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Is it true 4k scan does not do much for 16mm compared to 2K scan?


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I had read this and wondered if it is true. Not a lot of advantage to 4K over 2K for 16mm. 

"2K, 4K, etc is mainly measurement of width, not height. So adding extra width to the current 2K 4:3 capture frame doesn't really increase the overall quality of the resolution unless your target frame is also 16:9.  To put this in context, 8mm, Super 8 and regular 16mm are all 4:3 aspect ratios. So, as it stands, if you capture in 2K using the entire 4:3 sensor of the current 2K camera, the only way you could see all that information at that 2K resolution is if you float that 4:3 2K image in a 3K or 4K 16:9 frame since there isn't really an industry standard for editing and releasing 2K as 4:3. To prove this to yourself, open up a 4K 16:9 frame in Photoshop and then create insert a 4:3 image that will reach from top to bottom of that 4K 16:9 fram. Then measure the 4:3 image area left to right and you will find that it is pretty close to 2K across. Therefore, if your desire is to output a 4K 16:9 final, the 4:3 image in the middle of that 4K 16:9 frame would, for all practical purposes, still be only 2K in resolution. You can do that now with the current 2K camera. However, if your desire is to fill a 16:9 4K frame then you would have to give up detail at the top or bottom of your 4:3 target frame of film."

I was thinking 4K would give double the resolution over 2K.

...what say you?

Edited by Daniel D. Teoli Jr.
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The MTF curve takes into consideration the resolving power of the camera lens, the filmstock and also the scanner.

As a comparison, at the frequency of 20lp/mm, on 1K you will have 30% modulation response, on 2K 57% and on 4K 63%.

It is a matter of diminishing returns, there is a very noticeable improvement from 1K to 2K, from 2K to 4K it is much less.

These measurements were done on 35mm camera negative, 16mm will be more limited of course.

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It's all about MTF and how crisp your negative is. 

What I've seen is that really good pin registered scanners can get a bit more out of a crisp negative at 4k than at 2k, but only a tiny bit. You do get more noise in the image however and the noise is crisper, so that's something to think about.

Whenever we get our Scan Station, I will do an A/B comparison. 

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I've had some test stuff scanned at 4k before just to see. When using Ultra16 lenses it looks theres definitely a benefit over 2k, but I really dont think you'll get to actual 4k between the lenses and the film stock. If you were finishing a film its probably worth a 4k scan if budget permits, otherwise ya may as well just scan at 2k and upscale.

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22 hours ago, Tyler Purcell said:

It's all about MTF and how crisp your negative is. 

What I've seen is that really good pin registered scanners can get a bit more out of a crisp negative at 4k than at 2k, but only a tiny bit. You do get more noise in the image however and the noise is crisper, so that's something to think about.

Whenever we get our Scan Station, I will do an A/B comparison. 

Tyler do you do commercial scanning?

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16 minutes ago, Robin Phillips said:

If you were finishing a film its probably worth a 4k scan if budget permits, otherwise ya may as well just scan at 2k and upscale.

One should never upscale the film, as you have to create picture data where there wasn't any before, and that will always degrade the image. See the example about halfway down the page here: https://www.gammaraydigital.com/blog/busting-resolution-myth

If the goal is to squeeze more picture information out of the film by increasing the resolution, that will depend on a bunch of factors: the film stock, the camera's focus, the lens quality, the steadiness of the film in the gate, the steadiness of the camera, the exposure, the lighting, and I'm sure more. The fact is, you can see more defined grain in a natively scanned 4k image than in a 2k image that was scaled up. You're using more pixels to make the initial image, thus you're taking more samples (think audio sampling - same idea). And the end result is that you get a better representation of the physical film, which is what holds the image. And that's the whole point. 

 

 

 

 

 

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On 7/16/2019 at 9:39 AM, Daniel D. Teoli Jr. said:

I was thinking 4K would give double the resolution over 2K.

 

4k is 4 times the "resolution" (that is, pixel count) of 2k. Assuming you're comparing apples to apples in terms of aspect ratio, a 2048x1556 file is 4x fewer pixels than a 4096x3112 file.  

But as mentioned in my last comment, you're not going to squeeze picture information out of the film if it's not there. But if you scan at 4k you are going to get a better scan, because you're starting with more digital samples of the analog image.

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We do a fair amount of 4K / 5K 16mm (Super, Standard and Ultra) scans

Definitely more detail and not just noise/grain IMO

 

True RGB scans often show more detail and sometimes those are a bit to revealing  compared to 4K CFA scanner scans which have less detail.

Also there are differences between scans which have more detail but look less sharp and scans which have a bit of sharpening added.

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4 hours ago, Robin Phillips said:

Tyler do you do commercial scanning?

