Wanted: more latitude at DVinfo.net

Rafael Lopes · July 18th, 2006, 06:31 AM

Hi guys,

Here's the deal, I've been "studying" and trying out 35mm adapters for years. Initialy I was curious about it because of the amazing possibilities of having DOF with digital video, but after years looking at diferent adapters' footage one thing that really stroke me as REALLY amazing is the fact that some of these adapters (particularly the G35 and the Redrocks') seem to increase the cameras' latitude drasticly. Weather the increase of latitude is aparent or real is beyond the point, since when you look at the footage what you see is a very aparent increase in latitude (good enough for me). I'd like to know if there's any other way to do this, maybe even using some of what is being used by Cinemek and Redrock but in a different way, without the adapter, for people who just want more latitude and don't necessarily want DOF.

Tim Johnson · July 18th, 2006, 06:37 AM

ermmm... i think i know what your on about, maybe its down to the ground glass in the adapter?

Rafael Lopes · July 18th, 2006, 06:54 AM

That is what I think it might be too. Either the ground glass or the diffuser but I would put my money on the ground glass. Could it be possible to create a filter to simulate this effect? I tried Tiffens' Ultracontrast but the effect is far from similar and the footage comes out way too pasty. I'd really like to hear from Jonathan (Cinemek) and/or Brian (Redrock).

Tim Johnson · July 18th, 2006, 11:15 AM

i believe it may be also be due to the the condensers in alot of the 35mm adapters, as they help even out luminance if you will...

John Jay · July 18th, 2006, 11:42 AM

If you want more real latitude (without the noise) , perhaps you could persuade the camera manufacturers to introduce a 3CMOS camera with Bayer filters on each. This way each CMOS could be made to expose for the Highs, Mids & Shadows independently effectively giving 10 bit performance within an 8 bit stream which could be expanded out to 10 bit in post.

Rafael Lopes · July 19th, 2006, 04:39 AM

If Jonathan and Brian managed to do it there's gotta be a way to do it, to adapt
it so a screwon filter.

Justine Haupt · July 27th, 2006, 10:36 PM

I think it's the ground glass, hands down. I couldn't imagine a way to reproduce the effect with anything but a mini35, because the image simply has to be projected onto the GG, and than focused into the CCDs. Any filter is completely transmissive (the light rays trace a straight line through the glass), but a ground glass doesn't work this way.

Put simply, if there is a way to achieve the affect you want without actually employing a mini35, than the apparatus would probably be more complex than a mini35, anyway.

Rafael... You said you believe it to be either the GG or the diffuser. Either I'm misunderstading or there's a little confusion. The GG is the diffuser (most GG suppliers actually call them diffusers). Did you mean the condenser? or achromat? Just curious.

July 18th, 2006, 06:31 AM	#1
Rafael Lopes Trustee Join Date: Sep 2005 Location: Rio de Janeiro Posts: 1,240	Wanted: more latitude Hi guys, Here's the deal, I've been "studying" and trying out 35mm adapters for years. Initialy I was curious about it because of the amazing possibilities of having DOF with digital video, but after years looking at diferent adapters' footage one thing that really stroke me as REALLY amazing is the fact that some of these adapters (particularly the G35 and the Redrocks') seem to increase the cameras' latitude drasticly. Weather the increase of latitude is aparent or real is beyond the point, since when you look at the footage what you see is a very aparent increase in latitude (good enough for me). I'd like to know if there's any other way to do this, maybe even using some of what is being used by Cinemek and Redrock but in a different way, without the adapter, for people who just want more latitude and don't necessarily want DOF.

July 18th, 2006, 06:37 AM	#2
Tim Johnson Regular Crew Join Date: May 2006 Location: London, England Posts: 101	ermmm... i think i know what your on about, maybe its down to the ground glass in the adapter? __________________ (Wishes to be more informative and helpful than a nuisance)

July 18th, 2006, 11:15 AM	#4
Tim Johnson Regular Crew Join Date: May 2006 Location: London, England Posts: 101	i believe it may be also be due to the the condensers in alot of the 35mm adapters, as they help even out luminance if you will... __________________ (Wishes to be more informative and helpful than a nuisance)

July 18th, 2006, 11:42 AM	#5
John Jay Major Player Join Date: Sep 2002 Location: US & THEM Posts: 827	If you want more real latitude (without the noise) , perhaps you could persuade the camera manufacturers to introduce a 3CMOS camera with Bayer filters on each. This way each CMOS could be made to expose for the Highs, Mids & Shadows independently effectively giving 10 bit performance within an 8 bit stream which could be expanded out to 10 bit in post. __________________ John Jay Beware *PLUGGER-BYTES*

July 27th, 2006, 10:36 PM	#7
Justine Haupt Major Player Join Date: Oct 2005 Location: Long Island, NY Posts: 208	I think it's the ground glass, hands down. I couldn't imagine a way to reproduce the effect with anything but a mini35, because the image simply has to be projected onto the GG, and than focused into the CCDs. Any filter is completely transmissive (the light rays trace a straight line through the glass), but a ground glass doesn't work this way. Put simply, if there is a way to achieve the affect you want without actually employing a mini35, than the apparatus would probably be more complex than a mini35, anyway. Rafael... You said you believe it to be either the GG or the diffuser. Either I'm misunderstading or there's a little confusion. The GG is the diffuser (most GG suppliers actually call them diffusers). Did you mean the condenser? or achromat? Just curious. __________________ ~Justine "We are the music makers, and we are the dreamers of dreams" -Arthur O'Shaunessey (as quoted by Willy Wonka)

July 18th, 2006, 06:54 AM	#3
Rafael Lopes Trustee Join Date: Sep 2005 Location: Rio de Janeiro Posts: 1,240	That is what I think it might be too. Either the ground glass or the diffuser but I would put my money on the ground glass. Could it be possible to create a filter to simulate this effect? I tried Tiffens' Ultracontrast but the effect is far from similar and the footage comes out way too pasty. I'd really like to hear from Jonathan (Cinemek) and/or Brian (Redrock).

July 19th, 2006, 04:39 AM	#6
Rafael Lopes Trustee Join Date: Sep 2005 Location: Rio de Janeiro Posts: 1,240	If Jonathan and Brian managed to do it there's gotta be a way to do it, to adapt it so a screwon filter.