how to test a lens in shop.

[j.palmer]

well im nearly back in the game .

my newly aquired d300 and ive just got the good news on my part exchange with the rest of my canon mount lens and camera.

i had orded the 300mm af-s with tc.

but due to PC problems and othere stuff to bye ive had to cancel.

but placed the order for the bigmos .

now as im a veterun of the bigma 4years blood, sweat, tears.

is there any test shot i can due in shop. as ive heard about IQ and build, not sharp, noisy etc

but then you find some excellent shot and no complants :bonk:

seriouly with money being tight ill only have to pay about 240.00 for a new sigma 150-500 os .

many thanks j

 

[Luke_]

Take it and you should have a money back guarantee if its not up to par.

 

[Jamieconverge]

yep, as above or if you've got time take your camera body and take a few shots with it in/outside the shop, then view at home?

 

[StewartR]

Quick lens test: Pick a high-contrast target in good light at a reasonable distance - tens of metres. Things like estate agents boards are good. Take 4 photos, one with the target in each corner of the frame, and examine them on the camera's LCD. They should all be equally sharp. If they're not, it suggests that the lens is decentred, which is one of the most common faults.

 

[Danger_Mouse]

Sorry to thread hijack but thought it might be under the same part of advice?

I have just received my Sigma 70-200 2.8 EX (second hand) and i have noticed that it lets out a "squeak" when it is focusing. what could this be? should i be worried?

 

[mrtoad]

its a bit like checking out a musical instrument
first you have to play something and cant
or
you look at the build and workmanship of the item
if its a lens...i expect the qc at the factory takes care of that

test pics i suppose could be done quietly and methodically within a day or so at your own place or outside venues

doesnt the shop have to honour a 30day return guarantee and give a refund if you can show faults or failings

the tests i have seen for lenses usually are beyond what can be done in a poorly lit shop without a tripod etc and ways of blowing up the images

i would be interested to hear how you get on

cheers
geof

ps..the only failing i have had was a sticking diaphram which i could have checked out in the shop
as it happened...the photoshop returned the tamron to themselves and i got it completely overhauled...they also found a chip on the front element and replaced that
it was second hand of course..so i got a 'new' lens out of it