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Michael Graves
19-Aug-2011, 09:59
Just for Schlitz and Gins a couple of weekends ago I shot two negatives of the same image. One was with a Fujinon 150mm and the other with a 150 Zeiss Tessar. On the ground glass, they didn't look much different. It looked like the Fuji might be ever so slightly wider than the Tessar. But that didn't surprise or bother me. Few lenses are precisely what their advertised focal length state.

It was the printing of the negatives that surprised me. The negatives were developed in the same run in a Jobo 310, using Rodinal 1:50. While I expected a bit of contrast difference, I didn't expect it to require a full grade. The Fuji generated that much more contrast. No matter how hard, tried, using different papers and everything, I could not get a print from the Fuji negative that had as wide of a tonal range as the Tessar. I determined contrast by making test strips for the highlights and dialing in/out filtration on a variable contrast cold light head until the shadow matched. The mid tones were where the prints differed. The Fuji certainly looked nice, for certain types of images would be my preference. But the Tessar had creamier middle values. What aspect of a lens causes that. It was a low-flare situation--a weathered barn under an overcast sky with a compendium lens shade for both lenses--so I don't think it was that.

I tried scanning both prints to post the comparisons, but you really can't see the difference in the digital scans, so I won't waste server bandwith. (The images were just test images of a barn anyway. And who wants to look at another barn?)

E. von Hoegh
19-Aug-2011, 12:59
Is the Tessar coated?

Adamphotoman
19-Aug-2011, 13:15
German lenses have historically had less contrast and perhaps more mid tones/ and maybe more detail and sharpness; where Japanese optics have had more contrast and perhaps less mid tones.

I would expect one paper grade.

Under expose the German glass by 1/3 stop and process 10% longer. The opposite can be done for the Japanese glass.

Copy work would always boost contrast so overexposing and under developing helped a lot.

jp
19-Aug-2011, 13:57
If the Zeiss were less clean (fingerprints, atmospheric crud deposits like on a car window, st. bernard slobber) it would have noticeably less contrast as well.

While Zeiss was a innovator in coating, if it predated their coating (WWII ish), that would naturally reduce contrast as well. Lens coating reduces natural reflections between pieces of glass in the lens. Thats much of why lenses with larger numbers of elements weren't common before coating; too much glass surfaces == too many reflections, making them less practical. Triplets and tessars reduced reflections by their simplicity.

jp
19-Aug-2011, 14:00
If you used different lensboards, you might make sure the lensboards are equally blackened on the back too. (to prevent internal camera reflection.)

GPS
19-Aug-2011, 14:07
You don't say the film format, you don't say the coverage of the lenses... Light inside bellows is not the same with lenses of different coverage etc.

Ken Lee
19-Aug-2011, 14:08
"...the Tessar had creamier middle values."

This has been my experience too. I use a variety of Tessars for portraits and flower images, for that very reason. See this short piece (http://www.kenleegallery.com/html/tech/index.php#Vintage) for sample photos such as this one (http://www.kenleegallery.com/html/tech/chey2011.html), made with a double-coated 250mm Tessar on 4x5 film.

While some of my Tessars are fairly modern, and multi-coated, they are always smoother, with creamier mid-tones - just as you have observed. The effects are seen even when using a compendium lens shade.

I prefer Fujinon lenses for landscape and still-life images suited for a razor-sharp look.

Another advantage of Tessars is that many come in older shutters with near-circular apertures: nicer blur rendering

It's subjective, but I find Sironars somewhere in-between the two extremes. I wouldn't want to be stuck with only Tessars or Fujinons, but could survive quite nicely with a full range of Sironars :)

Robert A. Zeichner
19-Aug-2011, 14:17
I've written an article about the importance of using a proper lens shade to reduce the amount of non-image forming light from getting inside the lens and the camera. In situations where you are using uncoated or single coated lenses, this can make a world of difference in the contrast of the resulting negative. It would also make a difference if you were using a lens with far greater coverage than the size of film in use would require. Point is, it's not just the optic itself, but what the non-image forming light might be doing to increase flare both in the lens and in the camera (in the case of bellows flare). Read this http://web.mac.com/razeichner/RAZP_large_pix/Shade_pg_1.html and take a look at the examples made with a single coated Angulon.

