01-04-2015, 10:23 PM
Well, other "lens test" labs are to me also black boxes. They can explain what they are doing and maybe also how they do it - but after all, what counts is the advantage of a comparison of incomparable parts of systems. Like you mentioned, there are sometimes thinner or thicker glass elements in front of a sensor. Extremely thick on mirrorless µ4/3 system, like I learnt from lensrentals.
LenScore just says
Based on these findings, we've created a lens testing system based on a custom-built camera using a 200MP super high resolution CCD sensor, an apochromatic high-precision lens group custom-made by one of the world's best industrial optics manufacturers and 5 exchangeable lens mount adapters. The sensor of our measuring camera is very slow and not designed for low light applications, but these restrictions are of no significance when measuring the optical performance of a lens.
and
The most expensive part of our test bench is not the 200MP digital back, it's the custom-made apochromatic lens group. We neither have the expertise to calculate such a lens group nor are we able to manufacture one. Both tasks have been commissioned to a highly regarded Swiss industrial optics manufacturer. They did a very good job, but they are very expensive. To measure APS-C lenses, or lenses for any other sensor format, we'll need a corresponding lens group. Another investment of this magnitude is currently not an option.
To me, it's the same device for all lenses, hence the same flaws and only for full frame lenses. Question is, what are the flaws and do those matter much? Will an excellent lens become crap and a kit lens shines unexpectedly? DxO Mark is testing different cameras (also very time consuming) and some of us do criticize them for giving too good (or bad) results. Using interferometry does say, how good a lens is on interferometry - and each aspect more is some kind of conclusion which might be right or wrong for our purposes. Like I said, a lens is a bit more than only test results. And I'm not talking of a "creamy rendering of colors" or whatever voodoobabble the lens poetry of some, mostly German, producers is trying to create. <_<
LenScore just says
Based on these findings, we've created a lens testing system based on a custom-built camera using a 200MP super high resolution CCD sensor, an apochromatic high-precision lens group custom-made by one of the world's best industrial optics manufacturers and 5 exchangeable lens mount adapters. The sensor of our measuring camera is very slow and not designed for low light applications, but these restrictions are of no significance when measuring the optical performance of a lens.
and
The most expensive part of our test bench is not the 200MP digital back, it's the custom-made apochromatic lens group. We neither have the expertise to calculate such a lens group nor are we able to manufacture one. Both tasks have been commissioned to a highly regarded Swiss industrial optics manufacturer. They did a very good job, but they are very expensive. To measure APS-C lenses, or lenses for any other sensor format, we'll need a corresponding lens group. Another investment of this magnitude is currently not an option.
To me, it's the same device for all lenses, hence the same flaws and only for full frame lenses. Question is, what are the flaws and do those matter much? Will an excellent lens become crap and a kit lens shines unexpectedly? DxO Mark is testing different cameras (also very time consuming) and some of us do criticize them for giving too good (or bad) results. Using interferometry does say, how good a lens is on interferometry - and each aspect more is some kind of conclusion which might be right or wrong for our purposes. Like I said, a lens is a bit more than only test results. And I'm not talking of a "creamy rendering of colors" or whatever voodoobabble the lens poetry of some, mostly German, producers is trying to create. <_<