Extreme Vs Brevis

My biggest beef with this setup is that once again, screw pressure holds the whole rig up. Even a stock cavision system is like this. No good says I.
 
Dennis Wood said:
Well, this in one configuration I hadn't seen yet by just flipping the rear mount over :-) There's such a huge variety of ways to configure these. The scratching is not an issue structurally, which is why we use a very heavy wall spec for the tubing. That said, we've got something very interesting coming in the carbon department that ups the stiffness factor over stainless by 75%, is still half the weight, and can be used to beat off thieves.
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Hi Dennis,

Yeah, I set up the same way (flipping the rear mount over so the 5/8" support is higher off the rods). I also find it allows the bottom tripod mount to have more mobility up and down the rods (especially when using a large manfrotto tripod plate). I really like the flexibility of this unit. The only thing I've noticed is that the rods have some small/minor flexibility (in other words, there is some up/down play in the rods even when tightly clamped down; possible due to the nature of carbon rods). I plan on trying out my M2 rods (steel) to see if the play is gone; however I do like the light weight of the Cinevate rods.

Soooo... you have something interesting coming in, huh? New rods? Looks like time to get the old, worn, trusty, near maxed credit card(s) out again :laugh: Would love to hear more, especially about a time frame they will be available! I want! I want! I want! Boy, am I needy....
 
"BTW a mattebox and N.D filters are needed to bring out the best of the image using an adapter. "-DavidChia

Can somebody explain this to me? I don't understand why. I don't quite understand why we need a mattebox or N.D. filters. Why not just use the camera ND filters? I know you guys know what you're talkin about, I just want to learn.
thanks.
 
The point is not to over expose your G.G . So you need to cut the light before it reaches the G.G not after. When you closing down the 35mm lens, gain will start showing up . Hence you use N.D to control the expose of the shot with your 35mm lens wide open and maintain the camera F stop around f5- f8 to get good video quality.

But some lens are abit soft when the are wide open, so you need to check your lenses for softness too.
 
thanks, that's great info!
so, you want 35mm lens f1.4-f4 (?) and video cam at f5-f8, and never use the video cam's ND, and that should be a good guide for when to use an ND in front?
i appreciate the help!
 
try to keep the 35mm lens low as possible. At f2.8 gain starts showing up on static adapters, and some vibrating adapters in certain conditions also show gain at f2.8- f4. It depends on the lens and glass coating , blades the lens have and also lighting condition of the whole shot.

The best way to see how your lens behave , is to do an experience at home with the output to the biggest TV you can hook it up with and start playing with the F stops and see for yourself when the gains start showing up.

It doesn't matter if your home TV isn't HD, as long as it is bigger then your LCD on your camera.
 
Great thanks!
I think I'm gonna go for this set up for my HVX: RedRock FF, Cinevate Rails, and Letus Extreme. I will add a Mattebox when I have the money. Can anyone foresee a problem with this or a better alternative.
For somebody with Cinevate Rails, is there a pin near the screw to lock the camera base in place. I mean, on my tripod head there is that little pin that keeps the camera from moving but I can't see one in the Cinevate pictures.
 
Yes Berry,
that's what I was thinking, too.
So - why does everybody has a matte box with their adapters?
Isn't it chaper to use screw-on filters (if you ever need any).
I admit it looks better...:-)
 
David, Do you mean "grain" here instead of "gain".

Also If I had to use an adapter with my video lens closed down to to f5-8 , I'm sorry but I'd have to chuck the whole damn thing. If you're outside fine, but inside - where do you guys get your lighting budget from. Its cheaper to rent an F900 than to light to those levels.

You should be able to use your adapter with decent edge to edge focus absolutely wide open on your video camera. It may be marginally better at 2.8 or more but it needs to be acceptable wide open or else its just not economically feasable in production. I think most of the newer adapters can do that fine.

Also I concur with Barry - never have seen one example of an overexposed GG yet and I've been asking for months. Makes no sense to me. I'm open minded though - just show me the pictures. "Where's the Beef" guys?

Lenny Levy
 
berlinfool said:
So - why does everybody has a matte box with their adapters?
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To keep stray light from entering the lens and washing out the contrast and introducing flare into the image.

Matte boxes also provide standardized 4x4 or 4x5.65 filter slots so you can use one set of filters on every camera. Screw-in filters are only good for one particular thread diameter, and they're much more of a hassle to put on and take off, and if you need to use 'em on different-sized lenses you need step-up rings or step-down rings, and step-down rings can cause vignetting, and on and on. They're a cheap solution, but not really a professional solution.
 
Lenilenapi said:
Also I concur with Barry - never have seen one example of an overexposed GG yet and I've been asking for months. Makes no sense to me. I'm open minded though - just show me the pictures. "Where's the Beef" guys?
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There's no pics because the issue doesn't exist.