IanG
19-Aug-2011, 14:20
That sounds about right.

I use uncoated CZJ Tessar's and older lenses alongside a coated Tessar (50's), Xenar (very early 2000's) an then my MC lenses.

Yes uncoatyed lenses have a very different tonality but much of that is from internal flare and that's there regardless of the lighting conditions.

There's a different tonality with uncoated lenses, you have to see and learnm it for yourself.

Ian

Dan Fromm
19-Aug-2011, 15:22
Are you sure your Tessar's shutter is not running slow?

Mark Sawyer
19-Aug-2011, 17:23
I'm with Dan on this one... are the densities similar? Were the processed identically/together?

And I assume the Tessar was uncoated? Unlike Ken, I've found my modern coated Tessars (Nikkor 450-M, Fujinon-L) are as "harsh" as other modern lenses.

Ken Lee
19-Aug-2011, 17:45
I should qualify: all mine are named Carl Zeiss Jena Tessar.

Michael Graves
19-Aug-2011, 19:05
Is the Tessar coated?

I don't think so. But wouldn't that be a flare issue?

Michael Graves
19-Aug-2011, 19:12
I should qualify: all mine are named Carl Zeiss Jena Tessar.

As is mine. It is circa 1950 if my serial nuimber research is accurate. I can see the internal flare being an issue. I hadn't thought of that. I think that with the compendium in place (and I do have a lot of experience using them, so I'm confident I maximized its effectiveness), that external flare was not a factor. As I stated, the development was done at the same time in the same Jobo tank. The lensboards are both nearly new Shen Hao brand, so the blacking is close enough to identical that you would need a spectrometer to see the results. Negative density is much closer that I would have expected. So the 1/25 of the old shutter is very close to the 1/30 of the Copal. Just looking at the negatives is is very difficult to tell them apart. Had I not included a dog in the Tessar shot, I would not be able to.

Okay, I'll admit. I didn't plan the dog. I just got lucky.

Mark Sawyer
19-Aug-2011, 19:44
I should qualify: all mine are named Carl Zeiss Jena Tessar.

I would love to pull apart and analyze the glass of the different elements of Zeiss, Wollensak, and Nikkor Tessars, especially for the refractive indexes, and see what the differences are...

IanG
20-Aug-2011, 02:45
I should qualify: all mine are named Carl Zeiss Jena Tessar.

Ken, I'm quite surprised that you're getting a creamy effect with a coated Tessar.

My experience with an earl5 1950's T coated CZJ 150mm f4.5 Tessar is that it behaves just like my late production 150mm 5.6 Xenar for B&W work, it does have a distinct blue cast if uised for colour. Tonally there's no noticeable difference compared to my MC Symmar's and Sironar's.

The few uncoated Tessar's I use do exhibit that creamy effect which is normal for uncoated lenses and also results in a diminishing of fine details..

Perhaps the differences between your Tessar's and Fujinon's is more to do with the Japanese approach to lens design which is most noticeable with smaller format lenses. The usual comparison is Leica versus Nikon lenses, the Leitz glass gives better tonality, higher definition, but the Nikkor lens have better contrast which gives the apperance of greater sharpness and a slightly harsher images.

Ian

genotypewriter
21-Aug-2011, 22:41
I would love to pull apart and analyze the glass of the different elements of Zeiss, Wollensak, and Nikkor Tessars, especially for the refractive indexes, and see what the differences are...Comparing refractive indices of elements of a given design/formula means very little. First, because the lenses are simple I doubt you'll see many differences. Secondly, differences in refractive indices don't mean one lens is better than the other, which is what I assume you want to know.

