MOD: click-stop aperture – 7artisans 35mm F1.2 lens---by Iurii Zvonar

7artisans35mm F1.2 lens has click-less smooth rotating aperture ring by design. Its texture is very different from

focus ring so it’s easy to identify by justtouching rings while keep looking into viewfinder.  However when  you

want to check the aperture value  during shooting,  you have to look at the top of the lens to  read it,  and make

sure desired value is set.  Alternatively I’m simply rotating aperture ring to the very end to set F1.2.  Today  I’ve

finally modded this lens to the aperture click-stop version.

Initially  my point was to  avoid any direct lens modificaitons like drilling or cutting.  I’ve tried few  different  

designs for click-stop mechanics,  but all of the mfailed  in  a short time,  or didn’t  provide enough feedback.

Then  I decided to implement one of most simple  and  reliable solution:  spring loaded ball. This design is used

by many lens brands, including Fujinon XF model line. I like the idea of having noticable loud clicks on aperture

stops.  The aperture ring also securely holds the position once metal ball is catching the slot.

So the first step is to find good place for about 3-3.5mm deep hole under theaperture ring.   I’ve drilled  it  very

carefully to not drill it through, and used2.4mm drill in super slow mode. Secondly I’ve marked hole positionon

aperture ring for different values using pencil, and later hand drilled single tiny spot marked for F1.2 setting.  On

the picturebelow you can see all slots,  but I had recommend to start with one first to make sure the ball location

perfectly fits the stop position.

I’ve found small 1.9mm metal ball, and also cut 3.5 turns of metal spring from regular lighter (used to

push the flint up). I’ve jently  curved the spring endsto make them more flat.

Then I’ve put the spring to the lens hole, and gently located the ball on top, soonly half of the ball is visible.

I’ve applied aperture ring and rotated it fewdozen times to make a line on the inner side of the aperture ring.

Later  I’ve used the line formed by the ball to perfectly center the aperture stop slots and make them wider up to

1.6-1.8mm.  I’ve intentionally made F5.6 and F8 slots smaller, so stop-clicks are less intensive there. As a result I

have audible clicks wile rotating the aperture ring. It feels like the Voigtlander aperture, with only difference that

I didn’t add half-stoppoints. Also aperture value remains the same until I decide to change it, no more accidental

rotation of aperture ring. Later I've decided to add visible red dot on the silver mount ring of 7artisans 35mm F1.2.

It’s much more visible now which F value  is set.