off was an irritating and time-consuming ritual. In addition, and this is more of a curiosity than a problem, the pressure inside the bino, which the moving objectives had to overcome, was somewhat variable depending on how gas-tight the seal was around the objectives and I guess this varied according to how much grease built up around there. It was most noticeable when flying in an airliner when the variations in cabin pressure made themselves known by variations in effort needed to move the focus wheel. I especially noticed this when flying to South Africa on a 12 hour flight over the Atlantic when the plane turned east and I was trying to get a look at Namibia.

Although I was fond of the Dialyts I gradually became aware of two of the downsides to 10x magnification and that is the reduced depth of field and field of view compared with 8x, which is what Troubadoris had always used. She would often see things in the field of view of her Leitz Trinovid 8x40s that were either out of sight of my Dialyts or simply out of focus. This was frustrating but it taught me that more magnification did not always mean ‘seeing more’. Plus there was the discovery that the more we visited the west of Scotland (which had won over our hearts) and were exposed to weather systems drifting in off the Atlantic, the more I had to deal with strong gusting winds creating bino-shake which clearly didn’t affect Troubadoris as much with her 8x Leitzes.

So when I picked up a new Swarovski EL 8.5x42 WB in 2003 I was immediately attracted by its optical quality (it was phase corrected and my Dialyt wasn’t) and its field of view of 130m compared with the Zeiss’s 110m. Plus I have to admit that contemplating the step from 10x to 8.5x wasn’t quite as daunting as all the way down to 8x. I loved the Swarovski but was dismayed when after only a year the focus began to develop free play (backlash) and tight spots. Returning it to Absam for repair resulted in an improvement but not a return to the quality of focus that had been present when I bought it. Disappointed with Swarovski I was delighted when Zeiss introduced the Victory FLs and I bought an 8x42 that served me well for the next 9 years.

If any of you has a Dialyt 10x40 BGAT* with serial number 1894514 then you have the one that used to be mine! It has been fun looking back over some of the many memories the Dialyts gave me, and I hope you have enjoyed them too.

Stay safe, everybody, and Happy Holidays!

Lee Dialyt 10x40.jpg
 

CharleyBird

Well-known member
Very enjoyable read. Eagles are always quite a sight. I've never seen an otter in the wild, but there is/was an otter farm on the A66 where you could go see dozens.

And just to tempt you, it might even be yours...

Edited to add, they have otters at Rye Meads RSPB, and when I asked about them, one of the voluteers said she'd never seen one in over a decade working there. You are lucky watching them this way
 
Lovely homage Lee! I really enjoyed reading your process of discovery with the otters (and how viewing them through the binoculars made those insights possible). My wife and I fondly remember our adventure on the West Highland Way, and the many wonderful wildlife sightings it afforded us. We were absolutely tickled by your most common birds (the robin! the corvids!). We found a Collins guide in a second hand store in Milngavie along with a pocket wildflower guide. Our first day on the WHW it took us at least a few hours to make it through Mugdock Wood because we had to stop and watch every tit and creeper. I imagine the other walkers must have been thinking "Those folks aren't going to make it" as they blew past us. I believe it was April and the smell of gorse in the air was intoxicating. Our number one conclusion as we left Fort William at the end of our walk: We've got to come back. Number two: We're not sharing one set of binoculars next time!

Thanks for sharing your stories,
~Stefan
 

NDhunter

Experienced observer
United States
Lee:
That was very interesting, both about the wildlife and the binoculars.
I enjoyed the part of how the mother otter moved her young one. Many of us have seen a mother cat move her
kittens the same way. Be sure not to get in the way...

Jerry
 

Troubador

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Thank you Charley, Stefan and Jerry. It was fun going back over my old records and remembering........
Lee
 

Troubador

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And just to tempt you, it might even be yours...
Hi Charley, This Dialyt is certainly from the right era. The eyecups don't look as though they have been folded to accommodate a spectacle-wearer but they might have been changed. Unfortunately In-Focus don't mention the serial number......

About the 'Otter farm' off the A66. I have never heard of Otters being 'farmed' and doubt if it is legal so perhaps this farm was breeding Mink. I have drive over the A66 from Scotch Corner to Penrith and in the reverse direction probably more than 100 times for business as well as holidays and never saw a Mink farm. Fur farming was banned in the UK in 2000.

Lee
 

Dutchbirder64

Well-known member
Lee, nice write up. I still have my 10x40 B GAT that I bought new in 1986. I still use it and had some good birdwatching today. I have a Swarovski NL Pure 10x42 and it is far better optical but the Zeiss will stay to be my friend. Best rare birds seen with it. Buff breasted paradise kingfisher in Australia and Smiths longspur in Alaska.
 

Troubador

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Thanks Andy. Maljunolo and Dutch 64. I have to confess most of the time I think of my binos as companions rather than optical curiosities to be scientifically analysed.

