Matte Box

[Noah Posnick]

I want to build a bellows style matte box/ sunshade for my GL1, but I have no idea where to start. I don't necessarily need it for functional reasons, mainly I just want it to look great so that it gives this small camera a more professional look for when i go to shoot my film. I feel that if people see this cool thing on the front of my camera it will seem like a bigger budget and more professional productions. I would like to build this out of metal maybe so it looks cool. Also I'd like to build a rail mount system for it if possible.

[Graham Bernard]

This any good Noah?

http://homebuiltstabilizers.com/


Grazie

[Noah Posnick]

There are some really nice homemade matte boxes and rail systems there. That's the type of thing I'd want to build. But my problem is I still have no idea how to build it.

[Charles King]

Noah. Go to the 'tips' section on the HBS site. There is at least one drawing on the site for a matte box.

[Noah Posnick]

I checked that, but to be honest I think just the pictures are even more explicit than those drawings. I'm not the most innovative guy when it comes to making equipment like this so the more detail I can get the better.

[Charles Papert]

Noah,

If you are going to all the bother of building a mattebox for cosmetic reasons, you might as well make it functional on some level while you are at it.

A mattebox has two purposes (not counting that it makes the camera "look professional"): to protect the lens from stray light and to house filters and mattes.

Building filter trays or mounts may be more complicated than you want to get into, but at the very least I would recommend an eyebrow (top shade) as part of your design. This will allow you to shoot into backlit sun much more effectively without flaring. A spring or tension mounted system like the barn door on a lighting instrument is ideal, you want to be able to adjust the eyebrow easily and have it stay put.

As far as the rods are concerned, be aware that there is a standardized distance between 15mm rods (aka "minirods") that are used for cine and digital cameras alike (sorry, I don't have the spec). If you were to conform to this standard, you would be able to use other accessories down the road such as a follow focus. The height from the rods to the center of the lens is also standardized; this would allow you to use a production mattebox with your rods later on.

All this may be too complex for what you are planning, but I thought might be helpful to at least bring it up if you are going to all that bother.

[Noah Posnick]

None of that is too complex. And I completly agree that if I am going to make it "look pretty" I might as well make it functional. The only thing is I'd like to know much more specifics. For example what materials to use. Or how I can make it so that the sunshade stays in the place i want it to. Also like how long/thick should the rods be, how do I connect them to tripod mount, etc.

[Charles Papert]

Excellent Noah!

The only spec that I have at my fingertips is the diameter of the rods, which is 15mm. Carbon fiber will be your best lightweight bet, steel will be at the other end of the spectrum weight-wise. The length will best be determined by measuring your current setup with the GL2. Do you use a wide-angle, telephoto or anamorphic lens...if so, allow enough adjustability with and without the lenses). A base that allows the rods to telescope in and out makes this easy, rather than rods that are fixed to the base.

Also it is important to make sure that with a wide angle lens, your mattebox is big enough not to vignette under all conditions. It's best to test it throughout the focus and aperture range of the lens; at a particular setting the edge of the mattebox may become visible.

[Noah Posnick]

Thanks. I didn't even think about vignetting. How could I make the rails telescopic?

[Charles Papert]

here's one approach:

Take a solid rectangular chunk of Delrin or aluminum. Drill a hole in the center to acommodate the mounting screw for the camera and also include the small locating pin to keep the unit from spinning. Tap at least one 1/4-20 hole into the bottom surface as well as a locating pin hole. Now you can mount the block under the camera, and the whole thing can then mount on your tripod.

Then drill channels for each of the rods from front to back. A simple screw from the side can be used to fix the rods in place, but it is better to slit the sides slightly so that the screw is actually tightening a section of the channel around the rod, creating greater friction to lock the rods in place. Either way, you can now telescope the rods as you please.

I'm sure there are pictures of this sort of thing around, but I apologize that I don't have any to point you to.

I don't know if you are in Manhattan or NY State, but if the former is true you can stop by a rental house and take a look at a variety of baseplates and matteboxes to get some ideas.

[Noah Posnick]

Yeah, I'm in manhattan. Thanks a lot on those ideas. Going by a rental house is terrific. I never would have thought of that myself. How about the actual matte box though. I'd love a description of how to build it like you've just described how to do the support rails.

[Charles Papert]

Noah,

The subject of rails is fresh in my mind as I am currently having a machinist build me a base for my XL1 that incorporates these ideas plus allows for some other unique capabilities. However, I already own a Chrosziel 4x5 mattebox so I haven't had to go through the process of building one, probably someone else would be of more help on that. Good luck though!

p.s. regarding the rental houses--I used to work in NYC before moving to LA, but I'm not sure who would be the best to visit for this--possibly TCS, or maybe CSC. If you go up to a camera assistant doing a checkout and introduce yourself in a really respectful/polite manner and ask if you can observe quietly, chances are they will be able to help you more than if you approached the people who work at the rental house if you tell them that you are looking to homebuild a copy of their gear.