Maximum tilt on an MPP Mark 8 with a 90mm - Advice requested

[pauldc]

A question for anyone out there using MPP cameras in the field to shoot landscapes - any advice appreciated.

Just got some transparencies back which I took on my MPP Mark 8 with a 90mm Angulon (1968 vintage) lens. About the top 2 centimetres of the pictures were missing (it was black and cut across in a fairly straight line) and I am trying to work out why. The temainder of the picture including the bottom was all there.

It was an experimental shot to learn how to use forward tilt in a landscape setting. I used maximum tilt on the front standard of the MPP - must be about 11 degrees of tilt in all I estimate. Now I know this was too much tilt for what the photo needed but I was wanting to see the effect of maximum tilt. What I did was make the max tilt movement, lock the standard and then focus on the foreground interest in the scene. I was assuming that the tilt would then move some of the background in to focus. I stopped down to f22.

I dropped the front rail to the first of the 2 dropped settings to avoid getting this in the lenses view.

I know the angulon does not have much room for movements but I expected that if this were the problem then the edges of the image would go soft and maybe even show the edges of the image circle.

I used the MPP lens cone with the 90mm lens. I was using a standard bellows. Other pictures I took without tilt came out fine.

It looks to me as if something cut off the top of my picture - which I believe in the camera would be at the bottom of the bellows and ground glass as everything is reversed.

Do people have experience using wide (90mm) lenses and movements with the MPP?

 

[Ole]

I don't know the MPP, but it sounds like bellows interference to me. The 90mm Angulon will illuminate a full 5x7" film, albeit with soft corners.

 

[David H. Bebbington]

I don't have an MPP any more, but as you say the conventional wisdom with a 90 mm Angulon is to expect it to cover 4x5" at infinity at f16 or smaller with little or no movement. If you have an abrupt transition from sharp image to total cut-off, this could well indicate vignetting by the lens cone. Remember there is nothing magical about the lens cone, its only function is to allow the front standard to sit back further and be focused by rangefinder with the 90 mm lens. As far as I recall, when I had an MPP Mark VII, I used a 90 mm Angulon with a domed panel I made myself with about 12 mm extension - being a small lens, the Angulon sits in the usual domed panel like a tunnel and could easily vignette with too much tilt. As a rule, using back tilt is safer - it's quite easy to overlook vignetting on the focusing screen in the field.

 

[Richard Kelham]

If it is a straight line, albeit soft-edged, it does sound like bellows cut-off. Try setting up a similar shot and carefully examine the edges/corners of the ground glass with a loupe. It there is cut off it will be visible. Gradually ease back on the tilt until the whole screen is illuminated and then you will know just what the limits are.


Richard