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20 responses to “12Bit Vs 14Bit Raw And Compressed Vs Uncompressed… Does It Matter?”

1. 

   Gert Arijs

   Apr 7, 2013

   Interesting experiment. I’d love to see the same with ISO 800 or 1600 and I assume that it ‘ll make a significant difference. But that’s what I thought to happen here too and I thought wrong.

   Reply
   1. 

      lmm

      Feb 15, 2015

      I’d love to see the same with ISO 800 or 1600 too.

      Reply
2. 

   Francesco Riosa

   Apr 7, 2013

   This test make sense only for ISO 100, because is the one which has the maximum bit depth.
   The sensor is actually GRGB, it’s possible to assume that the maximum performance is on Green colors, it would been interesting to test that too.

   Also, I’m still for shooting in 14bit uncompressed, if images don’t need that extra 0.024% precision they can be converted in lossy DNG which compress better and is a standard format.

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3. 

   Kornél Lehőcz

   Apr 7, 2013

   The difference between 12 and 14 bits isn’t insignificant with the newer sensors at ISO100, as also these test images demonstrate. The difference would probably be more striking if you had turned off noise filtering in Lightroom. But you can observe some rather bad misscolouration on the 12 bit image also like this, and loss of detail on the gray brick texture. Yes, the extra 2 bits are usually the least significant bits, so you would only see the difference in the underexposed images.

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   1. 

      Anton Zuykov

      Jan 1, 2014

      “so you would only see the difference in the underexposed images”

      that is not correct — least significant bits work well in overexposed areas too…
      They are simply the measurement stepping with which a ADC digitizes analog voltage values and the sensor is linear always.

      it simply determines stepping between two brightness values – so, 12 bit demonstrates bad colors and 14 doesn’t – it simply has more color information than 12 bit image.

      Reply
4. 

   David Habot

   Apr 7, 2013

   I think your test may be wrong. You should provide us the RAW files to check them on our own computers. JPG and PNG files that you provided us are just 8 bit of which the JPG file is just sRGB but the PNG files have no profile.

   The next problem I see is that you didn’t tell us which monitor did you use to make your comparison?
   If you used a wide gamut monitor there would be a greater chance to see a difference especially at a gradient fill. But if you used an ordinary sRGB monitor like Apple Retina or any of TN type of displays there is not such a chance you would see a huge difference.

   Just my opinion.

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   1. 

      Francois Malan

      Apr 7, 2013

      David – Here is the link to the original NEF files.
      https://www.dropbox.com/s/7pxnq8ecnrw7lyn/RAW_12bit_vs_14bit.zip

      If you find anything different, feel free to share.

      Reply
   2. 

      JR

      Feb 28, 2019

      It doesn’t matter if JPGs are 8 bit in this case.

      Reply
5. 

   Felipe Arruda

   Apr 7, 2013

   I’ve made these tests years ago with DNG conversion:
   http://fotoemoto.wordpress.com/2011/07/21/tipos-de-raw-na-nikon-d7000/

   The results:
   14bits Lossless: 21.0mb(NEF) 18.8mb(DNG)
   14bits Comprimido: 18.7mb(NEF) 16.6mb(DNG)
   12bits Lossless: 16.7mb(NEF) 14.5mb(DNG)
   12bits Comprimido: 15.2mb(NEF) 12.8mb(DNG)

   Bud today you have a Lossy compression with DNG that works BETTER with 14bit losless RAW.
   So today I shoot with 14bit lossless always, then after the work is done, store with lossu dng!
   Simple and great!

   Reply
6. 

   Francois Malan

   Apr 7, 2013

   Hey everyone – I’m the guy who wrote this article. If you go to my original blog post (link at the bottom of the post) you will see that I’ve since updated it with a link to the original NEF files. So David Habot – go for it. I’m pretty sure that I tested this correctly, but you’re welcome to try and replicate the results.

   Some people asked about higher ISOs – if you read the thorough article on noise vs bit depth that I linked to, you’ll see that higher ISO values imply higer noise, that will mask the differences between 12 and 14 bit even further.

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7. 

   Chris

   Apr 8, 2013

   I’m not sure this is the best test methodology, but it’s sufficient to show that you certainly got extra usable data from the 14-bit file. The reason I’m not sure it’s the best is that you seem to be assuming that the 12-bit curve has less dynamic range than the 14-bit curve, presumably because when you map a 12-bit sensor curve (with 12-14 stops of DR) onto 8-bit sRGB (with about 6) or even 8-bit AdobeRGB (with about 8) you’re picking a curve suitable for display at conversion time and throwing away data outside the DR of a typical display. That’s not what the camera is doing when it uses 12-bit instead of 14-bit. If the camera is in fact just throwing away the two least significant bits then I would expect to see no worse performance at the extremes of DR than in the middle, it’s just that if you stretched the curves for a patch of blue sky out incredibly far it would start to get banding on 12-bit before 14-bit.

