Architecture question

[lee_pengelly.]

I have a MPPMKV11 with 90mm lens, I have taken some shots of castles

and stately homes recently; set up with camera tilted up, back pulled

out so film plain was level, focus on building facade at F45.

When I got the trannies back I have soft focus on the tops of the

buildings and the immediate foreground.

I cannot use any rise with this camera/lens combination because the

lens is right back in the body. The back was levelled with spirit

level. Where am I going wrong ?, help!!!

Lee.

[david_goldfarb]

Film plane is level to the building and the camera is tilted up, so that the lens is effectively tilted back? That should put the focus plane on the diagonal running right through the building facade from back to front, so of course the top and the base will be out of focus. The point of focus at the base will be somewhere behind the facade, and up top it will be in front of the roof.

 

Do a search on the Scheimpflug rule to see what was going on.

 

In this situation, front rise is the easiest approach. If the camera doesn't allow it, directly or indirectly using front and rear tilt, then you need a different lens or a different camera, or you need to stand in a different place, and maybe crop.

[wayne_crider4]

In what relation was the lens plane to the film and back plane?

[brooks short]

Lee,

 

You adjusted the film plane for parallel vertical lines. You also need to adjust the lens plane, parallel to the building facade.

 

When you tilt the camera up, you must resquare the lens and film planes for a shot like this.

 

So what is a MPPMKV11 camera anyway? View, field, technical camera?

[Troll]

If you can't raise the camera lens, either 1) stop the aperture way, way down, or 2) just make the picture without moving anything, and correct the convergent verticals when enlarging (tilt the easel and stop the lens way, way down).

[terry_dvorak]

http://www.mppusers.freeuk.com/mppproducts.htm

[colin carron]

Lee,

 

I'm not quite clear from your description how the camera is configured but when using a 90/6.8 Angulon on my Mk 7 for building shots I always use it with the bed dropped, the back in its normal position and a flat panel. Because of the position of the lens on the back track I have to take care that this set-up is firm which means getting the standard and track in exactly the right positions. Tricky but possible IMO.

 

I find that with this configuration I can get about 20mm of rise with a flat panel and about 30+ mm of rise using an offset flat lensboard. I have made two special lensboards for my w/a lenses - one has a reversible offset panel - centred one way up and 15mm built-in rise the other way round. The other board has an inset rising panel similar to that found on older field type cameras. With these special panels the limiting factor becomes the lens image circle. If you are into DIY I can provide a drawing of the lens panels.

 

Something to bear in mind is that the Angulon has a soft outer part to the image circle. This is useable for skies but not for the tops of buildings. I am a bit baffled why you have the foreground out of focus. Are you having difficulty seeing the edge of the screen? A fresnel added to the ground glass would help there.

 

Colin

[bob_ashford1]

If you tilt the camera upwards you do not have any forward tilt of the lens panel on this model. Therefore you must use the camera on it's side (there is a second tripod socket for this) then you can use the lens boards swing to give you 'forward tilt'. If you don't know about the lens board swing press the tiny chrome tag at the base of the board upwards while swinging the board.

Colin, you built in rise boards sound interesting, please email me.

Bob.

[neil_koppes]

Also Lee, if you are not using a recessed lensboard-you should.

It will give you an extra inch or so of bellows draw to help in your

tilts.