Well, time for an upgrade. But no definitive insights yet.
I'm currently doing a series of testshots the following way:
- nail testchart to the wall (my new DIN A3-sized one on photo-paper comes in handy here)
- stand back so that you're a good 10m or so away, handheld
- switch camera to S
hutter priority at 1/125sec
- zoom lens to 400mm
- take two series
of shoots, one with OS="on", one with OS="off"
- Take each series in sequences of three shots, put camera down between each sequence to relax your arm and shoulder, breath normal
- Take at least 9 shots within each series
After downloading the shots to the computer, I evaluate sharpness and classify it with 0-5 stars in Lightroom. 0 stars meaning totally cr*p, 5 starts meaning sharp, no blur to be seen. I'll give you some examples later.
With handholding I'm getting a distribution of images from 0 stars to 5 stars due to shake. The interesting point now is the following: If I use OS, is the distribution of the image quality of a series of shots more favourably skewed towards the sharp end in comparison to a series without using OS?
Well, you would normally expect that the OS will eliminate shake to a certain degree and thus see more sharp images in a series than without OS.
All I can tell you for now is that I get some strange statistics with this lens. In one series I definitely got a better IQ distribution with OS="off" than with OS="on"
But I'm shooting and reshooting again to make sure that this is not a one-off statistical hick-up.
But some things I can already tell for sure with this test set-up:
- When I handhold this >2kg lens+camera combo I can really see me shaking! So I need a OS/IS/VR that is working!
- sharpness variations from different apertures is not the critical point in this set-up.
- focus errors is also a non-issue here as the magnification is relatively low, due to the distance from the test-chart.
So what we'll be really seeing in this set-up is efficiency of OS/IS with this lens.
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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