wide angle lens advice

[cs_foto]

yes indeed, burning down the house...

I have a 50mm CF which I'm not very happy with in terms of distortion, it is awful in that respect, appart from that: great, sharp, contrasty etc..

now I could get a CF 40mm, I really don't care for the wider angle, i could work with either of them.. will the 40mm be better in regards to distortion?

 

[polypal]

Be it C or CF the 50 mm Distagon, non FLE of course, has only 1,2 % barrel distortion.
I think you are not talking about distortion but about change of perspective with these WA lenses.

Change of perpective is a physical matter and has nothing to do with distortion.

 

[cs_foto]

well I'm not really sure what you mean by change of perspective (to do with converging lines?)

take this image for example, I am really upset at how the tower tends to lean to one side, plus it is a bit barreled as well....

I know the way around this is with view cameras, but I have seen the Mamiya 43mm on a rangefinder (mamiya 7) and it is outstanding, I am looking for something like that...

thanks for your answer

 

[bensonga]

...but I have seen the Mamiya 43mm on a rangefinder (mamiya 7) and it is outstanding, I am looking for something like that...

I don't know all the technical reasons why, but from exchanges I've had with folks on the GetDPI forum about various wide angle lenses on medium format cameras.....you won't be able to get distortion free results like the Mamiya 7 43mm lens with any lens designed for a medium format SLR camera. I have the 40mm IF and 50 CFi for my Hasselblad and the 45mm and 55mm lenses for my Pentax 67. From everything I've read, as good as these lenses are, they just cannot compare (re lack of distortion) to the 43mm rangefinder designed lens on the Mamiya 7.

I'll see if I can find the posts and technical explanation on why this is the case and (if there are no objections), post it here.

Or maybe someone here with more technical expertise than I can comment.

I had actually wanted to pick up a Mamiya 7 system with the 43mm lens just so I could do a "shoot out" between it and my Hasselblad 40mm IF and Pentax 67 with the 45mm lens. Maybe someday that dream will come true!

Gary
Alaska

 

[vandevantersh]

I'll see if I can find the posts and technical explanation on why this is the case and (if there are no objections), post it here.
*********
I think the "problem" is related to the mirror box and the need for retrofocus lenses. from wiki:Since the 35mm single-lens reflex (SLR) requires a space for the reflex mirror, it imposes a limit on the use of wide-angle lenses of normal designs, unless the reflex mirror is locked in the up position. The Retrofocus lenses addressed this situation by making wider lenses usable while retaining normal viewing and focusing.
*******
If you buy an SWC instead of the 40mm, it won't be a problem.

Steve

 

[polypal]

If you buy an SWC instead of the 40mm, it won't be a problem.

Steve

Perpective distortion stays and has nothing to do with the fact that all lenses starting with the 80 mm
downwards with a SLR Hasselblad camera are in fact retrofocus.

If barrel distortion is a problem get yourself an SWC.
That camera/lens has only 0.1 distortion, about the best you can get in that kind of WA.

The new 40 mm IF lens has over twice the amount of barrel distortion the old 40 mm CF(E) had.
Even without digital corrections that lens is considered a very good lens despite its 2,5% barrel distortion.



Paul

 

[michaelhcothran]

take this image for example, I am really upset at how the tower tends to lean to one side, plus it is a bit barreled as well....

I know the way around this is with view cameras, but I have seen the Mamiya 43mm on a rangefinder (mamiya 7) and it is outstanding, I am looking for something like that...

I feel you might be comparing apples to oranges in the way you are assessing the Zeiss 50 and Sekor 43. In your posted image, I see the light house lines converging inward, indicating that your wide angle lens was pointed upwards. The only remedy to this problem is a shift lens. All wide angles, including the Mamiya 43mm will yield similar distortion under the same circumstances.
FYI - the Mamiya 43mm lens is actually a copy-cat design of the Zeiss 38mm Biogon, found in the SWC series cameras, which is why it performs so well at the edges. If you are trying to stay with Hasselblad V system lenses, perhaps one of the SWC bodies is what you need.
Barrel distortion on Zeiss wide angles is very much controlled - more so than with most off-the-shelf wide angles.