Brevis workings?

[Marcus Marchesseault]

I am interested in the Brevis adapter but I want to know how it works a bit before ordering. How does the mechanism work? Is it a GG supported by posts like in the Letus? Is the current model the one with X and Y oscillation tuning? Can the adapter lock Nikon lenses into place? How is backfocus adjusted?

[Ken Willinger]

Check the following site for all the latest Brevis info:
http://www.cinevate.com/
You should find most of your answers there and can ask owners or Dennis on the forum.

[Marcus Marchesseault]

Unfortunately, I couldn't find how the Brevis works here or there and don't even know how to phrase the search. I figured that this forum or the one at cinevate would have people that know, but there haven't been any answers at cinevate since I posted Sunday morning. Even if I found an answer amongst older posts, the Brevis has been significantly changed at least once and some minor changes have been made along the way. I'm hoping to hear from a user that has purchased one fairly recently.

I know how the Letus works since I owned one. I know that the Redrock M2 has a spinning ground glass. I've seen pictures of Dan Diaconu's MPIC and it has an oscillating GG that seems to be supported in a sleeve or maybe perimeter bearing. I have not seen a picture of the inside of the Brevis and I want to know how the GG is supported and moved to get the grain-reduced image. I like to know how things work so I can get an idea how reliably and consistently it will behave.

How does the mechanism work? Is it a GG supported by posts like in the Letus? Is the current model the one with X and Y oscillation tuning? Can the adapter lock Nikon lenses into place? How is backfocus adjusted?

I don't think any of these questions have been answered in either forum. I think potential buyers would like to know these things, so maybe we can gather up the information and make it into a sticky on Dennis' forum.

[Ben Winter]

The Brevis works the same way as the Letus, except it is made of much sturdier material and to much more precise measurements. Practically nothing is made of plastic, and the only glue used is clearly a very strong epoxy of some sort (I'd say JB Weld but that's grey, this substance was black). The GG plate seems to be screwed together and supported by four fairly long, thin metal rods either welded or epoxied at the ends. There are battery cells epoxied to the inside of the unit along with a short bit of wires connecting it to the switch with a resistor, the motor, the recharge plug, and the LED indicator light. The entire unit can be disassembled using an allen wrench.

My Brevis is being returned to me via Canada Post as we speak, so we'll see how the design has changed when it arrives. From what I can remember when I had it, it had no oscillation tuning and although I don't know what you mean by backfocus (the camcorder focusing on the ground glass? Or the distance between the focusing screen and the SLR mount? If you mean the latter the term is "depth of focus.") I'm sure it's very easily adjusted. If you mean the distance between the focusing screen and the SLR mount, it's already correct to a very, very precise amount. Think CNC machined.

From what I have gotten from owning it, it is a very precise workhorse and I wouldn't be surprised if it lasted me many years.

[Marcus Marchesseault]

Ben to the rescue! Now we know how all the adapters work, except for possibly the MPIC. It seems there are the rotating glass and the oscillating glass on posts as the two options. The latter seems more compact. Is there any advantage to the rotating type?

[Ben Winter]

Originally Posted by Marcus Marchesseault

Is there any advantage to the rotating type?

If you so desire, one can use a focusing screen of higher diffusion and still visibly reduce the grain pattern on a rotating setup. A higher diffusion screen on a vibrating type can cause issues as the oscillation pattern may not be enough to dissappear the grain.