For many years Pentax has been accused of having optical problems when compared with other MF companies. There have been reports of the 300mm Takumar/Pentax of being hopelessly soft and that the 105 was no better than junk wide open and at f/4. Some have claimed that they have yet to get a sharp image from the 400 Takumar. Others have sold their entire P67 system because they felt the optics just didn't match other producers. My conclusion is this: Most claims of optical problems were actually caused by shutter vib. None of my eight lenses are junk wide open although the 600 will fringe quite easily given the wrong circumstances. Most of the perception of poor optics are actually the operator not knowing the limitations of the camera system. SR

-- Steve Rasmussen (srasmuss@flash.net), May 09, 2000

Answers

The shutter vibration causes a harmonic in the long lenses and tripod that is similar to a tuning fork. This just aggrevates the situation already caused by the linear motion of the shutter. SR

-- Steve Rasmussen (srasmuss@flash.net), May 16, 2000.

Yes, shutter vibration. But when you have a job to finish and do not have the ability to dampen the vibration (in fashion you mostly just don't have time) all that matters to art directors are end results. No excuses like "My lenses ARE pin sharp, it's just the camera..." I however still love the 67, although it has let me down several times now in terms of sharpness reduction via shutter shake. No problems otherwise, thank god, but I was forced to buy the 645n in addition to the 67 system and love it just as much. Been using the 67 lenses on it, yummy, and can confirm they really ARE pin sharp.

But my point is - what good is a sharp lens if you have difficulties using it, i.e. achieving it's optimum performance because the body literally jumps when the shutter trips?

-- Alex B. (samedobrefotke@hotmail.com), May 10, 2000.

The disappointing thing is that the Pentax engineering staff doubtless think they've already answered this problem with the shutter/mirror improvements in the 67II body. I bet they even had some lengthy discussions about whether to try increase flash sync versus concentrating on quieting the shutter during the design process. For all the improvements, though, the results of the shutter redesign are pretty disappointing when compared to the current state of the art. Top of the line 35mm SLR blade shutters achieve, what, an order of magnatude less shake? Even with 4X image area to shutter, I can't believe that Pentax engineers couldn't devise a better shutter system for the 67II given the modest spec. of the system (1/1000th top speed, 1/30th flash sync). Cost was doutbless an issue, but again, compared to 35mm SLR's, the price/performance ratio of the 67II shutter is nowhere near what smaller bodies achieve.

I recently inherited my Dad's venerable Nikon S2 rangefinder. At equal shutter speeds, with the 67II's mirror locked up, the S2's shutter "shake" is astonishing slight compared to the 67's. Yes, the 67's curtain shutter is four times the size of the S2, but the S2 is a forty year-old design! To me that indicates that, if Pentax wanted to stick with a curtain shutter for reasons of economy, they still could have designed a better-damped one.

I'm happy with the sharpness of my shots using my 67II handheld, but I don't have anything longer than the 165mm in my bag and compromise on film speed rather than shoot slower than 1/90th. I have noticed my tripod-shot negs have gotten appreciably sharper since I shelled out for the herkin' Gitzo 1410 and Arca-Swiss B1. But the price margin I paid for the monster legset and ballhead, over a more modest setup, would pay for half a new 67 lens. That's money out of Pentax's pocket. And though I'm drooling over the new 300mm (not because of the ED glass but for the much shorter min. focus), there's no way I'd lay down two kilobucks (and change) for one without being able to shoot with it on one tripod.

Steve, you've written a number of times that Pentax doesn't seem to respond to customer input. Seems to me what the 67 line needs more than anything is a savvy product marketing guru focused on the USA/Euro sales market, someone with the clout to get the Japanese home office to focus resources on the true priorities of the customer base.

-- Bill Baker (wab@well.com), May 11, 2000.

Bill, I can not completely agree with you points. Anyone starting in medium format photography should anticipate the costs of a high end tripod. Amateur photographers do not change into MF because they expect fast and cheap cameras but because they want to improve their image quality. For this goal a sturdy tripod is simply unavoidable and I have no problems when it costs as much as my 90mm lens.

To your S2 comparison: Accidentally, the old Nikon S2 is my only 35mm camera, so I know this little gem. If you compare the shutters of these two cameras it is immediately obvious that it must be MUCH more difficult to dampen the Pentax shutter. In addition, if you compare the slides of the 45 years old Nikon and the Pentax 67II you will confirm that the Pentax engineers have learned something during the last decades. The current optics are much better.

Having said this, I also wish that it would be possible to get pin sharp results without all the tripod/MLU hassle. But every camera system has its compromises and you have to find the system with the least disavantages for your own kind of photography.

-- Joachim Inkmann (Joachim.Inkmann@uni-konstanz.de), May 12, 2000.

If I remember well, a square shaped object inertia is heavily dependent upon its fisical dimension elevated at the second power. This is referred to an object rotating about an axis but actually I don't know what the shutter of the 67 case is. I can suppose it has a mixed movement linear-rotational. In any case the rotational inertia component could become 16 times greater if fisical dimension increase 4 times. That is maybe why it is not fair to compare 35mm shutters with huge 67 ones.

Just my 2 cents Roberto

-- Roberto Manderioli (ManderioliR@bfb.ima.it), May 15, 2000.