Home of Professional Cinematography since 1996

HD To 35mm – Continued

Published : 19th December 2003


After 2 years working constantly on HD, now I'm going to make my first work on HD to transfer to 35mm film I have a very clear idea of how to do it with the Panasonic 27F, but I am a little confused with the F900.

I know that this must be a very usual question in the list, but I have been checking the archives all day long and I'm not sure yet of how to work, so... apologies if I ask a dumb question.

My question is about the gamma. I know that I have to work with the film mode in the gamma table, but with which one 3? 5? maybe 4? And why?

Thank you!

Pol Turrents
Spanish DP
www.directordefotografia.com



Pol wrote:

>I have a very clear idea of how to do it with the Panasonic 27F, but I am >a little confused with the F900.My question is about the gamma.

This question raises my main objection to Panasonic's marketing of the CineGamma feature on the Varicam. Throw a switch make film transferable HD. Absolute rubbish.

The F900/3 has the ability to create nearly infinite gamma tables with the User Gamma function. If you are not using the /3 or even if you are, get together with the transfer house who is doing the film out and work closely with them. NO switch or menu is going to create the necessary information for all types of film stock neg or print or transfer rigs, i.e. Laser CRT EBR etc.

The best advice is to choose a transfer facility that has a lot of experience in this area. Considering the hundreds of film outs from CineAlta F900 there is A LOT of knowledge out there if you work with the right facility.

I have seen incredible film outs from a DoP in Japan - Sakamoto san who uses the Varicam and developed the CineGamma with the factory but his results were not from a gamma lookup table switch, alone, regardless of the irresponsible marketing blah blah from Panasonic. It would be like Kodak touting a Connie Hall look from their film.

Of course everyone here knows that using a DigiPrime on your camera is THE way to get the best film-out. No seriously work closely with the film-out facility to develop the camera set-up that optimises your "look"

Rant over

Michael Bravin
Chief Technology Officer
Band Pro Film/Digital
www.digiprimes.com



Has anyone out there created any custom gamma functions that work really well for holding down burn-out in the highlights and prevent crushing in the shadows, so you get a nice, flat image that works well in post color correction?

I'm going to be shooting a short film next February, and right now I'm not really sure which or what format to shoot with. Here's the list I've come up with so far, and I'm trying to keep the budget at approx. $2000. It'll be a one day shoot, and will end up being projected digitally using a DLP projector (not on 35mm).

Viper with CineRAM - Depends on how much the CineRAM rental rates are and if it comes out in time. Right now with the Director's friend and S.Two products, the cost is way too high since those boxes cost just as much as the Viper to rent.

Super16 with DI process (7218) - I figure I could get the whole thing in the can with no more than 2400ft., then have the film transferred to full res Cineon or DPX files from either a film scanner or I could get the transfer house to give me the full res DPX files from the Spirit Datacine. I figure I could keep the costs down by doing the whole movie digitally (since it won't be more than seven minutes long), and do all the color correction myself with the DPX files when I'm done with the rough cut. I'd then do a digital "negative cut" with the DPX files, and assemble together a hi-res QuickTime file that would then be pumped through the DLP projector.

Sony F900 - I think this might be the cheapest route for me to take, but I'm worried that anything that blows out will have a really electronic look to it rather than a nice film-like blowout, and basically give away the fact that it originated on video (even if it's high-def). From the samples I've seen on the CML site that Geoff shot with the Viper, I can see that the highlight burnout is very smooth, and it has an awful lot of headroom to work with. The /3 upgrade adds about a stop of headroom, but I'm wondering if that's at the sacrifice of the shadows - in other words, the camera is basically automatically underexposing itself by one stop, but it looks like it's exposed properly because of the way Sony's done the electronics. If this is the case, then you probably loose a stop in the shadows.

Anyways, my point being that is there a way in the User Gamma function to create a gamma table that will allow you to sculpt any highlights that might occur (some of the material is going to be shot in a documentary style, so there won't be a lot of lighting control, i.e. bright skies and windows), but not crush the blacks, and give me a look that does not give away it's electronic origination? Another thing I'm worried about is the results of color correction on the HDCAM material.

Since it's 3:1:1, will it hold up to color correction enough before it falls apart, unlike the 4:4:4 RGB formats from the Viper and Super16 which seem to have a lot of room to mess with?