Our business has been in process of moving since April, but when it's up and running again, yes we do commercial scanning. We have a few Imagica's for 4k 35mm, Spirit 2k/4k, a working blackmagic Cintel 2.0 (4k HDR) and soon will have a scanstation. Where I don't have much experience with the Lasergraphics products outside of having stuff scanned for me, I've seen the results and they're quite outstanding. The  Spirit 4k does have the upper hand at being a trilinear array, full 444 and 10 bit DPX raw, which is quite nice. It also has a very nice optical path. The down side is the poor registration and expense to keep the machine running. I do use it for nearly all of my own productions though and it's suited me well for the last two years. 

This trailer was scanned entirely on the Spirit in 2k, it's 3 perf 35mm mixed with 16mm cropped to 1.75:1. 

 

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16 hours ago, Tyler Purcell said:

Our business has been in process of moving since April, but when it's up and running again, yes we do commercial scanning. We have a few Imagica's for 4k 35mm, Spirit 2k/4k, a working blackmagic Cintel 2.0 (4k HDR) and soon will have a scanstation. Where I don't have much experience with the Lasergraphics products outside of having stuff scanned for me, I've seen the results and they're quite outstanding. The  Spirit 4k does have the upper hand at being a trilinear array, full 444 and 10 bit DPX raw, which is quite nice. It also has a very nice optical path. The down side is the poor registration and expense to ke

I had an Imagica Imager-XEplus which I gave away as it was slow as cold molasses and the Toshiba CCDs in those go bad and the one I had was noisy and could only pass a FPN calibration one out of five times.

I would also give away that BlackMagic Cintel as it has tons of FPN issues and the "HDR" means somehow that you have to run the film through twice? So not the elegant multi flash of a Scan Station.

The Spirit 2K/4K is the industry workhorse and is a true RGB 16bit scanner which is pretty fast (to DPX) and can be really reliable especially if you have a parts machine.

When talking to Steve about getting a Scan Station I would recommend getting the new Sony 4K CMOS sensor instead of the 5K CMOSIS one as they all have low DR and noise issues. The 2-Flash "HDR" on the Scan Station basically overcomes the problems with the 5K sensor so if you do go with that 5K chip I would not run the machine in any other mode than 2-flash. Other than that the Scan Station is a dead reliable workhorse Bayer sensor scanner. They really run like a top day after day..

But LaserGraphics also makes the Director which is true RGB.

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32 minutes ago, Robert Houllahan said:

I had an Imagica Imager-XEplus which I gave away as it was slow as cold molasses and the Toshiba CCDs in those go bad and the one I had was noisy and could only pass a FPN calibration one out of five times. 

We've been very lucky with our two units. I haven't seen ANY FPN in the scans. Very slow scanning is the only issue that I've personally had. But we have two of them and can load each overnight so in the morning we have something done. It's a real shame they weren't 3fps... I think ours in full resolution are close to 1.9 seconds per frame. EEK! 

32 minutes ago, Robert Houllahan said:

I would also give away that BlackMagic Cintel as it has tons of FPN issues and the "HDR" means somehow that you have to run the film through twice? So not the elegant multi flash of a Scan Station.

Only 1 out of 7 BM Cintels works. We've been trying to track down why this is the case, but it for sure is the case. Every one I've tested has HORRIBLE FPN, making the image worthless, EXCEPT for the one we have. IDK why it works, but it works really well. I wouldn't use it as a final because the registration can be finicky to get working right, but if you do get it working right, the thing does work great. When they release their new model (hopefully NAB 2020), it will be a marketable improvement with a higher resolution imager. 

The HDR mode is a gimmick in my opinion.  

32 minutes ago, Robert Houllahan said:

The Spirit 2K/4K is the industry workhorse and is a true RGB 16bit scanner which is pretty fast (to DPX) and can be really reliable especially if you have a parts machine.

I love the Spirit. I just wish we didn't need to use Bones. 

32 minutes ago, Robert Houllahan said:

When talking to Steve about getting a Scan Station I would recommend getting the new Sony 4K CMOS sensor instead of the 5K CMOSIS one as they all have low DR and noise issues. The 2-Flash "HDR" on the Scan Station basically overcomes the problems with the 5K sensor so if you do go with that 5K chip I would not run the machine in any other mode than 2-flash. Other than that the Scan Station is a dead reliable workhorse Bayer sensor scanner. They really run like a top day after day..

Good feedback, I will talk to him about that option for sure. When we get ready to buy, I'm going to demo one here in LA and I hope they have a 4k model around as well. My only concern is that we need to deliver true 4k images to customers and I'm scared if the imager is only 4k, it will be hard to do that once you re-frame things. 

 

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The new Sony sensor is 4112x3008 so good for UHD resolution as the scanner  has to "see" the perforation(s) for registration.

There is another Sony 6.5K sensor just becomming available but will not hit 30FPS scan speed, more like 15FPS but really good sensors.

