Tilt for P67: reflections

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Hi after several weeks of research, I have come to the conclusion that there's no way to have a tilting wide angle lens on a P67. I have found various possibilities, none of them fullfilling my needs of landscape photographer who would like to sometimes take advantage of Scheimpflug's rule.Here they are.

Homemade adapters with LF lense: The ones homebrewed by Peter and Claudio recently seen on this forum. I appreciate their work but in my case I don't feel like this is a viable approach since in the best case I will end up with a moderate telephoto lens (best is Claudio's approach with the Bronica adapter: 127 mm focal lenght). And still I have no idea who could help me make the accurate mechanical work needed.

Commercial adapters with LF lense: There are two: Horseman and Zoerk. The first seems very costly and has the same limitation above seen (min.focal lenght 135 mm - not completely suitable for landscapes). Zoerk looks like the best compromise around even though it would still cost an arm. I inquired them and the response was a modified 105 mm enlarger lense on a modified (MFS) tilt adapter, all for 2500 DM + VAT (still the cost of a simple large format system). I wonder if there exists a LF lense in the 60-70mm range with an augmented distance of focusing that could allow the use with the Pentax.

Tilt & shift lenses: Looks like Pentax is the only one in the 6x7 arena that is not going to put out a tilting lense: Bronica after all have the tilting bellows and Mamiya RZ have a limited choice of tilt&shift lenses. Recently I have found a new T&S lense by Hartblei (http://www.hartblei.com/products/lens.htm) suitable for Mamiya and COntax 645. I inquired them they say if I found a Pentacon6/mamiya645/Contax645 to P67 adapter there's no problem. Instead I think there's a big problem first of all from the distance from the bayonet to the film plane (85mm for P67, 82 mm for Hartblei lense) and second the angle of coverage might not be sufficient for tilting at 6x7 (the lense seems to be made for lower formats like 6x6 or 6x4.5).

Any comments or suggestions to this list? Is a LF system the only way to go?

Regards Roberto

-- Roberto Manderioli (ik4jqw@amsat.org), February 17, 2001

Answers

Roberto, it sounds like you are concerned with that long standing problem of DOF in the P67 and that looks like why you are looking at tilt capabilities. Regarding your question about a LF lens in the 60 to 70mm range that has enough back focal distance to clear the mirror on the 67; it is highly unlikely to find one. LF lenses are mostly Plasmat and Biogon designs or modifications of these. They are symmetrical or nearly so and are that way to give the designer more ease in correcting all aberrations. Only the LF telephotos deviate significantly from symmetry. Joachim's idea of a LF camera with a 67 back or 2x3 is a good one. They are not for everyone however. I used a flat bed Linhof in Fiji for a few shots and found it to be difficult due to its slowness when lighting changes occured in the scene. Focusing on the ground glass, even with a loupe is not easy. You would have to try one of these cameras to decide. Another solution to the DOF problem in the 67 is to use lenses with smaller stops(75 shift- f/32; 55-100 zoom- f/32; 135 macro-f/32; 165 LS-f/32). SR

-- Steve Rasmussen (srasmuss@flash.net), February 17, 2001.

One more thought on this subject. Pentax needs to make their Auto Bellows with tilt, etc like Mamiya does. Several of the lenses can be mounted in reverse to retain infinity focus. Pentax could even make a couple of lenses specifically for the bellows. SR

-- Steve Rasmussen (srasmuss@flash.net), February 25, 2001.

Pentax should indeed make several tilt lenses, especially in the focal lengths where DOF is a real problem. I would like a 150 or 200mm tilt. The cost will be high not only because of the tilt mechanism but also because of optical considerations. Using the lens far off the optical axis requires the use of ED glass due to lateral chromatic aberration. One can see the difference in design between the 75mm and the 75mm shift. Several more elements are needed to fully correct the image when shifted. Notice the difference in cost on these as well.

-- Steve Rasmussen (srasmuss@flash.net), November 10, 2001.

Roberto, I recently added a 6x9 LF camera to my Pentax 67 system for the purpose of shift and tilt in landscape photography. I acquired the so called Linhof study camera 70 which is the latest Linhof Technika without rangefinder (produced from 1964-1971) with a 6x7 roll film back and a mid 1980 Symmar-S 5.6/100mm. By the way, the whole outfit in mint condition was less than half the price of a new Pentax 67 shift lens. Total weight is about 2.5 times the Pentax shift lens.

