Pentax 75mm Shift

[grant_lupton1]

Given the cost of the 75mm shift lens, how does it perform -

resolution across apertures, dealing with verticals, anything of

relevance?

 

Thanks in advance.

 

Regards,

 

Grant.

[eric friedemann]

I'm not a Pentax guy, but did shoot Mamiya RZs for years. Mamiya also has a 75mm shift lens.

 

 

As I shoot a fair number of buildings, a 75mm shift lens didn't make much sense to me, as it yields a 35mm format equiv. focal length of 36mm. This is too long a focal length for architecture.

[tom_musselman]

You will find lots of info about this and all P67 lenses in the Pentax 67 SLR forum. In my own test this lens is very sharp in the center wide open, but the edges are a little soft. The edges don't match the center, unshifted, until f/11. At f/22 the entire image circle is very sharp, meaning even shifted to 20mm the edge is very sharp. This lens stops down to f/32 with no image degradation. There is no noticeable barrel or pincushion distortion. Overall, this is my most-used lens for the P67. Good luck!

[grant_lupton1]

Dear Eric,

 

Thank you for the reply.

 

I see your point re focal length but I suspect (guess) that the current focal length(s) of shift lenses may be the limit(s) re optical design and/or performance (even cost).

 

As you will be aware, generally speaking, the wider the angle, the greater the distortion (converging verticals, pin-cushion). To eliminate this to an acceptable level may be possible in theory but prohibitive in practise.Of course, I stand to be corrected.

 

If any member could point me to examples using the Pentax lens, I would really appreciate it.

 

Regards,

 

Grant.

[eric friedemann]

Grant, you're right. Fuji has lenses that allow limited movements for its 6x8 SLR cameras, but the lenses are really large compared to RZ lenses in order to generate the larger image circles necessary. Also, the Fuji 6x8 cameras are physically larger. It is my understanding that 75mm is the shortest shift lens you could design for an RZ or a P67 without redesigning the camera bodies.

[grant_lupton1]

Dear Tom,

 

Thank you for the info. Now I just need to find one (used) for a reasonable price.

 

For your's and Eric�s interest, if you are not aware, www.zoerk.com may provide alternatives with their Shift adapter. As to their quality, I�m ignorant.

 

By the way, I always do a search re specifics, eg 75mm shift. Unfortunately, it�s pretty hopleless; citing question, then click on heading. Your then taken to countless questions undifferentiated.

 

Regards,

 

Grant.

[eric friedemann]

"(I)f you are not aware, www.zoerk.com may provide alternatives with their Shift adapter. As to their quality, I'm ignorant."

 

 

I'm aware, Zoerk's quality is outstanding and Zoerk's prices are high. Unfortunately, I think you'll find that Zoerk will not be able to provide a shifting lens- even a view camera lens- wider than 75mm for a P67.

[rod_sainty2]

Hi Grant,

 

You wrote: By the way, I always do a search re specifics, eg 75mm shift. Unfortunately, it�s pretty hopleless; citing question, then click on heading. Your then taken to countless questions undifferentiated.

 

Not so. I just clicked on "search", typed ""75mm shift"" and the system generated 18 specific responses to 75mm shift lenses.

[grant_lupton1]

Dear Rod,

 

I've just tried it (again) and it works perfectly (doesn't that always happen?). You've fixed it, haven't you?

 

Thanks, Rod.

 

Regards,

 

Grant