Jason Rodriguez



I think you're a little confused as to the Viper with CineRAM scenario, this will never be cheaper than a DF or a S2 alone as you'll need something to store the material that you shoot with CineRAM.

In other words you'll need the CineRAM AND a DF or S2.

Before anyone shots me down, yes there are/will be other ways but show them to me now on a hireable basis!

At $2,000 I don't think you have any route other than F900 or the Panasonic.

Cheers

Geoff Boyle FBKS
Director of Photography
EU Based
www.cinematography.net



Geoff Boyle wrote:

> In other words you'll need the CineRAM AND a DF or S2.

Actually, the new version of CineRAM can be used to download right into a laptop or other computer. Noel has come up with some very clever things using either Firewire or Gig Ethernet, I think.

I have a feeling Jason has lots and lots of computers.

Jeff Kreines



I was thinking of using the gigabit Ethernet ports on the back of the CineRAM to download the DPX files to a firewire hard drive via laptop. And hard drives are getting relatively cheap now, at lest than $1 per Gigabyte. For instance, I know a place here where I can get a 250GB hard drive that will store 21 minutes of viper output for $184.

According to BayTech's CineRAM pdf, a firewire 800 drive should be able to download an entire CineRAM cartridge in 13 minutes, and you can download from it while you're shooting to extend the time before it fills up (and once it fills up, then you have to wait around 13 minutes, not bad, since we can do this while setting up the next shot).

So while the Viper/CineRAM might be little more expensive than the F900, I think by using off-the-shelf hard drives for storage via Firewire 800 and a laptop I can get around the costs for an S.Two or DF. But again, the question comes down to how much CineRAM will rent for, and when they'll be available. I'd gladly go with the F900, but I'm really worried about an electronic look to the highlights, since I know there will be times that we'll have overexposed blown-out areas, and I really don't want to have ugly highlights that scream "Video!" I don't mind blowout, I just can't stand oversharpened, detail enhanced, crazy collared, non-smooth transitions (especially in color transitions) into the highlights that I see on many video cameras, and even some F900 footage (although this was before the /3 upgrade).

Jason Rodriguez
Post Production Artist
Virginia Beach, VA



Jeff Kreines writes :

>Actually, the new version of CineRAM can be used to download right >into a laptop or other computer.

I didn't think that was an option, yet.

I hope that I'm wrong

In fact I'd like to know very soon as I have a shoot in February

Cheers

Geoff Boyle FBKS
Director of Photography
EU Based



Jason Rodriguez writes :

>I was thinking of using the gigabit Ethernet ports on the back of the >CineRAM to download the DPX files to a firewire hard drive via laptop.

If this route is actually available when you want to shoot then I'd certainly go for it.

The pictures out of the Viper are significantly better than the Sony/Panasonic cameras and are really tweakable in post.

I hope that Bill Lovell is reading this thread.

Just in case it's not part of his business plan, I wonder if Noel wants a European test of CineRAM in February

Cheers

Geoff Boyle FBKS
Director of Photography
EU Based



>My question is about the gamma. I know that I have to work with the film >mode in the gamma table, but with which one 3? 5? maybe 4? and >why?

Gamma Table 5 is most commonly used. Table 3 is a bit contrasty. Table 4, I seem to recall, is not too different from 5.

And once thou reachest Gamma Table 5, thou shalt lob it at thy enemy, who, being naughty in My sight, shall snuff it. Amen.

Sorry, that just popped into my head. Need to get some sleep...

David Mullen
Cinematographer / L.A.



Geoff Boyle writes :

>Just in case it's not part of his business plan, I wonder if Noel wants a >European test of CineRAM in February

That would be great!

Noel Sterrett
Baytech Cinema
www.baytechcinema.com



Jeff Kreines writes :

>Actually, the new version of CineRAM can be used to download right >into a laptop or other computer.

Not so. I'll have the latest CineRam on a Viper at my HD seminar at next month's DV Expo. Currently you still need a CineWave, AJA or some other card to "unload" the data. Quite soon, (pre-NAB) the production run should have reached the US (RAM needs to be Shipped rather than flown due to cosmic radiation) and will use a very fast Ethernet (ie: GigaNet) type system.

Scott Billups - LA



>Not so. I'll have the latest CineRam on a Viper at my HD seminar at next >month's DV Expo

I thought the CineRAM isn't shipping yet. At least that's what I was told by Plus8Digital when I inquired two weeks ago.

