Split-6

[Paul Bruening]

Hello Ladies and Gents,

 

I'm still mulling over a way to cheat contrast in daylight exteriors. While offset, dual DI of each frame digitally filtered and composited would yield results, dual exposure on the film stock would do even better. Originally, I considered a dual techniscope frame. Most DPs find the 2-perf frame too small. So, I'm now thinking about a dual 6-perf frame. Both images would be scanned at the same time and then processed and combined digitally in post. This would cost half again more in stock and processing but would put the DI scan costs back to single scan per frame instead of two scans per frame. This yeilds a thicker negative in the subject's dark areas. The 6-perf frame is almost as big as a Super 35 frame. Actually, when compared to S35 cropped to scope, the 6-perf split frame is a tad bit bigger than the S35 film area. So, image quality would be high enough in most DP's book.

[John Holland]

Wow this idea of yours is just to deal with contrast in daylight exteriors ? Lost me completely i might be a bit thick but what are you on ? :rolleyes:

[Andrew Koch]

This seems like a very expensive alternative to using a 20 X 20 Griff or even some lights. I guess you could use this technique for extremely wide shots where it is physically impossible to create enough fill for the sun. I have no intention of bashing your idea, but I would be interested in how you see this working practically on set and how this would be cost effective and save time overall. (If I were a producer, I would have concerns about a Cinematographer that would require me to spend more money on film, more money on processing, more time in the DI and more work for the compositor)

 

Do you see this as being something that could be done for specific shots rather than the whole project. In that case it might be a reasonable thing to do if there is no way to light it. I am trying to figure out how you would expose two images at the same time? Would you have some sort of beam splitter?

[Bob Hayes]

This sounds like a pretty complicated system. But Paul might be on to something regarding doing two exposure passes. I read an article about enhancing digital photography. The photographer shot a scene with a late afternoon sky that was very bright. There was no way to get exposure in the sky, even with grads. So he shot two exposures, one for the sky and one for the foreground. There is a cool program that lets you combine these two exposures in one photo and be very selective as to what you use from each. The look was magical.

[John Brawley]

This sounds like a pretty complicated system. But Paul might be on to something regarding doing two exposure passes. I read an article about enhancing digital photography. The photographer shot a scene with a late afternoon sky that was very bright. There was no way to get exposure in the sky, even with grads. So he shot two exposures, one for the sky and one for the foreground. There is a cool program that lets you combine these two exposures in one photo and be very selective as to what you use from each. The look was magical.

 

Hi bob..

 

It's not that new an idea. it's called HDRI.

 

http://en.wikipedia.org/wiki/HDRI

 

jb

[Andrew Koch]

Hi bob..

 

It's not that new an idea. it's called HDRI.

 

http://en.wikipedia.org/wiki/HDRI

 

jb

 

This is fairly simple because we are dealing with still images. The question I have is how would you do it with a moving image? You would have to expose the two images at the same time. If you were to use some sort of beam splitter, the speed of your film would probably be cut in half (I say probably because I am not sure about this one)

[Paul Bruening]

Yes. The simplest way with the least interference on the image is to use a 45 degree, half silvered mirror. Half the light passes through to the film plane. The other half goes to an opposite full mirror at 45 degrees to project onto the other space on the film plane. In this way, the image is captured by the single lens first and is distributed to the two film locations. One image will expose at half the ASA of the film, so, the lens will have to be opened up just to compensate for that path. The other path will have the ND (changeable, preferably) filter. The exposure will have to be altered additionally to make the difference on that path. Which means, the correct exposure will be on the ND+1/2 light path so that the other path will pass more light appropriate to it's 1/2 light value. The goal is to get two, identical images with one image a normal exposure and the other a thicker negative to increase the image data available in the subject's darker areas. It goes without saying that this is more useful in the abundant light of daylight exteriors. Artificially lit scenes would require a heck of a lot of light to make this system work. If you have that much light on hand, then you don't need this system. The whole idea in this was to increase productivity on daylight exteriors. I could see its usefulness on a western that was shot mostly outside during harsh sunlight. You could get shots that looked like massive artificial light was providing fill light with no one spending time or money to set up the lights and power to make that much fill light.

 

I must say, that the above link to the HDRI-Wiki page has added a very interesting artistic justification to this idea as well.

[Sam Wells]

Wow this idea of yours is just to deal with contrast in daylight exteriors ?

