I think I am slowly getting itSo what I should be looking at are S10 and M10 on both the Nikon and Tamron Charts they are of course not quite apples to apples since Nikon just says wide and tele which I guess would be 70 and 200 mm while the Tamron is 35mm, 85 and 150.
For what I used both for indoors at church they both performed very well but the need for the 35-50 mm area was what had me using the Z24-120 along with the Z70-200 so juggling two cameras and lenses on the go between the upstairs loft and the floor level. The Z70-200 images were mostly at 150 - 200 mm and are excellent and the charts show that.
But I can not tell any practical difference in the 85-120 mm area in the images I took but they were not at the same time in the same exact light etc.. And the Tamron is better than the Nikon 24-120 down in the 35 - 50 range as I would expect. So the one lens "workhorse solution" won out for my needs but would not for others.
I will post some of the bird ID images from my first birding outing with the Z600 f/6.3 on the forum in a moment.
This is when charts don't matter. Pick the lens that gives you the best results. Most modern lenses will give you outstanding images in "general" situations and other factors like weight and range and price are more important.
For architecture, you need the best MTF money buys because you need to utilize the entire frame and the corners are critical. Portraits, not that important, but other factors that aren't captured by the MTF are (oof falloff, microcontrast, 3d pop, etc.).
The MTF on the 600 suggests it's perhaps the best 600 made from sharpness perspective, and for birding, you obviously need that. The entry level Canon 600/11 will not give you that, and you can guess it from looking at the charts without taking a single shot.
Not to appear as snob, but in my experience, the best predictor of IQ is price.
