B4 mount 35mm DoF adapter options

M

Marshallarts

Well-known member
Apologies for needing to post for this but these forums (to me) become so disorganized with information overload / opinions / speculation / wishing, that I loose information on actual facts as soon as I learn others.

I need a 35mm DoF adapter for a Sony F900.

From what I can find my only options are the Pro35 at the moment and only rumors of a Letus coming.

Are there any updates to the Letus you've heard or do you know of any other B4 2/3" mount adapters I could use?
 
Check this out:

http://www.dvxuser.com/V6/showthread.php?t=154680

My most fresh demo footage is:

http://vimeo.com/2730291

With Varicam and F900R you can use the invert function to flip the image... The pros are, that you have better optical perfomance since less glass comes into the path of light, on axis system (not like a periscope) and the cons are, that is a bit longer than the periscope style flip modules...

But you can choose a SG-Blade with my relay and have the overall size of Pro35 but with periscope style... like Pro35...

The relay, is available...
 
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thank you for the replies.

I've never heard of the SGBlade... (where was I when that came out?)
Good to hear the Letus may be coming out soon and thanks Achillopoulos for the straight relay recommendation. I've actually used an early Nikon straight relay adapter (minus the DoF adapter) on a F900 before. It appears such relay lenses have been out awhile now since the rental house I got it from said it was from the early 90's. I thought he said ~$10,000 back then or something, may be wrong.

Makes you wonder why it's taken so long to have them readily and widely available and with a DoF element to it. P&S Pro35 must have been RACKING it in all these years because they're the only one I knew about until now!!--and they rent $400/day!!! Were there any others all this time?

So now my options are:
P&S Pro35
Letus B4 Relay (is this just the relay or will it be a DoF adapter?)
Motion FX GG.Relay rev2 (but that's just the relay right?--because it says GG and I didn't think ground glass was in a relay thought I could be wrong--you still need the adapter and in the FAQ it says Letus35 and SGBlade but NOT Brevis, it says "EXCEPT from Brevis35" which is odd because isn't that a Brevis pictured attached to it???)

In the links you've provided it appears Brevis/Cinevate planned on having an adapter too, soon I guess as well.

There's also that mystery Nikon Relay adapter I used before but truthfully I'd prefer to just have a one unit Relay/DoF adapter.

Anyone else?
 
The reason it's taking so long is that while some are using "rebranded" macro lenses, we've found this solution lacking particularly in edge to edge resolution. So basically a relay that's up the Scarlet 2/3" chip specification, or even native 1920x1080 chip resolution, must be designed from the ground up with complete custom glass. To do it right has meant a huge investment in R&D, and now well over a year of development.

The Cinevate 2/3" relay is the only multi-format 2/3" relay that we're aware of anywhere, at any price. This means that you'll be able to put an SLR or cinema lens out front and use both with zero crop factor. The unit uses 11 internal elements, most of LD spec glass using very interesting coatings. This was done to bring contrast and MTF values in line with even very high end Zeiss glass. Price is still pegged at $2500 for the relay. This relay is designed to work with all REV2, MP.1 and (soon) MP.2 flipped adapters that we've sold over the last two years...meaning we've leveraged our customer's investment with us :-)

Cheers,
Dennis.
 
Marshallarts said:
I've actually used an early Nikon straight relay adapter (minus the DoF adapter) on a F900 before
Click to expand...

A straight relay was also the Angenieux CLA35... this type of "straight relay" have a big difference from the GG.relay/Brevis35 combo...

The Angenieux type its purely optical B4 to PL mount adapter, that means it does NOT HAVE the DoF of 35mm... so they were just a FoV adapter with the DoF of 2/3 and not the DoF of 35mm like Pro35 has.

The GG.relay/Bravis35 combo it is straight because there is no prism to flip the image because we use the "Image invert" function of the camera. It is for the better, to don't add more glass in the path of light, since cameras like Varicam and F900R have such a function.

The GG.relay/Bravis35 combo has the DoF of 35mm as the Pro35 does.

So the GG.relay/Bravis35 combo its NOT like the early days "straight relays" like Angenieux was...

