pablo18
Member
1) INTRODUCTION
First of all, I would like to clarify that I am not an expert on German lenses. I am simply an amateur who finds it interesting to study historical aspects associated with early photographic optics. I therefore apologize in advance for any errors or omissions. Any corrections or additional information will be most welcome.
A particularly interesting historical moment for lenses produced by Carl Zeiss Jena is the period corresponding to the first months and years after the war. When referring to this stage, however, it is important to distinguish between the years 1945–1946 and the period that formally begins in March 1947 with serial number 3000001, when production resumed after the factory had been almost completely dismantled by the Soviet authorities.
My purpose here is to conduct a small exercise in industrial archaeology by visually comparing and analyzing the changes observed in some of the very earliest Carl Zeiss Jena lenses produced in the series beginning with serial number 3000001, at a time when the factory was restarting operations under particularly difficult conditions.
More specifically, I will present images of several examples of the Carl Zeiss Jena Tessar 5 cm f/3.5 in Exakta mount within a very early serial range, spanning from 3000025 to 3045958, the latter corresponding to the appearance (or reappearance) of the red “T” coating mark. It should be noted that the reason for focusing on a single lens model is that different optical designs evolved in different ways during this period. Therefore, the observations presented here for the Tessar 5 cm f/3.5 in Exakta mount cannot necessarily be extrapolated to other lenses such as the Sonnar or the Biotar.
My interest here is to concentrate on the changes occurring within a very short time span beginning with serial number 3000001, in order to observe how the peculiarities of a very specific historical moment are reflected in a particular industrial product.
All production dates and batch references cited here are taken from the reference work by Hartmut Thiele, Fabrikationsbuch Photooptik II – Carl Zeiss Jena (10th edition, 2023).
The aspects examined include variations in the size of characters used in the distance scale and serial engravings, the appearance of additional, white-painted or inverted serial numbers, differences in character spacing, and markings related to the introduction of lens coating (including a Red Dot of apparently experimental character and the later standardized red “T” marking).
The eight lenses considered in this comparison are the following:
- 3000025 (uncoated, batch of 1000, production date listed as 24 March 1947)
- 3000091 (uncoated, same batch as the previous lens)
- 3000307 (uncoated, same batch as the previous lenses, assembled with a component from 3002358)
- 3005392 (uncoated, batch of 1000, production date listed as 24 March 1947)
- 3019163 (uncoated, batch of 1500, production date listed as 1 April 1947)
- 3021847 (Red Dot, coated, batch of 500, production date listed as 24 March 1947)
- 3023125 (uncoated, batch of 500, production date listed as 24 March 1947)
- 3045958 (red “T”, coated, batch of 1500, production date listed as 16 July 1947)
Although several of the production dates listed in the tables are identical or very close to one another, the images presented below show that a clear evolution nevertheless took place.
For simplicity, from this point onward I will refer to the lenses using only the sequence number derived from serial 3000001. Thus, lens 3000025 will be referred to as lens 25, 3021847 as lens 21847, and so on. The lenses discussed in the images are therefore numbers 25, 91, 307 (assembled with 2358), 5392, 19163, 21847, 23125 and 45958.
An important note regarding previous documentation: additional examples of early post-war Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount can be found on the website photobutmore.de, which documents and discusses several specimens including early serial numbers such as 192 and 1722. The present comparison complements those examples by examining a continuous sequence of lenses between 25 and 45958, with a particular focus on very early variations.
The choice of lens 45958 is not arbitrary. Based on the batches examined so far, it appears to belong to the first post-war batch—ranging from serial numbers 45101 to 46600—in which Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount appear marked with the Red T coating symbol. This observation is also consistent with information presented on the website photobutmore.de, where it is stated that coated lenses from approximately the 45xxx range received a red “T” marking. While further examples may refine this observation, the available evidence suggests that this batch represents the earliest regular appearance of the Red T marking for this model. For this reason, the working criterion adopted here is to consider the range from serial 1 to 46600 as representing a very early stage in the post-war production of this lens by Carl Zeiss Jena.
