ARRI Forum

Hi there:
My Alexa is not reading the master prime lenses info so I want to introduce de lenses via wcu-4 to an SD card and then pass it to the camera (Alexa xt).

Something is goin wrong with the card, first the wcu4 did not recorded the lenses, in the last step is goes off automatically, now it records the lens, I see it in the Edit lense screen of it but in the camera I cannot see it.

I did got one passed from wcu4 to Alexa xt in the equipment check but then we formatted the sd card and stopped working.

Is there a particular tree of folders that must be created in the sd?

Best regards
Saul Oliveira
AC
Spain

Hello Saul,

The WCU-4 will save any custom lens file in the folder ARRI/ALEXA/LDA and it will create this folder automatically.
If your camera does not recgonize your Master Prime lens automatically (maybe the LDS contacts are faulty?), you can select the corresponding lens file from the cameras Lens Data Archive (LDA). Make sure to select the correct scale class for your Master Prime.

Kind regards,
Hendrik

Where can I see that scale class indication in the lens?

I mean, I tried, but never know which scale to select

Best regards

Saul

Hello Saul,

The focus ring indicates a letter (for example N, L, ...) next to the engraved focal length. Select this letter after selecting the focal length in the Lens Data Archive.

regards,
Hendrik

Following on from this,

Some Lens classes from the LDA archive don't match up to the one's on the lens.

For example, the class on the lens is NN (double N) however on the LDA you can only choose N - Single N. (from memory)

Does this affect the mapping of the lens?

Hi,

the single letter, in this case N, on a scale ring denotes that it is in meters. The double letter codes like NN are the equivalent scale rings in feet, and therefore match perfectly.

There are meter lenses with 2 letters for example HJ, the feet scale would then be labeled HJHJ

Cheers
Silvan