Marshallarts said:
Motion FX GG.Relay rev2 (but that's just the relay right?--because it says GG and I didn't think ground glass was in a relay thought I could be wrong--you still need the adapter and in the FAQ it says Letus35 and SGBlade but NOT Brevis, it says "EXCEPT from Brevis35" which is odd because isn't that a Brevis pictured attached to it???)
Click to expand...

Thats the language barrier... the "except" was on the "question"...

So I replace the "except" with "apart"... the original FAQ becomes:

Q. Will it fit to any 35 adapter i.e. Letus35 or the new SGblade, apart from Brevis35?

A. Yes, the relay has a filter thread of 72mm so it fits with all adapters. The new design has adjustable focusing and can fit to all adapters, especially in the 36mm x 24mm size.
Click to expand...
And the "GG" stands for GG (adapter) relay...
I didn't thought that the name could lead to this misleading... the relay is just a relay... no ground glass inside...

Marshallarts said:
Letus B4 Relay (is this just the relay or will it be a DoF adapter?)
Click to expand...

I can understand that you have a misunderstanding of what a relay is...

A relay is a macro lens that it happens to have a B4 mount and it is optimized for 2/3 3CCD cameras...

A DoF adapter is the device that incorporates a ground glass that is either spinning (SGpro, SGblade, Letus Ultimate) or vibrating (Brevis35, Letus Extreme) or its static (like G35). these devices are designed to fit in front of a lens, mounted on the filter thread. As it is widly known these devices are designed to mount in small cameras like HVX200, in which the lens is attached permanently so a relay is not needed.

Because these cameras don't have an image invert function, we add the flip module (a prism).

In order to connect these adapters to a B4 mount camera you need a relay.

So we have apart from the 3CCD 2/3 camera: a relay > invert prism (flip module) > 35 adapter (with Ground Glass) > 35 mm lens mount.

This is the Pro35 in one piece.

Alternatively you can buy, a GG.relay, a flip module, and an SGblade (or Letus or Brevis35 or G35) (the lens mount is included in the ground glass adapter).

Or a Letus relay (or a Cinevate relay), a flip module, and an SGblade (or Letus or Brevis35 or G35) when these relay's will be available to order.

All the above are equivalent to a Pro35 (I will say much better than a Pro35) with the 1/3 to 1/5 the cost.



Marshallarts said:
truthfully I'd prefer to just have a one unit Relay/DoF adapter.
Click to expand...

Its good to have separate the relay and the adapter, because in some point you can change the adapter or the relay... the relay front is like an HVX 200 front lens with filter threading...




A different subject...

Its also possible that you have misunderstand my postings because apart from the relay tests, I have an R&D project with a new technology "ground glass" that it is a FiberScreen. It is an imaging element that has no grounded side so it doesn't diffuse the image and it is grain less... I test this screen with the Brevis35 adapter along with my relay, so probably I confuse you by mentioning the ground glass also in the tests...
 
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Dennis Wood,
Is the Cinevate Relay out now!?!? It's not on the website--any idea when? It's great you've taken to the time to get it done right especially in terms of it's sharpness.

Something I've never considered: The relay is to adjust the FoV from the 35mm to fit the 2/3" giving a zero crop factor. But wouldn't a full frame still 35mm lens and a cinema lens (the smaller APS sized academy35) have different FoVs? So how does Cinevate manage a multi-format relay in practice?

Either way I'm very glad you're doing it. As I said before P&S really had a monopoly. Why do they charge so much?!! I guess the technology has been out awhile-- as I said I used a Nikon relay from the early 90's. It's good there's finally some competition!


Evangelos,
thanks for taking the time to clear that up, but we were on the same page, just a misunderstanding. I figured the GG was just a "straight relay" requiring the DoF adapter if you want 35mm DoF (ie. the GG.Relay/Brevis35 combo). On the Nikon I used I had only a 2/3" DoF as you mentioned because I didn't need the shallow DoF and didn't get the DoF adapter--I only used it to get a super wide ~3.5mm equivalent using a Nikon 15mm lens for some shots (our lens is only 4.5). The other option was to go with the Pro35 and have the relay & DoF adapter in one but we just didn't need the DoF and it costs 3x the amount.

