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2k scan or HD telecine for 4-perf 5219?


Dylan Lewis

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Hi all,

 

I've recently finished shooting a music video on 4-perf 35mm, 5219. I'm about to send the film off for processing/transfer and I'm sort of stuck as to whether I should get an HD telecine or a 2k scan. The price difference given the amount of film I'm working with is not that large of a concern. My lab of choice (the wonderful Video and Film Solutions in Maryland) uses a Spirit for both.

 

Now obviously, as it's a music video, it'll only ever be viewed on computer screens, so I'm sure the difference won't be too drastic between the two, but there are still some factors to consider. First off, a solid amount of the video is shot in a city (Richmond, VA) at night, with only available light, meaning I was basically consistently rating the film at around 2000 ASA, sometimes higher. So grain will definitely be an issue, and on top of that, I plan on pushing a few of the rolls 1 stop. From my previous experience with 2k scans, it seems as if the higher resolution relative to HD makes grain seem even more apparent in scans than it does in telecine, so would the combination of the thin negative, the push, and the 2k scan make the grain way too intense? I understand that "way too intense" is a vague quantifier, so I guess to put it a bit better, would I be better off in terms of keeping the grain at a manageable level (given the negative that I'll be working with) with an HD telecine or a 2k scan? And I guess in a more general sense, what would be the advantages (or disadvantages) of going with 2k in this situation?

 

Also, this may be a stupid question, but just to clarify my understanding, it's definitely possible to maintain the 1:33 aspect ratio with an HD telecine, right? Any time I've previously had HD telecine of 35mm it's been automatically cropped by the lab to conform to a 1920x1080 frame. But theoretically wouldn't it be possible to maintain the full 4-perf frame with no cropping if I specifically instructed the lab and just have bars on the left and right of the frame? The film was framed for and always intended to be presented in that format.

 

Any help is greatly appreciated!

 

Thanks,

Dylan

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I agree that you should get a 2K scan and that Video Film Solutions in Maryland is fantastic.... But....

 

If you are truly concerned with dynamic range, properly resolved grain without added noise in your blacks, etc... I would send your film for an HDR 2K scan at MetroPost in NYC. They have a LaserGraphics Director which uses a full frame monochrome sensor. If you request a full HDR transfer each frame will be scanned 9 times! That is, it will get 3 separate intensity/exposure scans in red, blue and green.

 

Sprit Datacine's are great machines and I love the results. But, if you truly want all the information off your film and a true "film like" image, I would go with MetroPost.

 

If you're closer to Boston, Cinelab also has an HDR monochrome home-built system. Technically, it should be at least as good if not better. It's called a Xena. But, I have no direct experience with using the HDR functionality there.

 

Here is a 16mm film clip done by MetroPost. There is no noise reduction, just color/light grading. (There are some Super 8 parts... not done by MetroPost).

 

 

I have sent this film to many different scanning houses and I have yet to see one come close to getting this same result. All the others are noisy or have clipped highlights or muddied shadows. This came out just as I'd hoped.

 

Dave

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Oh, as for the 2K vs HD part... Definitely go 2K...

 

You say the grain is "more apparent" with your 2K scans. This is probably true because it will be better "resolved". This also makes it easier to remove with noise reduction software since it's sharper and more specific. If you look closely at an HD vs 2K scan of the same 35mm footage, you should notice that the grain isn't gone... just aliased and muddied so it almost blends in with an out-of-focus background. But, make your in focus images look muddied or less sharp.

 

I shoot mostly Super 8 and I still find a 2K scan worthwhile because of how perfectly resolved the grain ends up being. It makes it easier to remove in post and leads to a sharper looking overall image because the muddied grain isn't distracting from the image. There isn't enough "resolution" on Super 8 for 2K, but the increased grain makes it's even more important to resolve said grain.

 

You should see pretty much the same results via either HD or 2K from the Spirit at Video Film Solutions, other than the grain discussion above. They literally use the same 2K Datacine equipment... just one setup outputs to HD and the other to 2K DPX/Prores, etc. So, the machine and "quality" should be the same.

 

Dave

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Sorry... another post... lastly note on the 4x3 frame...

 

Yes, if you request "pillar boxing" they should deliver a 1920x1080 frame with pillars on the sides.

