What's the big idea about lens calibration?

[mace1980]

Hi,
Can some pro out there enlighten me on this?
I mean, I keep seeing posts saying that their lens become sharper after calibration.
So what exactly happens during calibration that makes the lens better?
Must the camera be brought along for calibration?
Pardon me if it sounds noobish.
Thanks.

 

[mace1980]

Any views? :gbounce:

 

[satay16]

you see, bad lenses are called lemons.

lemons are lenses that suffers problems like high CA, back focusing, front focusing, etc.



calibration is mainly for lenses with BF focusing issues(back & front). so what calibration does, is that they rechip the lens, so that it no longer focus wrongly. with a more accurate focus, the lens takes sharper images.

 

[scenar]

calibration is mainly for lenses with BF focusing issues(back & front). so what calibration does, is that they rechip the lens, so that it no longer focus wrongly. with a more accurate focus, the lens takes sharper images.

Not entirely true. Some lenses have chips which can be reprogrammed, hence re-chipping is not needed.

Just to add: lens calibration is more often done for 3rd party lenses: i.e. sigma.
heck, just got my sigma 120-300 calibrated. yet to test it out though.

 

[satay16]

Not entirely true. Some lenses have chips which can be reprogrammed, hence re-chipping is not needed.

Just to add: lens calibration is more often done for 3rd party lenses: i.e. sigma.
heck, just got my sigma 120-300 calibrated. yet to test it out though.

hmm.....weird. i always thought chips are like CDRs. one time write only.:bsmilie:

 

[scenar]

hmm.....weird. i always thought chips are like CDRs. one time write only.:bsmilie:

no lah! got NVRAM mah. your motherboard cmos also can be "flashed" i.e. reprogrammed. firmware in the cam can also be upgraded , i.e. "re-written"

remember all the firmware updates for 20D 1dmk2, d2x, d80, watever else....

 

[satay16]

no lah! got NVRAM mah. your motherboard cmos also can be "flashed" i.e. reprogrammed. firmware in the cam can also be upgraded , i.e. "re-written"

remember all the firmware updates for 20D 1dmk2, d2x, d80, watever else....

yeah. *nod nod*. though you missed out the 7D. so sad.:cry:

 

[mace1980]

oh... so its no point calibrating my 24-70 f/4L and 400D at canon sg?

 

[scenar]

oh... so its no point calibrating my 24-70 f/4L and 400D at canon sg?

if it ain't broke, dun fix it...

why bother with all this if your lens n cam is working fine?

 

[jay9526]

sorry to OT, but how to check for front and back focusing problem?

 

[scenar]

http://www.google.com.sg/search?q=f...s=org.mozilla:en-US:official&client=firefox-a

many results there. u can use the one for the d70, not a problem.