The Imaging Resource review says "Low to moderate, minimal effect on
images at edges, good results for a long zoom", so you are right,
it's less of an issue "for a long zoom". However, the FZ50 range is
the 35-420 mm equivalent - the S100FS goes down to 28mm equivalent.
CA is generally an issue at the wide end, not telephoto.
From page 17 of the DPReview:
"Unfortunately, from 200mm equiv. onwards, blue/yellow CA takes off spectacularly. It proceeds to get worse all the way up to the lens's extreme at 400mm."
Many have reported terrible CA at 18mm ... and that's the better of the two ends apparently. Again ... maybe sample variation has something to do with that.
If it was possible to produce an optically acceptable 28-400mm zoom
lens, why wouldn't all SLRs come with one?
Have you counted the mega zooms out there lately? Nikon 18-200VR, Canon 18-200IS, Ramron 18-200, Tamron 18-250, Tamron 18-270VC, Sigma 18-125, Sigma 18-200, Sigma 18-200OS ... there might even be more ...
And remember to factor in the crop factor ... these lenses reach to 300 or 400, more or less matching the S100fs for reach.
The widest zoom available
for many SLRs goes from 18-250, and many (most?) SLR users regard
that sort of lens as not much more than a toy for snapshooters.
Many (most?) people who say that do so from a lack of education. Opinions from forum trolls usually swing widely on either side of the truth ... with the worst coming from "born again" people who just bought their first quality prime, or noobs who want to appear knowledgeable but manage to convey naivety instead. Opinions from professional photographers are a more reliable indicator as to how good or bad these lenses are.
Thom Hogan likes the Nikon lense ... acknowledging its role as jack-of-all-trades, yet closing his review with comments like:
"Price/Performance winner. This is a far better lens than you'll ever expect, even for US$750. Far better. Good enough that it has replaced both my 18-70mm and 24-120mm as the walk around lens of choice for when I want to go light and with one lens."
And Bjorn Rorslett rates the Nikon lense at 4-, which is just at the level where you can produce professional quality images. The lense can do it, but not at all focal lengths and apertures. You must pay real money for that privilege.
Now ... what does that say about the 28-400 lense on this bridge cam? Nothing.
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