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View Full Version : Zeiss Biogon 38/4.5 for Large Format???



Sol Campbell
12-Jan-2001, 04:51
Hi,

A while ago I posted a question about a modern T* Zeiss Planar lens for sale on E-Bay. The seller, Kerry Thalmann was very nice and gave a complete history for that lens. That lens by the way went for $3K!!!

Well I have spotted another one! This is the Biogon 38/4.5 in a Copal shutter fo r sale. Actually I have found two places for selling this one at around $1000-$1 500. I wonder if this is the same one as in the Hasselblad SWC.

I did not know that Zeiss sold this lens in a Copal shutter for the view camera market. How does one get one?

I am curious! Can Kerry or anyone else enligten me?

Thanks!

John O'Connell
12-Jan-2001, 08:01
I don't know about the 38 Biogon, but the 75mm version isn't supposed to have the biggest image circle -- I've heard it's just sufficient for 4x5. Therefore the 38 might be marginal for 6x9 at infinity.

If I had to guess, 38mm would be a good wideangle length for a 2x3 Technika and I would assume these are lenses originally produced for that camera. Nowadays a 35mm Grandagon might be a better choice.

Sol Campbell
12-Jan-2001, 18:13
John,

Thanks but I am not after the lens for myself. I am a big Zeiss fan but I just wanted to know more about it for the sake of knowledge!

So if anyone know about it please let me know!

Thanks!

John Hicks
13-Jan-2001, 03:14
The 38 Biogon has fairly recently become available in helicoid mounts for the Al pa 12 6x9 camera; I gather it just barely covers sufficiently.

While the Biogon is a fine lens, a 6x9 view camera user would probably be bett er served by the Rodenstock 35 lens.

Trevor Crone
13-Jan-2001, 05:13
Sol unless you are really determined on the Biogon 38. I would seriously conside r the 35 Apo-Grandagon. I use it on the 69 format and its a first class lens all owing some movement to boot. Regards,

Sol Campbell
13-Jan-2001, 05:26
Trevor,

Thanks for the info. But as mentioned before I am just after the knowledge. I am curious. Of course I know of the Apo Grandagon 35/4.5.

But for you information, while the Apo Grandagon 35/4.5 may be one fine lens the Biogon puts it to shame, albeit with a smaller image circle. The 38 Biogon is one of the finest lenses ever made by Zeiss and if you compare the MTF curves of it aginst the Rodenstock, you will see the differnce - night and day and know what I mean.

Thanks again!

Julio Fernandez
13-Jan-2001, 14:07
Sol: I am big Zeiss fan too, but the comparisons between the MTFs for Apo Grandagon 35mm and the Biogon 38mm need corrections. First, the Apo Grandagon made for the Hasselblad is not the same lens than the one made for LF. -Reflex lenses must pay a heavy retro-focus tax, and the A-G pays a heavy one in the Hasselblad version. Yes, it is mindless or at least unimaginative for Hasselblad and Rodenstock to call the Hass. version an A-G, when it bears no ressemblance to the real A-G for LF. Comparing the Hasselblad versions, yes, the Biogon has the better MTFs albeit a reduced IC. If the comparison is between the LF A-G and the Biogon, that is another story: Here, the A- G is by far the superior lens. I am sure even Zeiss would agree. In this case, though the comparisons need to be made at optimum apertures for each lens, being mindful of the respective ICs and using the same L/mm as the base point. (20L/mm is given for both) The A-G just covers the 9X12 European format, the Biogon barely covers 6X6. The answer to the question with regards to LF is that the Apo-Grandagon is without doubt the superior lens. I have to wonder why anybody other than a museum curator would pay such an exorbitant sum for a lens for which in LF at least, there are far superior alternatives. This is one case where reading the MTFs correctly can save lots of money.

Glenn Kroeger
13-Jan-2001, 14:56
Julio:

Where do you come by this info on the A-G for Hasselblad. As far as I knew, the only Hasselblad version is for the ArcBody, which due to the lack of any mirror box, does not require retrofocus designs, but rather uses Rodenstock LF lenses to handle shifts and tilts.

Sol Campbell
13-Jan-2001, 15:13
Julio,

Sorry but you are very, very wrong. The Apo Grandagon for the Hassy is identical to one for view cameras. It is NOT for the SLRs but the Arc Body (which has no mirror). If it was different then it would not be called the Apo Grandagon, but something else. It would also be a tottaly different beast, since it would have to be non rectilinear.