My experience after exposing the first ten films is the following: 1) the optical quality of the Symmar-S is very similar to the one of my 2.8/90 Pentax lens at my usual working apertures 16/22. 2) I use the shift feature in landscape photography much more frequently than I originally expected. 3) It takes time to become comfortable with the reversed image on the ground glass - coming from the Pentax 67 world I still have some trouble. 4) Probably the most important point for you: forecasting the effect of lens tilt is extremely difficult on the small 6x9 ground glass at maximum aperture 5.6! I think I will need much more experience until I can obtain exactly the effect I would like to achieve. But I am a beginner in LF photography. 5) Photography with the Technika is pure fun. I enjoy it very much but I would not trade my Pentax 67 for it. It is a nice combination which you might consider for your purposes as well. Best regards,

-- Joachim Inkmann (Joachim.Inkmann@uni-konstanz.de), February 17, 2001.


Steve and Joachim: I agree with all your points, there's no way to have perspective control on the P67, in one way or another you have to consider different systems. Steve: the reasons you have mentioned about the Linhof is what really is keeping me from purchasing a LF system. I know I would loose many shots due to the slowness of the setup, that's the reasons I was trying hard to find a solution in the P67 world. I hope that in the future someone will put out something useful for this purpose. At least Pentax should provide their normal wide angle with f:32 minimum apeture as Steve said (the 75 shift and 55-100 zoom are way too heavy and costly). Thanks for your help Ciao

Roberto

-- Roberto Manderioli (ik4jqw@amsat.org), February 18, 2001.



After louping my friend's chromes I bought the 55-100mm zoom that spares my much beloved 55mm/f4, the sharpest P67 lens by far in my line up excellent at ALL apeture settings, something seems to defy the physics which was my major. Since I have found the zoom has great contrast, surperb resolution, minimal distortion and flares, and actually a little bit wider than the 55mm/f4 at the extreme. It balances very well on the 67II body dispite the weight and size. Also the minimal f/32 apature makes the DOF problem a bit easier to handle, and over the long focus length range the zoom is much sharper than my 90mm and 105mm at f/22 and f/32 (not available with the primes).

I took the chance to take the 55mm/f4 apart since I have some mechanical background, and found I was able to insert a hard rubber spacer to make it to have a fixed down tilt of about one degree, at the orientation I usually go to in shooting verticals (the camera top to the left). The little tilt tend out to be mostly adequate in the near-far composition situations, if the camera is at my eye level. Sometimes it is over tilted, which was easily handled with DOF since the image quality from this lens is so good at f/22. As some mentioned in photo.net the P67 lenses has in general very wide coverage enough to be used for 4x5, so the little tile induced no problem at all in terms of sharpness and uniformity. Unfortunately I do not see the same possibility with either the 45mm/f4 or the 75mm/ f4.5, since with any tilt/shift/swing the rear barrel will touch the mount.

We should loby Pentax to make a tilt version of the 55mm/f4 since from what I learned it is possible and relatively easy to do. I have been since conceiving an alternation piece to make the tilt adjustable but so far had no good designs since the tight spacing. Anyway with the built-in tilt in my 55mm and the f/32 ability of the zoom I am basically happy with the system now.

-- Leping Zha, Ph.D. (leping@tamri.com), November 09, 2001.


Lephing: first of all congrats for your excellent and enviable skill in disassembling lenses, something I am very scared of ! I ended up buying a 4x5 sistem to solve my need of tilt&shift but still have the P67 system and still look for compromises to bring tilt ability on my MF system . In fact the LF gear is very bulky heavy and slow although very flexible and capable. Having the tilt on the 55/4 Pentax would be a real dream, if Pentax did that it would be a killer lens although I am very afraid the cost would be still higher than a complete 4x5 sistem... Thank you for your post, very interesting Ciao

-- Roberto Manderioli (ik4jqw@amsat.org), November 10, 2001.

But 150 or 200 is long enough for the Zoerk or VCC adapter with a LF lense, if you can afford it it might be a solution....

-- Roberto Manderioli (ik4jqw@amsat.org), November 10, 2001.

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