new 40 CFE IF versus 903 SWC

Discussion in 'Medium Format' started by fabio_scaglione|1, Sep 28, 2003.

  1. Has anyone compared the new 40 CFE IF versus the Biogon 38mm of 903
    SWC? what about quality? Contrast, sharpness, distorsion.... Dear
    Kornelius, to you the first answer.
  2. its really good,

    in a previous thread it stated that the lens resolves to 200lp/mm

    with lower distortion on the edges of the frame than the 40 cfe..

    which means... if this is all true, i will be dreaming of a dream that won't come true for me without saving up for at least a year...


    i think kornelius mentioned that he is going to do a write up and post the article in the zeiss articles.. last time i checked, it wasn't there.

  3. cpj


    This is a no-brainer to anybody who has used both. The 40 mm lens alone is as big and
    weighs as much as the 903SWC. It's not even a jump ball. Get a 903 and you can carry the
    whole camera, back and lens around like a tourist and shoot at 1/125th sec. hand-held and get
    reasonable results. I don't think ANYBODY who owns a 903SWC would give it up in
    exchange for a 40 mm (although BEFORE trying both I did have the same question and it was
    quickly answered.)
  4. Frederick,

    You wrote: "with lower distortion on the edges of the frame than the 40 cfe.."

    This is not so. On the contrary:(according to Zeiss supplied figures) distortion has in fact increased by a factor 2, comparing the new lens to the old 40 mm CFE.
  5. I tried a 903SWC and a 40CFE (non-IF)and there was no contest. The inaccurate, distorting finder in the SWC where you see the lens instead of the lower half of the frame was simply horrible to use. I tried using the GG back and a finder but going to all that trouble I might as well just use a 4x5. Optically I couldn't see what all the fuss was about the Biogon. I shoot landscapes, not architecture--but if I did, rather than go to the trouble of the SWC I'd once again go to a 4x5 with movements. I'm sure the 40 IF is a better lens than the CFE, though I'm not sure how much. What I am sure of is that given the plummeting prices on used Blad, I would have to be nuts to buy anything new in Blad let alone the 40 IF.
  6. Such a new lens, I doubt anyone but Kornelius will have had the chance to
    compare them both.

    I am considerably less negative than Jay in my feelings about the SWC. I
    have the 905SWC and I think it is a great camera. There may be other
    cameras with lenses having similar focal lengths and even similar resolution,
    but none of them are in a package as compact as the SWC. The prism at the
    bottom of the SWC finder is there to allow you to view the top of the lens so
    that you can set focus, shutter speed and aperture without your eye leaving
    the viewfinder. In use, I think it is helpful, although someone used to the
    waist-level viewfinder of a 500/200 series camera might not be used to it.

    There was a post earlier addressing this very question. The gist of it was that
    the 40 IF was better than the 40 CFE, but not better than the Biogon.
  7. Sorry I have not compared the 40 CFE IF with a 903. But I have owned a 40CFE and sold it so fast I did not like to results of the lens. I have purchased a 905SWC and it is a excellent

  8. I like the SWC so much I have two: C T* (which I prefer: more compact and the coupled speed/aperture) and a CF. Unsurpassed performance, even ALPA chose to use one for their new camera.

    Classic design, not improved with the 905. Although, Kornelius claims a better body.
  9. hmm...i think kornelius posted something that the distortion figures did increase but the distortion that we are worried about (well i am) is the edge distortions, and i believe he said it actually improved..

    but then again, i may have misread his thread... he posted a month back? maybe i can find it again...

    anyhoo...he said he will be writing up an article on regarding the new 40mm
  10. Frederick,

    [...] but the distortion that we are worried about (well i am) is the edge distortions, and i believe he said it actually improved..

    The big question however is why the distortion figures provided by no other than Zeiss don't show that. On the contrary, they show that edge distortion too is far worse than that of the predecessor 40 mm Distagon model.

    True, the distortion graph is leveling of towards the edges/corners of the frame, and a displacement of 3.x % of 40 mm is less than a displacement of 3.x % of 30 mm.
    But the distortion seen in the predecessor model was less than half that to begin with, and did actually decrease in the same region it remains constant in the new lens.
  11. Now, let me contribute two comments on this subject:

    If you want a super wide angle lens in your Hasselblad system and you need SLR viewfinder control in the type of photography you do, then the Distagon 4/40 IF is your best choice.

    If you can do without SLR control, the SWC with the Biogon 4,5/38 is a very attractive alternative. With the SWC you can focus even closer - considerably closer - than with the Distagon IF.

    In terms of optical performance, mainly sharpness, the Distagon IF comes far closer to the Biogon than any Distagon 40 before. According to my test results, the sharpness of Biogon 38 and Distagon 40 is about equal. At least in practical photography. Both offer a resolving power of 200 linepairs per millimeter in the center of the image on Agfa APX 25 film (yes, I still have some of these). Under lab conditions the Biogon is still ahead. Especially very (!!!) close-up.

    There is, however, at least one performance aspect where the Distagon is visibly superior to the Biogon: Field illumination is clearly more even. You will notice this especially close-up, shot wide open, where image corners of Biogon shots come out darker than the respective Distagon 40 IF shots.

    In the commercial photo studio where product shots are made with digital backs, I would clearly prefer the Distagon IF on a Hasselblad 555 ELD.

    Distortion is a different matter. My two-part answer: The Biogon is still the undisputed king in this respect. Period.

    But then, how does the Distagon 40 IF compare to its predecessor?

    Several of you answered this question, based on official Zeiss distortion diagrams, but with no practical experience of your own with both lenses.

    What do those Zeiss distortion diagrams actually tell us? Let us imagine for a moment there was a lens with a diagram that gave the distortion as minus 5% over the entire field. Would this be a horrible lens with grossly bent lines, bent as ugly as seen with TV-news lenses? Far from it! The images from this lens would be perfectly free from any bending!!! Minus 5% in a Zeiss distortion diagram means that the effective focal length for this point of the image is 5% shorter than the nominal focal length of this lens. So, minus 5% on a graph for a 100 mm lens means, that at this 5% point, the lens would image/position a subject detail like a 95 mm lens would.

    In other words: In the Zeiss distortion diagrams the regions of significant bending of straight lines in the image are not the ones characterized by values which are far away from zero, like minus 3 or plus 2, rather, bending occurs in the image where the graph is bent itself.

    Now back to the 40 IF vs. FLE comparison: In the 40 IF image there is a region where bending does occur, even more so than in the images from a 40 FLE. But it is far away from the edges of the image which usually act as a reference for straigtness and is therefore less obvious than bending in images taken with the 40 FLE.

    We at Zeiss could have reduced this bending significantly, had we, and Hasselblad, allowed our lens designers to increase the lens front diameter by an inch or so. Hasselblad wanted to maintain the front diameter, and for good reason, as everybody understands who follows the discussion about the huge new AF-zoom for the Rolleiflex 6008 AF on this forum.

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