Scanning Files: Spirit Telecine vs. Arri Scanner

From TIGwiki2
Jump to: navigation, search
  • From the TIG archives

From Ravi Ravi Kumaar Mar 16, 2007

Hi

I want to know the file quality scanning from the telecine spirit datacine 2k or 4k compare with Arri laser film scanner.

The spirit telecine have real time scanning but the image output is only video quality ( am i right?).,

The arri scanner have presently have speed option but the quality?

Which is the best for DI pipeline? Spirit data cine or Arri Laser Scanner?

Waiting for results....

See you.

Ravi


From Adam Inglis, Mar 16 2007

The spirit 4k can output 10 bit log data like the arriscanner. However, as far as i am concerned from a colourist point of view, when it comes to DI work the arriscanner wins on a couple of factors - the arri's pin registration means better image stability, the scans can be used for vfx work and you dont end up mixing scans from different machines, secondly the arriscanner is calibrated to the stock you are scanning, so you get a better representation of your negative. The arriscanners speed upgrade does not affect the quality, although its not real time like the spirit. It would be worth looking at the northlight too, if you havent already.

Adam Inglis Colourist Deluxe Digital Intermediate, London


From Craig Nichols, Mar 19 2007

The Spirit 2k/4k can output 2k data (2048 x 1556 RGB 10 bit or 16 bit) in real time. There is a separate video output available as an option. It is also possible to transfer 10 or 16 bit dpx files in 4k at 6fps.

The Spirit 2k/4k is available in a variety of configurations that can be tailored to best suit your needs. For instance, you can order the machine with 2k options and upgrade later to 4k. Or, you can start with a video machine and later upgrade to data.

As far as which one is best for your facility, I am biased as I work on Spirit 2k/4ks, for Thomson Grass Valley.

In response to Ken Robinson's question about Fuji, we have had clients get quite pleasing results with FUJI as well as Kodak stocks.

Craig Nichols Senior Tech Support Engineer Digital Film Applications Thomson Grass Valley Burbank Craig.Nichols at thomson.net


From Adrian Hauser, Mar 20 2007

"Nichols Craig" wrote

>The Spirit 2k/4k can output 2k data (2048 x 1556 RGB 10 bit or 16 bit) >in real time. There is a separate video output available as an option. >It is also possible to transfer 10 or 16 bit dpx files in 4k at 6fps.

Hi Nichols, How does the Spirit deal with pin registration and Base calibration of the OCN and hence being able to reproduce identical scans (in registration and density) of different resolutions? Ie: you scan SD or 1k proxies in LOG (grading your rushes in DI) for editorial and early VFX temps, and then rescan the full res for the final DI and VFX components.

Adrian Hauser

Digital Film Colorist DI Operations Manager Complete Post Australia


From Craig Nichols, Mar 21 2007

Adrain,

Base calibration is handled by Auto Dmin option. Proxies can be generated in many different data sizes from SD to 4k. Pin registration in not being done on any real time LINE array CCD scanner that I am aware of.

I work for Thomson on digital film application products. I am not a marketing guy.

Regards, Craig Thomson Grass Valley Sr. Tech Support Engineer Digital Film Products


From Liao Zhuodi, Mar 16 2007

Hi, Bob,

I have look it up in our the pdf manuals, and I do not quit follow it, is that related with the saying:"685 (highlights) and below 95 (shadow detail)."


5.1_Logarithmic vs Linear Colour Space

One day, there was a company called Kodak, who set out to define the way digital film images would be recorded.They came up with a format called 'Cineon' in which the brightness of the R,G&B layers was represented as film density.

The negative density of 2.048D above Dmin was recorded into a 10-bit space with values from 0-1024 representing the usable contrast range of the negative film. Unfortunately for users, monitors displayed brightness with linear values, generally from 0-255 for each channel, so when displayed on monitors, Cineon files looked washed out.

Cineon images are generally stored in 4 bytes (32 bits) of information, and captured all of the available tonal detail on the original negative film. As some of the maths involved in image manipulation requires images in linear space, there are a number of ways to convert from log to linear to facilitate compositing.

One method involved linearising the image in the range of 0-65535 in 16 bit space, with 90% white (Cineon code value 685) set at 65535.This method made the images easier to view on monitors, but clipped off any highlight detail above 90% white.

