Some facts after a quick analysis of both +HTC #ONEm9 and +LG Mobile Global #LGG4 produced DNG

– Both lack flat-field correction
– Both provide incomplete matrix-only color profiling: no DCP
– Neither use compression
– HTC One M9 DNG is 10 bit stored in 16bit uncompressed data: 39MB per 20 Mpixel image.
– LG G4 DNG is 10 bit stored uncompressed, 20MB per 16 Mpixel image
– Both have non-optimal noise profiling settings: HTC One M9 set noise reduction too high and LG G4 lacks noise profiling entierly.

Notes on flat-field correction:
Mobile camera modules require such correction to correct both vignetting and color cast (like pink spot / greenish or blueish corners).
HTC One M9 requires less correction than the LG G4.
It is only possible to compensate for light fall-off, in RAW image editors, not color cast.
As a result, the color cast in corners is essentially non-fixable.

Attached: the #LGG4 DNG sample provided by +Colby Brown rendered in Lightroom with only modification an increased contrast and exposure slightly, to make both vignetting and color cast more obvious.

The least I can say is that there's room for improvement, both DNG implementation being non-optimized and incomplete.

#supercurioBlog #LG #DNG #color #camera #calibration


Source post on Google+

Published by

François Simond

Mobile engineer & analyst specialized in, display, camera color calibration, audio tuning

25 thoughts on “Some facts after a quick analysis of both +HTC #ONEm9 and +LG Mobile Global #LGG4 produced DNG”

  1. +Cedrik L Not necessarily: one can actually upload full, uncompressed .DNG files as well as untouched JPEG files to Google+ without them being compressed by the platform… Facebook and other sites however, will recompress and downscale them.

  2. +Cedrik L​​ needless to say that the attached picture is without auto awesome or any other G+ effect (it's disabled entirely in my account's preferences, you can do it too.)
    The vignetting and Green/Blue color cast is the one from the G4 lens and sensor.

  3. +François Simond​​, what is causing the speckled blue arch that comes from the top on the rock out and down to the left? Is that present in the DNG file?

    (As far as I know, you can upload them straight without going through light room to get a JPEG… I've done it before with my OnePlus One.)

    Edit: that makes sense not relying on Google+ to present the RAW if most software does it differently. I figured it was mostly the same.

  4. +Taylor Wall what makes this oval shape is the vignetting and corner color cast added to the sky itself.
    If things look speckled, it's the result of compression G+ re-compression artifacts on the sensor noise, which is why I I would recommend to download the original file I uploaded, which is a 16MB JPEG.
    This was rendered with Lighroom CC on destkop BTW.

  5. +François Simond of course it is, but it isn't shown uncompressed on the g+ stream. Otherwise it would take some time to load it with my connection. Contrary, it's instantaneously loaded, so no 16 MB pic on the stream.

  6. +Chris Dartois the quality of profiling doesn't matter to me because I can build mine and rewrite the DNG files.
    To shoot in re-profiled RAW:
    I would choose the G4 because it has an OIS and better AF which matters most usually.
    However for landscapes in good light I would pick the M9 because its 20 Mpixel sensor is also equipped with a sharp lens.

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