British v German rangefinders

Warship design and construction, terminology, navigation, hydrodynamics, stability, armor schemes, damage control, etc.
Christian VII.
Member
Posts: 80
Joined: Sat Jan 17, 2015 7:49 am

Re: British v German rangefinders

Postby Christian VII. » Thu Sep 17, 2015 10:02 am

The person on that website is mistaken, he brings no source to the table either :) According to most sources most German optical equipment was coated after 1938 (of which there is plenty of evidence), incl. most army & luftwaffe binocs as well as rifle telescopes - heck even perscription glasses. One way to see this is by looking for the letter T or, since far from all coated equipment bear this marking, simply by visually inspecting the lenses. Most importantly a lot of originally uncoated equipment made before 1936 was re-coated during the war, and the Germans didn't mark their coated rifle scopes at all for example. i.e. a lot of wartime coated optics, if not most, weren't marked at all.

Lots of coated originals for the KM, LW & WM available here: http://www.binoculars-cinecollectors.co ... k_p_4.html

As for the effect of the lens coatings, they really can't be understated (esp. in large complex optical equipment) as with the Zeiss hard coatings the light transmission was improved by over 80% pr. lens, and since most optical equipment used 4 or more lenses (large naval equipment used far more) this added up in the end. This is esp. true with the German use of multicoating, i.e. the coating of all lens surfaces.

Image

But you are right that there are other ways to combat this problem, one is simply to use a lower amount of lenses, but this limits you in other areas, such as magnification & FoV. Another method is by using bigger objective & occular lenses, something the Germans were already doing on top of using coatings, and the Japanese started doing the same in the 1920's.

This is probably also the reason why German & Japanese rangefinders featured so much higher a magnification performance, 50x on the German RF's, and 30x on the Japanese RF's on the Yamato. You needed better glass and/or coatings to achieve this whilst still maintaining an acceptable brightness of image.

Also regarding the Japanese optics, their optics industry was created with help of German advisors and technological support starting in 1917, and many new technologies were traded during WW2, incl. the use of Lanthanum as well as H (Helligkeit) glass. Some more information here:
http://www.referenceforbusiness.com/his ... ATION.html

Thus it is no surprise that Japanese optical equipment impressed the US, they were basically looking at German equipment, albeit uncoated.

PS: I remember reading that prior to the war the British admiralty was very concerned regarding the RN's inferior optical equipment in comparison to regular uncoated Zeiss binoculars. So much so that a competition was arranged with various British optics companies to come up with an equal piece of equipment. IIRC Barr & Stroud came closest, but with a much larger piece of equipment.

Christian VII.
Member
Posts: 80
Joined: Sat Jan 17, 2015 7:49 am

Re: British v German rangefinders

Postby Christian VII. » Thu Sep 17, 2015 11:08 am

dunmunro wrote:
Most German military optics were uncoated, as were most Allied Optics. This information is widely available, and all you have to do is look for it:

"Although some Zeiss Kriegsmarine 6X30’s did have coated optics, the German Army Dienstglas did not."
https://www.flickr.com/photos/binocwpg/7516684888

"1943 10 x 50 Dientsglass...
The BLC dientsglas uncoated model was produced in large quantities."
http://www.binoculars-cinecollectors.co ... 9_10x.html


The first pair is a Swarovski, an Austrian binocular taken into use by the German army. Swarovski didn't use any coatings. The flickr poster is wrong about Germany army Dienstglas not using coatings however, something your 2nd link proves as well.

The 2nd is pair of uncoated Dienstglas, but you only have to scroll down to find that the rest which are presented are mostly coated :)

In addition to that there are a wealth of original coated German army binocs on the same website.

