We wanted to offer just a bit more background for our IR news readers, along with some links to background info on how we do our IS testing, and how to read the results.
It was certainly a long slog getting here, but after almost two years of development, we're finally publishing our first quantitative Image Stabilization review, of the excellent Canon EF 70-200mm f/4L IS USM lens.
The rather extreme statistical nature of image stabilization performance led us on a long, arduous path, as we worked to quantify the performance of different IS systems. Now, after a bit more than 22 months of testing and analysis, we've finally arrived at a level of consistency and accuracy in our results that we're satisfied with, and that we feel will form a solid basis for comparing the effectiveness of various systems.
The full details of how we test is far beyond what I could fit into a news item, but does deserve a detailed description: Consistent with our policy of openness regarding our test methodologies, I've written an extensive White Paper about our test and analysis procedures. There's also a Reader's Guide to Interpreting IS Test Results that will help the average reader understand what our tests are saying.
Having worked with roughly 25 different IS systems over the last two years of development, we've been a little surprised at just how wide a range of performance we've seen, and also at just how much difference the photographer makes in IS system effectiveness: Relatively steady and shaky shooters will often have rather different experiences with IS systems. For this reason, we measure performance with two very different shooters, and also indicate how they did relative to the standard "1 over the focal length" rule of thumb for a "safe" shooting speed. - This will let our readers determine where their experience with a given IS system might fall.
As noted, a full discussion of the ins and outs of IS testing is way beyond the scope of this news item; we refer interested (ultra techie) readers to our Image Stabilization Testing White Paper.
For those who want to just cut to the chase, check out our Canon 70-200mm f/4L IS USM Image Stabilization Test Report, to see just what sort of real-world, measured shake reduction we found with it.
Stay tuned, we'll be rolling out more IS test results on SLRgear.com in the coming weeks and months. They typically take even longer than our standard lens tests to perform, as an adequate characterization of a lens or camera body typically requires many hundreds of hand-held test shots, and quite a bit of data reduction. We think readers will be happy with the results, though, as this is the first (to our knowledge) series of comparative, quantitative IS tests performed using an open methodology available anywhere on the 'net!
(Comments? Questions? We've also set up an IS Testing Discussion Thread on the SLRgear forums that I'll try to monitor and respond to over the next several days.)