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440 FLE v 440 IF


New Member
Have to opertunity to purchase a 4/40 FLE or 4/40 IF on the used market -- both are CFE lenses and mint condition (10-). The IF is quite a bit more, but have not seen a discussion of the IF -v- FLE. Both seem to be recent designs, why the update?

I have seen some discussions of flare, but could not see to which lens it was attributed.

Thanks, Hugh
The IF wins hands down. You can see the MTF charts on the Hasselblad web site. The IF is very hard to find on the used market. I ended up getting the FLE version.
The IF is sharper (not that the FLE is not sharp enough already ;-)).
The IF also shows more distortion.

So it depends on what you think is more important.
I'm considering either a 40mm CF f4 FLE or an SWC. But I have not before seen the term "IF" as used here, is this the non-FLE design / version of the 40mm CF lens (non-floating lens elements)?

My understanding was that the FLE version was superior to all other 40mm versions ( C and CF) in that the FLE helps ensure critical sharpness at infinity.

I have a 50mm CF f4 FLE and it is just superb!

Is the 38mm Biogon (SWC) that noticeably better? Is there that much less distortion edge to edge? If the film plane is level to the subject, is the 40mm free of geometric distortion?

Thanks for helping.

The IF version is a newer version, introduced a few years ago. Newer than both the FLE and even older non-FLE versions.
It uses internal focussing, hence the "IF" designation.

The IF version is a lot better than the FLE version (which indeed is better than the non-FLE version), except (!) as far as distortion is concerned.
Distortion figures have doubled, compared to the FLE version.
Resolution of the IF-version on the other hand is at a really unbeatable high level.

(The FLE version, by the way is the only CF version; the CF version and the FLE CFE versions are optically the same.)

The Biogon has extremely low distortion for a lens of this focal length.
Neither 40 mm version can match that, with the IF-version lagging very far behind.
So if distortion is important to you, don't get the IF, get the Biogon.
Thanks Qnu. Yes the IF designation threw me as I was aware of the CFi version's incredible resolution.

For my purposes I'd prefer lower distortion than improved resolution especially since these Zeiss lenses don't really suffer from weak resolution!

I see from distortion graphs that the Biogon is substantially better than the 40mm CF FLE. So, I am assuming that because camera shooting angles can add their own distortion (super sensitive wide angle lenses), I'd be a long way better off with a lens with absolutely minimal pincushion or barrel distortion. Do you agree?

With regard to the 38mm Biogon SWC - are the optics exactly the same in all T* versions?

Do the C T* and CF versions differ much in resolution and other traits like flare?

I know about the "camera body" differences which don't really matter to me, but want to be sure that there are no optical differences.

"Pin cushion" or "barrel distortion" and "wide angle" distortion are two separate things.
The first is a fault in the lens' projection geometry, the other is the result of the angle of view.
While you can get rid of the first, the latter is impossible to avoid with lenses that having large angle of view.

But yes, i agree that in this case the lowest distortion would be preferable over the highest resolution, since adding extra distortion certainly doesn't help, and the resolution of the 38 mm lens is more than high enough already (you rarely ever use the high resolution of these lenses fully anyway).
But don't expect the Biogon to be less "sensitive" to wide angle distortion.

The optics of the Biogon remained unchanged from 1954 until the 905 appeared a few years ago with a redesigned Biogon.
The redesign was made necessary because of environmental restrictions on what glasses could be used.
The redesigned Biogon on the 905 differs in performance from the older lens, but only a tiny bit (which is quite remarkable, since the original design was made in the pre-computer era, while they will have used brute force computing to design the new lens. Shows what a good job the original design is). The resolution in the center is slightly less, while that in the corners was improved. Overall, i think, not a difference to worry about.

So all the versions since 1954 are equal as far as resolution and distortion is concerned.

And all the T* versions are the same as far as coating are concerned too, no matter whether C, CF, or CFi.
The CFi version promises to have better internal baffling, but i doubt that this is very apparent in the Biogon.
Many thanks Qnu.

Yes I understood that pincushion/barrell distortions are lens design/build issues while "wide-angle" distortion is user created by angle of view and film plane relationship to the subject.

My main issue between the 40mm CF FLE and the 38mm Biogon/SWC is one of relative in the field performance - and I think that you have confirmed my view that the SWC is preferable to a 40mm because there is virtually no built-in distortion. So for not a great deal of price difference an SWC may make a better buy.

For my intended use, the elimination of built-in optical distortion is vital.

However, my most important question is this: since using an SWC means you don't see what you will get, is it easier to avoid "user created wide-angle distortion" with a 40mm CF FLE because you can see what you will get?

I have no fear of using a rangefinder style camera and am happy to shoot most of the time on a tripod and use the spirit level to be sure I don't add/create distortion.

I just wonder if users find that they don't get 100% of the Biogon great design benefits because they cause "user created wide-angle" distortion anyway, which they help avoid with an SLR's WYSIWYG (despite the 40mm FLE's own built-in barrel distortion compared to the Biogon)?

I hope I've been clear here. Thanks for helping me out.

The new 40 IF is an amazing lens.
It performs better than 40 CF(E) as far as resolution goes,is easier to use and is a must for work with high grade digital backs.
The small increase in distortion is easily corrected in digital post production.

My general rule as far as lenses goes:

Silver lenses old design show their limits on film:

CF lenses old generation show their limits on high grade digital backs.

For digital application the 40 CF IF and the 120 CFE are best suited.


I have not used it with an H1 or H2, but I can tell you that the IF makes handling this substantial lens easy to focus and Zeiss states that it is well suited for digital! It is one of my favorite lenses.


I can't find any clue about IF glass. When you say CF IF glass, do you mean CFI?
In that case, is CFI, a FLE design too?



PS. I responded 3 times to your screen adapte offer. Have you got any of my responses?
I am interested on buying your screen. Please email me directly. Thanks.
>[I hope this combo is not good (LOL) as it is something i have >considered for a long time but it is a costly set up and >----somewhat of a pain to use]

A few years ago, a new 40 mm Distagon design, with Internal Focusing = IF, was introduced, to coexist alongside the 'old' 40 mm FLE Distagon.
The fact was well advertised, and you should indeed find info about it on the web (Zeiss, Hasselblad, etc.)
Hi Mark - As you can see, I have not given up on the CFE IF. Problem is, everyone says it is one of Zeiss's best wide angle lenses, equal to or better than the Biogon, but there is no info out there on using it with the H1/H2.

With regards to it being a "pain to use," I agree in part when you compare it with HC glass. However, in terms of landscape photography, I'm use to long set-up times and it does remind me of my very pleasant days with the V series cameras/PME/film.

Another problem is that it seems impossible to find this lens used (or for rent in Southern California}. Either people love it so much that there is no interest in selling or there are very few to go around. I suspect the former.

The entire issue still remains open and I will continue to seek answers before I decide one way or another.

BTW, I am fully aware of the distortion issue, but don't believe that will be a problem here.
>Martin if you try it and like it exclude me from that email..LOL . >i think the lack of used lenses is a combination of both the reasons >you have outlined. I think I have seen one or two on ebay and the >slight discount for a used one was not worth it in my mind. At this >point, even if there are rave reports, it would be hard for me to >justify the cost at this point especially since i sold my adapter. >I am curious about the results though. I think you should bite the >bullet and try it out and report back to us...
I just wonder why Hasselblad stop making the IF series glass if this is better "tuned" for digital. (please somebody tell them to reconsider).

From most everybody's input, it seems a better companion for digital backs and software PP.