making a barn door shade for 7 x 17

[phil sweeney]

Hi Dan,

I just picked up a set at Home Depot that will work if I do not find something better. Now I have to figure how to cut a 3" hole in the garolite.

[Dan Dozer]

Phil,

Not sure the best way if you don't have a hole saw. Garolite is somewhat prone to chipping on the back side if you don't have it securly against something like a wood block backing - I learned that when drilling 1/4" holes in it.

You might try a small grinding type of bit in a dremmel working around the outline of the circle and then use a dremmel sanding drum to smooth it out.

Dan

[phil sweeney]

Phil,
the dimension of the opening doesn't need to change when you change the bellows draw provided you use the same focal length lens. Only if you wanted to change the film format you would need to change the opening dimension too.

Hi GPS,

Not sure I follow you on this. I attached a drawing (originally from autocad). The magenta lines show the angle of view to be smaller at 17 inches draw versus 15 inches. I realize the difference is not that much. Is my illustration an incorrect?

phil

[GPS]

Phil,
I'm afraid you mix up concepts here (angle of coverage, angle of view, image circle etc.) The lens angle of view doesn't change with belows draw, even if the image circle does. To make it simple - you don't really need to change the shades dimension when focusing.

[phil sweeney]

GPS,

thanks for your reply

phil

[phil sweeney]

Here is my 250 grams barn door shade. I ended up using 1/32 inch garolite for the panels. I found I can use on my RB67 also. Notice the small front flaps that are needed for the longer lenses.

[GPS]

An interesting way of storing your knifes, Phil (picture # 4). How do they hold on that rack, handles down? Magnets?

[phil sweeney]

Hi GPS,

Yes its a magnet. Made more for a shop than a kitchen, but Little Mama does not mind.

[GPS]

Thanks for the clarification, now I know your knifes attract forks...
Just a small detail, Phil - I don't know if you use the shade for different lens diameters (on your RB, perhaps?) but if not (and only in such a case) you could use just one nylon screw attached to the appropriate ring. Less to screw, of course and even more stable on the lens rim.