Panasonic Lumix G Vario 45-200mm f/4-5.6 OIS - Review / Test Report - Analysis
Lens Reviews -
Wednesday, 18 February 2009 09:00
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Micro-4/3 files - both RAW as well as JPEGs - are automatically corrected either in the camera (JPEG) or in RAW converters (like Silkypix or Adobe Camera RAW). Therefore we decided not provide any figures here because they would show next to no distortion. However, the worst amount of uncorrected distortion is less than 1% so this issue is nothing to worry about anyway.
The 45-200mm G shows a fairly strong degree of vignetting at wide open aperture - at around ~1EV the issue will be visible in some scenes. The problem dissolves when stopping down by 1 f-stop. Interestingly the aspect is not auto-corrected in Adobe Camera RAW so it depends on the specific lens.
The lens produced very good albeit not really great resolution figures throughout the range. There's a slight drop in performance at the long range with a little contrast weakness at max. aperture.
Below is a simplified summary of the formal findings. The chart shows line widths
per picture height (LW/PH) which can be taken as a measure for sharpness.
If you want to know more about the MTF50 figures you may check out the corresponding
Chromatic Aberrations (CAs)
Lateral chromatic aberrations (color shadows at harsh contrast transitions) are heavily auto-corrected specifically at the long end. The non-corrected RAWs have CA peaks way beyond 2px at the image borders at 200mm. As you may notice belong the problem is very much reduced after the auto-correction. Interestingly most of the correction is done on the red-cyan CA variant whereas some blue fringing remains.