Kuzano
15-Jan-2012, 18:38
OK... I've made my opinions clear on hand holding 4X5. However, the obsessive trend for retaining a range finder on certain conversions to large format makes me somewhat interested in exploring the retention of the range finder on the Pathfinder 110, 110A, 110B and 120 cameras, along with the use of the rangefinder from the 900 cameras. I have samples of each of these.
However, I am not prepared to spend a lot of time on the rangefinder aspect.
So, I've made some observations and some speculations and would like responses from the forum.
Observations:
1) first the rangefinder on the Pathfinders is calibrated to 127 Ysarex/Pola lens/shutter arrangement, or the Yashinon lens used on the 120.
2) the film plane is fixed, and the front standard (with no movements) is movable and linked to the rangefinder
3) Changing the lens to 150mm would increase the distance from lens to film plane by .9 inches, or 23mm
4) Changing the lens to a 180mm would increase the distance from lens to film plane by 2.0 inches or 53mm.
5) using the 127mm lens would require the film plane opening to be set back enough to increase the coverage to from 3X4 inch pack film to 4X5 film size.
6) The opening would have to move back about 1 inch to cover 4X5, using the angles from the lens opening to the sides of the desired 4X5 film (both directions)
7) to continue to use the 127 lens, the lens standard would have to be move, along with it's range of movement, back on the door by the same amount.
I am working this evening on a mockup on my extreme cut down pathfinder, to confirm the setback distance to cover the 4x5 film frame.
Premises:
1) If I move the film plane back and correspondingly move the front standard back to retain use of the 127 Ysarex/Yashinon, the range finder will not need modification? Is this correct?
2) If I move the film plane back enough to set the film plane for 150mm, or far enough back to use a 180, BUT ALSO continue to use the same front standard placement on the Pathfinder door, IS IT POSSIBLE that the rangefinder will work without modifying the cam or other major work? In other words, can the rangefinder focus properly for those longer focal lengths, if the lens maintains the same position as original?
I am working right now on my original idea of cutting the Pathfinder down extremely, and ditching the rangefinder. Once I have the film plane placed I will go to work on a back system.
One back system will use a very simple mechanism. First a friction slot that will use Double Dark slides. Then I will convert a DDS to be a simple Ground Glass holder, and then use DDS film holders.
Second, since I have a couple of hundred envelopes of Quick and Readyload singles, I will use the same converted DDS holder to Ground Glass and friction slots, or perhaps a Graflok style system for the slots in my Quickload holder.
Then I can go on to other systems, although a workable Graflok style back should cover almost every other consideration.
However, if I am going to have to consider regrinding cams, I will undoubtedly ditch the rangefinder mechanism altogether and keep the system simple and usable. The other option would be to just go with infinity focus and create a fixing system on the front door/standard that locks in for 127 and 150 infinity focus, if GG is too complex for some people to manage:confused:
I should add here that my goal here is to create a kit style conversion that slips over the considerably cut down Pathfinder body and could be user installed. The simplest of these would be using the 127mm, but the change of lens from 127 to 150 is really rather straight forward. Again the goal is a very simple slide on conversion that one could do themselves to a complete Pathfinder, foregoing the rangefinder.
However, I am not prepared to spend a lot of time on the rangefinder aspect.
So, I've made some observations and some speculations and would like responses from the forum.
Observations:
1) first the rangefinder on the Pathfinders is calibrated to 127 Ysarex/Pola lens/shutter arrangement, or the Yashinon lens used on the 120.
2) the film plane is fixed, and the front standard (with no movements) is movable and linked to the rangefinder
3) Changing the lens to 150mm would increase the distance from lens to film plane by .9 inches, or 23mm
4) Changing the lens to a 180mm would increase the distance from lens to film plane by 2.0 inches or 53mm.
5) using the 127mm lens would require the film plane opening to be set back enough to increase the coverage to from 3X4 inch pack film to 4X5 film size.
6) The opening would have to move back about 1 inch to cover 4X5, using the angles from the lens opening to the sides of the desired 4X5 film (both directions)
7) to continue to use the 127 lens, the lens standard would have to be move, along with it's range of movement, back on the door by the same amount.
I am working this evening on a mockup on my extreme cut down pathfinder, to confirm the setback distance to cover the 4x5 film frame.
Premises:
1) If I move the film plane back and correspondingly move the front standard back to retain use of the 127 Ysarex/Yashinon, the range finder will not need modification? Is this correct?
2) If I move the film plane back enough to set the film plane for 150mm, or far enough back to use a 180, BUT ALSO continue to use the same front standard placement on the Pathfinder door, IS IT POSSIBLE that the rangefinder will work without modifying the cam or other major work? In other words, can the rangefinder focus properly for those longer focal lengths, if the lens maintains the same position as original?
I am working right now on my original idea of cutting the Pathfinder down extremely, and ditching the rangefinder. Once I have the film plane placed I will go to work on a back system.
One back system will use a very simple mechanism. First a friction slot that will use Double Dark slides. Then I will convert a DDS to be a simple Ground Glass holder, and then use DDS film holders.
Second, since I have a couple of hundred envelopes of Quick and Readyload singles, I will use the same converted DDS holder to Ground Glass and friction slots, or perhaps a Graflok style system for the slots in my Quickload holder.
Then I can go on to other systems, although a workable Graflok style back should cover almost every other consideration.
However, if I am going to have to consider regrinding cams, I will undoubtedly ditch the rangefinder mechanism altogether and keep the system simple and usable. The other option would be to just go with infinity focus and create a fixing system on the front door/standard that locks in for 127 and 150 infinity focus, if GG is too complex for some people to manage:confused:
I should add here that my goal here is to create a kit style conversion that slips over the considerably cut down Pathfinder body and could be user installed. The simplest of these would be using the 127mm, but the change of lens from 127 to 150 is really rather straight forward. Again the goal is a very simple slide on conversion that one could do themselves to a complete Pathfinder, foregoing the rangefinder.