Moreover, the MTF curves published by Hasselblad and Rodenstock are the same, since it is the same lens. Of course Hasselblad does publish a 40 lines per mm curve which Rodenstock does not.

How did you come to the conclusion that the Hassy AG was completely different?

Thanks.

Glenn Kroeger
13-Jan-2001, 19:32
Sol:

Agree about the 35 Apo-Grandagon being the same in LF and Hassy... where did you get MTF curves for the 38mm Biogon?

Sol Campbell
13-Jan-2001, 21:13
Glen,

Zeiss are great to publish MTF curves for all their lenses. You can find them at www.zeiss.de. You can download a PDF file that is very nice and has a lot more info than just the MTF curves.

Also Hasselblad too publishes the MTF curves at their web site www.hasselblad.se.

Compare the two MTF curves. Like I said before, there is no comparison. The 40 line curve of the Biogon is as good as the 20 line of the Apo Grandagon!

The 35 Apo Grandagon is the poorest performer in the Grandagon series, according to the MTF curves. The 45mm really shines and that is much closer to the Biogon.

Thanks.

Julio Fernandez
14-Jan-2001, 01:45
Sol and Glen: The 38mm biogon MTFs come from Zeiss's site for the Hasselblad lenses. Those for the Apo Grandagon for the Arc Body come from the Hasselblad site. The ones for the Apo Grandagon, LF come from Rodenstock's own literature for the Grandagon lenses. My conclusion that the Grandagons Hass version and LF version were different is based on the totally different MTFs for the 35mm Grandagons as shown in the Hass site and in Rodenstock's brochure. On that basis, I can not see how the two could possibly one and the same lens. About retrofocus you are both correct, so the difference in performance needs another explanation. (Yes, taking into consideration such things as apertures, IC and L/mm, which can only be compared at 20L/mm since 40 L/mm is not given for the LF version of the Grandagon). Do check please, perhaps I missed something?

Sol Campbell
14-Jan-2001, 02:02
Julio,

If you look at both, you will see the that they are the same. It is not that easy, since Hasselblad publishes them at f4.5 and f11 and Rodenstock publishes it at f8 and f16. But by the shape you can conclude that it is the same.

Look at the shapw of the curves, which are quite unique. The performance at center is much poorer than half way through the image circle. And don't know a lot of lenses with this characteristic. But both the Hassy and Rodenstock curves do show this.

Moreover look go to:-

http://www.hasselblad.se/products/lenses/lens_roden/index.html

And look at the picture of the shutter! It is a Copal! So Hassy won't even give you an expensive shutter for what they charge!

So are you now convinced that it is the same lens?

:)

Julio Fernandez
14-Jan-2001, 13:22
Sol: Tabulating the numbers indicates the following: Radials for both LF and Hass versions of the A-G are identical but tangential lines differ, with the Hasselblad version being lower. Because the LF version gives f:/8 and f:/16, to make the comparison fair I had to average the two readings to come up with an f:/11 reading for the LF so that we can compare that with the f:/11 of Hass. (some license in so doing but close enough) Results for tangential lines taken at 0, 20, 32 and 40mm are as follows: LF version: 71.5, 74, 65, 52. For the Hass version: 70, 66, 58, 42. The last reading in the Hass is 20% lower than for the LF version. One difference could be that the Hasselblad readings are measured and Rodenstock's are calculated. However a 20% difference for one of the readings can not be neglected. I agree with you that the two lenses were not intended to be different, contrary to my previous statement, however, Rodenstock and Hasselblad have some unanswered questions here. No, I do not think that the copal in both is a sure indication of anything. On the second issue, the Biogon, the readings for the radials at f:/8 and 20L/mm compare as follows, again at 0, 20, 32 and 40mm. (The reading on the left is for the A-G LF, that on the right for the Biogon) 73/88, 75/88, 85/75, 72/30. Then as above, for the tangential lines: 73/88, 80/76, 72/65, 58/45. The above confirms that the Biogon is a good lens and only slightly better up to midway but beyond, the A-G is substantially better. As I said, the old Biogon for LF may be worth the money,... for museum curators. For the same money and LF, my choice would still be the Apo-Grandagon.