1) download a focus test chart and read how to use it
2) bring your tripod and laptop as well to the shop
3) turn off IS/VR (if any) when shooting
4) view 100% on your laptop
what i do is rest my arms on the table like a tripod...and then shoot words on the box itself. or for the recently acquired 50 f/1.8II, i shot the calculator at an angle. found one copy backfocusing because everytime i shoot a particular button, the one behind it is in focus instead. i think this method words fine enough. what u guys think?
1) download a focus test chart and read how to use it
2) bring your tripod and laptop as well to the shop
3) turn off IS/VR (if any) when shooting
4) view 100% on your laptop
This is indeed the perfect way to do it...
But I will not do that, too much hassle and most shops don't like a customer like that.
you are customer.