As the website notes however many late war Dienstglas were only internally coated, probably due to knowing that the field conditions of a regular grunt who didn't care as much about his glasses would damage directly exposed coatings rather quickly, or due to economical reasons as earlier Dienstglas were also externally coated.

dunmunro
Senior Member
Posts: 3061
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: British v German rangefinders

Postby dunmunro » Thu Sep 17, 2015 6:45 pm

Christian VII. wrote:The person on that website is mistaken, he brings no source to the table either :) According to most sources most German optical equipment was coated after 1938 (of which there is plenty of evidence), incl. most army & luftwaffe binocs as well as rifle telescopes - heck even perscription glasses. One way to see this is by looking for the letter T or, since far from all coated equipment bear this marking, simply by visually inspecting the lenses. Most importantly a lot of originally uncoated equipment made before 1936 was re-coated during the war, and the Germans didn't mark their coated rifle scopes at all for example. i.e. a lot of wartime coated optics, if not most, weren't marked at all.

Lots of coated originals for the KM, LW & WM available here: http://www.binoculars-cinecollectors.co ... k_p_4.html

As for the effect of the lens coatings, they really can't be understated (esp. in large complex optical equipment) as with the Zeiss hard coatings the light transmission was improved by over 80% pr. lens, and since most optical equipment used 4 or more lenses (large naval equipment used far more) this added up in the end. This is esp. true with the German use of multicoating, i.e. the coating of all lens surfaces.

Image

But you are right that there are other ways to combat this problem, one is simply to use a lower amount of lenses, but this limits you in other areas, such as magnification & FoV. Another method is by using bigger objective & occular lenses, something the Germans were already doing on top of using coatings, and the Japanese started doing the same in the 1920's.

This is probably also the reason why German & Japanese rangefinders featured so much higher a magnification performance, 50x on the German RF's, and 30x on the Japanese RF's on the Yamato. You needed better glass and/or coatings to achieve this whilst still maintaining an acceptable brightness of image.

Also regarding the Japanese optics, their optics industry was created with help of German advisors and technological support starting in 1917, and many new technologies were traded during WW2, incl. the use of Lanthanum as well as H (Helligkeit) glass. Some more information here:
http://www.referenceforbusiness.com/his ... ATION.html

Thus it is no surprise that Japanese optical equipment impressed the US, they were basically looking at German equipment, albeit uncoated.

PS: I remember reading that prior to the war the British admiralty was very concerned regarding the RN's inferior optical equipment in comparison to regular uncoated Zeiss binoculars. So much so that a competition was arranged with various British optics companies to come up with an equal piece of equipment. IIRC Barr & Stroud came closest, but with a much larger piece of equipment.


Here's the "...The person on that website...":

Dr. Hans T. Seeger, Military Binoculars and Telescopes for Land, Air and Sea Service, 2001, second much expanded edition. The only comprehensive guide to military binoculars currently available. Includes more than 535 pages and many hundreds of illustrations. This is the expanded, 15 year effort by the world's leading binocular historian. A textbook for collectors at any level. Text mostly in German, but with extensive English subtitles and amplifications. This deluxe edition is signed by the author. This IS the definitive text! You gotta have one.
http://deutscheoptik.com/Military-Binoc ... copes.html


Most German and Japanese optics used during WW2 were uncoated. Both the UK and USA had large and very experienced optical industries. The Allies tended towards simple designs in mass produced optics, but in cutting edge applications, such as rangefinders Allied optics were not inferior to Axis optics.

dunmunro
Senior Member
Posts: 3061
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: British v German rangefinders

Postby dunmunro » Thu Sep 17, 2015 6:47 pm

Christian VII. wrote:
dunmunro wrote:
Most German military optics were uncoated, as were most Allied Optics. This information is widely available, and all you have to do is look for it:

"Although some Zeiss Kriegsmarine 6X30’s did have coated optics, the German Army Dienstglas did not."
https://www.flickr.com/photos/binocwpg/7516684888

"1943 10 x 50 Dientsglass...
The BLC dientsglas uncoated model was produced in large quantities."
http://www.binoculars-cinecollectors.co ... 9_10x.html


The first pair is a Swarovski, an Austrian binocular taken into use by the German army. Swarovski didn't use any coatings. The flickr poster is wrong about Germany army Dienstglas not using coatings however, something your 2nd link proves as well.

The 2nd is pair of uncoated Dienstglas, but you only have to scroll down to find that the rest which are presented are mostly coated :)

In addition to that there are a wealth of original coated German army binocs on the same website.