Happy Holidays to all.

Lee
 

CharleyBird

Well-known member

Troubador, searching I found it as part of the Otter Trust. But basically it's a converted farm, up on the high moors on the side of the A66, there was a barn with lots of otters, and then you can walk down a track to see...more otters. Easily missed, I remember we were looking for it heading west from Barnard Castle and my Dad still drove straight past the turning. Mind you this was years ago.
Then if you want to see ostrich and alpacca, a few miles to the east also on the A66 but close to the A1, there is Mainsgill Farm, where you can get a good meal and enjoy their extensive if pricey gift/farm shop.
 

Troubador

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Troubador, searching I found it as part of the Otter Trust. But basically it's a converted farm, up on the high moors on the side of the A66, there was a barn with lots of otters, and then you can walk down a track to see...more otters. Easily missed, I remember we were looking for it heading west from Barnard Castle and my Dad still drove straight past the turning. Mind you this was years ago.
Then if you want to see ostrich and alpacca, a few miles to the east also on the A66 but close to the A1, there is Mainsgill Farm, where you can get a good meal and enjoy their extensive if pricey gift/farm shop.
Thanks for taking the time to look this up Charley. I must confess I was too quick to let the word 'farm' create images of fur-farming in my head but I wasn't aware of the Otter Trust so many thanks for this. Yes we have seen the Alpaccas from the A66, they have been there a few years now haven't they? Troubadoris's brother has also stopped for a meal at Mainsgill Farm and recommended it so we might try it out sometime although we usually like to get north of the Scottish border before stopping to eat. Thanks again and Stay Safe.
Lee
 

Troubador

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Lee:
That was very interesting, both about the wildlife and the binoculars.
I enjoyed the part of how the mother otter moved her young one. Many of us have seen a mother cat move her
kittens the same way. Be sure not to get in the way...

Jerry
Jerry

Just for you I will say a bit more about young Otter cubs. When they first go to the sea they can float just fine but they can't swim well. We have seen one splashing water in all directions as it tried to swim while sticking its head under the water to see where its mother had gone. On the following day it could swim smoothly and without splashing but it couldn't dive. We have seen other cubs a bit further on in their development and they could dive a very very short distance under the water but almost immediately floated back to the surface. They couldn't actually get as deep as their mother but I am sure that within a day or two they learned.
And just like cats we have seen a mother Otter put its paw on the face of a cub that was annoying her and hold it down and we have seen cats do the same.

Lee
 

PennineBirder

Well-known member
Thanks for that write up- it brought back fond memories of my own Zeiss 10x40BT* leatherette version that I had all through the 1980s and 90s. What intrigues me now is that you hardly ever saw any birder using the Zeiss 8x30B model at that time considering how popular the 8x32 format is today. I wonder why?
 

Troubador

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Thanks for that write up- it brought back fond memories of my own Zeiss 10x40BT* leatherette version that I had all through the 1980s and 90s. What intrigues me now is that you hardly ever saw any birder using the Zeiss 8x30B model at that time considering how popular the 8x32 format is today. I wonder why?
Thats an excellent point. I don't remember seeing any 8x30B Dialyts at all. Maybe 30mm binos were not taken seriously back then. I certainly didn't. And as the UK population has grown with more folks over retirement age so has demand for compact and lighter instruments. Its a different world now.

Lee
 

CharleyBird

Well-known member
"Thanks for taking the time to look this up Charley. I must confess I was too quick to let the word 'farm' create images of fur-farming in my head but I wasn't aware of the Otter Trust so many thanks for this. Yes we have seen the Alpaccas from the A66, they have been there a few years now haven't they? Troubadoris's brother has also stopped for a meal at Mainsgill Farm and recommended it so we might try it out sometime although we usually like to get north of the Scottish border before stopping to eat. Thanks again and Stay Safe.
Lee"

Lee, my family in Durham have been going to Mainsgill for maybe 15 years. The gift shop is now an aladdins cave, last time I was there bought my sister a Scottish made tweed handbag, daughter a cashmere scarf, other daughter earrings, plus jam, cheese, gifts! Car park is large and busloads of people turn up, but the ostriches are great.
Our border collie woofed at the alpacas in the field briefly, but when he saw the ostriches in the barn he stopped and his expression was quizzical, an absolute treat.
The place is quite the opposite of the discreet Otter-trust-farm.

Best of the season to you
Andy
 

Maljunulo

Well-known member
My first "really good" binoculars were Nikon Venturer LX 10X42, purchased during or before 2001. they went everywhere with me until 2014, when I replaced them with a pair of EL SV 10X42, which went everywhere with me for six years, after which I gave the Nikons to my Other Half.

The Swarovski glasses will be sent to my #1 granddaughter after the first of the year, and the Nikons have been given to #2 granddaughter by Other Half.