So, what would be more interesting is measuring the dispersion of the elements. You can get elements with the same refractive index but different levels of dispersion. Lower dispersion glass is better and more expensive. This is where manufacturers have a choice when the design/formula is given (i.e. Tessar in this case). So you can find out whether more expensive Tessars are actually made with better glass or not, etc.

GTW

IanG
21-Aug-2011, 23:56
Just an observation but looking at the photo on Ken's site of his DDR CZJ Tessar the aperture blades seem to show the lens may have a trace of internal haze. It's a coated lens so there should be almost no internal reflections.

The photo reminds me of my 1931 135mm CZJ Tessar which has a slight hazy look despite the glass being in excellent condition.

Ian

Mark Sawyer
22-Aug-2011, 09:20
Comparing refractive indices of elements of a given design/formula means very little. First, because the lenses are simple I doubt you'll see many differences. Secondly, differences in refractive indices don't mean one lens is better than the other, which is what I assume you want to know.

So, what would be more interesting is measuring the dispersion of the elements. You can get elements with the same refractive index but different levels of dispersion. Lower dispersion glass is better and more expensive. This is where manufacturers have a choice when the design/formula is given (i.e. Tessar in this case). So you can find out whether more expensive Tessars are actually made with better glass or not, etc.

GTW

My understanding is that lower-dispersion is not always the best in multi-element design, as elements sometimes recombine rays spread by chromatic aberration. But I'm hardly an expert, so you may know better!

My (admittedly idle) curiousity about the refractive index of glass by different manufacturers in the same lens isn't so much about image quality as it is whether designers were closely copying each other or re-interpreting the design. I tend to think there was a lot of re-interpretation with the Tessars, because I notice Tessars of the same focal length and maximum aperture with noticeably different element thicknesses.

Ken Lee
22-Aug-2011, 09:32
Just an observation but looking at the photo on Ken's site of his DDR CZJ Tessar the aperture blades seem to show the lens may have a trace of internal haze. It's a coated lens so there should be almost no internal reflections.

The photo reminds me of my 1931 135mm CZJ Tessar which has a slight hazy look despite the glass being in excellent condition.

Ian

I'll try to get a better photo of the lens. The photo on my site (shown below) is rather small, and if it looks hazy, it's probably just a coincidence.

http://www.kenleegallery.com/images/forum/tessarX.jpg

Lynn Jones
22-Aug-2011, 16:44
You didn't say what kind of Fujinon lens you were comparing, they came in tessar type, two different kinds of plamat type, significantly different. The Fujinon T (as in most tessars covered 56), covered 59 deg, the conventionally coated plasmats covered in some cases up to 80 deg, while the multicoated covered several degrees less and were lower in contrast (all air spaced contruction).

Lynn

IanG
23-Aug-2011, 15:21
I'll try to get a better photo of the lens. The photo on my site (shown below) is rather small, and if it looks hazy, it's probably just a coincidence.

http://www.kenleegallery.com/images/forum/tessarX.jpg

I had a good look at my 1950's LF 150mm Tessar last night and yes it's hard to tell from a photo whether it's haze, but I have a niggle, (a gut feeling).

Many of my LF lenses are Multi coated Rodenstok's and Schneider's and the coatings are so good I turned my back on non MC lenses 30+ years ago. I have to admit my experience of coated & MC lenses was jauniced by some poor quality lenses in tererms of flare in the 70's while maionly shooting 35mm. Sigma & Hoya lenses called MC that flared so badly they were almost useless, in fact the Hoya range was.

So in recent years I was anti coated lenses, I won't say single coated as many non MC lenses hade more than one coating. I've posted here on APUG in the past saying only use MC lenses.

Then I realised I was using a coated 65mm f8 Angulon, and had also been using a coated 90mm f6.8 Angulon, later a pre-MC 90mm f5.6mm SA a and seeing no difference between them and my MC LF lenses which I was using alongside. Later I added a Crown Graphic with a 1931 135mm f4.5 Tessar - that was a retrograde sep, a flat lens in terms of micro contrasts, OK stopped down but not comparable to modern MC lenses.

