[IgorZ]

Very true, there was a review of the Sigma 100-300mm APO EX DG posted a few years ago that gave it the lowest rating in every area of IQ, with the reviewer declaring the lens the worst lens he had ever owned. While every other review, including my own, was distinctly positive.



Have you ever correlated that with sample size? if you did, you would most likely would find that the telephoto lenses perform on par with everything else.

Sample size or price? These telephotos are mighty expensive...

[Digitalis]

Sample size or price? These telephotos are mighty expensive...

prices can be artificially inflated - Especially true on the second hand market where there was an issue with the Assembled [AIV] Vs Made in Japan [MIJ] FA limiteds - commanding a higher price due to their origins, There is no detectable difference! The Sigma 100-300mm APO EX DG version commands a price premium even though it and the older APO EX version are optically identical - only a slight change to the coatings to EX version of the lens which makes at most a rather minor improvement to flare resistance.

[cyberjunkie]

- it's much, much better than expected for the $500 paid... but compared to a $2,000 Zeiss, it may well be unexceptional, so does it still deserve the 10 rating? If so, how do we use the ratings to choose between the $500 and $5000 lens?

I didn't post many reviews, but whent I did I always tried to give relative votes, not absolute.
I think it makes sense to compare a lens with others of similar characteristics, focal and coverage, and evaluate it considering the price.
Votes are quite high, if we exclude the occasional disgruntled fellow who owns a defective optic and thinks that all the others must be the same
Considering that, if I find a late FA zoom with plastic mount that performs much better than expected, even on digital full frame, should I give it a 6, comparing it to a DFA, or a 8, even 9, considering the very high price/performance ratio?
I think the latter is the right choice.
It would be a good idea to explain the rationale behind the rating in the text, so that it's not just a number...