As the website notes however many late war Dienstglas were only internally coated, probably due to knowing that the field conditions of a regular grunt who didn't care as much about his glasses would damage directly exposed coatings rather quickly, or due to economical reasons as earlier Dienstglas were also externally coated.


What I proved was that coated optics were rare in the German Army until very late in the war.

Christian VII.
Member
Posts: 80
Joined: Sat Jan 17, 2015 7:49 am

Re: British v German rangefinders

Postby Christian VII. » Fri Sep 18, 2015 2:16 am

dunmunro wrote:
What I proved was that coated optics were rare in the German Army until very late in the war.


You didn't prove that at all, infact you disproved it with your own link. There are plenty of coated 1940 dated Dienstglass out there, as well as plenty of coated telescopes from the late 30's.

Christian VII.
Member
Posts: 80
Joined: Sat Jan 17, 2015 7:49 am

Re: British v German rangefinders

Postby Christian VII. » Fri Sep 18, 2015 2:47 am

dunmunro wrote:
Here's the "...The person on that website...":

Dr. Hans T. Seeger, Military Binoculars and Telescopes for Land, Air and Sea Service, 2001, second much expanded edition. The only comprehensive guide to military binoculars currently available. Includes more than 535 pages and many hundreds of illustrations. This is the expanded, 15 year effort by the world's leading binocular historian. A textbook for collectors at any level. Text mostly in German, but with extensive English subtitles and amplifications. This deluxe edition is signed by the author. This IS the definitive text! You gotta have one.
http://deutscheoptik.com/Military-Binoc ... copes.html


Well on that point he's wrong, pure and simple. Otherwise there simply wouldn't be so many originally coated Dienstglasses out there, and there are plenty of original field glasses out there to prove it, incl. on the website you linked yourself :) All rnl marked Dienstglasses for example are coated.

Most Dienstglassses were internally coated, so you'll only see this if you take them apart. Furthermore the multicoated dienstglassses are from before 1944, after that they are only internally coated or not coated at all.

But really we're treading water here as Dienstglasses were the cheapest binocs made for the Germany army, and as such it is no surprise that some weren't coated, esp. later in the war.

The main point is that the Germans made far wider use of coatings than did the Allies, mainly because the Germans used Zeiss hard coatings which were more durable and therefore were useful in a wider range of applications. As such all of the German Navy's binoculars, telescopes and RF'ers coated, as were all tank & artillery optics. The same cannot be said of the Allies who used their coatings mostly on large optical instruments, and rarely on smaller equipment, and that because of their softness demanding more careful use.

Most German and Japanese optics used during WW2 were uncoated.


For Japanese optics this is true as they didn't use any coatings at all, but for German optics it is not. Most German optics were infact coated, safe from the cheapest mass produced Dienstglas binocs that didn't really need to be so, esp. as the Lanthanum enriched glass used was already so good that coatings often weren't needed to begin with.

Both the UK and USA had large and very experienced optical industries.


They did, but this is simply an area where the Germans were well ahead of the curve, and had been so since well before WW1. This is something most authors on the subject at least agree upon.

The Allies tended towards simple designs in mass produced optics, but in cutting edge applications, such as rangefinders Allied optics were not inferior to Axis optics.


But they clearly were, as both their coatings and lenses were infact inferior, which also explains why the performance of British & US optics generally was lower, coated or not. Otherwise how would you explain this?

As already noted Allied coatings improved light transmissions by 60% but were very soft, where'as German coatings improved light transmissions by over 80% and were hard/durable. This alone doesn't explain the observed difference in German vs Allied optics, as this was also caused by the superior lanthanum enriched glass used in German equipment, but it explains why the Allies didn't make as widespread a use of coatings as did the Germans - their coatings simply weren't durable enough to be used outside specialist applications.

Paul L
Senior Member
Posts: 290
Joined: Sat Jan 29, 2005 9:04 pm
Location: Vancouver Canada

Re: British v German rangefinders

Postby Paul L » Sun Nov 01, 2015 1:59 am

Christian VII. wrote:


But they clearly were, as both their coatings and lenses were infact inferior, which also explains why the performance of British & US optics generally was lower, coated or not. Otherwise how would you explain this?