This is only the last 4/5 years and I began looking at how negs from my Coated lenses compared to the MC lenses

I'm not happy using my first un-copated 1931 Tessar, it is flat,much worse than my earlier Tessras which use different glass. By chance I bought 150mm Tessar cells off this forum, T coated, this lens won't flare in conditions where a High end digital SLR MC lens is useless.


That's why I'm so surprised you have issues with these lenses, sure they aren't the sharpest unless stopped down nto f22 but they are comparabple in terms of tonality to a more complex Symmar/Sironar etc.

Ian

TheDeardorffGuy
24-Aug-2011, 19:44
I'm a bit confused. All lenses will print differently. There was a time that Nikon said their lenses were color matched. (any one remember that statement by Nikon?)
I've never had a Kodachrome from any of my Nikkors match each other. Why would you expect your LF lenses to match? I just accept the fact the lenses are different and require different grades of paper. Of all the lenses that I have my set of uncoated Dagors seem nicely matched to each other and I can get nice prints on a 2 paper. Of my WF Ektars I have a 135mm that is a dog. It is clear, it is a very early one 1945. It is low contrast and always needs a 3+paper. Knowing your lenses is part of the experience. They all have different characteristics

IanG
25-Aug-2011, 00:07
I think the point I'm making is the differences between an uncoated lens such as your 1945 Ektar and one of my pre-War Tessar's compared to modern Multicoated lenses is quite large in terms of contrast etc with B&W. Colour is a seperate issue.

There's a huge step change between pre WWII uncoated and a post war coated lenses in terms of contast and tonality and far less difference between coated and Multicoated.

Yes there will be small differences in lens characteristics but in the case of a coated CZJ Tessar compared to a modern MC lens this should be very slight, certainly a very slight effect on contrast and tonality.

Ian

TheDeardorffGuy
25-Aug-2011, 05:12
I think the point I'm making is the differences between an uncoated lens such as your 1945 Ektar and one of my pre-War Tessar's compared to modern Multicoated lenses is quite large in terms of contrast etc with B&W. Colour is a seperate issue.

There's a huge step change between pre WWII uncoated and a post war coated lenses in terms of contast and tonality and far less difference between coated and Multicoated.

Yes there will be small differences in lens characteristics but in the case of a coated CZJ Tessar compared to a modern MC lens this should be very slight, certainly a very slight effect on contrast and tonality.

Ian


Actualy my WF Ektar is coated as are ALL WF Ektars. When Ektars (Not to be confused w/ WF Ektars) were called Kodak Anastigmats they were uncoated. Besides the history lesson I understand you. I have never thought of a Zeiss Jena as a true Zeiss lens. Being east german and all, there were some eastern bloc optical techniques snuck in the coating methods. Ever see a 12in 4.5 CZJ with a distinct golden colored coating? These simply will not take a good picture on color film. On B&W I can use every grade of paper I have to get a good print depending where I pointed my camera. (Sun direction) The Pre war Tessar by Zeiss Stugart is a great lens.

GPS
25-Aug-2011, 05:25
...
Ever see a 12in 4.5 CZJ with a distinct golden colored coating? These simply will not take a good picture on color film.
...

Good grief, don't be naive. Lens coatings don't have a color in themselves, they are clear. The color you see is a reflection caused color effect invisible on a taken photograph.

BrianShaw
25-Aug-2011, 06:32
... but I have a niggle, (a gut feeling).

~snip~

Thanks for including a definition... I didn't know whether to be racially offended, or start passing the hat to improve your financial situation. :D

IanG
25-Aug-2011, 09:55
Actualy my WF Ektar is coated as are ALL WF Ektars. When Ektars (Not to be confused w/ WF Ektars) were called Kodak Anastigmats they were uncoated. Besides the history lesson I understand you. I have never thought of a Zeiss Jena as a true Zeiss lens. Being east german and all, there were some eastern bloc optical techniques snuck in the coating methods. Ever see a 12in 4.5 CZJ with a distinct golden colored coating? These simply will not take a good picture on color film. On B&W I can use every grade of paper I have to get a good print depending where I pointed my camera. (Sun direction) The Pre war Tessar by Zeiss Stugart is a great lens.