The structure of this thread is as follows:
1) INTRODUCTION
2) COMPARISON OF LENSES 25 AND 91
3) LENS 307 (ASSEMBLED WITH 2358)
4) LENS 5392
5) LENS 21847 (RED DOT) AND COMPARISON WITH LENSES 19163 AND 23125
6) RED DOT VS. RED “T”: COMPARISON OF LENSES 21847, 45958 AND 23125
7) FINAL COMMENTS
2) COMPARISON OF LENSES 25 AND 91
We have here two very early examples of post-war production: lenses 25 and 91. As can be seen in the photographs below, both are uncoated and both display the serial number twice: once on the front ring, and again on the inner bayonet mount. This is consistent with the observations reported on the website photobutmore.de regarding lens 192, which belongs to the same production batch as lenses 25 and 91.
Now, if we look closely at the third and fourth photographs, we can observe an appreciable difference in the size of the numerals appearing on the distance scales of lenses 25 (left) and 91 (right). This occurs despite the fact that both lenses belong to the same batch, and moreover that they are separated by only 66 units. It is unclear whether this reflects the use of different engraving templates, different engraving machines, or a lack of full standardization during this very early stage of post-war production.
In the following sections we will see how some of these characteristics were modified as production gradually stabilized.
3) LENS 307 (ASSEMBLED WITH 2358)
We now present images of lens 307, which belongs to the same batch as lenses 25 and 91 and therefore naturally shares their general characteristics.
However, if we examine the second photograph, we observe a noteworthy detail. While the serial number visible on the inner mount is again 307, an additional serial number is also visible on the outer mount, belonging to another lens: 2358.
On the one hand, this indicates that the present lens was assembled using components from two different lenses. On the other hand, it also suggests that starting with the batch to which lens 2358 belongs, the lenses began to display the serial number three times: once on the front ring and twice on the mount.
This is consistent with the observation reported on the website photobutmore.de regarding lens 1722, which belongs precisely to the same batch as lens 2358. That batch consists of 900 pieces and is listed with a production date of 24 March 1947.
But why were components from two different batches used to assemble this lens? In this case, the explanation that this is a later, non-factory assembly appears unlikely. The reason is the following: the batches to which lenses 307 and 2358 belong are adjacent Tessar batches, separated only by a batch of 600 Sonnar lenses. It is therefore quite possible that lenses from both batches were being assembled at roughly the same time.
In this context — a gradual return to production in a factory operating with severely reduced capacity — the simplest and most coherent explanation is that a worker assembled the lens using parts from these two different batches, and that the lens already left the factory in this configuration.
4) LENS 5392
We now turn to lens 5392, whose images are shown below. This lens is also uncoated, but it already displays several characteristics that will remain present in production over the following batches. For example, in the second photograph we can confirm what was anticipated in the previous section: on the mount, the serial number now appears twice.
The third photograph compares lens 5392 with the very early lens 25. Examining the serial number on the inner mount, we can see that, unlike lens 25, in lens 5392 the digits are smaller, more widely spaced, and filled with white pigment. In addition, they are inverted.
At this point it might appear that the typology has begun to stabilize. However, in the next section we will witness the appearance of a curious mutant — a disruptive element.
5) LENS 21847 (RED DOT) AND COMPARISON WITH LENSES 19163 AND 23125
At this point a specimen appears that stands out clearly from the previously described pattern: lens 21847, the so-called Red Dot lens, which presents three notable differences compared with its neighboring Tessar lenses.
First of all, one immediately notices the presence of a large red dot on the front ring, positioned between the focal length marking and the manufacturer’s name. This red dot can be seen in the first photograph.
Secondly, unlike other Tessar lenses in similar serial number ranges—which are all uncoated—this lens shows a coating with lilac or violet reflections on both the front and rear elements, as can be seen in the first two photographs.
Thirdly, the serial number engraved on the inner mount differs typographically from those found on neighboring lenses. The digits are not filled with the white pigment seen on those lenses, and they are also noticeably more widely spaced. This can be clearly observed in the third photograph, where the rear mounts of lenses 21847 and 23125 are compared. The comparison also highlights the strong contrast between the presence of coating on the former and its absence on the latter.