 

If you request a 4x3 2K frame, you will actually get even more (above and beyond) a 16x9 2K. You will get an actual 4x3 DPX or Prores file with a 2048x1556 image area rather than a wide screen 2K which is 2048x1240. A correctly framed 2K 4x3 will give you 1556 of image hight resolution top to bottom compared to only 1240 if it's 16x9 pillar boxed 2K and compared to 1080 hight resolution of pillar box HD 16x9. I'm not sure why no one can seem to do the same thing with HD 1920x1080 scans... <shrug>

 

Dave

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I've always been a huge fan of doing true 2k on the scanity at cinelicious even if its for music videos. But, if its seriously affecting your budget, I'd suggest doing a telecine so you can spend more time on getting the color right. On the web, it can be VERY difficult to tell the difference. As much as I would love to tell myself otherwise...

 

2k scans:

 

HD Telecine on a Spirit:

(this was underexposed two stops on 5219 so will give you a great idea grain wise where you're at)
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Thanks guys for all of your responses! David, I've heard great things about the Lasergraphics Director, I'll have to ask Metro Post for a quote. And you've definitely made a strong case for 2k in terms of grain resolution.

 

Also, Evan - it's cool that you commented on this post, I really dig your work and that Nightlife video was actually the video that gave me the confidence to really push into the realms of underexposure with 5219, so thanks, it's a beautiful piece of work. Was that shot with only existing/available light? I'm a bit nervous that I may have pushed a bit too far into the dark, Richmond's not exactly a brightly lit city and my light meter was pretty much consistently giving off a 1.8 (even rated as high as 3000 occasionally), but my lens (didn't have the budget to rent!) is a rehoused still photography lens that only opens up to f/2, so I'm basically just losing sleep until I can get the film processed. But it's good to know that even with 2 stops underexposure, a Spirit telecine can yield results that beautiful.

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Thanks guys for all of your responses! David, I've heard great things about the Lasergraphics Director, I'll have to ask Metro Post for a quote. And you've definitely made a strong case for 2k in terms of grain resolution.

 

 

Tell Jack Rizzo that Dave Cunningham of New England Vintage Films sent you!

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Thanks guys for all of your responses! David, I've heard great things about the Lasergraphics Director, I'll have to ask Metro Post for a quote. And you've definitely made a strong case for 2k in terms of grain resolution.

 

Also, Evan - it's cool that you commented on this post, I really dig your work and that Nightlife video was actually the video that gave me the confidence to really push into the realms of underexposure with 5219, so thanks, it's a beautiful piece of work. Was that shot with only existing/available light? I'm a bit nervous that I may have pushed a bit too far into the dark, Richmond's not exactly a brightly lit city and my light meter was pretty much consistently giving off a 1.8 (even rated as high as 3000 occasionally), but my lens (didn't have the budget to rent!) is a rehoused still photography lens that only opens up to f/2, so I'm basically just losing sleep until I can get the film processed. But it's good to know that even with 2 stops underexposure, a Spirit telecine can yield results that beautiful.

Thanks Dylan!!

 

I shot wide open on master primes and my meter read between .35 and .7 for most of the night work. I had a small litepanels LED i used to add direction to the light but it really wasn't adding much exposure.

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When I had my 16mm negative scanned to HD tape, a 2K Spirit Datacine was used and it turned out beautifully. So when talking about HD telecine & 2K scans, isn't the process pretty much the same?...

I'm wondering if a 2K scan results in a file of uncompressed individual frames? As opposed to a Telecine which outputs a standard video file.

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The 2K scan scans each film frame as an individual DPX file which forms an image sequence. Each frame (for 2K) is around 12 MB, so it adds up... The amount of information captured and stored in a 2K scan vs. an HD telecine is massive. It's not just the resolution that's to be considered, but the bit depth and video compression (or lack thereof in the the 2K scan).

 

I'm actually in a similar boat for a feature film. I just sent tests out to a couple of labs on the east coast and had the film both scanned and telecined. The difference between the 2K scan and the telecine is certainly apparent, even after the 2K image sequence is compressed to the same format as the HD (in this case, ProRes).

 

Although, I haven't uploaded anything and considered online compression. At that point, I'm wondering how obvious it would be...

 

Personally, this is the first time I've worked with 2K DPX files (I've always had film telecined to HD, and have been pretty comfortable sticking with HD ProRes), and I'm already a little overwhelmed. I'd certainly much rather go for the quality of a 2K scan, especially with considerations of projecting the project eventually. Although, I'm taking into account the massive storage that would be required for storing and backing up all the footage for a feature. Plus, the additional cost of the scan itself, of course. On a low budget, I would be a bit more comfortable sticking with HD and then having the finished edit scanned from an EDL, if things are looking promising. Although, I don't know what the additional costs at that point would be...

