Inital Thoughts?

[DJ Lewis]

So, out of the box, what do you think? Was there a 'wow' factor? (or gut wrenching dissapointment for others)....

Were they everything you thought? Was it easy to set up? Easy to adjust the mounting flange and back focus? What was your first reaction when you started shooting?

[Rafael Lopes]

I wanna see some freaking beta tester footage

[Andy Gordon]

Unfortunately I am disappointed. I’ve been building my own adapters for over a year, first static then oscillating so I had pretty high expectations and I know exactly what I want from an adapter, and I was nearly there with my own oscillator when I decided to buy the Brevis because I thought Dennis had solved the final problems I was struggling with.

The lens mount adjustment for correct infinity focus could be better. It’s difficult to ensure the lens is on a parallel plane to the GG, the surface the screws press against should at least be flat but it has grooves in it. When you tighten the screws the mount gets pushed out of line. What's the point in having micrometer accuracy on everything else if the final lens alignment relies on how the grub screws sit against the grooves on the lens mount?

There’s no adjustment on centering the already small GG on the centre of the camera’s z axis which means further reduced field of view when you have to zoom in to get all four edges out of shot. The centre of the GS400 is not in line with the Brevis GG centre which means some wasted image area.

Furthermore the blobs of glue/tabs mounting the GG encroach onto the GG by a good mm on each side again reducing useable image area. The glue appears to have run or been rubbed into the fresnel grooves somewhat as well, and the diffuser has scratches near the edges.

The real disappointment for me is the bokeh. It’s bad bokeh... I took a risk jumping into the beta group without seeing a rack through a point source of light, but Dennis assured me there was no haziness when I specifically asked him about it... Here’s two comparison shots between my own adapter (POC 20 degree diffuser plus 2 x 120FL condensers) and the Brevis.

Brevis open aperture bad bokeh:
http://imagedump.filefactory.com/full.php?id=7341

POC20 open aperture comparison good bokeh:
http://imagedump.filefactory.com/full.php?id=7342

Brevis F4 better but still bad:
http://imagedump.filefactory.com/full.php?id=7343

POC20 f4 comparison good bokeh:
http://imagedump.filefactory.com/full.php?id=7344

The Brevis has hazy bokeh until you stop the lens stopped down to f4 or higher. Even then it's not as good as it should be. With the lens fully open it has the same characteristic haziness you get with a Beattie. It looks like the same type of diffuser with a fresnel, and the bokeh looks identical to the results I got with the Beattie.

Sufficient diffusion is a trade off against light loss, and since Dennis has also tested the POC 20 degree diffuser I find it hard to believe he didn’t prefer the bokeh of the POC… the light loss is about the same as the Brevis but the diffusion is better. Maybe it has too much grain, that's the final hurdle I haven't got over with my adapter, it doesn't move fast enough to eliminate the grain. The thing is, insufficient diffusion also increases the apparent depth of field, which is not what we want, and the DOF on the Brevis seems deeper than my adapter with all settings being equal.

Another let down is the noise of the Brevis - it's ok with the camcorder's own mic but the Rode videomic doesn't like it. A lot of bass rumble comes through even with the low pass filter on. Plus the end of the mic is right above the Brevis motor. Camera mounted mic is not an option with the Rode.

I'm sure plenty of people will be thrilled will the Brevis, but for me the bokeh is a disappointment considering the research Dennis has done. If you want your background lights/highlights to turn into nice discs of light like they do in the movies you need a sufficiently diffusing GG.

Sorry to be so negative Dennis, these are my first impressions, after specifically asking you about the diffusion of the bokeh I feel a bit let down...

[DJ Lewis]

I was concerned about haziness too... my biggest worry actually.... But I can't even begin to form an opinion because I can't get past what I'm dubbing "the red dot syndrome".

Anyone else experiencing it? If you are, you know exactly what I'm talking about. It's probably an easy fix.... (small amount of duct tape maybe?)

Andy, do you find the bokeh completey unusable/way too hazy? Or is it as acceptable as the lo-lux version of the G35? (hopefully you've seen the diffrence)

[Aram Bauman]

My initial thoughts were that it looks good compared to what I have seen like that letus35. I still have to get a lense but i tried to focus on the GG without one and couldnt do it with a 6 closeup lense on the DVX. I cant seem to find the PDF with the info we needed to set up the adapter though but I like the way it looks. Would milling the screws flat fix that problem you are talking about? The disks of light thing doesnt bother me as much and if i wanted them I could just shoot without the adapter and blur in post which im used to.

[Andy Gordon]

Sorry man, but if you're happy to blur in post why did you buy an adapter? Blurring in post with a gaussian blur does not give the discs of light I am talking about. The discs are an indicator of correct diffusion. Insufficient diffusion affects all of the out of focus areas of the image. A lot of people seem to be happy with the hazy results you get from a Beattie or an Optosigma, I am not.

I haven't seen the G35 lo lux vs hi lux. The bokeh looks pretty hazy with the lens open. I'm not happy with it. I tried adding a circ pol (don't have any NDs) but it still looks hazy, and that's not really a solution for indoors when your cam is on open aperture already.

Not sure what red dot syndrome is... I'm guessing bleed through from the power LED? I haven't noticed it.

