Resolution Chart Comparison (Raw)

Shots here are of our 'version two' resolution chart which provides for measurement of resolution up to 4000 LPH (Lines Per Picture Height). A value of 20 equates to 2000 lines per picture height. For each camera the relevant prime lens was used. The chart is shot at a full range of apertures and the sharpest image selected. Studio light, cameras set to aperture priority (optimum aperture selected), image parameters default. Exposure compensation set to deliver approximately 80% luminance of white area.

For a (more) level playing field we also convert our resolution tests using Adobe Camera RAW. Because Adobe Camera RAW applies different levels of sharpening to different cameras (this confirmed) we had to use the following workflow for these conversions:

  • Load RAW file into Adobe Camera RAW (Auto mode disabled)
  • Set Sharpness to 0 (all other settings default)
  • Open file to Photoshop
  • Apply a Unsharp mask: 80%, Radius 1.0, Threshold 0
  • Save as a TIFF (for cropping) and as a JPEG quality 11 for download

Please not that for this comparison we converted the E-620 and E-P1 RAW files in Capture One (using the default settings). This is because we have reason to believe that Adobe Camera Raw doesn't show the full resolution captured by recent Olympus SLRs (Capture One shows visibly more detail).

Panasonic GF1 (2.9MB, 12.0 MP) Olympus E-P1 (1.6MB, 12 MP)
Olympus E-620 (4.1 MB, 12.3 MP) Canon EOS 500D (4.4MB, 15.1 MP)
Nikon D5000 (3.5 MB; 12.3 MP) Panasonic LX3 (2.2 MB, 10 MP)

Panasonic GF1 Olympus E-P1
Olympus E-620 Canon EOS 500D
Nikon D5000 Panasonic LX3

Panasonic GF1 Olympus E-P1
Olympus E-620 Canon EOS 500D
Nikon D5000 Panasonic LX3

Panasonic GF1 Olympus E-P1
Olympus E-620 Canon EOS 500D
Nikon D5000 Panasonic LX3

Measurable results

Camera Measurement
Panasonic GF1 Horizontal LPH 2450  3500 
Vertical LPH 2400  3400 
Olympus E-P1 Horizontal LPH 2300  2900 
Vertical LPH 2400  2700 
Canon EOS 500D Horizontal LPH 2400  * 3400 
Vertical LPH 2350  * 3350 
Nikon D5000 Horizontal LPH 2350  * 3050 
Vertical LPH 2350  * 3050 
Olympus E-620 Horizontal LPH 2250  * 2650 
Vertical LPH 2250  * 2650 
Panasonic LX3 Horizontal LPH 1900  * 2400 
Vertical LPH 1850  * 3200 

* Moire is visible
+ Chart maximum
LPH Lines per Picture Height (to allow for different aspect ratios the measurement is the same for horizontal and vertical)
Absolute resolution Point at which all lines of a resolution bar are still visible and defined, beyond this resolution loss of detail occurs (below Nyquist frequency).
Extinction resolution Detail beyond camera's definition (becomes aliased)

All the cameras see a significant resolution boost when switching to raw capture and - as we've seen with previous Panasonic SLRs - the GF1 gains the most, even using Adobe Camera Raw (which is rarely the raw converter that gives the highest resolution). It certainly seems that if you want to get the most out of the GF1 you can't rely on JPEG.

With most raw converters (including ACR and Capture One) you get significantly more resolution out of the GF1 than you do out of the Olympus E-P1, though using DCRaw (probably the most 'neutral' of all raw converters) reveals that the difference in absolute resolution between the two cameras is small - the GF1 appears to have a marginally lighter anti alias filter, but you need to be looking very close to see it.