 

Also as was pointed out, I do like the ability to reframe within the full 4-perf frame that the 2K scan offers.

Edited by John Jaquish
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It's not just the resolution that's to be considered, but the bit depth and video compression (or lack thereof in the the 2K scan).

 

This is absolutely correct, but Anthony's question was about resolution. So if you assume an HD transfer was pillarboxed rather than 1.78:1, the actual image area is somewhere around 1440x1080ish (1.55 Million pixels). If you transfer that same film to 2k at 2048x1556, it's over 3.1 Million pixels. Even if the film was shot with the intention of cropping for 1.78:1, the 2k scan gives you greater flexibility to reframe shots in post, rather than baking those decisions in when doing the transfer.

 

In terms of your own scans, you have a few options: you can request the scan be done to a format like ProRes 4444 (which is definitely easier to work with for most people, and in many cases is good enough as the final format). Alternatively, you could make 2k Prores files from the DPX sequence in any of a number of applications. This becomes a proxy for the DPX scans. So you can edit, reframe, etc in your NLE, and then do your final grade and conform the DPX files at a facility that's set up to handle it more easily than one can do on a desktop machine. If you want to work with DPX directly, you need a RAID capable of moving about 500MB/second, a fairly substantial GPU, lots of RAM, and an edit/grading system that can work with the files directly.

 

For most people, working with proxies makes more sense and is more convenient. And with modest hardware, you can do this at 2k, in a format like ProRes, without needing a high end RAID.

 

-perry

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The 2K scan scans each film frame as an individual DPX file which forms an image sequence. Each frame (for 2K) is around 12 MB, so it adds up... The amount of information captured and stored in a 2K scan vs. an HD telecine is massive. It's not just the resolution that's to be considered, but the bit depth and video compression (or lack thereof in the the 2K scan).

 

I'm actually in a similar boat for a feature film. I just sent tests out to a couple of labs on the east coast and had the film both scanned and telecined. The difference between the 2K scan and the telecine is certainly apparent, even after the 2K image sequence is compressed to the same format as the HD (in this case, ProRes)

 

Ok so it is an image sequence, which does make a lot more sense than just a subtle increase in resolution.

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Ok so it is an image sequence, which does make a lot more sense than just a subtle increase in resolution.

 

Although 2K does start off as an image sequence, it can be directly output to Prores or other video file formats.

 

Similarly, systems like the ScanStation or 2K Spirit Datacine can output HD (1920x1080) to DPX/image sequences. This is not as common however.

 

In either case (Scantation or Spirit 2K), they are functioning as a scanner which scans each frame and then outputs it to a format. That format can be an image sequence or a video file.

 

Telecine is different. Telecine is a live video feed of a certain format. For example, a Spirit HD Telecine will output in a video stream which would then need to be converted to DPX, not the other way around. They were designed and intended for output to a video file, not an image sequence.

 

So, again, although 2K is normally done as image sequences, it can be done output directly to a video file if you want... just generally not directly to tape like a telecine can do.

 

But, HD CAN me the same way. Again, it just usually isn't.

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Yeah I've only recently started hearing mumbling about the newer scanners doing 2K and image sequence files but wasn't sure if they were related. I've been working with image sequence but on a smaller scale (JPEG) a lot this past year. They work great in my NLE (Sony Vegas 10) for frame by frame editing and run smooth. Except with Sony Vegas I have to manually disable the auto frame blending default with each import to avoid defeating the purpose of true frame by frame editing. I wonder if FCP has the same issue with image sequence files?

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FCP - at least version 7, can't speak to X, since I've never used it - doesn't really play well with DPX sequences. But again, make a proxy format like ProRes or Avid DNxHD and work with that, then conform later in Resolve or some other application that handles DPX natively. GlueTools lets you open DPX in FCP 7, but we had mixed results with that in testing and found that it was just easier to work in ProRes proxies for editing.

 

Most scanners can also transfer to TIFF sequences as well, which is a bit more generic than DPX and may work better in your NLE. You'll likely still have the system performance issues you'd have with DPX, though - lots of overhead with any HD or higher resolution image sequence.