The remaining photographs present additional comparisons between lens 21847 and lenses 19163 and 23125, which have similar serial numbers but are nevertheless uncoated and lack the other distinctive features observed on 21847.
The Red Dot therefore appears not merely as an isolated marking, but as part of a broader set of distinctive features associated with this specimen.
As for the purpose of this lens, one may speculate that it represents a test related to coating techniques, possibly intended to establish the regular use of coated optics in post-war production. This would later occur with the appearance of the Red T mark on Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount, presumably beginning with the batch starting at lens 45101. (Other optical designs received the Red T mark at lower post-war serial numbers, but that subject will not be addressed here.)
In this context, both the large red dot and the unusual typology of the serial digits on the inner mount may have served a practical function—allowing the lens to be quickly identified, for example on a workbench containing many similar Tessars.
At this point one may ask whether this lens represents a unique specimen or whether other lenses from the same batch received similar treatment. The batch consisted of 500 units, and since I have not yet been able to locate any other surviving examples from it, this question remains open for the time being.
6) RED DOT VS. RED “T”: COMPARISON OF LENSES 21847, 45958 AND 23125
As discussed in the Introduction, in order to close the present analysis of the earliest stage of post-war production of the Carl Zeiss Tessar 5 cm f/3.5 in Exakta mount, we now turn our attention to lens 45958. This specimen belongs to what appears to be the first batch (45101–46600) in which the Red T marking, indicating the presence of coating, appears on this optical design. As noted earlier, other optical designs received the Red T marking at lower post-war serial numbers, a subject that could merit further investigation.
The first two photographs show the front and rear elements of the lens, revealing the presence of coating in light lilac or pale violet tones. At this point a brief note is necessary. As can be seen in the first photograph, and even more clearly in the second and in some of the images that follow, both elements of this specimen—particularly the rear one—show coating deterioration near the edge, likely due to past fungal activity. This condition should therefore be taken into account when considering the exact hue of the reflections observed. Fortunately, the central area of the element remains largely unaffected, and the presence of coating can still be clearly observed. As the present study focuses on external construction features rather than optical performance, this condition does not significantly affect the analysis presented here. In the future I will probably have some of these lenses professionally cleaned, but for the purposes of this thread I have preferred to photograph them in the same condition in which they arrived in my hands.
In the third and fourth photographs we present the inevitable comparison with the Red Dot lens (21847). The coating tones appear broadly similar, although those of lens 45958 are lighter and more lilac in color. At first glance this difference might reflect the experimental nature of coating processes during the earliest post-war production phase at Carl Zeiss Jena, before the process became fully standardized. However, an important qualification must be made. While lens 21847 is in close-to-mint condition, and the coating tones it displays are likely very close to those it had when leaving the factory, lens 45958 shows signs of use and wear, so that it is possible that its coating tones may have been attenuated over time by various environmental factors.
As a future line of investigation, it would be interesting to examine additional specimens from this same batch (45101–46600) in order to perform further comparisons.
The remaining photographs present additional comparisons that include lens 23125, which is uncoated. In particular, note in the last photograph the difference in size and spacing between the digits of the serial numbers engraved on the inner mounts of lenses 23125 and 45958.
7) FINAL COMMENTS
It is interesting to observe that, while the production dates listed for the lenses considered here are generally identical—or at least very close to one another—the direct examination of the physical specimens reveals clear differences that indicate an evident evolution.
It is also noteworthy that milestones such as the appearance of a second serial number on the mount, the presence of a coated lens marked with a red dot, or the later introduction of lenses marked with the Red T, do not appear to be explicitly recorded in the available production registers.
In my opinion, this highlights the importance of the physical examination of surviving specimens as a complement to documentary research.
Naturally, I have not been able to examine examples from every existing batch of Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount within the serial number range from 1 to 46600. If anyone can provide additional information or corrections regarding the observations presented here, I would be most grateful.
The photograph below shows the lenses discussed in this thread together with the reference work by Hartmut Thiele (Fabrikationsbuch Photooptik II – Carl Zeiss Jena, tenth edition, 2023), from which all production dates and batch information cited above were obtained.