   I suspect, though, that that’s not really what Nikon is doing, and I suspect that because your 14-bit file has considerably better tone on everything but the bottom bricks than the 12-bit file (there was more green and less red there in 12-bit than there really was, probably because of how demosaicing worked on the GRBG sensor array) which shows that you are throwing away useful color data in 12-bit if you needed to resurrect something 5-6 stops under.

   It’s hard to know if this is a good test of compression or not. A lot of modern lossy compression engines would work really well on crisply defined geometric patterns like this and then fall apart completely on smooth curves and textures (like, say, a long exposure of a waterfall). I suspect there’s an extremely low compression level in RAW compression so it would probably be pretty hard to construct a test where you can really see the difference.

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8. 

   w00d

   Apr 8, 2013

   Hello all … First of it’s a given my limited photographic experience doesn’t qualify myself to make recommendations but when saving my images it is commonly recommend or I’ve always been told to archive in the highest resolution and colour bit depth my camera is capable of producing. This would also included shooting the widest gamut my camera is capable. It’s certain my cheap $200 Kmart monitor is not capable of viewing the images my Nikon D90 produces at their best. However my future plan is to buy wide gamut monitor or a professional photographers monitor. Therefor in anticipation of the day when I upgrade I don’t want to be tossing image data out the window (sorry for bad pun) simply because I don’t see any difference on my current hardware. I would have to guess the end result of all the seemingly insignificant improvements produce diminished returns at best if looked at in their singular. However when added up with all the minor improvements offered by current and future hardware then the benefits could be significant or very much visible. Again I’m still learning, looking for the ‘best’ information and recommendations but is my logic incorrect or flawed in a way I’m not seeing?

   Reply
9. 

   Asher

   Dec 18, 2013

   In this experiment you limited the data by blowing the highlights. You can instead try to overexpose it but not so much as the clip the data on the right side of the histogram, and then compare the images. You’re comparing hardly any data to hardly any data instead of lots of data to lots of data. You’ll get more distinguishable results using the latter.

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   1. 

      Asher

      Dec 18, 2013

      Also the depth of field is different in the two images. It would make more sense to up the exposure setting instead of changing the aperture. They aren’t the same image otherwise.

      Reply
   2. 

      JR

      Feb 28, 2019

      Not all the data is blown out. You can tell in the transitions. You have to blow it out like this to find differences.

      Reply
10. 

    A K Nicholas

    Jul 10, 2014

    Thanks for the tests and opinions. Its important to consider your target subject and display method. If you are producing images for print, a wider range of colors are relevant than display on the web. I see color variations in the images above, for work with skin tones, that may be more relevant. I have different workflows going to Flickr than I do going to a photobook. At the end of the day we each find what works within our own parameters.

    Reply
11. 

    Jay Strange

    Sep 9, 2014

    My understanding (which may be wrong) is that the 14 bit files will allow you to recover some detail from the dark shadows and highlights which you may not be not get from 12 bit files. So the difference is in processing not in visual examination from the unprocessed files.

    Reply
12. 

    jjsimonette

    Jul 23, 2016

    Actually I wouldn’t say my eyes are particularly well trained and I found some of the the differences between 12 and 14 bit quite easy to spot. I just as easily spotted them here in your sample photos so I can’t say I agree with the conclusions arrived at in this article. Primarily there seems an obvious (to my eyes) increase in image clarity and sharpness.

    Reply
    1. 

       gl

       Nov 16, 2016

       Mine are well trained, and I see exactly the same thing on the flowerpot, clearly sharper and more detail with all the lossless versions (regardless of bitdepth). This is expected as compression will throw away fine detail first.

       Now whether it matters depends on how you shoot, and how large you print (and/or how heavily you like to crop). I do very large prints, and that difference is significant to me. And anyway, I would always want the detail in case I need it, even if I often don’t. Storage is far less of a problem than it used to be (especially once you start shooting RAW video : ).

       Reply
13. 

    Szabolcs

    Aug 22, 2017

    I do wonder how much of the difference we see between the 12- and the 14-bit files is really due to the bit depth, and how much is due to implementation differences between 12- and 14-bit readout modes.

    With a D7100, I can see clear differences in banding patterns between 12 and 14 bit files (shadow banding is noticeably worse in 12-bit mode). Extracting the data from the RAW files reveals that the camera switches to digital amplification above ISO 3200 in 14-bit mode, but still uses analog amplification at ISO 6400 in 12-it mode.

    Previously, I assumed that the sensor data is always read out the same way, at 14-bit resolution, and then downsampled to 12-bit in software if that type of NEF file was selected. The above observations suggest that this is not the case.

    Of course, for practical purposes all that matters is the quality of the resulting images, not the reason behind that quality difference …

    Reply