 

Hi John, after Kodak went with the Vision films I pushed EXR & 74/46 for daylight so I could actually get a real shadow B)

 

-Sam

[Matt Kelly]

What about bi-packed film? Is remjet too opaque to get any exposure on another strip of film behind it?

[Leo Anthony Vale]

What about bi-packed film? Is remjet too opaque to get any exposure on another strip of film behind it?

 

When I was at WRS, someone had a multicamera night shoot with explosions, where a magazine was loaded

emulsion in. The image was many stops underexposed with a heavy red cast.

 

For shooting bi-pack color a camera, in addition to having the gate adjusted to hold two films, had to have the ground glass shifted back to allow for the repositioned film plane & the lens had to have their focus adjusted.

 

Plus the front film acts as a diffuser, so the red neg, the back film, was rather unsharp. One of the reasons for the red halos around flames and lights in 3-strip Technicolor.

[K Borowski]

Do you have any idea how expensive it would be to develop your own film format? At this late date in the game, not only would it be expensive, it'd be a total waste of money.

 

Use a fill card or a reflector. Problem solved! I love throwing money at problems to solve them, don't get me wrong, but you're throwing a million dollars at a $2.50 problem, literally.

[Matt Kelly]

The image was many stops underexposed with a heavy red cast.

 

Ah, so probably a bad idea.... i was thinking the tint could be corrected a bit and the second layer could be used to resolve some of the areas that you would overexpose on the first layer.

[K Borowski]

Ah, so probably a bad idea.... i was thinking the tint could be corrected a bit and the second layer could be used to resolve some of the areas that you would overexpose on the first layer.

 

IIRC, there was a post on here a while back that stated that achieving proper exposure through the base with rem jet coating (nothing can really be done to correct the scattering diffusion) would be an extra 6-7 stops. So a 500T would effectively turn into an 8 ASA stock. This makes this technique utterly impractical except for controlled lighting situations where you can really pump in the lighting.

 

Factor in additional light loss due to beamsplitter (remember too that the original technicolor didn't have remjet because it was B&W film with a anti halo dye specially designed by Kodak with a beamsplitter process in mind) and you're below a 1 speed film. . .

 

Maybe using a fill card might be easier?

[Mike Simpson]

Do you have any idea how expensive it would be to develop your own film format? At this late date in the game, not only would it be expensive, it'd be a total waste of money.

 

Use a fill card or a reflector. Problem solved! I love throwing money at problems to solve them, don't get me wrong, but you're throwing a million dollars at a $2.50 problem, literally.

 

 

 

Ive had his idea for a while as well, but ive been thinking of it less as a problem as much as an interesting new technique. It also doesn't necessarily need to be as grandiose as creating a new format. A beam splitter into two cameras (much like the trick shots in 300), or maybe even trying to improve on the idea behind the genesis and varying the light sensitivity of the sensors on HD cameras would yield useable results.

 

Ill be the first to admit that HDR is generally over the top and pretty awkward feeling, but done well it can have a nice surreal effect, and I could definitely think of uses for a version of HDR in film.

 

And really if that is a look you are going for, HDR is actually fairly easy to apply and (although I dont know enough about post production to say for sure), I imagine if you were after such a look it would be much more efficient, and probably cheaper, than trying to achieve the look in a DI, or thru cgi, etc.

 

Its pretty hard to say something like this would be a total waste of money. I would say something like Transformers is way more of a total waste of money =p

[K Borowski]

Ive had his idea for a while as well, but ive been thinking of it less as a problem as much as an interesting new technique. It also doesn't necessarily need to be as grandiose as creating a new format. A beam splitter into two cameras (much like the trick shots in 300), or maybe even trying to improve on the idea behind the genesis and varying the light sensitivity of the sensors on HD cameras would yield useable results.

 

That is very reasonable, and has, in fact, been done by someone on this forum, using B&W film filtered to get a real vintage 2-strip technicolor look.

 

Its pretty hard to say something like this would be a total waste of money. I would say something like Transformers is way more of a total waste of money =p

 

But now you are lumping in your (reasonable) method in with one that is unproven, unwieldly, and would involve probably at a minimum tens of thousands of dollars worth of development money. I'm not saying beamsplitters are impractical. They are very practical, and have been extensively fieldtested for the many years that 2- and 3-strip technicolor was prevalent, in addition to being used in background projection. I'm saying a new 6-perf film format that must be advanced at least 24 times every second is impractical.

 

And despite the fact that I did not watch or follow the Transformers phenomenon growing up, I liked the film :P