making a barn door shade for 7 x 17

[Robert A. Zeichner]

Phil,

I think you are on the right track. I like the idea of the extra panels. I would urge you to consider all four sides being shaded as there are often highly reflective objects below the lens (snow, sand, etc.). You might also consider making one pair of leaves narrower at the front than at the rear end, shaped like a rhombus. This way, if you are using lenses with huge coverage or using lots of movement, you will be able to fold them inward without getting in the way of each other.

[Dan Dozer]

Hi Dan,

Thanks for the photos. How did you cut the slots for the fins?

Do you think the 1/32" garolite would be too thin?

phil

The slots were cut with a 1/16" slot cutting router bit. I had both the bit and the garolite left over from building my 8 x 20 film holders. I'm not sure if you can get a slot cutting router bit that is thinner than that. I don't think that going with 1/32" garolite will be of any advantage. The 1/16" seems to work just fine. If you don't have a router, another option could be to sandwich together three thin strips of material with the center strip the same thickness as the fin. Note that I haven't found any type of glue that works with Garolite - I'm sure there is some, but I haven't found it yet.

One bit of advice - the aluminum channel does not like to be bent any more times than once. I cut/filed a 90 degree "v" in the flanges of the channel where the corners are and bent the channel at the web. However, since Aluminum is soft, if you try to rebend the web part, it will likely break in two. You will need to practice to get the V the right size.

If you don't have any garolite and want to try this method, send me a note with your mailing address and I can send you a couple of pieces. I have a little left over that I'll probably never use.

Dan

[phil sweeney]

Phil,

I think you are on the right track. I like the idea of the extra panels. I would urge you to consider all four sides being shaded as there are often highly reflective objects below the lens (snow, sand, etc.). You might also consider making one pair of leaves narrower at the front than at the rear end, shaped like a rhombus. This way, if you are using lenses with huge coverage or using lots of movement, you will be able to fold them inward without getting in the way of each other.

HI Robert,

Thanks for chiming in. I have read your article. I use series IX lens shades and have always know they are a compromise device. I do intent to have a 4 sided device. I am going to try some plastic piano hinge. If that does not work (loose hinge) I'll have to make something with a tighter operating hinge or utilize the dreaded velcro for starters. The article in View Camera: "Camera Flare" described problems I have had quite often.

Can you make any comment on the fourth image where I have illustrated what I believe will be needed when using significant front rise?

thanks

phil

[phil sweeney]

Hi Dan,

I'll probably use an epoxy. If it works on ABS plastic I hope it will work on the garolite (roughed up with sandpaper). I am going to try to epoxy the garolite to the hinge.

Phil

[Robert A. Zeichner]

HI Robert,
Can you make any comment on the fourth image where I have illustrated what I believe will be needed when using significant front rise?

thanks

phil

Phil,

The thing that comes to mind is that you might want to put a slight bend in the doors where they meet the hinge, sort of like the wings of a WWII Corsair fighter. This way there will be clearance enough near the hinge to allow maximum adjustment. I've attached a photo for reference. I think the bend should be where the flocked paper I rubber cemented to the aluminum ends. I hope that is of some help.

[phil sweeney]

Here are some photos of my prototype. The images show the camera with 17" bellows draw. I was focused indoors and camera set with max rise of 3 inches. I was pleased to see the final position of the top and bottom flap resemble what I illustrated in my drawing. At 15" I think the side flaps as adjusted will just encroach on the image.

[GPS]

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.

[phil sweeney]

I am looking for some very small aluminum or plastic positioning hinges. I am getting a couple samples from ABC plastics but have yet to find anything similiar elsewhere. I would prefer to find something about 1/2" wide and about 1" across entire hinge open. I'd appreciate any advice on sources!

[Robert A. Zeichner]

I am looking for some very small aluminum or plastic positioning hinges. I am getting a couple samples from ABC plastics but have yet to find anything similiar elsewhere. I would prefer to find something about 1/2" wide and about 1" across entire hinge open. I'd appreciate any advice on sources!

The model aircraft guys might have the answer you are looking for. Check out
http://www.hobbypeople.net/gallery/566562.asp

[Dan Dozer]

Hi Phil,

Have you checked your local home center? If brass is OK - I found some brass hinges just about the size you mention at Lowes in the cabinet section.