All Things Color for Film and Digital Cinema
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On-Set Monitoring

Coming Soon for Android – 2014 – Cinematography Color Grading Assistant application

Screen Grabs from my new Color Grading Application for Android.


Color Grading Modes

  • Collaborate, Share and Manage OnSet “Looks” between DP, Colorist and OnSet DIT.
  • 3D Lut Support
  • Grading Modes – Levels – RGB Exposure ” Printer Lights” – 3 Way Color Correction
  • Database support for “look” tracking and management.
  • Includes effects for additional image treatment. (NB: THESE FUNCTIONS ARE NOT ASC CDL ‘AWARE’ )
    • Textures
    • Vignettes
    • Frames
  • All operations are “Live” and not compounded operations as in many other Android image processing apps.
  • or simply use as a professional Color Grading app for your Phone Stills (Lite Version) saving as PNG or JPEG.

3 Way Color Correction


Effect Modes – Vignette | Texture | Frames | Color Map


All parameters are Live – No pre-rendering required between modes

Application includes:

  • 3d LUT support:
  • ASC SOP color Grading
  • Additional Image Effects
  • Android Screen Color Calibration
  • Export of ASC CDL grade files for Import into any color Grading Application.
  • Internal Database for managing grades:
    • Project Name
      • Shoot Day
        • Clip Name
  • Export Options:
    • “Extended Metadata” ASC CDL .cc file
    • Graded Reference Still
    • Original Ungraded Still
  • Preferences:
    • Help functions On / Off
    • User Name | Project Name | Shoot Day
    • Background Color
    • Load User Luts
    • Screen Calibration




iRiS S3D StereoScopic Base and Disparity Calc – new Skin Released

S3D Calc New Skin - template

New skin released with a few UI improvements.


Video Waveform Visualization and Creation

As an addition to the prior post on waveforms here we examine a more visually descriptive way of showing how a video waveform is created and therefor how it can be interpreted.

Fig:1 Waveform and Live Image

Above we can see a standard Live Video Feed and its represented waveform.

Below I have created a 3Dimentional Luminance map of the same live feed. In this representation every pixel on the image is represented on the z-axis as a luminance value bw 0 and 1023 video code values. The ‘lighter’ or more intense the pixel value the higher it appears on the z-axis.

Fig: 2 Luminance Relief Map  Face On

As I rotate this image in 3D space, around the y-axis, you can see the luminance values more clearly represented as a Height map in the 3 Dimensional space.

Fig: 3 Luminance Relief Map Rotated 45 Degrees

When finally rotated a full 90 Degrees we end up with the Waveform interpretation.

Fig: 4 Luminance Relief Map Rotated 90 Degrees

Adrian Hauser

Waveform Vs Histogram interpretation in Digital Cinema Cameras

Understanding how to read Histograms present on many new digital cinema cameras can be tricky and are easily misenterpreted.

For analysis, I will use the below still from the film Daybreakers as reference.

Ethan Hawke in "Daybreakers" (2010)

The following snapshots have been taken using DpxRead available on the Panavision website.

Immediately we can see that there is a massive difference in the way these two images are represented in each of the graphical/statistical graphs.

Histograms represent the volume/percentage of light levels exposed within a particular image. The resulting graph shows the distribution/intensity plot of those levels.

Histogram Exposure

The above image reference image  is quite ‘moody’. The histogram shows us this quite literally but surprisingly shows nothing of where the midtones sit. This is because Histograms work with percentages and Ratios of light. If for the most part an image is dark, say 60% of the overall area , then the rest of the histogram has to be interpreted with the remaining 40 percent of image area. For that reason the intensity represented by the histogram for the remaining light values is visually a lot lower than the Dark spike shown in our reference.

To better show the way a histogram graphs an images lightness values I have put the below gradient into the scopes.

Linear Grayscale Ramp

We can see that because there is an even amount of each light level within the gradient image the Histogram shows an even intensity/distribution of each ‘level’.

Video Waveforms on the other hand give us a lot more visual information with which to evaluate your exposure and contrast ratio. As well as showing us the distribution of light values the graph is also plotted across the horizontal plane of the image. With this additional ‘axis’ one can easily determine where within the frame a particular item sits in its digital exposure value. This makes it easy to find for example the exposure of someones skin tone in relation to the background subject matter.

Histograms are Cheap and Easy to display from a programmers POV but in my opinion are quite useless in representing photographic content and should not be used for indepth exposure analysis.


D-Lux. Website Live


See Website for more details.

DLux software update

Update and Progress – Dlux Onset monitoring software.

Recently I’ve been quitely buying and studying books on Cocoa programming and OpenGL programming to give the Dlux application more functionality.

Recently added:

- added ASC Color Correction and ASC saturation parameters

- Improved Output of XML and Imaging data to include ASC color SOP data together with 3DLut information.

- Improving handling of Raw Cannon and Nikon DSLR images (intended for film jobs where DOP can send stills of graded DSLR with grading info to rushes facility. 