 

-perry

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This is absolutely correct, but Anthony's question was about resolution. So if you assume an HD transfer was pillarboxed rather than 1.78:1, the actual image area is somewhere around 1440x1080ish (1.55 Million pixels). If you transfer that same film to 2k at 2048x1556, it's over 3.1 Million pixels. Even if the film was shot with the intention of cropping for 1.78:1, the 2k scan gives you greater flexibility to reframe shots in post, rather than baking those decisions in when doing the transfer.

 

In terms of your own scans, you have a few options: you can request the scan be done to a format like ProRes 4444 (which is definitely easier to work with for most people, and in many cases is good enough as the final format). Alternatively, you could make 2k Prores files from the DPX sequence in any of a number of applications. This becomes a proxy for the DPX scans. So you can edit, reframe, etc in your NLE, and then do your final grade and conform the DPX files at a facility that's set up to handle it more easily than one can do on a desktop machine. If you want to work with DPX directly, you need a RAID capable of moving about 500MB/second, a fairly substantial GPU, lots of RAM, and an edit/grading system that can work with the files directly.

 

For most people, working with proxies makes more sense and is more convenient. And with modest hardware, you can do this at 2k, in a format like ProRes, without needing a high end RAID.

 

-perry

That's true -- I forgot the original question was regarding 4:3, for which 2K would certainly provide better resolution options.

 

And thanks for your thoughts for my project. I'll probably be going the Prores proxy route, then, like you said, going somewhere to conform and grade the DPX.

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FCP - at least version 7, can't speak to X, since I've never used it - doesn't really play well with DPX sequences. But again, make a proxy format like ProRes or Avid DNxHD and work with that, then conform later in Resolve or some other application that handles DPX natively. GlueTools lets you open DPX in FCP 7, but we had mixed results with that in testing and found that it was just easier to work in ProRes proxies for editing.

 

Most scanners can also transfer to TIFF sequences as well, which is a bit more generic than DPX and may work better in your NLE. You'll likely still have the system performance issues you'd have with DPX, though - lots of overhead with any HD or higher resolution image sequence.

 

-perry

I think the performance of newer desktops have a lot of potential in handling image sequence files. What PC specs did you try with the DPX files? Do you think it was the PC or FCP that was struggling? I'm trying to think comparatively with my PC and software ability which is nearing 4 years old now. Intel i5 650 3.2ghz, 16GB ram, 1 TB RAID array, and Sony Vegas 10. I've been working with smaller scale image sequence files, uncompressed jpegs which have been very user friendly. I can export a TIF sequence but haven't tried yet. i will next week and see if i test my systems limits. But the new Intel i7 and AMD generations are pretty far out and hold up to 64GB ram. So my point is if someone was putting together a new desktop edit suite, it may not be too hard to put together something affordable that can handle uncompressed DPX files very well. Because editing and processing image sequence files have so many advantages. It comes with a lot of the same feel as splicing analog frames with the accuracy and crispness like reel to reel. The crisp full frames are also so key when color correcting and sweetening all of your image detail from a raw negative. Then you have a lot more freedom when outputting to a video file, or even multiple file types for different uses... while maintaining the best chain of quality.

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I think the performance of newer desktops have a lot of potential in handling image sequence files.

 

[...]

 

I'm trying to think comparatively with my PC and software ability which is nearing 4 years old now. Intel i5 650 3.2ghz, 16GB ram, 1 TB RAID array, and Sony Vegas 10. I've been working with smaller scale image sequence files, uncompressed jpegs which have been very user friendly. I can export a TIF sequence but haven't tried yet. i will next week and see if i test my systems limits. But the new Intel i7 and AMD generations are pretty far out and hold up to 64GB ram. So my point is if someone was putting together a new desktop edit suite, it may not be too hard to put together something affordable that can handle uncompressed DPX files very well.

 

 

It's not the performance of the desktop machine (CPU/GPU) that's really at issue - it's more of an I/O thing. 2k DPX files are about 12MB/Frame. Unlike a quicktime file (a single stream of data with less disk overhead), with DPX or TIFF every single frame has to be opened, displayed, closed. That's a lot of hits to the drive, all happening very quickly, with a lot of operating system resources spent on transactional data (find the file/open the file/display the frame/close the file -- for every frame).

 

It doesn't matter how fast your computer is, you're going to need a disk subsystem that's capable of moving about 500MB/second. SSDs can do it, but they're too small to be useful with DPX - you need terabytes of extremely fast storage for files like this. At minimum, you would want a 6-drive RAID, but 8 would probably be faster and more reliable, especially with SATA drives, which tend to slow down quite a bit as they fill up. More drives in the RAID means the load is spread out more, which means you can push them farther.