Didn't I post pics of when I disproved this? I can't remember... but whether I posted pics or not, I went about to disprove this silly claim. I set up a shot with an adapter, set at a certain low light level so the camera iris was fairly wide open, and took a shot. Then I increased the light level by 256 times (256x as much light!) and put in both camera ND filters, and stopped down the in-camera iris by two more stops, until I got equivalent exposure, and took a shot of that. Compared the two -- they were *identical*.

There is no truth whatsoever to any concept of "overexposing" a ground glass. Surely, at 256x as much light, the ground glass would have "overexposed" if that was possible, right?

Heck, try it yourself. Put your shutter on 1/2000, put in both ND filters, and then go point the camera at the noonday sun. If the ground glass was ever going to "overexpose", it'd do so by being pointed right into the sun, right? But it won't. Because such a concept makes no sense.

If anyone's noticing any difference when using internal vs. external ND filters, it'll be due to some other factor (such as that they're using a cheapo camera that has lousy-quality ND filters maybe? or they put on a matte box to use the external NDs, but didn't bother to flag stray light off the shot where they didn't use the matte box?)
 
If I don't want to put a MatteBox on my setup, and I wanna use the Cinevate rail system and Letus Extreme on my HVX, could I get away with using the 12" rods, instead of 18"?
I'm also still interested if the base plate comes with a pin next to the screw to secure camera better.
thanks,
ns
 
Thanks for the re education guys,

The camera records from the G.G . So I always thought the one should control the image before it hits the G.G and not after it. Isn't it better to tune the image and get the best out of it before the G.G .

You are saying that it is O.K to cut down after the the aerial image has been allowed to pass through from the G.G before it hit the CCD. Isn't light an issue to the G.G if the image is too bright to begin with?

If anyone's noticing any difference when using internal vs. external ND filters, it'll be due to some other factor (such as that they're using a cheapo camera that has lousy-quality ND filters maybe? or they put on a matte box to use the external NDs, but didn't bother to flag stray light off the shot where they didn't use the matte box?)
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Maybe you are right, I need to check my DVX and XHA1 filter or maybe it is me not paying attention to flag the light away. Which I think is most likely.

David, Do you mean "grain" here instead of "gain".
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Yes I meant Grain not gain.
 
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This is an interesting discussion, as using external ND filters to control the incoming light before the GG, is a practice commonly preached in the 35mm adapter world (forums). This is actually the first time I've heard anyone say otherwise. Anyone care to challenge the argument?

Obviously, if David, myself, and I'm sure many others have been under this impression, there must be someone who has proof/experience/whatever to support this. Otherwise, its strange how this practice has become so widespread.
 
hmm, it makes more sense for the GG to get as much light as possible to eliminate any visible grain problem? No ? Then cut the light down in camera? No ?...
 
Here is a brief personal POV/practice:
The operator KNOWS before hand the "look" he wants. He knows the lens (wide, normal, etc) AND the DOF he wants/needs for the shoot.

Say he wants the look of a 35mm at 2.8. He has a 35/1.4 lens.

Outdoors/daylight. The light level hitting the GG through that lens at 2.8 will require a reduction of the light level. He will stop down the camcorder's iris to a 4 or 5.6 first.
If that's not enough, he will use one of the internal ND filters and if that is still not enough (I doubt it though) he will change the shutter speed. All the camcorder changes will adjust the amount of light required for a proper exposure but will not change the "look". (I have noticed very few external ND filters coated and that is why I would prefer to use the internal ones). I am talking about the squared ones

http://www.formatt.co.uk/wfWebResou...M2MDY2NTguanBn&h=MTIvMDYvMjAwNyAyMjoxMTozOQ==
(for MB), not the still photography filters
http://www.hoya-online.co.uk/index.2.jpg

. My 2c.
Cheers,
Dan
 
is a practice commonly preached in the 35mm adapter world (forums).
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Just because something's accepted as "commonly known", that doesn't make it true.

I've disproved this notion, anyone with any knowledge of optics will know that this "overexposing the ground glass" stuff is inaccurate, and Lenny and I have been asking for someone/anyone to offer any evidence to the contrary. None has surfaced.

Don't know much more what we can do. The notion is wrong, it's been disproven, so now it's up to you guys to start challenging those who say/repeat it.
 
Oh I'm not disagreeing with you. It's good know that we've been mislead. I learn alot off these forums, but its lesson learned that its up to oneself to filter (internally or externally - ha, sorry i had to :) ) out the inaccurate information...... even if its commonly said.
 
shortnstout said:
I'm also still interested if the base plate comes with a pin next to the screw to secure camera better.
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You mean like a locking pin? I don't see one on my base plate.

taormina said:
My biggest beef with this setup is that once again, screw pressure holds the whole rig up. Even a stock cavision system is like this. No good says I.
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Says me too. I really don't like how the weight of the camera is held up by horizontal screw pressure so I'm flipping the adapter instead.
 
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