Originally posted by TedW Not to change the subject but I would be curious as to what legacy lenses are we talking that give the great results.
for pentax legacy glass, 28mm to about 35mm can be magic... my favorite for landscapes is the m28/3.5, here is an unprocessed ooc jpeg example on the a7r, blow it up to 100% and pixel peep the sides and corners:
https://www.dropbox.com/sc/4axj2t2btcq46ia/AAAYjnpTXjkL_K9ngU3T40aea
ugly bokeh, but do you really need bokeh on a 28mm lens... the pentax-m series wide lenses deliver in the corners, while the wide taks are weaker there, but sometimes stronger across the middle 2/3rds of the frame.
for example, the pentax-m35/2.8 is a low contrast lens, as proven with focus peaking, but it's better in the corners than my super tak 35/3.5; however the latter absolutely pops in that middle 2/3rds of the frame... different horses for different courses.
at 50mm, all three of my takumars never sharpen up fully in the corners, so for landscapes the more modern k-mount is probably the way to go:
50mm prime lens comparison, shot on Sony a7R, first round
---------- Post added 06-04-16 at 08:40 AM ----------
Originally posted by bxf Just for my education: why would any lens perform better on FF than on APS-c? Or am I misinterpreting the discussion?
i don't know that people were talking ff vs. crop, but the answer is that the more pixels you can put in a photo, the higher the resolution will be... flip side is, more pixels will show defects much more clearly.
the struggle with camera lenses is always at wider focal lengths; by the time you hit 100-135mm, they all tend to be clean across the frame.