[Brandon Rice]

I have a problem with my DVX. I cannot get a back focus on this thing, even with a +10 macro. Also, the adapter itself is really easy to fall off the camera.

[Rafael Lopes]

I wish Dennis was here. This is not good news at all

[Rafael Lopes]

I wish Dennis was here. This is not good news at all

despite of it all I think everybody should keep these opinions here at the beta tester forum like Dennis asked. I'm sure Dennis will come to the rescue soon.

[Brandon Rice]

It seems like there should be more threads to screw on the Brevis. I am sure others are working fine.

[Francois Poitras]

Too bad you don’t like the bokey, Andy. But I think it’s fair to say that bokeh is a subjective matter. A guy using an HVX recently posted a clip using a G35 with the lo-lux GG, showing a very obvious lack a diffusion, which gave an aerial image around objects in the bokeh. A lot of folks thought the SDOF in that clip was truly awesome... So some folks are happy with very little diffusion, some just want enough bokeh to draw the attention of the viewer on the subject in focus, while others specifically want halos around lights, and that’s OK.

There is no such aerial image with the Brevis diffuser.

The POC20 alone has greater diffusion, but the grain is visible in certain conditions and, if you don’t use an extra condensor lens, you get twice as much light loss (and still).

[Joshua Nitschke]

The adapter looks great and pretty solid; although the support seems pretty cheap. (Rails look great though)

I haven't fooled around with it since I don't have any achromats, so I can't say anymore beyond that. Still waiting for the ones Dennis will send out.

Andy, I think your sharp bokeh is really distracting.

[Steve Strickland]

I finally picked mine up today. Luckily, everything is in perfect order. I see what people are saying about the mounting screws. It almost seems like, since the mounting ring sits in there so snug, the screws aren't completely necessary. On the other hand, that's why I paid someone else to build one for me since I know zero about the assembly process.

I'm having a pretty hard time lining the diffuser up. It is also not totally center through the lens of me DVX. Hopefully, with the help of the achromat, it won't totally matter.

On the bokeh issue, I was also a little bummed about the softness. I think the hard-edged, or good bokeh, mimics film more closely.

All these issues aside, the construction seems solid to me. It looks great on my Cavision rails. When I get another step-up ring for my matte box, the rig is gonna be down right intimidating.

I look forward to see everyone's initial tests. I hope to put some footage up this week with my cheap macros. Peace...

[Francois Poitras]

Just to add to the bokeh discussion, here is an example of what I personally find quite good enough for diffusion.

diffusion example

It is not a Brevis, but my own vibrating adapter with the exact same diffuser as the Brevis. Shot with a Panasonic GS400, 35mm lens at F4. Sorry for the shaky focus pull.

In theory, the results should be comparable if not better with a DVX or other higher-end cam...

Cheers,

[Aram Bauman]

Well I found my PDF and it says i should have a charger in my box but I dont. The radio shack remote control car charger is what ever is is and probably I shouldnt use it. At this point im not worried about bokeh, Im sure I can simulate it if needed in post.

[DJ Lewis]

Well I found my PDF and it says i should have a charger in my box but I dont. The radio shack remote control car charger is what ever is is and probably I shouldnt use it. At this point im not worried about bokeh, Im sure I can simulate it if needed in post.

If you recall in the shipment section, Dennis stated that the charger would be drop-shipped to you directly from the vendor. I recieved mine this morning, and am sure you'll recieve yours soon...

[Andy Gordon]

Too bad you don’t like the bokey, Andy. But I think it’s fair to say that bokeh is a subjective matter. A guy using an HVX recently posted a clip using a G35 with the lo-lux GG, showing a very obvious lack a diffusion, which gave an aerial image around objects in the bokeh. A lot of folks thought the SDOF in that clip was truly awesome... So some folks are happy with very little diffusion, some just want enough bokeh to draw the attention of the viewer on the subject in focus, while others specifically want halos around lights, and that’s OK.

There is no such aerial image with the Brevis diffuser.

The POC20 alone has greater diffusion, but the grain is visible in certain conditions and, if you don’t use an extra condensor lens, you get twice as much light loss (and still).

Whether you like it may be subjective, maybe you like the promist look, but the hard bokeh is what film cameras produce and that is what corret diffusion looks like whether you like it or not. I hope Dennis has more to offer than "too bad you don't like it", cause I wouldn't have bought the Brevis if he hadn't told me specular lights have no haze when they're out of focus. When you open the lens from f4 to f1.4 you can see the aerial image expand around the highlight, so there is aerial image coming through. Like I said before, because of this the apparent depth of field is deeper with the Brevis than it should be.

So add to that, if I have to shoot at f4 to get non hazy bokeh the end result is quite a deep depth of field. And your light loss also goes to pot if you are forced to stop down the lens!

If you think hard bokeh is distracting go and watch Kiss Kiss Bang Bang. It was beautifully shot with very shallow DOF and hard bokeh throughout.

[DJ Lewis]

Do we know when Mr. Wood is supposed to be back?

[Francois Poitras]

I think Dennis is coming back by the end of the week.

Cheers,

[Joshua Nitschke]

Whether you like it may be subjective, maybe you like the promist look, but the hard bokeh is what film cameras produce and that is what corret diffusion looks like whether you like it or not.

Film lenses maybe, since bokeh is dependent more on the lens than on the acquisition format.