More mechanical wooden silliness

[oddcoach]

you could use a web cam with face recognition so it would only let your dog in and not the neighbors cat

[shoeshine]

OK this is cool....

a 30" mechanical IRIS window on you tube.
http://www.youtube.com/watch?v=TuEqH...layer_embedded

after watching that, Michael, any chance you could get and post some accurate dimensions from those camera parts you have?

I need to finish this project first but then I definitely want to play with this other style of iris.

[mikeacg]

Chris,

I'm off to meet with a client on a new website in the morning but I will definitely get the parts drawn up sometime later on tomorrow (well, I guess it's already today!). I'll do them in Illustrator so we all have vectors to work with for our designs.

I like what is happening with this post. It will be interesting to see what everyone ends up with...

Mike

[chiloquinruss]

Chris - thanks for the post! That is a very clever and simple drive mechanisim. Russ

[shoeshine]

Michael Schnorr quite graciously broke out his micrometer and measured and drew up an old camera iris he had. As per his request I am posting the files for anyone interested.

http://www.schaie.com/shopbot/Michaels_Iris.zip

Thanks Mike!

[mikeacg]

Thank you, Chris, for starting this whole discussion! It's great to see everyone jumping in with ideas!

Mike

[shoeshine]

OK as famous as I am for starting something new before the last thing is finished...

I played around with Michael's drawings to make sure I wasn't missing a better design.

Here is a stab at a more traditional Camera IRIS.


50516.jpg


50517.jpg


50518.jpg

Clearly I underestimated the thinness needed for the metal leaves. I used a sheet of .020 brass I had to cut some 4" d. leaves.

I got 6 of 12 in place before it started to jam at the center leaving an approx. 3/8" hole when closed.

Michael, could you throw a mic on your parts again just for giggles and get a thickness of the leaves? and what is the total diameter of the rings?

Chris

[mikeacg]

Chris,

That is the same problem I ran into with my plexiglas shade model. They can get away with being so thin in a lens as they basically support each other and are encased between glass so they can't get damaged.

The diameter of the rings is 2.085 and the leaf is approx. .002 thick (hard to tell for sure - at that size the Mic needle is thicker than the part so I used the edge of the needle).

Mike

[navigator7]

Aren't the shutter pieces on a real camera frosted?
Errrrr...Orange peel?
Or ......Not mirror finished?
I believe this is a technique to reduce drag.
Chris...your brass may need to be blasted or roughed up?

[mikeacg]

Chuck,

In actual fact, a shutter leaf is smooth and matte finish but that finish is more a matter of reflection than friction. In order for the 12 pieces of metal to overlap and close for as small a hole as possible (the smallest hole being largest Fstop number of that lens, resulting in a slower shutter speed and more detail), they just need to be as thin as they can be and still function. Any surface texture would just make them thicker. Friction/drag has nothing to do with it...

Mike