Mamiya 7 43mm lense problem with auxiliary viewfinder?

[sserata]

I have the 43mm lense for the Mamiya 7II. It's a great lens except for a persistent problem I have had for several years. It is pretty consistent so I know it's not a one-time fluke. I think maybe the auxiliary viewfinder that slides into the hotshoe is slightly off (for those who don't know, the 43mm on the Mamiya 7 is so wide that the internal viewfinder in the camera cannot accomodate it so you have to use this additional viewfinder which is a pain) By "off" I mean I suspect it is slightly off-axis, so that when you line up the shot thru it, it causes you to skew or swing the camera slightly. I am NOT talking about the parallax error. I shoot some architecture with this lense. I need the extremely wide angle, but because it is so wide it is extremely sensitive to the film plane not being perfectly parallel with the front of the building or structure. The viewfinder has a tiny bubble level in it (and I double check that with a larger level I put on the camera) so I am not talking about tilt, I know the camera is level front to back and it is level side to side. (Ok, technically I know the camera can't do tilts or swings or shifts because it isn't a view camera but you know what I mean)

It wouldn't matter if I was shooting landscapes or something, but in architecture the front of the building/structure has to be square on the film. I know, I know, you're saying, shoot with a view camera! Yes, I also use a 4x5, but for this project I cannot use a 4x5. What I see on the film is tilted/wonky horizons, and often the film looks as though the camera was slightly "swung" (film plane not parallel with front of building in the horizontal axis) Wish I could make a drawing. My question? Anyone else out there with the same lens/camera who has experienced the same problem? I have run 100's of rolls of film thru the camera and the problem shows up no matter how careful I am line to up the shot. I don't have the same problem with my 4x5 or my Pentax 67 or my Canon 5D, so I don't think there's something wrong with my brain!

Help!!
Thanks,
Scott

[DanielStone]

have you thought of using just a standard 3 way hotshoe mounted level? I don't have a Mamiya 7, but I have shot architecture with an RZ67, and I had no problems when using a 3 way level in the camera's hotshoe.

I'm not sure if you can fire the lens' shutter when the back is open, therefore being able to afford you the use of a ground glass on the film rails.

you might also want to try asking this same question over at www.apug.org

its for all analog users (I'm there as well). More users of the Mam 7 there than here. You should hopefully get the answer you need there.



-Dan

[sserata]

Dan, thanks for your reply. Yes, have tried various bubble levels including the 3way hotshoe mounted ones. I don't think this is a problem caused by the camera not being level. The camera is level. I think it is caused by the film plane not being parallel (in the horizontal axis) to the front of the structure/building. I think the film plane is slightly swung with respect to the building, causing the image on the film to look skewed horizontally, not vertically. It's as if I was shooting a 4x5 and had swung the back slightly. My only guess is that the viewfinder is off somehow and is causing me to not aim the camera accurately. Again, this is amplified greatly because the lens is so wide and I am close to the buildings.

I will take your suggestion and post this on apug.

Thanks,
Scott

[Rob C]

Dan, thanks for your reply. Yes, have tried various bubble levels including the 3way hotshoe mounted ones. I don't think this is a problem caused by the camera not being level. The camera is level. I think it is caused by the film plane not being parallel (in the horizontal axis) to the front of the structure/building. I think the film plane is slightly swung with respect to the building, causing the image on the film to look skewed horizontally, not vertically. It's as if I was shooting a 4x5 and had swung the back slightly. My only guess is that the viewfinder is off somehow and is causing me to not aim the camera accurately. Again, this is amplified greatly because the lens is so wide and I am close to the buildings.

I will take your suggestion and post this on apug.

Thanks,
Scott

I don't use the camera either, but is there any freedom of movement when you slide the viewfinder into the shoe? If there is, then you might try to put a tiny wedge into part of one side and see if you can thus correct for the effect or, at least, confirm in that way where the problem lies. With such a wide angle lens the smallest failure in the accuracy of the fittings would create noticeable visual errors, I would think, of a sort less manageable than simply poor rangefinder framing which you could solve by some small cropping later.

Rob C