Stock choice for HD to 35mm transfer?

[Adam Paul]

I see that normally transfer houses offer the option of either intermediate stock or camera negative when transferring HD to 35mm film.

What are the advantages of one over the other and would types of stock in general (fast, slow etc) impact the quality or look of the transfer as it would if it was originally shot on the stock with a 35mm camera?

[David Mullen ASC]

Most laser recorder transfers are made to color intermediate stock, and most CRT recorders use camera negative stock, generally something slow and fine-grained (Kodak 50D or 250D, or Fuji 64D, etc.)

 

The laser recorder transfer using intermediate stock would impart less of a "look", in other words, be a more faithful transfer of the digital file to film -- it would look a little sharper, finer-grained, cleaner. The camera negative stock would impart more of the look of the camera negative stock (grain mainly, some contrast, some softening.) Some people like that about CRT transfers, otherw would rather retain more out of the HD image.

[Adam Paul]

I was looking at a CRT transfer. I would like to go for the stock that would give me the sharpest image since it's just 720p.

 

By what you said, camera negative would add more of a film look while intermediate would look closer to a straight digital projection?

[David Mullen ASC]

I was looking at a CRT transfer. I would like to go for the stock that would give me the sharpest image since it's just 720p.

 

By what you said, camera negative would add more of a film look while intermediate would look closer to a straight digital projection?

 

Not as dramatic as that. The laser recorder transfer to intermediate would be a little sharper and less grainy -- more "digital" maybe in some people's eyes, while others feel that once you make a print from the intermediate neg and project it, there's plenty of "film look" and grain added by that point, plus HD is already softer than 35mm, so why not try and squeeze as much detail out of the original as possible?

 

Anyway, this is one reason why CRT transfers are becoming less and less common (except for IMAX/65mm work, since there are no 65mm laser recorders.)

 

A CRT transfer to 35mm may impart a stronger "film look" (i.e. hide the look of the original more) by virtue of being slightly softer and grainier.

[Adam Paul]

So for a CRT (Celco) transfer of 720p material, would you recommend intermediate or camera negative for the best quality and sharpness?

And what stock?

Thanks.

[David Mullen ASC]

So for a CRT (Celco) transfer of 720p material, would you recommend intermediate or camera negative for the best quality and sharpness?

And what stock?

Thanks.

 

I didn't know CRT recorders were now using intermediate stock. If a company claims they can do either, have them transfer a 30 sec. clip to either and project the results for you.

[Adam Paul]

That will be hard as they are not local to me.

In any case, theoretically and or technically, what would you recommend?

[David Mullen ASC]

That will be hard as they are not local to me.

In any case, theoretically and or technically, what would you recommend?

 

I really can't say since I've never seen a CRT transfer to intermediate stock -- maybe it would do something odd for all I know. I've only seen laser recorder transfers to intermediate stock and CRT transfers to camera negative stock, and which you'd pick is partly a matter of taste, but I tend to prefer the laser recorder to the intermediate stock because it seems to look sharper.

 

Surely the engineer at this facility that does both has run tests and can tell you the difference in look.

[Dominic Case]

CRT recorders have far less light output than lasers so normally they need to use camera negative stock. This presents a few challenges: one is the graininess, another is the fact that because the gamma of camera neg stock is so low, the brightness range on the CRT has to be pushed to the limits - and the limits are determined by the flare on the CRT, and the spot size. Brighter spot, more speed, more flare, bigger spot, lower resolution: dimmer spot, less speed, reduced flare, smaller spot, more resolution - but slower exposure times per frame. It's usually a trade-off between resolution, speed, and image contrast.

 

Some CRT's are pumped hard to shoot onto intermediate stock in order to get the contrast up to where it should be: some of that is achieved by clever design, but it's always pushing at the limits of resolution, and typically the running speed of the machine with intermediate stock is slower than the same machine set up for camera negative.

 

It's probably more accurate to say that intermediate stock is designednot to add any characteristics to the image, so the results you get on a well-calibrated laser recorder should be pretty close to what you saw on the monitor or digital projection screen during your final grade - rather than saying it looks "more digital".

 

But if the lab is offering you the choice, they should be able to provide you with the pros and cosn of either approach.

 

Me, I'd shoot onto intermediate stock every time: it's designed for that purpose, whereas camera negative stocks are designed for recording full-spectrum real life.

[Adam Paul]

Thanks guys. I will ask them then.