Checking a recently serviced lens
So you have the 2nd one from the left.?
Though the lens can have been cleaned it has not been serviced in any image as good as new' sense of the word.
Sigma have been unable to service this lens for many a year.
As fro black spots I'd ask a bit more, If they were from teh EX coating coming adrift then no issue, If they were mould spot then the coating are wrecked and price should reflect this.
Your question re firmware....This lens work on all Pentax cameras past current and I dare say future FW update are really a preserve only sigma cannon fit and one or two Nikons.
The lens is very good optically identical to the DG variant but the DG has a rear coating on the back elements that may improve flare resistance.
I've not noticed any advantage in the DG model and suspect DG coating of more relevance for wide angle glass
Here is some examples on different bodies
I'm about to buy a Sigma 70-200 2.8 APO EX (no DG, no MACRO and no HSM), that is supposed to be the sharpest version of all.
The seller just sent it to clean the optics (there were a couple of black dots inside that wouldnt affect image quality, but he decided to clean it anyway)
What should i test? Could the sharpness be affected by the cleaning?
They're supposed to be a great store, so if the job is done right, the sharpness should be intact, right?
PS : Im from Brazil, so its important that i get the lens working on the first try, or else i'll be losing a lot of money to get i serviced again (there is no Pentax or Sigma support here)
EDIT : Also, what about the compatibility of this lens with my camera? Some people talked about rechipping process, etc...how can i test if the lens needs to be rechiped?
Just autofocusing, stopping down, etc?
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