 

Our first MTI Correct restoration system was a circa-2004 Dell PC - a dual processor Xeon PC running Windows XP. High end at the time, but a slug by today's standards. It easily (and only) handled DPX files. ...But only if they were on a SCSI RAID that could move about 550MB/second -- and on top of that, MTI used a proprietary filesystem where all the files lived inside a single disk image file on the RAID, so even though the RAID itself was formatted as NTFS, the actual DPX files lived inside the one file that was on that RAID, which appeared to the MTI software as a drive with its own highly efficient file system. In that way they were able to work around the issues of desktop filesystems like NTFS, to push the data through without dropping frames.

 

In contrast, you can play a 2k ProRes 4444 file off of a single internal SATA drive (no RAID), on a relatively modest computer, without hiccups.

 

 

Do you think it was the PC or FCP that was struggling?

 

With the FCP testing we did, it wasn't a matter of struggling to keep up - with fast enough disks you should be able to make it work. But FCP was never built to handle DPX, and so it was buggy and clunky. You have to install a third party plugin (like GlueTools) to get DPX to import and it was just unreliable and flaky. It would play back ok, but it we had lots of other weird issues with files disappearing, hanging, etc. Also, certain plugins didn't work correctly, if I recall. This was several years ago, but I doubt it has improved too much since then. FCP 7 just isn't meant to handle the format.

 

Because editing and processing image sequence files have so many advantages.

 

Absolutely - and that's why you should look at software that was designed to deal with image sequences from the get-go. Like Resolve (which now has more editing capabilities built-in, too). And it's free. So if you're building a PC from the ground up, I'd build it with those specs in mind. Either way, though, you're going to need massive and very fast storage for 2k or larger image sequences.

 

-perry

Edited by Perry Paolantonio
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I would say that 80% of the data scans we do at Cinelab get converted to ProRes444 either as a flat pass or as a graded output, 2K DPX is allot of data but it is easier to deal with now on Mac and PC machines with reasonably fast disk array subsystems and fast GPUs. 4K DPX is another story and needs a massively fast array and multiple GPUs with lots of VRAM like the Titan. We can and have made 16bit TIFFs for clients and they can be even more disk intensive because they are bigger for the frame size 10bit LOG vs 16bit Lin.

 

Beyond color space advantages of 2K Data scanning over HD is that most data scanners oversample the scan resolution i.e. our Monochrome area sensor in our Pin Registered Xena scans S16mm at 3.5K to make 2K output. Our new fast machine has a 3.4K Color sensor for 2K output. Most older Telecine systems do not oversample and the original SDC-2000 Spirit has a 1920 pixel B&W sensor and three 960 pixel color arrays, it can make "2K" DPX but is in fact physically 4:2:2 and undersampled.

 

-Rob-

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It doesn't matter how fast your computer is, you're going to need a disk subsystem that's capable of moving about 500MB/second. SSDs can do it, but they're too small to be useful with DPX - you need terabytes of extremely fast storage for files like this. At minimum, you would want a 6-drive RAID, but 8 would probably be faster and more reliable, especially with SATA drives, which tend to slow down quite a bit as they fill up. More drives in the RAID means the load is spread out more, which means you can push them farther.

 

Our first MTI Correct restoration system was a circa-2004 Dell PC - a dual processor Xeon PC running Windows XP. High end at the time, but a slug by today's standards. It easily (and only) handled DPX files. ...But only if they were on a SCSI RAID that could move about 550MB/second -- and on top of that, MTI used a proprietary filesystem where all the files lived inside a single disk image file on the RAID, so even though the RAID itself was formatted as NTFS, the actual DPX files lived inside the one file that was on that RAID, which appeared to the MTI software as a drive with its own highly efficient file system. In that way they were able to work around the issues of desktop filesystems like NTFS, to push the data through without dropping frames.

Perry,

 

I'm thinking of building my own scanning system and I wanted to ask a bit further about the info you put here. A colleague has specced the desktop components for me and as part of this he has set out two 250 G SSDs to handle all the operations and then two 1.5 T disc drives arranged as RAID to be fed by the SSDs along with one video card (GPU in the system). I am hoping this can work with 2K DPX and even 4K DPX. I put your comments about moving 500 MB/sec to him and he said the 2XSSD/2X1.5T Disc RAID arrangement will handle that, are you saying a larger RAID array is needed?

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