As already noted Allied coatings improved light transmissions by 60% but were very soft, where'as German coatings improved light transmissions by over 80% and were hard/durable. This alone doesn't explain the observed difference in German vs Allied optics, as this was also caused by the superior lanthanum enriched glass used in German equipment, but it explains why the Allies didn't make as widespread a use of coatings as did the Germans - their coatings simply weren't durable enough to be used outside specialist applications.
[/quote]

That situation continued well into the 2nd 1/2 of the 20th century. My old man was a scientist and had specialised optical measuring equipment made for his lab. Repeatedly the University demanded he buy Canadian or American products and designs. Every time he had to show them how these were inferior to the Zeiss models that he almost always got in the end.
"Eine mal is kein mal"

dunmunro
Senior Member
Posts: 3061
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: British v German rangefinders

Postby dunmunro » Mon Nov 02, 2015 3:29 am

The UK NPL tested light throughput for WW2 7x50 naval binoculars:

coated Zeiss = 80%
coated B&L = 78%
uncoated B&S = 66% ( all data from Reid)

The operational difference between the Zeiss and B&S would be minimal in actual use.

I've provided abundant data to prove that the vast majority of German binoculars, and other WW2 optics, were uncoated.

Christian VII.
Member
Posts: 80
Joined: Sat Jan 17, 2015 7:49 am

Re: British v German rangefinders

Postby Christian VII. » Wed Nov 11, 2015 3:13 pm

dunmunro wrote:I've provided abundant data to prove that the vast majority of German binoculars, and other WW2 optics, were uncoated.


But you haven't? Even your own sources prove that the most common German optical equipment, the common grunts Dienstglass, were coated in huge numbers.

Also all German tank optics were coated, as were all Hensoldt manufactured rifle scopes after 1939. Heck even the late war ZF4 was coated.

Only really Dienstglasses were sometimes non coated, and then it was mostly the small ones (7x50) and because they didn't need to be.

dunmunro
Senior Member
Posts: 3061
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: British v German rangefinders

Postby dunmunro » Wed Nov 11, 2015 10:10 pm

Christian VII. wrote:
dunmunro wrote:I've provided abundant data to prove that the vast majority of German binoculars, and other WW2 optics, were uncoated.


But you haven't? Even your own sources prove that the most common German optical equipment, the common grunts Dienstglass, were coated in huge numbers.

Also all German tank optics were coated, as were all Hensoldt manufactured rifle scopes after 1939. Heck even the late war ZF4 was coated.

Only really Dienstglasses were sometimes non coated, and then it was mostly the small ones (7x50) and because they didn't need to be.



We've already established that the KM received coated binoculars and many of the models that you linked were naval issue.

These are examples of army binoculars and most were uncoated:

http://www.binoculars-cinecollectors.co ... lnNo100272

http://www.binoculars-cinecollectors.co ... blcNo20938

http://www.binoculars-cinecollectors.co ... xnNo397898

The German army was about 40 times larger than the navy and this is probably the approximate proportion of coated versus uncoated binocular production in Germany from 1939-45: about 1 coated for every 40 uncoated. Coating for army binoculars was introduced, in most cases, late in the war, and many of these binoculars never made it to active service.

Small binoculars were issued in far larger numbers than large binoculars - again it is clear that the vast majority of German binoculars produced during WW2 were uncoated.

I'll repeat an earlier quote:
Seeger, Military Binoculars and Telescopes in Army, Air Force and Marine:
"[page 331] In 1935/36, Alexander Smakula (Zeiss, Jena) developed the
lens coating, a reflection reducing coating for optical elements. For
all optics, especially thoise with numerous surfaces, the coating (also
called 'blue coating') is a valuable means to increase the transparency
and therefore the brightness of the image. In the marine optics, the
coating was especially useful. U-boat periscope optics were the first
to receive this new coating, along with the Navy field glasses. In
Germany, Navy optics and tank aiming field glasses were the only items
manufactured with coated optics; and other German military models
usually didn't have coating (and when it is there, that nearly always
means it was applied later, and the original condition is falsified.)

