How do you test a lens at a store?

[Rienzphotoz]

A Sniff test should be sufficient. :|

Not allowed! Jared Polin (Fro knows foto) has a patent on that move

[RLPhoto]

A Sniff test should be sufficient. :|

Not allowed! Jared Polin (Fro knows foto) has a patent on that move

The generic off-brand smell test should be an equal alternative. 

[East Wind Photography]

So the best test you could do in a camera store is to take a newspaper with you and some tape and tape it to the wall.  Take some shots with it in decent lighting and examine the print at 100%...check center as well as corners.  Look for blurry edges and color fringing.

For telephotos, you have to really go outside in the sunlight and shoot something that is fairly far away such as the railing on an apartment building or some other fine detail that has lots of vertical and horizontal lines.

Many places wont let you take the gear outside BUT you should convince them to go with you or leave your drivers license or some other valuable.  Many times it's all about the relationship you have with the shop.

Finally, always buy from a reputable dealer with a good return policy.  Many will take back equipment if you dont like it for any reason as long you keep the usage to a minimum and it's unsellable as new.  This gives you an opp to actually try it under your own test conditions.  Check the return policies carefully!!!

[Rienzphotoz]

Many places wont let you take the gear outside BUT you should convince them to go with you or leave your drivers license or some other valuable.

I've always wanted to go the B&H Super Store in NewYork ... I am not from the US of A, so I could pickup one of their most expensive L prime, give them my license on the last day of my US trip, take the lens out and make a dash for the airport  ... but first I need to practice running with heavy item, to build up my stamina, those darned L primes are really heavy ... before someone starts posting some nasty comments or reporting me to the moderator that a B&H thief is lurking around this forum, let me make it clear that I am joking.

[Rienzphotoz]

A Sniff test should be sufficient. :|

Not allowed! Jared Polin (Fro knows foto) has a patent on that move

The generic off-brand smell test should be an equal alternative. 

Ha ha ha ... good one.