And I was just making sure the Motion FX needed the DoF adapter since having GG in it's name I jumped the gun assuming it has ground glass in it--further confusing myself since it has the Brevis on it in the picture. That's just me thinking too far ahead.

As for relay vs DoF adapters. I understand what you're saying. I just refer to them as two separate units. When asking about the Letus, "Letus B4 Relay (is this just the relay or will it be a DoF adapter?)" I was wondering if it is just the relay or if it will be a Pro35 type all-in-one unit.

In my experience, anytime I've needed a relay to use a DoF adapter (because as you say there is no lens to directly attach a DoF adapter to on the camera) it's ALWAYS been the Pro35. So I'm always assuming B4 mount DoF adapters will be all-in-one units.

I'm very curious about your new Fiber Screen!! Sounds really great! Be sure to keep us up to date.
 
Marshallarts said:
The relay is to adjust the FoV from the 35mm to fit the 2/3" giving a zero crop factor. But wouldn't a full frame still 35mm lens and a cinema lens (the smaller APS sized academy35) have different FoVs?
Click to expand...

I will answer my perspective... GG.relay has two different versions, one for FF35 and one for S35... so the image sizes are, for FF35 35mm x 23.4mm and for the Super 35 24mm x 13.5mm...

GG.relay is a macro prime lens optically optimized only for macro with very flat focus plain, minimal CA, maximum MTF and in use with 3CCD sensors. So the lens can't focus in to infinity...

One more thing, its understood that you can't attach a 35mm lens directly on the relays... neither GG.relay nor Cinevate's or Letus... its compulsory that you will use them with an adapter...

Marshallarts said:
I'm very curious about your new Fiber Screen!! Sounds really great! Be sure to keep us up to date.
Click to expand...

Check this link http://vimeo.com/2730291 is a test video that I loaded to Vimeo in order to test Vimeo's color reproduction... its being shot with the GG.relay and the new FiberScreen on Brevis... the full length video will be up on Monday... it will include skin tones and stop down to F16 test...
 
Evangelos, that's not quite correct. Our one relay is designed for both frame sizes. It is designed with an internal zoom that fully covers the 35mm cine, and 35mm SLR frame sizes. This is what makes it very unique, and in our opinion, pretty amazing for $2500.

This means that a 17mm SLR lens will be relayed to the camera with zero crop factor and 100% FOV.

It also means that a 17mm cine lens will be relayed to the camera with zero crop factor and 100% FOV.

We provided a cine type locking aperture (no detents), and a locking adjustable back-focus. That's why it's taking so long :-) As for direct relay and other lens options...assume nothing! We've got a few more surprises in store. M, the relay project is definitely behind schedule so I've stopped providing dates. That said, we're expecting to have some interesting gear with us at NAB :-)

Cheers,
Dennis.
 
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Dennis,

Will your relay have 72mm threads so it is compatible with other adapters? That would be very nice.
I may have asked you this before and am anticipating that it is optimized for a very specific distance to the GG, regardless of whetehr it uses threads or not.


Lenny Levy
 
Dennis Wood said:
Evangelos, that's not quite correct. Our one relay is designed for both frame sizes. It is designed with an internal zoom...
Click to expand...

Dennis I was referring to my relay...

I will answer my perspective... GG.relay has two different versions, one...
Click to expand...
And as of:

Dennis Wood said:
This means that a 17mm SLR lens will be relayed to the camera with zero crop factor and 100% FOV.

It also means that a 17mm cine lens will be relayed to the camera with zero crop factor and 100% FOV.
Click to expand...

My relay has two setup's one for SLR lens and one for Cine lens so zero crop factor and 100% FOV... but its not a zoom... so two optimized fixed distances from GG's

Also it has adjustable iris with clicks from F2.8 to F8, and adjustable focus...
 
Dennis,

Can I interpret that as - yes 72mm threads and it will be able to focus but only in a limited range which may or may not accomodate other adapters.

Bring it on Dennis
Lenny
 
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