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Lens & Rangefinder calibration and Coupling

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

Welp, here is where I try and explain the best as to lens compatibility and why I chose to go with a 150mm as the primary lens. Also I’ll try to touch base on future hopes to render this problem null and void as well as some of the issues surrounding multiple lens use, what I’ve done so far to make it possible to use more than one lens and some of problems reaching this point as well. I’m always open to any suggestions you might have and if there is anything you see that I either forgot to mention or info you would like more detail on please let me know so I can update the page. I want to provide as much info as possible not only to inform about this project, but to help explain lens issues for other conversion lens coupling as well. (Some photo’s made possible by other creators)

Lens length Compatibility: - 80mm to 150mm(possibly shorter but I have nothing to test with, I suspect the rail guide for the release to close will obstruct beyond the 80mm mark)

 

Rangefinder Compatibility: 150mm (reasoning is explained below, but - special request can be made upon ordering)

 

Lens obstruction (bellow and front standard): - 57.60mm lens mount clearance to front standard, bellows is approximately the same due to space requirements of the side standard rails from movements. This may change in future designs, see “Updates” and Newsletters for more info.

 

Bellows Movement Lens obstruction with “Super and ultra – Wide” lenses and/or wide-open f/stop lenses are for the most part non-obstructed except in extreme movements while in tilt or full swing.

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

Photo's/ Drawings curtesy of "Byron" creator -

salihonba J

Now for the Cam coupling to the rangefinder focusing, I’ve set the primary lens (150mm) to accommodate for the furthest lens for two reasons. First being the full extension of the rail and bellows reach. As you will read below there are certain obstructions to placing the infinity stop and while I may have created a way around this, the design it’s self is not up to my standard of retail. I’m working out as many solutions as possible but due to the entire design there are leaps that need to be made or I’ll begin production on a second front standard rail design (which very well be the end plan altogether anyways). If so the idea behind why I’ve stuck it out with 150mm as the primary lens will change allowing for the option to be wide open. These changes will be posted in the newsletters and in the updates page as well.

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

This is the original 127mm lens Cam, the 900's Cam (135mm) is almost identical in curvature and size.

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

Another tough obstacle to cross was centering the lens position and finding room for all the Swing, Shift, Rise, Fall and Tilt arms and release levers while staying in the boundaries and confines of the original body in order to properly close as well as function as intended. No easy task that required a lot of trial and “do overs”.  This is also one more place were the lens length plays into the picture about the 150mm as primary.  In order to allow for a 150mm, 135mm, 127mm, down to the 90mm or 80mm the entire movements system would have to change to account for the lens compartment door to avoid an obstructed view if per say one choose to mount a 90mm Super-Wide as their primary lens, giving need for the lens position to rise and for me to have multiple designs for each lens mounted as a primary. Sorry but that far too much machining and stock to keep on hand. Also as shown in the picture below the original bellows dimensions will no longer work, so after some pain shaken time with an overseas designer/builder and I feel I’ve finally come up with a solid workable design for replacement(at least for now, see “Custom Options” page for custom colors) with full ability to give you un-obstructed view to the entire 4x5 film plane as well as a companioning full lens movements, able to fit in the tiny space allowed for closing the front and staying as close to as possible of allowing for Wide lens cells not to add restriction and wear on the bellows why using more extreme moments…Whew!(that was one hell of a task as well).

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

This part proved to be one of the more difficult puzzles to solve.

How to allow for multiple lenses while also allotting for a primary lens coupled to the Rangefinder.

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

The main issue solving the infinity clip to function with multiple lenses is the way the rail and front standard carrier were originally designed, as you can see in the photo to the left the arrow points to the trouble maker. Genius design, but the design only allows for a primary lens to move in the slotted space given. So this too had to be re-thought I’m still working out a completely trouble free system but that is by far the harder of all the modifications made to the EVO. I do have a design in my head, but have as of yet to run into anybody that might be able to help me build what’s stuck in my noggin. Soon, I hope this will too come to pass and we will have overcome this obstacle. More info will become available as the infinity clip progresses and all issues resolved. I’ll also post these updates as they happen in the Newsletter section as well so please sign up if you’re interested or have bought an EVO. I’m confident this will not take much longer to solve and make as easily useable as possible. As always I’m open to any suggestions you may have.

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

More info will become available as the infinity clip progresses and all issues resolved. I’ll also post these updates as they happen in the Newsletter section as well so please sign up if you’re interested or have bought an EVO.  

SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5
SecondShot Cameras| Polaroid Conversions| Oregon, Polaroid Evo 900 4x5

In addition, the bellows obstructions and lens limitations are questionable as I have no ultra-wide lenses to check with other then measuring for estimated circumference from internet specifications. Most seem possible but I’m unclear about such lenses as the 150mm 2.8 rear lens cell as that too I’ve been unable to look at and measure but I’m confident there is enough room to accommodate for such rear lens cells without damaging the bellows while in extreme movement situations. But possibly over time they could wear down. Bellows will be easily replaceable just for this reason along with color changes if so desired.

 

 

More info as it becomes available.

 UPDATE - 1/24/15

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