For military optics from the U.S., Great Britain or Canada, the
sequence is similar to the one in Germany: Marine optics were the first
to receive the blue coat, but only during the course of the war. In
chart 2, we can see that in the U.S. in 1944, coating of military optics
was quite common. At least 5 of the listed models are coated, and since
one model is 'not coated', it is therefore more of an exception than the
rule."

Christian VII.
Member
Posts: 80
Joined: Sat Jan 17, 2015 7:49 am

Re: British v German rangefinders

Postby Christian VII. » Sat Dec 12, 2015 11:35 am

Problem with that claim is that many German rifle scopes were coated during the war (primarily Hensoldt), as were many cameras and army field glasses, of which there is plenty of proof - incl. the links you provided yourself.

To claim that only 1 in 40 were coated is pure conjecture based on nothing really. How many dienstglasses were coated vs how many weren't is impossible to tell, but a very large number clearly were as you've got production codes only featuring coated examples.

The Germans multi coated camera optics, tank sights, rifle scopes, army field glasses & rangefinders with their hard coatings in large scale, something which is easily proven via orginal examples. Infact Leica who had been using soft coatings for a long time started using multi layer hard coatings for their camera lenses in October 1941, and started hard coating all their products along with Leitz in 1942 as all production was diverted to the military and government (Erwin Puts Leica History 1925-1965), hence the many coated Leica cameras out there.

Anyway just based on the number of applications to which the Germans applied their coatings it's safe to say that they made far more use of this than did the Allies, which isn't surprising considering that you need hard coatings in most of these. The German use of multi layer coatings on all surfaces in some of their equipment was also unique.

Paul L
Senior Member
Posts: 290
Joined: Sat Jan 29, 2005 9:04 pm
Location: Vancouver Canada

Re: British v German rangefinders

Postby Paul L » Sun Dec 13, 2015 5:09 am

Not a significant point but the KM was 1/2 to 3/4 million through the mid to late war while the Heer was 2.5-> 7 million so the German army was hardly ' 40 times' the size of the navy.
"Eine mal is kein mal"

dunmunro
Senior Member
Posts: 3061
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: British v German rangefinders

Postby dunmunro » Mon Dec 14, 2015 7:46 am

Paul L wrote:Not a significant point but the KM was 1/2 to 3/4 million through the mid to late war while the Heer was 2.5-> 7 million so the German army was hardly ' 40 times' the size of the navy.


KM strength was about 50k in 1940 versus 4.5 million in the Army (Heer)

http://www.feldgrau.com/stats.html

KM peak strength was about 800k versus 7.3 million for the Army/SS however KM numbers are quite misleading, since for example, the peak strength of the all the Commonwealth Navies was barely greater than 1 million:

http://www.naval-history.net/WW2CampaignRoyalNavy.htm

The vast majority of KM personnel were not in combat units and their demand for coated naval binoculars would have been quite limited in comparison to the Heer.

Paul L
Senior Member
Posts: 290
Joined: Sat Jan 29, 2005 9:04 pm
Location: Vancouver Canada

Re: British v German rangefinders

Postby Paul L » Wed Dec 16, 2015 7:22 am

I will go with the "Oxford companion to World War two" , which reports the KM numbers as 190,000 in 1940 -while the Heer/SS was 4.5 million, which is about 23:1.

In 1944v the KM figures are reported at 810,000 while the HEER/SS are reported at 7.1 million ; which is about 9:1...again hardly 40:1. The vast majority of the KM personnel by 1944 were manning the ATLANTIC WALL and indeed did require binoculars.
"Eine mal is kein mal"

dunmunro
Senior Member
Posts: 3061
Joined: Sat Oct 22, 2005 1:25 am
Location: Langley BC Canada

Re: British v German rangefinders

Postby dunmunro » Thu Dec 17, 2015 4:21 pm

Heer divisional scales of equipment call for several pairs of binoculars, even at the platoon level. Scaling that up you can see that the Heer's use of binoculars far exceeded the KM's on a per capita basis.


Return to “Naval Technology”

Who is online

Users browsing this forum: No registered users and 1 guest