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06-02-2009, 04:42 PM   #16
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QuoteOriginally posted by Quicksand Quote
Grooves or dimples. An old Ricoh lens I have uses dimples that could probably be reproduced with the tip of a drill bit, while those grooves could probably be hacksawed. (Carefully!) I'm not sure which the Cosina uses.

As you can probably tell, I've been thinking about taking apart the mount end of my Cosina and adding the half-stops myself, but I'm wary of not putting it back together successfully. That's a common problem I have once I take things apart.
Set up a video camera and set the pieces aside in separate sections of a tray, in order (and tell the camera what you're doing the whole time).

And then let me know how hard it is to do the whole thing, since I'd be interested in replicating this if I manage to snag one in the future =)

06-02-2009, 05:51 PM   #17
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I've found that getting the aperture ring off a MF prime isn't actually a major operation. You usually only have to screw off the back plate and you can leave the aperture lever in place so you're not actually messing with the insides of the lens.

Once you've got it off you should be able to dremel out a couple more grooves.

I think i'll still get an A lens.
06-02-2009, 08:38 PM   #18
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QuoteOriginally posted by ILoveVerdi Quote
Set up a video camera and set the pieces aside in separate sections of a tray, in order (and tell the camera what you're doing the whole time).

And then let me know how hard it is to do the whole thing, since I'd be interested in replicating this if I manage to snag one in the future =)
It's not that hard. Four screws for the mount. Disconnect a spring and lift off the part containing the aperture lever. Then lift off the aperture ring. Unlike the Pentax arrangement, this lens has the slots cut in the top of the rim of the aperture ring, not the inner side. The ring is then trapped between the mount and the lens barrel. The bearing isn't under pressure once you remove the mount so it won't spring off into space like on a Pentax lens.

Making new slots seems feasible. How depends on the tools you have. I just put it back together; too many other lenses apart right now.
06-03-2009, 06:27 AM   #19
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QuoteOriginally posted by ILoveVerdi Quote
stopping down on a 1.2 lens?! for shame.

When I eventually procure one of these I plan on setting it to 1.2, leaving it there, and getting drunk off the bokeh.
Since I got my K50 f1.2 I haven't use my FA50 anymore.. so I did stop down when I use my 50/1.2
I remember it has half stop on my K 50/1.2. I would recommend the A 50/1.2 as it has 9 blades as K50/1.2 has 8, If you have the cash

K 50 f1.2



Last edited by vizjerei; 06-03-2009 at 01:11 PM.
06-03-2009, 09:04 AM   #20
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be careful mate, you can get pretty wasted on the bokeh this lens can produce..


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