Matte Box questions/observations at DVinfo.net

Nick Mavropoulos · June 17th, 2007, 02:02 PM

I will be looking into getting a MB in the near future and wanted to think out loud for a moment. If I'm mistaken in my thinking please let me know.

It's my understanding that a MB out to be as deep as possible without introducing any vignetting. Having said that, a MB that is optimally deep enough for, say, a 85mm lens ought to vignette when used, in the same configuration, on a 50mm lens. If you throw in the fact that some lenses project their image on a 4:3 CCD while others (HVX) use a 16:9 CCD, a MB optimally configured for one lens on a 4:3 cam (e.g. DVX) ought to show vignetting when put on a 16:9 cam (HVX) even at the same focal length.

Which brings me to my next thought.

Are the MB's that dvxuser's generally purchase manufactured to spec's that make them work optimally with a specific cam? Actually, the question REALLY should be if the MB is made to work best for a given focal length coupled with a specific imager size? If this is so, and I suspect it may be, it appears logical to me that the manufacturer would build their MB to work best at the widest setting (smallest focal length) of a given cam in order to minimize the possibility of vignetting. This, of course, is a compromise because the optimal MB setup for a specific cam at 10mm may not be the optimal MB setup for the same cam at 80mm. In the latter case, the MB should be deeper. I suspect this very issue is part of what the additional flaps on a non-bellows MB are meant to address.

Are non-bellows MB's (such as the Chrosziel and its ilk) designed to work optimally with a specific camera, at that cameras widest setting?

Are the MB flaps intended to further optimize what may be a far from optimal default MB configuration?

I think its worth asking these questions before plunking down the potentially sizable cash for a MB.

Thanks all,
Nick

Rohan Dadswell · June 17th, 2007, 06:36 PM

Nick you are spot on.

In the old days on 35mm cameras the matte was placed on the outside of the box and changed whenever you changed your lens. So you had a set of lenses and a matching set of mattes. Zoom lenes and fast video shooting has changed all that.

If you are not going to want to use filters you are probably better off sticking with the lens hood that came with the camera and saving your money as it will block the same amount of light as a solid MB. MBs make the camera look good and more 'professional' but if they don't block the light hitting the lens then they are a waste of space.
Side wings and top flag work so long as you use them properly - a lot of people just set them to the widest shot and then leave them.

I like MB with bellows (Chrosziel makes some good but pricey ones) as you can quickly side the matte in & out to suit the shot.

Nate Weaver · June 17th, 2007, 08:33 PM

Quote:

Originally Posted by Rohan Dadswell

In the old days on 35mm cameras the matte was placed on the outside of the box and changed whenever you changed your lens.

This is still the case in the 35mm world when you shoot with primes and the right mattebox.

You can specify that they include the "hard mattes" with the matte box kit. It's not uncommon.

Jim Andrada · June 18th, 2007, 08:27 AM

And a further wrinkle for those old guys (like me) still using large format cameras is that you almost always use a bellows which not only changes length, but has a front that can shift up and down and sideways to follow the vertical and lateral shifts of the front lens itself.

Probably not an issue with video :<)

June 17th, 2007, 02:02 PM	#1
Nick Mavropoulos New Boot Join Date: Jun 2007 Location: Raleigh, NC Posts: 6	Matte Box questions/observations I will be looking into getting a MB in the near future and wanted to think out loud for a moment. If I'm mistaken in my thinking please let me know. It's my understanding that a MB out to be as deep as possible without introducing any vignetting. Having said that, a MB that is optimally deep enough for, say, a 85mm lens ought to vignette when used, in the same configuration, on a 50mm lens. If you throw in the fact that some lenses project their image on a 4:3 CCD while others (HVX) use a 16:9 CCD, a MB optimally configured for one lens on a 4:3 cam (e.g. DVX) ought to show vignetting when put on a 16:9 cam (HVX) even at the same focal length. Which brings me to my next thought. Are the MB's that dvxuser's generally purchase manufactured to spec's that make them work optimally with a specific cam? Actually, the question REALLY should be if the MB is made to work best for a given focal length coupled with a specific imager size? If this is so, and I suspect it may be, it appears logical to me that the manufacturer would build their MB to work best at the widest setting (smallest focal length) of a given cam in order to minimize the possibility of vignetting. This, of course, is a compromise because the optimal MB setup for a specific cam at 10mm may not be the optimal MB setup for the same cam at 80mm. In the latter case, the MB should be deeper. I suspect this very issue is part of what the additional flaps on a non-bellows MB are meant to address. Are non-bellows MB's (such as the Chrosziel and its ilk) designed to work optimally with a specific camera, at that cameras widest setting? Are the MB flaps intended to further optimize what may be a far from optimal default MB configuration? I think its worth asking these questions before plunking down the potentially sizable cash for a MB. Thanks all, Nick

June 17th, 2007, 06:36 PM	#2
Rohan Dadswell Major Player Join Date: Jun 2006 Location: Canberra Australia Posts: 228	Nick you are spot on. In the old days on 35mm cameras the matte was placed on the outside of the box and changed whenever you changed your lens. So you had a set of lenses and a matching set of mattes. Zoom lenes and fast video shooting has changed all that. If you are not going to want to use filters you are probably better off sticking with the lens hood that came with the camera and saving your money as it will block the same amount of light as a solid MB. MBs make the camera look good and more 'professional' but if they don't block the light hitting the lens then they are a waste of space. Side wings and top flag work so long as you use them properly - a lot of people just set them to the widest shot and then leave them. I like MB with bellows (Chrosziel makes some good but pricey ones) as you can quickly side the matte in & out to suit the shot.

June 18th, 2007, 08:27 AM	#4
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	And a further wrinkle for those old guys (like me) still using large format cameras is that you almost always use a bellows which not only changes length, but has a front that can shift up and down and sideways to follow the vertical and lateral shifts of the front lens itself. Probably not an issue with video :<)