Maybe BMD will put the 4.6K CMOS sensor in the Cintel and then it will be ok.

You can also get the 5K Scan Station but in single flash mode you will get FPN sometimes (not nearly as bad as the BMD) or run 2-Flash at 15FPS.

Lots of good choices in scanners these days and I think it will only get better as new sensors arrive, a buyers market.

Edited by Robert Houllahan
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Great answers here. Most important is maxing out what 16mm can do for you by using sharp lenses and proper focus & exposure and using the slowest film stock you can for the project. 4k scans will almost always be an improvement, how much of an improvement will be based on how well it's shot.

If the image doesn't hit the film sharp and clear, higher resolution scans will only give marginal improvements and may not be worth the cost. When it's shot well, 4k absolutely improves the final result even when finishing in HD. Plus you can reframe a little bit if needed which is nice.

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Hi somebody can explain what does FPN mean ? 
Here in Paris we have the LaserGraphic Scanstation since two years, and we have great results, some issues with the stability of the film that is less stable than the Scanity for example after our tests, especially in 16mm sometimes clients are complaining about that and purple noise in the highlights. We do not have the HDR unit, probably thinking about getting that soon.

Edited by Paul-Anthony
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7 hours ago, Paul-Anthony said:

Hi somebody can explain what does FPN mean ? 
Here in Paris we have the LaserGraphic Scanstation since two years, and we have great results, some issues with the stability of the film that is less stable than the Scanity for example after our tests, especially in 16mm sometimes clients are complaining about that and purple noise in the highlights. We do not have the HDR unit, probably thinking about getting that soon.

Fixed pattern noise.

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On 7/17/2019 at 4:47 PM, Tyler Purcell said:

Our business has been in process of moving since April, but when it's up and running again, yes we do commercial scanning. We have a few Imagica's for 4k 35mm, Spirit 2k/4k, a working blackmagic Cintel 2.0 (4k HDR) and soon will have a scanstation. Where I don't have much experience with the Lasergraphics products outside of having stuff scanned for me, I've seen the results and they're quite outstanding. The  Spirit 4k does have the upper hand at being a trilinear array, full 444 and 10 bit DPX raw, which is quite nice. It also has a very nice optical path. The down side is the poor registration and expense to keep the machine running. I do use it for nearly all of my own productions though and it's suited me well for the last two years. 

This trailer was scanned entirely on the Spirit in 2k, it's 3 perf 35mm mixed with 16mm cropped to 1.75:1. 

 

Beautiful work!

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On 7/18/2019 at 10:11 AM, Robert Houllahan said:

The new Sony sensor is 4112x3008 so good for UHD resolution as the scanner  has to "see" the perforation(s) for registration.

There is another Sony 6.5K sensor just becomming available but will not hit 30FPS scan speed, more like 15FPS but really good sensors.

Maybe BMD will put the 4.6K CMOS sensor in the Cintel and then it will be ok.

You can also get the 5K Scan Station but in single flash mode you will get FPN sometimes (not nearly as bad as the BMD) or run 2-Flash at 15FPS.

Lots of good choices in scanners these days and I think it will only get better as new sensors arrive, a buyers market.

I wouldn't call it a buyers market unless you have deep pockets. I keep buying lotto tickets in any case.

Are there comparison photos for FPN ranges?

Thanks

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On 7/21/2019 at 11:01 AM, Daniel D. Teoli Jr. said:

Are there comparison photos for FPN ranges?

 

FPN is different on every sensor, so probably not. To a large degree it can be compensated for with proper sensor calibration. Our ScanStation exhibits very little noise, except with the densest of films (a situation where there's not enough light getting to the sensor - when you try to pull details out of that dense film in grading, you expose the underlying noise). HDR scans basically eliminate this by doing a special exposure for the dense areas, by getting more light to the sensor.

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On 7/21/2019 at 11:01 AM, Daniel D. Teoli Jr. said:

I wouldn't call it a buyers market unless you have deep pockets. I keep buying lotto tickets in any case.

Are there comparison photos for FPN ranges?

Thanks

Well I have two last Gen Spirit 2K/4K machines and one was delivered in 2007 and the other was delivered in 2008 and someone paid a total of $3.2 Million dollars for them.

A fully kitted out Scan Station is about $200K and I think a Director is maybe $500K and a Scannity is $1M The BMD Cintel is $30K? And it would probably be pretty decent if they put the 4.6K sensor in it instead of the junk UHD/4K one.

Pretty significant drops in pricing on motion picture scanners, a BMD or a Scan Station Personal at $30-$60K is even in the range of an enthusiast IMO.

 

FPN is not a "range" it is grid like noise in the sensor and usually shows up in the shadows of a positive film scan and in the hilites on a negative film scan.

Look at FPN in the shadows on cameras like the REDs for examples.

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