I now have SF 8X32 as my primary binocular, and they will now go everywhere with me, so I have finally wandered into the Zeiss camp.

Words fail me in trying to describe the enjoyment I have had over the years from all of these glasses, and the memories are many, even as they are fading.

The SF are mind-boggling, and I am so glad that I have the eyesight to appreciate them, the means to afford them, and the leisure to enjoy them. After years of saying "I have never wished for a smaller image." I realize that I may have done better to choose 8X or 8.5X instead of 10X.

Life is a never-ending learning process. For me, after all the hand waving, literature citing, and specification quoting is over and done, what is really important is what you see. I have not previously seen images to rival those I see in the SF.

I hope everyone here has a good holiday season, and that 2021 will be an improvement for all.

Richard
 
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Patudo

Well-known member
There has been many a love letter written to the 10x40 Dialyt over the years, and not without cause. I suppose the relative lack of competition at the time helped, and yes, the birding binocular has been improved and refined since, but I still think Zeiss achieved something with its 10x40 - a combination of size and compactness with the 10x magnification and a focus that was neither too fast nor too slow - that made it a really good all-rounder (especially for its era). And for those who love binoculars in themselves, they are still a great looking binocular - clean and simple lines, compact yet well-proportioned, with the GA models clad in that iconic businesslike rubber armouring. Even though the 7x42 (P model) is the more desired of the two today, I feel it is this model that is (a very big claim I know, given all the great binoculars that have come from Jena, Oberkochen and Wetzlar) the classic of all the Zeiss classics. Just look at it, never mind handle it, and you can practically feel the Zeiss-ness.

Mine is the P model, the last, phase-coated version, and as a result the best performer optically. Like Troubador's I suppose they were my first "really serious" binocular and like Troubador I came to them after having used porros (in my case a Japanese 10x42 and an 8x30 Jenoptem). Being a fair weather birder then and now, I didn't have issues with weather, but I'd learned from using the old porros how much of a handicap having to remove my glasses to use the binoculars could be. The long eye relief of the Dialyt solved that issue, It was also (not unsurprisingly, as neither of the two porros I used would have matched Troubador's Swift Audubon) a better performer optically - in particular, more vivid colours and better contrast. After having used both 8x and 10x (and also 8.5x) I knew I liked the 10x magnification (something which has held true to this day - although I have more 8x and 7x, I'd say at least 50% of my viewing is with 10x). They seemed very well built then, and after having handled a good many more binoculars, I'd say they still do - the famous rubber armour is hard-wearing and the controls (hinge, focus, diopter) have remained smooth and positive. I must have been lucky with mine in that, although its focus wheel does not turn with the perfect blend of weight and delicacy one gets from say a Nikon EDG, I never experienced the play in the focus other users have reported.

Troubador's post made me realize (although he and others had mentioned it previously) something I hadn't noticed after all these years - the objectives move in and out when focusing! Maybe it's because mine are almost always focused for long distance (where the objectives are near the end of their travel), but I have fortunately been spared any issues with getting grease on the objectives. My main gripe with it (losing distant birds at the limit of binocular-assisted vision earlier than my brother would) is pretty esoteric and cannot really be blamed on the binocular. It's not my choice if targets have to be spotted and tracked at long distance, but in most situations is still a very functional and useful birding tool, although slightly (but noticeably, to my eyes) outperformed optically by today's sub-alphas like the Meostar, Conquest HD etc. Its compactness (which Troubador referred to) makes it great to take with you when travelling, and in sunnier climes I feel one of my other gripes (being somewhat finicky in terms of eye placement when scanning afar) seems to go away.

Like the guys in the other thread, I have more memorable moments with this binocular than any other. Besides many spectacular observations of peregrines hunting, two others stand out, both from abroad: a stunning view of a crimson sunbird that landed close by, and admiring a crested goshawk that flew up to a tree with prey. The detail that the 10x mag showed me on both birds, at those relatively close distances, was amazing - the intense red of the sunbird's plumage, the furious yellow of the accipiter's flashing eyes, the grey-brown sides of its neck, and the streaks and dapples of its underside. Funnily enough, the first otters I ever saw were also with these (although none of the fieldcraft Troubador describes was needed on my part, as the pair of smooth-coated otters hopped up to a landing not far from my observation point on the Singapore River waterfront!).

I wouldn't go so far as to say, as others have, that I would never sell mine. But I'd hate to be in a position where I needed the £350 or so that is all I could probably get for them so badly. If only Zeiss would do (or had done) with the non-P Dialyts as Swarovski used to do with their SLCs and upgrade these - even for an extra cost - with phase-coated prisms (ideally dielectric coated for that extra little amount of brightness), it wouldn't be a surprise if many more of these would still be in regular use today.

These two snapshots taken not far from where I saw the otters:
 

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