The early 1950's CZJ 150mm T coated lens I have is identical to the pre WWII version released in 1938, one of the first coated lenses available. As the Zeiss optical works was in Jena you don't find pre WWII German made Zeiss Stuttgart marked lenses. In fact the only pre-WWII non Jena Zeiss made lenses are Zeiss (London) and were made just before WWI.

I've used quite a few later East German coated lenses and never had issues with colour or contrast, their coatings were very good by the 60's. Earlier coatings from most companies gave a blue cast and needed a warm up filter, they largely went out of use with Multi coating.

Ian

TheDeardorffGuy
25-Aug-2011, 11:23
The early 1950's CZJ 150mm T coated lens I have is identical to the pre WWII version released in 1938, one of the first coated lenses available. As the Zeiss optical works was in Jena you don't find pre WWII German made Zeiss Stuttgart marked lenses. In fact the only pre-WWII non Jena Zeiss made lenses are Zeiss (London) and were made just before WWI.

I've used quite a few later East German coated lenses and never had issues with colour or contrast, their coatings were very good by the 60's. Earlier coatings from most companies gave a blue cast and needed a warm up filter, they largely went out of use with Multi coating.

Ian

I have a 1938 Tessar too! 250mm. Simply a great lens. That blue cast ruined a bunch of 4x5 chromes I shot. I had a 150 Post war 1946 I think, I took the lens to PMA where Zeiss had a huge display and a genuime Optical Engineer. We spoke coatings and their effect on different films. Some coatings like a single layer of Mf2 will be the best all round for every film. Then the MC aimed at color and any sun angle. I told him about my "gold/ yellow CZJ lens. He asked me if I had a method of measuring transmission Stops. I do . He suggested that I measure it. That lens had a T stop of 6.7. Same lens uncoated was 4.8. Both were 150mm 4.5s

GPS
25-Aug-2011, 12:05
I took the lens to PMA where Zeiss had a huge display and a genuime Optical Engineer. ... He asked me if I had a method of measuring transmission Stops. I do . He suggested that I measure it. That lens had a T stop of 6.7. Same lens uncoated was 4.8. Both were 150mm 4.5s

The lens in question did not loose the transmission thanks to its coating, that's for sure. Coatings increase the light transmission...;)

IanG
25-Aug-2011, 12:35
I have a 1938 Tessar too! 250mm. Simply a great lens. That blue cast ruined a bunch of 4x5 chromes I shot. I had a 150 Post war 1946 I think, I took the lens to PMA where Zeiss had a huge display and a genuime Optical Engineer. We spoke coatings and their effect on different films. Some coatings like a single layer of Mf2 will be the best all round for every film. Then the MC aimed at color and any sun angle. I told him about my "gold/ yellow CZJ lens. He asked me if I had a method of measuring transmission Stops. I do . He suggested that I measure it. That lens had a T stop of 6.7. Same lens uncoated was 4.8. Both were 150mm 4.5s

What surpries me about the blue Zeiss coatings is just how good they are, I've used my Tessar shooting into the sun on a Crown Graphic with no flare or loss of contrast, also with a 75mm f8 coated Super Angulon on my 6x17, at the same time the zoom on my Canon DSLR was flaring so badly it couldn't be used.

I used a CZJ Pancolor on a Prakticamat in the 70's and that was fully colour corrected hence the name, the coatings optimesed to give no colour casts. I have another Pancolour on an Exacta Varex IIb and that has the more golden/yellow coatings you mention and I'd guess thats the same coatings used on other later (pre MC) CZJ lenes.

Ian