Originally posted by house Did you take focal length into account when comparing those hundreds of charts? To me it sounds, based on your observations, that you didn't? You don't buy a uwa prime for bokeh. Lens rentals have confirmed that zooms may be good in the center but never match primes at the corners and suffer more from sample variation.
You have the link?.. I'd go along with zooms don't match primes at every focal length. But a lot of zooms do at one particular focal length or range, and everything else is gravy.
I've compared my DA*60-250 to a 90mm and Tamron 90, a highly respected lens on all formats. The images were indistinguishable unless, you really squinted, there were slight difference in micro-contrast.. So straight up, I've tested your theory, and it came up wanting in the real world. I'm quite happy to accept that on a test chart you might be fooled by insignificant differences. One number is better than the others, it has to be better right. In fact my biggest quarrel with test charts would be, until it's established what a significant difference is for an average viewer, they are pretty much meaningless. My guess is it the point is somewhere above 100 lw/ph and less than 200 lw/ph, but, I've never seen it confirmed in any way.
And another thing I've noticed, test chart sharpness does not always translate into the best rendering. You can say one lens is test chart sharper, that doesn't automatically translate into better images. The size of the print and viewing media matters.
There are situations where I will happily shoot with my FA 35-80 I paid $79 for. If the size is going to be reduced and you're viewing on a TV monitor it renders beautifully. And in a 7 lens forum comparison almost 30% voted for it as their favourite 35mm, ahead of the DA 35 2.4 and many others that technically are rated much sharper, almost 30% of the forum voted for it, 50% more than you would expect from random selection. That is well above standard deviation. For reduced sized rendering it was the best of the 7 lenses tested.
Basically, the more experience you have, the more you rely on your experience with a particular lens, understanding what each lens has for it's strength and the less you rely on test charts. Another example would be the 21 ltd. Not a test chart favourite, terrible in high contrast situations, but if you know where to use it, low key mellow pastel type images, it produces stunning results. You can't tell that from a test chart.
Last edited by normhead; 01-28-2020 at 03:47 PM.