---
title: Cooke /i
slug: ncam-reality/cooke-i
createdAt: 2021-09-16T02:14:06.000Z
---

## Overview

Ncam Reality can read lens metadata from a /I lens equipped lens.  The reading of data is via an Ncam provided serial cable that connects to the 4 pin lemo port on the body of the lens

:::hint{type="warning"}
Please contact Support\@Ncam-tech.com if intending to use /i data, the initial mapping process requires some assistance
:::

### Required Parts

Ncam provided /i serial cable

/i lens featuring a 4 pin lemo connector

::Image[]{src="https://api.archbee.com/api/optimize/Qn0sdcVrDcDbwMFmH0oYn/JeZT-6HjYEnwdrzL84ZhA_lens-i-and-xd-port-4pin-lemo-m-to-7pin-lemo-m.jpg" size="58" width="4000" height="4000" position="center" showCaption="false"}

### Compatibility

The /i protocol is only available on the Mk2 platform

### Instructions

Inside the preferences of the Ncam Reality Full UI set the encoder type to "**Cooke /i & Zeiss eXtended data**"

Connect the Ncam /i cable to the **RS232 **port of the Mk2 server or connection box, connect the 4 pin end to the /i port on the lens body

## Encoder Mapping

Currently the encoder mapping process when using /i lenses requires the use of Mk2 external encoders for the initial setup, the process is described below and requires the use of external encoders for the initial mapping.

Please contact Support\@ncam-tech.com for help and assistance with the /i mapping process if required

### Introduction

Ncam Reality requires ***Normalised*** lens encoder values. Unfortunately, they are not always available as part of the /i or eXtended Data.

As a result, it is necessary to do a one time, per lens, mapping procedure to be able to map absolute /i values to those of another set of encoders which do provide what is needed. Namely, Mk2 encoders.

:::hint{type="danger"}
***As a fallback option, a generic mapping table is provided for a focus in the range of 807mm to infinity. ***

***That being said, all focus distances closer than 807mm will all be reported as 0 from the encoder.***
:::

:::hint{type="danger"}
***When using a Connection box, the following steps need to be conducted on it and not on the Mk2 server. ***
:::

### Hardware prerequisites

- Ncam branded /i RS232 cable
- Mk2 external encoders

### What is the mapping procedure?

To map a Cooke /i compatible lens to an external encoder, please follow these simple steps:	

- All encoder motors need to be turned OFF to allow the lens barrels to be freely manipulated during the process.
- Ensure the Mk2 external encoders have been rigidly mounted before starting this procedure.
- The Mk2 encoders need to be connected to the UART port on the box and the /i lens to the RS232 port.
- Connect to the MK2 Server or Connection Box remotely through SSH or open a terminal when using VNC.
- Type in the command: `sudo map_cooke`
- Follow the instructions on screen.
- Once finished, the CameraBarDaemon service should have been restarted automatically.
- In Ncam-Reality, you need to ensure the type of lens encoder being used is Cooke /i.

### Where is the mapping file located/read from?

On the box where the mapping has been done, a file named after the lens model will be created at:		

*`/opt/Ncam-Tech/CameraBarDaemon/calibrations/mappings/lensname.csv`*

If the mapping is restarted and completed for the same lens model, the file will be overwritten.