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-   -   HD Adapter that allows for 35mm cine lenses (https://www.dvinfo.net/forum/techniques-independent-production/2565-hd-adapter-allows-35mm-cine-lenses.html)

Justin Chin June 29th, 2002 02:00 AM

HD Adapter that allows for 35mm cine lenses
 
I found this while browsing the Zeiss website. I can't believe I hadn't heard about this before. Time to save up my bucks...

(link to the actual page, original is set in a frame)

http://www.zeiss.de/C12567A8003B58B9/InhaltWWWIntern/FFF5B7176132C3A4C1256B880050075D#

Chris Hurd June 29th, 2002 07:33 AM

Y'know, P+S Technik is coming out with a 2/3rd inch version of their Mini-35 adapter, for use with HD cameras. "Later this year" is what I heard.

Justin Chin July 13th, 2002 09:07 PM

Yeah, I read that Chris.

It will interesting to see what they come up with. Hopefully a better power and switch set up. Or maybe they'll come up with something that doesn't take 1.5 to 2 stops.

The Zeiss setup actually ADDS 2.5 stops. Now that is super cool. BUT it doesn't have a backend aperture to control that light, so you'll have to use the cine lenses to do that. You'll lose some of the shallow depth of field in that situation.

Don Berube August 15th, 2002 11:05 PM

According to Mizell at ZGC, looks like P+S is hoping to introduce the unit at IBC. There are some prototypes which are now being used on some major productions, with hopes that there will be a DVD of test footage very soon of the PRO35.

Anybody going to IBC with me?

- don

Don Berube August 15th, 2002 11:22 PM

Check this out:
http://www.pstechnik.de/datasheets/d_pro35.htm

Charles Papert August 16th, 2002 12:23 AM

Thanks for posting that info Justin, I'm baffled also that the Zeiss unit was introduced two years ago and I have never heard of it either.

To me, a direct optical path is preferable. The whole spinning ground-glass thing to me is a bit strange.

As for gaining 2.5 stops, that's a real blessing! You can always add ND, either in front of the lens or within the filter wheel on the camera body to open up your shooting stop if desired, although I personally don't ALWAYS want shallow depth of field. However, raising the effective ASA by a factor of 2.5 stops without having to boost the gain is a massive plus and would allow for some amazing low light photography, I think.

Clayton Farr August 16th, 2002 09:24 AM

One thing...

From a quick reading (maybe I missed something) at the Zeiss' site it looks like although this unit allows the use of cine lenses on 2/3" cameras it is 'compressing' (to use their words) the image to fit (and expose directly on) the 2/3" chips (which is accounting for the gain of 2.5 stops).

Isn't this - in function - kind of like the Canon EF (right name?) adapter that causes the focal length of the lenses to change? Zeiss' site even mentions a "Conversion Ratio of 0.404" (or 1:2.5).

Do I have this right? Also how would this 'compression' and perhaps the increase of focal length it would cause affect the available range of DOF?

Its been a long time since I've played with the Canon lens adapter on the XL1, but I recall it being pretty limiting in terms of focal length (although the conversion factor wouldn't be as high here) and not being able to use the full focal range on zoom lenses.

I can't remember if one gained the DOF benefits of the 35mm lenses or not with the EF adapter - but I'm guessing no since it is exposing directly to the CCD and thus why the much more expensive P+S Technik unit is preferred.

So is this Zeiss unit just a fancy version (conceptually) of that?

What are your thoughts/understandings?
Clayton

Justin Chin August 16th, 2002 12:30 PM

ClaytonF:
From what I understand the adapter just brings the image down to the size of the CCD (the conversion ratio you mentioned). This is so you can use the full focal length of the 35mm lenses.

The EF adapter does not do this. It just projects the plane OVER the CCD. The result is you're getting only the center portion of the image and not the complete focal length. Hence the telephoto look with using the adapter.

Now if I'm wrong about the conversion ratio than the CLA 35 adapter is not as effective as I would hope. A quick check on my Mark V viewfinder confirms their focal length table. So it appears you get the full FL.

Charles:
A lot of things are baffling me these days. I come across many people who poopoo the idea of using 35mm lenses (specifically these adapters). Lots of, "That won't work", "The 35mm lens coatings are not compatible with the HD format", "Why would you want to do that?" blah, blah, blah. Of course none of these guys I've talked to have never actually seen the results. I think there are people (video people) out there who just don't understand the desire to have 35mm DoF. This has probably kept these adapters out of "mainstream" use. Remember the mini35 has been out for 2 years as well and I still don't hear about many productions using it or image samples.

The 2.5 stop gain is really huge! I found the low light level of the 900 is already damn amazing on some test shoots. I would prefer to use the filter wheel for slowing down image. I just hate putting things in front of the lens, I'm just a freak that way. Do you know if you can slow down the image with the paintbox? I believe you can. I didn't get that far in the manual.

As for the ground glass, yes it's funky. I have a love hate relationship with it. At first glance of the pro35 I see no power switch. Does it receive power from the camera? That would be cool. I also don't see a focus pin on the unit.

I got word that the Pro35 is around $27,000 and the CLA 35 is $23,000.

Don Berube August 20th, 2002 02:09 AM

Shot with the Mini35
 
"Phreakers" received a lot of attention recently at the Atlantic City Film Festival.

http://www.indieclub.com/q&a/phreakersqa.asp

- don


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