First of all, I would like to clarify that I am not an expert on German lenses. I am simply an amateur who finds it interesting to study historical aspects associated with early photographic optics. I therefore apologize in advance for any errors or omissions. Any corrections or additional information will be most welcome.
A particularly interesting historical moment for lenses produced by Carl Zeiss Jena is the period corresponding to the first months and years after the war. When referring to this stage, however, it is important to distinguish between the years 1945–1946 and the period that formally begins in March 1947 with serial number 3000001, when production resumed after the factory had been almost completely dismantled by the Soviet authorities.
My purpose here is to conduct a small exercise in industrial archaeology by visually comparing and analyzing the changes observed in some of the very earliest Carl Zeiss Jena lenses produced in the series beginning with serial number 3000001, at a time when the factory was restarting operations under particularly difficult conditions.
More specifically, I will present images of several examples of the Carl Zeiss Jena Tessar 5 cm f/3.5 in Exakta mount within a very early serial range, spanning from 3000025 to 3045958, the latter corresponding to the appearance (or reappearance) of the red “T” coating mark. It should be noted that the reason for focusing on a single lens model is that different optical designs evolved in different ways during this period. Therefore, the observations presented here for the Tessar 5 cm f/3.5 in Exakta mount cannot necessarily be extrapolated to other lenses such as the Sonnar or the Biotar.
My interest here is to concentrate on the changes occurring within a very short time span beginning with serial number 3000001, in order to observe how the peculiarities of a very specific historical moment are reflected in a particular industrial product.
All production dates and batch references cited here are taken from the reference work by Hartmut Thiele, Fabrikationsbuch Photooptik II – Carl Zeiss Jena (10th edition, 2023).
The aspects examined include variations in the size of characters used in the distance scale and serial engravings, the appearance of additional, white-painted or inverted serial numbers, differences in character spacing, and markings related to the introduction of lens coating (including a Red Dot of apparently experimental character and the later standardized red “T” marking).
The eight lenses considered in this comparison are the following:
- 3000025 (uncoated, batch of 1000, production date listed as 24 March 1947)
- 3000091 (uncoated, same batch as the previous lens)
- 3000307 (uncoated, same batch as the previous lenses, assembled with a component from 3002358)
- 3005392 (uncoated, batch of 1000, production date listed as 24 March 1947)
- 3019163 (uncoated, batch of 1500, production date listed as 1 April 1947)
- 3021847 (Red Dot, coated, batch of 500, production date listed as 24 March 1947)
- 3023125 (uncoated, batch of 500, production date listed as 24 March 1947)
- 3045958 (red “T”, coated, batch of 1500, production date listed as 16 July 1947)
Although several of the production dates listed in the tables are identical or very close to one another, the images presented below show that a clear evolution nevertheless took place.
For simplicity, from this point onward I will refer to the lenses using only the sequence number derived from serial 3000001. Thus, lens 3000025 will be referred to as lens 25, 3021847 as lens 21847, and so on. The lenses discussed in the images are therefore numbers 25, 91, 307 (assembled with 2358), 5392, 19163, 21847, 23125 and 45958.
An important note regarding previous documentation: additional examples of early post-war Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount can be found on the website photobutmore.de, which documents and discusses several specimens including early serial numbers such as 192 and 1722. The present comparison complements those examples by examining a continuous sequence of lenses between 25 and 45958, with a particular focus on very early variations.
The choice of lens 45958 is not arbitrary. Based on the batches examined so far, it appears to belong to the first post-war batch—ranging from serial numbers 45101 to 46600—in which Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount appear marked with the Red T coating symbol. This observation is also consistent with information presented on the website photobutmore.de, where it is stated that coated lenses from approximately the 45xxx range received a red “T” marking. While further examples may refine this observation, the available evidence suggests that this batch represents the earliest regular appearance of the Red T marking for this model. For this reason, the working criterion adopted here is to consider the range from serial 1 to 46600 as representing a very early stage in the post-war production of this lens by Carl Zeiss Jena.