The product on the website advertises dual gigabit Ethernet and there's even a press release regarding this fact that came out at IBC. And hasn't Noel said on this list that barring any parts delay they should have a shipping product by January (with Gigabit Ethernet)?

Jason Rodriguez



>Not so. I'll have the latest CineRam...

Just to clarify, the "latest" CineRAM is the original prototype, which does not have GigE. To use it, you need an HD-SDI recorder to unload data. This is the unit we have been using for demonstrations and tests, but was never planned as a production unit.

For the production version, which is currently being manufactured, we have added dual gigabit Ethernet (GigE). With the production version, data can be downloaded like the prototype to an HD-SDI recorder, or to a general purpose computer (including laptops) using GigE.

We expect to have the production version available (at least for testing) in January. However, the new IBM processor we are using is currently in short supply so there are no guarantees. I have, however, sent a long letter to Santa.

Noel Sterrett
Baytech Cinema



BTW,

Kudos Noel for implementing GigaE on the CineRAM for use with general use computers such as Laptops, etc. This, IMHO basically takes Digital Cinematography to the next step like Digital photography was able to do with CF cards that could be quickly downloaded to laptops (instead of tethered digital backs and SCSI set-ups).

At least for me, and I'm sure many others, getting beyond the bounds of HD-SDI and the pricey hardware it requires (not to mention RAID arrays for recording those sustained transfer rates) is a huge boon-at least for on set and on location. So whoever thought of GigaE, web interfaces, embedded Linux, etc., I say a big thank you!

Now hopefully it won't cost as much as a Director's Friend to rent

Jason Rodriguez
Post Production Artist
Virginia Beach, VA



>Quite soon, (pre-NAB) the production run should have reached the US >(RAM needs to be Shipped rather than flown due to cosmic radiation) ....

We all know that CCDs are susceptible to airborne radiation, but RAM?

I asked a friend who has been designing high-end digital video gear for 20+ years about this.

He responded :

Just for interest I have looked further into this cosmic radiation problem. There is a potential problem with "soft errors", which means that the DRAM reads out the wrong state when working. However, IBM detect this at around 1 bit error per month, when using a 256Mbit RAM continuously at full speed, which is pretty small (way, way less than the error rate expected off disk).
This sort of effect is well known, but so small as can be ignored for nearly all practical purposes (and certainly all purposes that we deal with).

I can find no mention of cosmic radiation introducing a "hard error", that is one which permanently affects device operation.

If this were really a problem, you couldn't ship a CineRAM by airplane! (The aluminium case is essentially transparent to radiation.) That would not be a good thing.

Jeff "a big slab of irradiated beef" Kreines



>Has anyone out there created any custom gamma functions that work >really well for holding down burn-out in the highlights and prevent >crushing in the shadows...?

I think Kodak and Fuji, among others, have worked on this...

Sorry,

Adam Wilt / Video Geek / Menlo Park CA USA



Just some thoughts about the Gb interface possibilities with CineRAM. We transfer huge amounts of data here regularly on a Gb Enet network and via 1394 drives, we are getting useful transfers on and off of a singe firewire 800 drive of 38Mbs and 45Mbs on striped drive pairs using Apples Drive utility, which is slower than I would hope. 33mbs on firewire 400. in this case the drives are the limiting factor rather than the interface.

Using G5 to G5 both with Xserve raid attached, via a Cisco switch (I don’t have a suitable engineering tool to measure the actual network bandwidth) but transfers of 5.5Gb per minute can be achieved with out Jumbo frames being enabled. I would hope for faster but as yet haven’t achieved better results as yet.

Has anyone any figures for an increase for data transfer rates with Jumbo frames being enabled on Gb Enet ?

Dave Blackham
UK Consultant



>DBHas anyone any figures for an increase for data transfer rates with >Jumbo frames being enabled on Gb Enet ?

Jumbo frames can be tricky since they are not universally supported among GigE switch manufacturers. For CineRAM, we are using a new IBM processor which includes a TCP Hardware Accelerator.

The accelerator should help offload the GigE packet fragmentation overhead from the processor and allow for improved performance, even without jumbo frames. For point-to-point (e.g., CineRAM to G5), we will be benchmarking the difference with jumbo frames and will let you know what we find.

Noel Sterrett
Baytech Cinema