i have had my 50 1.8 for over a year now and never use it because the focus is terribly inconsistent. i mean like 1 sharp image out of 30 even at f8. i wasn't overly disappointed because it only cost 80$ on sale and i know you get what you pay for. i have been doing a lot of reading instead of shooting because of the arctic temperatures we have been having for over a month , and found a few website where people have used the "solder trick" to fix their nifty fifty. i decided to give it a whirl since it is basically a disposable lens and i dont use it anyways. i started by popping the back cover off, its just clipped in. then found the contacts that need to be soldered together. this was the complicated part because none of the posts i read were clear about which contacts needed to be connected. they basically said try it and see what works. well i can tell you joining all the contacts like one guy said , doesnt work at all. the focus motor started making noise as soon as i connected the lens to the camera and it wasnt even turned on yet. then i tried the 2 contacts on the left together and the 2 on the right together. no funny noises , but it would not focus at all. it just kept hunting. then i tried just the 2 contacts on the right joined together and bingo ! focus is perfect 95% of the time versus around 10% before.
i have no idea what joining those contacts does , but it works great for me. its still a plastic cheapo lens but at least now i can use it with confidence.
now i wish i would warm up a little outside so i can start taking pics again instead of fiddling lol.
this is the back cover. very easy to pop out with just the tip of a sharp knife
IMG_1912 by sedwards679, on Flickr
these are the contacts i am talking about
IMG_1910 by sedwards679, on Flickr
and these are the 2 i joined together(blue arrow)
IMG_1910-2 by sedwards679, on Flickr