The structure of this thread is as follows:
1) INTRODUCTION
2) COMPARISON OF LENSES 25 AND 91
3) LENS 307 (ASSEMBLED WITH 2358)
4) LENS 5392
5) LENS 21847 (RED DOT) AND COMPARISON WITH LENSES 19163 AND 23125
6) RED DOT VS. RED “T”: COMPARISON OF LENSES 21847, 45958 AND 23125
7) FINAL COMMENTS
2) COMPARISON OF LENSES 25 AND 91
We have here two very early examples of post-war production: lenses 25 and 91. As can be seen in the photographs below, both are uncoated and both display the serial number twice: once on the front ring, and again on the inner bayonet mount. This is consistent with the observations reported on the website photobutmore.de regarding lens 192, which belongs to the same production batch as lenses 25 and 91.
Now, if we look closely at the third and fourth photographs, we can observe an appreciable difference in the size of the numerals appearing on the distance scales of lenses 25 (left) and 91 (right). This occurs despite the fact that both lenses belong to the same batch, and moreover that they are separated by only 66 units. It is unclear whether this reflects the use of different engraving templates, different engraving machines, or a lack of full standardization during this very early stage of post-war production.
In the following sections we will see how some of these characteristics were modified as production gradually stabilized.
3) LENS 307 (ASSEMBLED WITH 2358)
We now present images of lens 307, which belongs to the same batch as lenses 25 and 91 and therefore naturally shares their general characteristics.
However, if we examine the second photograph, we observe a noteworthy detail. While the serial number visible on the inner mount is again 307, an additional serial number is also visible on the outer mount, belonging to another lens: 2358.
On the one hand, this indicates that the present lens was assembled using components from two different lenses. On the other hand, it also suggests that starting with the batch to which lens 2358 belongs, the lenses began to display the serial number three times: once on the front ring and twice on the mount.
This is consistent with the observation reported on the website photobutmore.de regarding lens 1722, which belongs precisely to the same batch as lens 2358. That batch consists of 900 pieces and is listed with a production date of 24 March 1947.
But why were components from two different batches used to assemble this lens? In this case, the explanation that this is a later, non-factory assembly appears unlikely. The reason is the following: the batches to which lenses 307 and 2358 belong are adjacent Tessar batches, separated only by a batch of 600 Sonnar lenses. It is therefore quite possible that lenses from both batches were being assembled at roughly the same time.
In this context — a gradual return to production in a factory operating with severely reduced capacity — the simplest and most coherent explanation is that a worker assembled the lens using parts from these two different batches, and that the lens already left the factory in this configuration.
4) LENS 5392
We now turn to lens 5392, whose images are shown below. This lens is also uncoated, but it already displays several characteristics that will remain present in production over the following batches. For example, in the second photograph we can confirm what was anticipated in the previous section: on the mount, the serial number now appears twice.
The third photograph compares lens 5392 with the very early lens 25. Examining the serial number on the inner mount, we can see that, unlike lens 25, in lens 5392 the digits are smaller, more widely spaced, and filled with white pigment. In addition, they are inverted.
At this point it might appear that the typology has begun to stabilize. However, in the next section we will witness the appearance of a curious mutant — a disruptive element.
5) LENS 21847 (RED DOT) AND COMPARISON WITH LENSES 19163 AND 23125
At this point a specimen appears that stands out clearly from the previously described pattern: lens 21847, the so-called Red Dot lens, which presents three notable differences compared with its neighboring Tessar lenses.
First of all, one immediately notices the presence of a large red dot on the front ring, positioned between the focal length marking and the manufacturer’s name. This red dot can be seen in the first photograph.
Secondly, unlike other Tessar lenses in similar serial number ranges—which are all uncoated—this lens shows a coating with lilac or violet reflections on both the front and rear elements, as can be seen in the first two photographs.
Thirdly, the serial number engraved on the inner mount differs typographically from those found on neighboring lenses. The digits are not filled with the white pigment seen on those lenses, and they are also noticeably more widely spaced. This can be clearly observed in the third photograph, where the rear mounts of lenses 21847 and 23125 are compared. The comparison also highlights the strong contrast between the presence of coating on the former and its absence on the latter.
