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Imatest Info DR (Information-based Dynamic Range) refers to an Imatest module and a set of test charts designed to measure C4 information capacity over a wide range of illumination — Part 1, describes the InfoDR charts and how to photograph them. Part 2 describes how to run the InfoDR analysis. This post, InfoDR Results, shows C4 summary results for a number of cameras. |
This post presents InfoDR results for a variety of cameras that we were able to test. In all cases, raw files were converted with LibRaw into 48-bit Adobe RGB (color space) files with minimal processing — no sharpening or noise reduction. Maximum exposure was kept a little under saturation (around -0.05 to -0.1 in units of log10(DN/DNmax). Results were mildly (but not strongly) sensitive to exposure. Saturated or near-saturated regions were omitted from the calculations. High quality lenses were used where possible, at optimum aperture (F-number): f/5.6 or f/8.
Many of the cameras were quite old, with no computational imaging or Artificial Intelligence to distort the results.
We used the first version of the 2-layer LVT film InfoDR chart. The final version may have slightly reduced “sawtooth” patterns in the lower (log(pixel level) vs. log(exposure)) plot, which are likely caused by stray light from lighter patches.
Summary table
Abbreviations: FF = Full Frame (24×36mm sensor).
| Camera | Pixel size μm |
Total Mega-pixels |
F-stop, Shutter speed |
Dyn. Range dB High, Low |
C4(total) b/p, MB total |
Description |
| Lumix LX7 | 2.14 | 10.1 | 5.6, 1/50 | 29, 38.9 | 2.49, 25.1 | Compact camera with Leica-branded zoom lens |
| Lumix G3 | 3.77 | 16 | 8, 1/40 | 22, 36 | 2.90, 46.3 | Micro 4/3 mirrorless interchangeable |
| Sony A6000 | 3.9 | 24 | 8, 1/20 | 23.8, 50.7 | 5.65, 137 | APS-C mirrorless interchangeable |
| Lumix FZ1000 | 2.41 | 20 | 8,1/30 | 19, 38.6 | 2.38, 47.8 | 1″ sensor with extreme zoom lens |
| Sony A7Rii | 4.51 | 42 | 8, 1/20 | 38.1, 49.9 | 5.79, 246 | Mirrorless, FF BSI sensor |
| Sony A1 | 4.16 | 50 | 8, 1/20 | 37.9, 53 | 5.6, 281 | FF Stacked sensor [A] |
| Sony A9 | 6.19 | 24 | 8, 1/20 | 40.3, 54.1 | 6.19, 150 | FF Stacked sensor [A] |
| Pentax K-1 | 4.88 | 36 | 8, 1/30 | 38.5, 50.9 | 5.7, 207 | FF [B] |
| Pentax 645Z | 6.58 | 51 | 8, 1/25 | 42.5, 57 | 6.58, 337 | Medium Format [B] |
| Leica M9M | 6.92 | 18 | ?, 1/60 | 25.8, 44.5 | 3.87, 70 | FF monochrome rangefinder. Some misfocus or lens misalignment? [B] |
Interesting as the results are, we didn’t find any major surprises. High quality (expensive) cameras seemed to deliver on their promise.
Thanks to Bruce Henderson [A] and Shel Gottlieb [B] and for bringing in several excellent cameras to test.
Detailed results
The file name in the top line of each image contains the camera model name, focal length, aperture (f-number), ISO speed, and exposure time with ‘/’ replaced by ‘-‘ (for example, 1/30 second is ‘s1-30’.
To compare results, please note that the x and y-axis scales are different for different plots, i.e., you need to look at the (automatic) scale or C4(total).
| Panasonic Lumix LX7
|
Panasonic Lumix G3 |
Sony A6000 Canon 60mm f/2.8 macro lens with full manual control, allows the magnification to be set. We use it for testing our test charts. Exceptionally low stray light. |
Panasonic Lumix FZ1000 Leica- zoom. Non-interchangeable. 25-400mm equivalent. |
Sony A7Rii The three Sony Full-Frame cameras (A7Rii, A1, and A9) used the same lens: the excellent 90mm f/2.8 macro at f/8. |
Sony A1 Thanks to Bruce Henderson |
Sony A9 Thanks to Bruce Henderson |
Pentax K-1 Thanks to Shel Gottlieb |
Pentax 645Z Thanks to Shel Gottlieb |
Leica M9M Thanks to Shel Gottlieb Cause of C4 bump is unknown. There seems to be some misfocus and perhaps misalignment. I think the lens was a Leica 35mm f/2.8 Summaron, which was made from 1958-1974. (I’ll check.) |