Another method involved linearising with the 90% white code value set to 4095, retaining the highlight detail, but making the images difficult to view on workstation monitors as they generally displayed at only the upper 8 bits on the 16 bit image resulting in dark images. There are also other methods, including 8 bit linear with 90% white at 2255, 12 bit linear with 90% white at 4095, etc.

Liao Zhuodi System Engineer Hualong Film Digital Production Phone: +86(010)-82041113 Ext.123 Mobile: +86-13671379401 Web: www.hualong-digital.com Email: Liao.zd at gmail.com


From Ken Robinson, Mar 16 2007

Subject: FW: [Tig] Scanning files: spirit Telecine VS Arri Scanner

> Adam Inglis

> The arriscanners speed > upgrade does not affect the quality

I have been doing some investigation of my own, and this is not quite the case, or at least as I understand it. The double flash not only increases exposure of the film, but also hides the gaps on the CCD. Thus the quality will be lower at the single flash speed. Please correct me if I am wrong...


> secondly the arriscanner is calibrated to the stock you are scanning, > so you get a better representation of your negative

I was also looking at the Spirit stuff.... And this is how I understand it: Spirit has RGB filters designed to give perfect separation of RGB values (as they are designed by Kodak... Does it work for Fuji as well???). There are setups for specific film stocks and you can make corrections in a Printer Lights mode.

There are still a few other factors in considering which scanner is best (for your facility).

Ken Robinson Senior Colourist VTR BEIRUT Tel: +961 1 208 802 Mob: +961 3 074 186 www.vtrbeirut.com


From Adam Inglis, Mar 16 2007

The arriscan speed upgrade i was talking about was a recent upgrade arri did to make them faster, i didnt really consider the option of scanning using a single pass. So yes, I would agree with you about the double / single flash quality issue on the arris.

When it comes to stocks, i was concerned about the gammas of RGB, not the separation. As far as i am aware the gammas are user defined on the spirit...

Adam Inglis Colourist Deluxe Digital Intermediate


From Martin Parsons, Mar 16 2007

Ken Robinson wrote:

> The double flash not only increases exposure of the film, > but also hides the gaps on the CCD. Thus > the quality will be lower at the single flash speed.

As I remember from the ARRI NAB User group meeting, there was an introduction of 'rushes quality' scanning at 8 frames per second. The speed increase was achieved by only flashing once each scanned frame giving an unacceptable signal-to-noise ratio only in film densities over 1.0

Have a good weekend all

Martin


Martin Parsons Head of Imaging The Moving Picture Company London www.moving-picture.com


From Adrian Hauser, Mar 16 2007

e have been using the Arriscan with the high speed option for both TVC and DI work here at Complete Post in Melbourne.

For a reasonably exposed OCN the difference between the high speed 2k single flash 7.6fps and low speed double flash 4fps is, to the eye, exactly the same.

I have done tests on overexposed negatives which produced no visible differences between the 2 modes. I am doing some tests on some underexposed material this weekend if anyone would care to see the results.

I should set some things straight about speeds on the arriscan.

  1. - The High Speed option will run at an average of 7.6 fps for 35mm 2k

Full Gate images with its Single flash mode.

   - The above while producing increadibly good 1k proxies at the same time 

will lower the speed to about 6.5 FPS.

  1. - In 35mm the Arriscan has an extremely fast spooling mode of 3m per sec.

This means that one can effectivly perform a select scan of the OCN from loading an EDL extremely quickly. The average TVC can be scanned easily within about 50 minutes, including stock calibrations, setup and EDL prep and healthy 5 sec handles!

  1. - The Normal Speed "double flash" mode will run at an average of 4 FPS

for 35mm 2k Full Gate images.

  1. - The scanner can also produce ALE or FLEX files of lab reels while

working in its "digital dailies" mode. Using its built in keycode reader to identify stock changes in an prepped lab reel, of say 3 camera rolls, the software can also auto apply your saved stock Base calibrations 'on the fly' when in Auto mode.

Adrian Hauser Digital Film Colorist Complete Post Australia

> > > Ken Robinson wrote:

> As I remember from the ARRI NAB User group meeting, there was an > introduction of 'rushes quality' scanning at 8 frames per second. The > speed > increase was achieved by only flashing once each scanned frame giving an > unacceptable signal-to-noise ratio only in film densities over 1.0 >


--Rob Lingelbach 08:06, 23 March 2007 (PDT)