How to choose the best copy when buying new lens?

[chalib]

Hi seniors

New to photography. Need advise on how to choose best copy when buying new lens in a shop? Any step or what things we need to check beside the physical condition?

TIA

[dragos]

just bought my lens at CP...what i do is, bring along your own cam.

check at the largest aperture...see if it is soft.

do focussing at various pts.

check if serial and warranty tallys.

[chalib]

Originally Posted by dragos just bought my lens at CP...what i do is, bring along your own cam. check at the largest aperture...see if it is soft. do focussing at various pts. check if serial and warranty tallys.

Thks for advise. 'do focussing at various points' means shooting object with different distance? with one point focus or multi point?

I read abt dust in the lens. How to check this?

[noob117]

i tot most of the time wide open is soft?
how u tell the diff of softness between glass or the fault of the manufacturing process?

[b-a-k]

ya lor, might as well reject the first lens the shop give you as they will try to sell of 'rejected' goods earlier??

[chalib]

Originally Posted by noob117 i tot most of the time wide open is soft? how u tell the diff of softness between glass or the fault of the manufacturing process?

[noob117]

Originally Posted by chalib

erm... when lens are wide open they are not as sharp as liek say F8.
so when it at it max aperture eg. 2.8 the image tents to be soft.

so how to tell apart this softness to softness of lens deflects

[tSkye]

It would be good if you could bring your tripod and notebook computer. Shoot tethered and view it off the screen. A general rough guide would be to compare between two lenses at a time by placing their image shot, side by side.

[chalib]

Originally Posted by tSkye It would be good if you could bring your tripod and notebook computer. Shoot tethered and view it off the screen. A general rough guide would be to compare between two lenses at a time by placing their image shot, side by side.

u mean we ask the shop to show 2 copies in a time and do comparison?

[SolBadGuy]

Originally Posted by chalib u mean we ask the shop to show 2 copies in a time and do comparison?

why not? as the consumer u do have the right to protect ur own interest. go to shops like MS, they will allow u to test till u're satisfied. but have to be reasonable also lah.