The remaining photographs present additional comparisons between lens 21847 and lenses 19163 and 23125, which have similar serial numbers but are nevertheless uncoated and lack the other distinctive features observed on 21847.
The Red Dot therefore appears not merely as an isolated marking, but as part of a broader set of distinctive features associated with this specimen.
As for the purpose of this lens, one may speculate that it represents a test related to coating techniques, possibly intended to establish the regular use of coated optics in post-war production. This would later occur with the appearance of the Red T mark on Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount, presumably beginning with the batch starting at lens 45101. (Other optical designs received the Red T mark at lower post-war serial numbers, but that subject will not be addressed here.)
In this context, both the large red dot and the unusual typology of the serial digits on the inner mount may have served a practical function—allowing the lens to be quickly identified, for example on a workbench containing many similar Tessars.
At this point one may ask whether this lens represents a unique specimen or whether other lenses from the same batch received similar treatment. The batch consisted of 500 units, and since I have not yet been able to locate any other surviving examples from it, this question remains open for the time being.
6) RED DOT VS. RED “T”: COMPARISON OF LENSES 21847, 45958 AND 23125
As discussed in the Introduction, in order to close the present analysis of the earliest stage of post-war production of the Carl Zeiss Tessar 5 cm f/3.5 in Exakta mount, we now turn our attention to lens 45958. This specimen belongs to what appears to be the first batch (45101–46600) in which the Red T marking, indicating the presence of coating, appears on this optical design. As noted earlier, other optical designs received the Red T marking at lower post-war serial numbers, a subject that could merit further investigation.
The first two photographs show the front and rear elements of the lens, revealing the presence of coating in light lilac or pale violet tones. At this point a brief note is necessary. As can be seen in the first photograph, and even more clearly in the second and in some of the images that follow, both elements of this specimen—particularly the rear one—show coating deterioration near the edge, likely due to past fungal activity. This condition should therefore be taken into account when considering the exact hue of the reflections observed. Fortunately, the central area of the element remains largely unaffected, and the presence of coating can still be clearly observed. As the present study focuses on external construction features rather than optical performance, this condition does not significantly affect the analysis presented here. In the future I will probably have some of these lenses professionally cleaned, but for the purposes of this thread I have preferred to photograph them in the same condition in which they arrived in my hands.
In the third and fourth photographs we present the inevitable comparison with the Red Dot lens (21847). The coating tones appear broadly similar, although those of lens 45958 are lighter and more lilac in color. At first glance this difference might reflect the experimental nature of coating processes during the earliest post-war production phase at Carl Zeiss Jena, before the process became fully standardized. However, an important qualification must be made. While lens 21847 is in close-to-mint condition, and the coating tones it displays are likely very close to those it had when leaving the factory, lens 45958 shows signs of use and wear, so that it is possible that its coating tones may have been attenuated over time by various environmental factors.
As a future line of investigation, it would be interesting to examine additional specimens from this same batch (45101–46600) in order to perform further comparisons.
The remaining photographs present additional comparisons that include lens 23125, which is uncoated. In particular, note in the last photograph the difference in size and spacing between the digits of the serial numbers engraved on the inner mounts of lenses 23125 and 45958.
7) FINAL COMMENTS
It is interesting to observe that, while the production dates listed for the lenses considered here are generally identical—or at least very close to one another—the direct examination of the physical specimens reveals clear differences that indicate an evident evolution.
It is also noteworthy that milestones such as the appearance of a second serial number on the mount, the presence of a coated lens marked with a red dot, or the later introduction of lenses marked with the Red T, do not appear to be explicitly recorded in the available production registers.
In my opinion, this highlights the importance of the physical examination of surviving specimens as a complement to documentary research.
Naturally, I have not been able to examine examples from every existing batch of Carl Zeiss Jena Tessar 5 cm f/3.5 lenses in Exakta mount within the serial number range from 1 to 46600. If anyone can provide additional information or corrections regarding the observations presented here, I would be most grateful.
The photograph below shows the lenses discussed in this thread together with the reference work by Hartmut Thiele (Fabrikationsbuch Photooptik II – Carl Zeiss Jena, tenth edition, 2023), from which all production dates and batch information cited above were obtained.
