Play with Lens

 So far I made quite few lenses to obtain soft-focus or wide-angle pinhole etc,

mostly by utilizing single lens. (still, some of them seemed to be an achromatic

compound lens)  Single lens has inherent aberrations which produces soft image.

Furthermore, I’ve experimented soft images with focus shift or even with camera

shake/vibration using aberration corrected normal lenses. Though, those approaches 

were hardly called technique but more like an opportunist seeking a good luck, since 

the success rate was rather low = lots of try and only few will show the good results. 

That’s because, when the focus ring was rotated while camera’s shutter was open,   

the resulting shake gives devastating effect than a soft nice blur.

= make smooth focus shift while camera was held steadily. = That’s what I need. 

Inside of the Canon G9 compact camera, I found pretty useful mechanism.  

(1) A motor moves the lens.  (2) Small stepping motor shifts a lens for focus.

—– though, those two mechanisms were constructed on the same plastic piece.

(Photo above, left) = I needed to cut and separate its center mechanism out of the

lim with DC motor.  (second photo shows the separated piece = the lim which can

drive a cogged barrel — in the second photo top, the lens was placed in the barrel)  

Photo 3rd and 4th showed the center mechanism — the lens was pushed out most

and pulled inward most by its stepping motor.

The photo above, left is the cogged barrel = when it was rotated by the motor,

the barrel, hence the lens will be extended(= Pushed out) (photo center)  

When motor rotate opposite direction = lens was pulled in. (photo right)

Those function is exactly what I need for a smooth Focus-shift.

 In order to have an experiment to get a soft focus by the focus-shift ( by a normal

lens, not by the aberration) I took the lens unit out of a Canon 50mm FD lens.  

(Photographic equivalent of gouging the eye !)

( a disc shaped mechanism on the right is the Iris — very useful device )

The lens unit which I’ve put inside of the plastic barrel, in the photo before was this

Canon 50mm F1.8 Lens.  —– though, on the test, I found that this Canon 50mm FD

lens can’t give an infinity focus on Canon EOS = only usable closer than few meters.

(otherwise, the EOS’s mirror will hit the lens bottom.  😦  )

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Then, give a thought, what all those hustle for ?

—– Why not just modify a Canon EF 50mm for EOS = 

put an extra electronic connection to override their AF motor !

(Ideally, huck into the Canon camera’s OS and reprogram it to give a focus-shift while

shutter is open = was the best though, not only the risk to destroy the camera but also,

the Canon doesn’t like it at all. ) 

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