Panasonic GM5 Review Part 2 Picture Quality and Performance
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| GM5 with 15mm f1.7 at f4. top and bottom cropped. Very high resolution hand held. |
Although the GM5 is diminutive it has a standard 17.3 x 13 mm Micro Four Thirds sensor and technical image quality in about the middle range of recent 16 Mpx M43 cameras.
With a good lens mounted it can deliver some quite impressive results revealing a great deal of fine detail in a scene.
Highlight and shadow detail are about average for a M43 camera. However with a little care at the exposure stage and RAW capture it is possible to reveal good highlight and shadow detail even with subjects having very high brightness range without resorting to multi exposure HDR strategies.
Dark tones can be lifted in Adobe Camera Raw (or Lightroom) without destructive effect on image quality other than a modest increase in grain. This allows the photographer to apply a little negative exposure compensation to prevent blown out highlights then lift the dark tones for a pleasing overall result.
I ran a RAW stress test. This consists of taking one photo of a test subject with ISO 6400 set on the camera and another photo of the same subject with ISO 200 set but underexposed 5 stops (giving the same aperture and shutter speed) then pulled up 5 stops with the Exposure slider in Photoshop Camera Raw.
The 5 stop pulled version showed mild yellow color cast and a little more grain than the ISO 6400 version. There was some ‘picket fencing’ on the histogram in the dark tones and some loss of detail in the deep shadows. This test shows that dark parts of an image can be pulled up without serious adverse effect on picture quality.
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| GM5 with 15mm f1.7. Good work against the light with truckloads of resolution. |
RAW files with suitable editing in Adobe Camera Raw look good to my eyes up to about ISO 3200 or even 6400 if necessary.
JPGs look clear and sharp without any smearing or watercolour effect up to about ISO 1600. I use the following Photo Style settings: Contrast -2, Sharpness +1, Noise Reduction -5, Saturation 0.
With a fast prime lens mounted the GM5 can make pictures of very good quality without flash even indoors in low light.
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| Very high subject brightness range. The sky was very bright. Exposure minus 0.66 stops, adjustments in Adobe Camera Raw. Good detail throughout. |
Auto Panoramas
The GM5 has an auto panorama feature accessed via a dedicated position on the Mode Dial. I tried it with the 12-32mm kit zoom and the 15mm f1.7 prime. Results are dependent on subject selection, lighting and user technique. Straight horizontal or diagonal lines are not managed well, being subject to ‘jaggies’. Subject elements close to the camera may not stitch well.
However with appropriate subject selection, practice and good technique extremely impressive results can be achieved, with no stitching faults, very high levels of detail and good shadow/highlight rendition.
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| In camera auto panorama. Good highlight and shadow detail, huge amounts of detail, clean stitching. |
Performance
Overall the camera operates quickly, responding without delay to user inputs. You can make adjustments with the buttons and dials while the camera is writing files to the card.
Single autofocus is almost instantaneous with many lenses including the 15mm f1.7 and the 12-32mm kit zoom.
Looking at the two thousand or so test shots I have made thus far of static subjects I see nil misfocussed frames. Nil. Single AF is not only fast it is very sensitive, accurate and reliable.
It will focus on brush marks in paint and the fine texture of a carpet.
It works even in light levels so low one can hardly see anything. The camera then switches to ‘low light’ focus mode which is slower but very accurate. The focus assist lamp is not required.
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| Veiling flare. The sun is just outside the top right corner of the frame. I turned the camera 45 degrees to the right and the flare disappeared. |
Shot to shot time with Single shot drive, AFS, RAW or RAW+JPG capture and AF plus AE on every shot is 0.6 seconds.
The GM5 is not ideal for sport/action but it might be used for capturing subjects such as children at play. In this situation the very fast AFS will usually deliver a correctly focussed result.
In Burst Mode M with the mechanical shutter (AF and live view on each frame), the buffer will allow 7 RAW shots at 3 frames per second or 23 Fine JPGs before the frame rate slows abruptly. With a 40 MB/sec card the buffer takes 16 seconds to clear.
In Burst Mode M with the E-Shutter and AF+ live view on each frame the frame rate increases to 7 fps, again allowing 7 RAW or 23 JPG Fine shots before the frame rate slows.
Manual focus works very well with peaking and picture-in-picture auto zoom especially with one of the fast primes which give a very clear in focus/out of focus indication. Anyone coming from an entry level DSLR will be astounded at the speed and accuracy with which manual focus can be achieved with this camera (and other current model M43 cameras with peaking).
I found exposures with Multiple Metering Mode reliably accurate in most situations although exposure compensation is required with very light or very dark subjects.
The camera has user adjustable Zebras which allow accurate pre-exposure evaluation of highlight exposure and guide Exposure Compensation when required.