- Improved handling of Live HDSDI video streams and Live Firewire HD Streams. 

- New release date scheduled for before IBC.

- Improved UI updating when recalling saved presets.

- integrating Full Screen Mode for single or double screen use with external monitor.



DLUX Updated GUI with ASC Color Correction



D-Lux  screen_capture

D-Lux screen_capture

iRiS-LiveLut – Mac OSX – application update

An update on my OSX software ‘LiveLut’ which had some major coding breakthroughs over the last week.

Over the last few days I have successfully implemented the following features:

3DLut and color correction 25 fps ‘realtime’ previews to :


- Stills


- Quicktime Movies


-and Live incoming Video. (excuse the dodgy iSight camera)

All on a Mac Book Pro.

It still needs a bit of love on the UI side of things although that should not take too long.

I also added a live data view showing the associations between Density, Code Values and Printer Lights from the ‘exposure’ based color changes.

And the ability to save reference stills. (some time in the future i’ll incorporate the ASC color data translation ;)

The initial release of the software will be a simple pared back version available for film-makers to reference when making Photochemical timing adjustments to Answer Prints. The second version will incorporate the Slope Offset and Power Color tools for reviewing Quicktimes with a 3Dlut applied. The third release of the software will enable on set previews of live images direct from the source. The out put can be tapped to an external DVI or HDMI enabled monitor. 

User 3DLuts can be made and loaded into the program.


18 Percent Grey …. “Middle Grey” and Magic Numbers


    For a while I have been pondering the function of the 18 percent grey card. Why 18%, what is its historical reference…ect.

    After a lot of reference reading I came up with the following ….

    Traditionally 18 % refers to the statistical average reflectance of a photographed scene. ‘Normally’ exposed skin tones also generate an average incident light reading of about 18%.

    Photographically, if you were to make a set of 11 patches starting with 100% reflectivity and each subsequent patch was halved in reflectance, you would end up with a logarithmic scale where the light intensity is being halved each patch. The seventh step, middle grey, would yield a photographic Status M Neg density value of 0.7

    Using our Density math described in previous posts we know Transmission = 1/10^Density   

    Therefor    T=1/10^0.7= 0.18      AND       Transmission is directly proportionate to Luminance L*. Not boring you with the math the result is 49.496.

   So    0.7 Density = 0.18 Transmission = 50% Luminance(L*).



Fig.A - Status M against Status A Density

Fig.A - Status M against Status A Density



  Interestingly If we map our 21 step sensitometry readings of a 21 strip grey scale test wedge over Neg and Print densities we see that 0.7D is the cross over point !   See Fig.A









Looking at the image below, Fig.C, you will notice that this point of around 18 % grey is the mid point at which the cineon Log file is expanded when overlayed with a Print emulation 3DLookUp table. Both Mid Grey LAD Patch’s are almost identical as seen on the corresponding waveform Representations. 






Looking at the graph in Fig.C one can also see the reference point of 18 % on each of the mapped targets averaging around 50% luminance. Interestingly with this chart I have mapped Cineon Log levels against the 2.2 and 2.5 video gamma transfer functions and CIE Luminace L* values. They are all relatively close to each other in their Logarithmic encoding. I can see im going to have to rewrite this as its going to get messy from about here on in, although quite fascinating. 2.5 gamma looks like its the best match for CIE L* but somehow we got stuck with 2.2. Near enough is good enough I guess. It was decided back in the 8Bit video days that to help save on visual data that video/TV could also have a perceptual gamma encoding, once again mimicking the eyes response to nature. A gamma of 2.2 was decided apon.  




Protected: On set monitoring Luts for Digital Film Acquisition

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Live MBPro LUT monitoring application

Live MBPro LUT monitoring application


Live-LUT is a Mac Book Pro application for viewing live camera images via firewire on your Computer display. Live-LUT  allows users to apply 3d-LUT’s over the image and perform simple Lab-Style printer light Color corrections. 

Live-LUT can also be used to view LOG image sequences in the same context. Using the printer light controls Live-LUT can show you the result of lab printer light adjustments and their effect on the resulting release print.

Beta testing now.


To monitor with a HD CRT on-set or not. Focus issues

zone_plateA number of digitally acquired feature films I have been recently working on had a number of surprising focus issues not before seen until projected full screen in its native resolution. Surprisingly the same images didnt look as soft and appeared a lot more acceptable on a HD CRT monitor in the same room.

As these display devices are not a true pixel for pixel representation of the captured image I would not recommend using them for critical focus judgement. Color yes but critical focus….. no. This is not the first time I have seen this.

Screen your rushes in native res each day if possible or also have a SDI tap to a HD flat screen Display. Perhaps winding up the sharpness on the CRT may work  as well. I’ll test this myself. 

Film images seem to be a lot more forgiving in this regard due to the apparent perceptual sharpness effect of the grain.