Spangly
I wonder how many weeks are left? 3? 4? maybe more?
Spangly
I wonder how many weeks are left? 3? 4? maybe more?
No worries, Good things are worth waiting forOriginally Posted by Dean Jones
Episode 12 sees the making of the 'smalls'
Shown here are the fiddly bits... the rear panel that attaches to the Razzlok with the four stainless steel springs, cup washers and brass lockers needed to apply even and adjustable tension against the film holder. There's a cable release socket that will be attached to the left side of the camera just under the viewfinder window and a tripod adapter, should you need to attach the camera to a support. Next, the stainless covers that shield the front bed pivot assemblies and finally, the flash shoe adapter...where I slot the radio trigger. (I hate on camera flash).
As the previous auction number has now been replaced by item 290149081295, something should be stated regarding the seemingly urgent need for 'parallelism'.
As per second pic, observers may note that my Razzlok adapter actually sits on the camera's rail and as it is precisely machined parallel, it could not be influenced by adhesive or any other situation that would see it lack 'parallelism'.
I think the whole issue has been grossly over emphasized. Contrary to belief, 'Mr Caliper' can often tell lies,especially if not held perpendicular to the item being measured, or used by a novice untrained in engineering basics.
A far more accurate method of determining 'parallelism' would be to place the camera's film plane or adapter, face down on a polished granite surface table and with the placement of an accurately ground spacer inserted onto the camera body where the bellows attaches. The height could now be compared at various points, using a height gauge (pic 3).
Now providing the lensboard is perpendicular to the film plane and you happen to be standing in a vertical position, perpendicular to the ground with the subject situated exactly vertical and perpendicular to the ground that YOU are actually standing on, go ahead and shoot wide open.....you can guarantee absolutely, there will be no fall off in sharpness from top to bottom or side to side will occur.
Think about all this very carefully, next time you shoot hand held, wide open, without a tripod on anything but level ground.
Dean, that's great to see all the annoying fiddly bits are coming along well too
I'm away next week so I look forward to another episode (or two?) when I return from France!
There's something I've been wondering.
Since the film plane has to be moved away from the original film plane to achieve 4x5" coverage, how do you deal with the issue of lens placement?
The original rails and the rangefinder coupling arm mechanically restrict moving the lens carriage backwards to compensate for the film plane displacement. Also, I don't think there's enough room to move the lens board within the lens support/pivot mechanism and still retain the possibility of folding the camera.
This is giving me a headache. I'm sure there's a simple solution I can't think of.
It's quite simple! A longer focal length of 150mm allows moving the film plane aft, without upsetting anything else.
Cheers.
http://homepages.ihug.com.au/~razzle/index.html
Yes, well, I suppose that's a solution.It's quite simple! A longer focal length of 150mm allows moving the film plane aft, without upsetting anything else.
Cheers.
http://homepages.ihug.com.au/~razzle/index.html
But how on earth are you able to grind the microscopic cams to such precision? Do you have something like a cannibalized Polaroid turned into a grinder?
Simple answer Lasse.....I made myself a concentric cam grinding jig
A block of aluminium with a peg? You sure you're not pulling my leg here? How's it work?Simple answer Lasse.....I made myself a concentric cam grinding jig
Now that's a trade secret
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