canon extender calibration

[KIPAX]

On the basis that theres no such thing as a stupid question .. <gulp>

I have a 1.4tc and a x2tc .. am not happy with the results using 1dmkIV and L glass such as the new 70-200mkII

Can extenders be calibrated? or do we have to self calibrate the camera to the extender?

 

[MatBin]

I thought you had to mount it on a lens (the one you intend to use it on) and calibarate that combo. Not sure if that means the calibaration for the solo lens gets overwritten though.

Matt

 

[KIPAX]

I thought you had to mount it on a lens (the one you intend to use it on) and calibarate that combo. Not sure if that means the calibaration for the solo lens gets overwritten though.

Matt

Canon in camera calibration knows the difference between lens or lens+tc and will save diff calibrations... But having had my camera and lens calibrated at canon and no need for in camera calibration i didnt want to use that..

Thus a calibrated lens can be effected by the TC but do you fix in camera or can the tc be calibrated....at canon say..

 

[Canon Bob]

Tony,

Lens calibration is performed by adjusting a value within the lens (either a soldered link or software offset) to achieve the "BFCV" (Best focus correction value). This option isn't available in the Extenders as there's no movement to correct. It's theoreticaly possible to adjust the lens to match the extender but then the lens without the extender could be wrong and it's very likely that your two extenders would require a different offset.
I suggest that using the MA adjustment table is the less fraught solution.....not entirely fraughtless though.

Bob

 

[KIPAX]

Tony,

Lens calibration is performed by adjusting a value within the lens (either a soldered link or software offset) to achieve the "BFCV" (Best focus correction value). This option isn't available in the Extenders as there's no movement to correct. It's theoreticaly possible to adjust the lens to match the extender but then the lens without the extender could be wrong and it's very likely that your two extenders would require a different offset.
I suggest that using the MA adjustment table is the less fraught solution.....not entirely fraughtless though.

Its what I thought at the back of my mind (altough i didnt know the ins and outs) ..always best to ask though ... damm will ahve to try MA ..its a real pain.. shouldn't be too bad with the 400.. primes are easier..

THANKS