As of April 2024 all lens tables must be built on the LDT-R2. Tables for the LDT-A2 and LDT-M2 can be exported from the LDT-R2 unit so a WCU-4 or Hi-5 is no longer required.
If you have rented the LDT-A2 or LDT-M2 and were not provided with an LDT-R2 (or similar) to build lens tables, please contact your rental house.
¶ Introduction
Creating a lens table is essential to the encoding process. It requires inputting the relevant lens information (lens name, brand, serial number etc.) and then inputting all of the marks from the axis’ (focus/iris/zoom) for each lens. The following guide explains this process.
This guide is focused on the lens mapping process. Lens maps can be created on the LDT-R2, LDT-V Series and LDT-F1 units. This guide applies to all of these units, but will primarily refer to the LDT-R2.
If using the data injection method for RED, DXL or Venice, then it is recommended that you fully set up the camera to test data injection while mapping.
If mapping for use with an LDT-A2 or LDT-M2, the camera settings are only necessary when using those units after maps have been created. Maps built with this LDT-R2 setup will be converted and imported to the Alexa camera.
¶ Setting up the LDT-R2
Creating maps for each lens requires powering the unit and pulling data from the relevant motor control system.
¶ LDT-R2 Rigging
Power the LDT via the PWR port with either the PWRA, RUNA, PWRC, PWRD cables.
¶ For Preston
Connect the MDR to the LDT-R2’s MDR port with the MDRP (blue) cable,
¶ For LCUBE
Connect the LCUBE Serial port to the LDT-R2 MDR port with the CML (blue) cable,
The LCUBE must be connected at the end of the motor chain.
¶ For CMotion Camin
Connect the Camin Serial port to the LDT-R2 MDR port with the CM (orange) cable,
¶ For Tilta
Connect the Nucleus-M to the LDT-R2 MDR port with the TNM (Blue) cable.
¶ Setting up the LDT-R2
Push in the joystick to enter the menu, and use the back button to go back.
¶ For Preston
Choose: Menu > Settings > Advanced > Data source > Local Table
¶ For LCUBE
Choose: Menu > Settings > Advanced > Data source > Pull from LCUBE
¶ For CMotion Camin
Choose: Menu > Settings > Advanced > Data source > Pull from Camin
¶ For Tilta
Choose: Menu > Settings > Advanced > Data source > Pull from Nucleus-M
Additional information about the LDT-R2 unit can be found in the designated unit guide here.
¶ Lens Control Systems
The LDT-A2 and LDT-M2 units are only compatible with the Preston system. If building maps are to be used with either unit, the mapping LDT-R2 needs to be using the Preston system.
The LDT-R2, LDT-F1 and LDT-V Series have additional lens control compatibility options.
If different lens control systems are being used across a show, maps should be made for each different system.
For example, if a show is using both Preston and Tilta Nucleus-M, each lens will require one map per lens control system.
¶ Setting up the Preston MDR and Hand Unit
It is essential that all Preston MDR and HU firmware is updated before any lens tables or F-Maps are built.
MDR firmware can be checked by saving a config on the LDT-R2.
Choose: Menu > Save Config
The MDR must be connected before saving.
Once saved, the file can be viewed on the MicroSD card. The MDR firmware is listed at the bottom.
Lens maps must be created using the natural direction of the Preston handset.
On the LDT display, infinity should be on the left of the map for focus mapping. For iris, wide open would be on the right.
Mapped lens files can be edited at a later time, allowing each axis to be flipped without needing to be remapped.
¶ Setting up the Tilta Nucleus-M
¶ Connecting Tilta Nucleus-M to the LDT-R2
Please ensure the handset it running the latest available firmware
- Connect the Nucleus-M to the LDT-R2 MDR port with the TNM (Blue) cable
¶ Setting up the LDT-R2
Push the joystick in to enter the menu, use the back button to go back.
- Choose:
Menu > Settings > Advanced > Data source > Pull from Nucleus-M
The motors must then be linked to the correct FIZ axis.
- Choose:
Menu > Motor/LDE setup > Focus - Choose:
Menu > Motor/LDE setup > Iris - Choose:
Menu > Motor/LDE setup > Zoom
From here MOT 1 - MOT 4 can be selected in accordance with the motor mapping that is set on the Nucleus-M controller.
The motor direction can be set to normal or reverse if required.
¶ Serial Loop Through for 3rd Party Devices
If no serial port is available on the MDR, the LDT-R2 has a serial loop through port to connect 3rd party devices. Connect the 3rd party device to the serial port of the LDT-R2 and ensure loop through is enabled:
- Choose:
Menu > Settings > SERIAL port > MDR LOOP
There is a known issue between the CineRT and LDT-R2 where data will not show up when connected. If this happens, check the CineRT is set to
Serial Out > MDR. If this does not resolve the issue, connect everything up as normal then power cycle the LDT-R2.
¶ Using a Light Ranger with any LDT
The LDT does not fully support serial passthrough for the Light Ranger.
If the user intends to use the Light Ranger, they can do so by connecting to the serial port of a compatible MDR-3.
At present, DCS does not fully support the Light Ranger through the LDT's serial port.
If required, then it is recommended that this setup is fully tested before production begins, to detect any compatibility issues with the user’s setup.
¶ Auto Lens Select Feature
This feature is unavailable for the LDT-A2 and LDT-M2.
The LDT-R2 supports ‘auto lens select’ on the HU3 and HU4.
If enabled, the LDT-R2 will automatically select the same lens map that the Preston Hand Unit is using.
To use this feature, F-Maps must be created prior to building maps on the LDT.
With the correct F-Map loaded, the name and serial will automatically appear on the LDT when choosing ‘Add Lens’.
Accepting this information will auto-populate key lens information such as lens brand, lens name, lens type, focal length and serial number. This information will allow ‘auto lens select’ to be used after creation.
All F–Maps must be made on one hand unit and shared with other units. LDT maps should be built on the same hand units as the F-Maps.
If a production is using a mix of HU3 and HU4, it is recommended that F-Maps are made on the HU4 and shared from there. This allows for maximum F-Map accuracy and compatibility.
There is a known issue where ‘auto lens select’ will not work unless the Preston units are updated.
¶ Programming a New Lens Table
¶ Lens Table General Settings
Before creating the first lens table, please review and adjust the following settings accordingly.
¶ Data Source
Data source should always be set to ‘Local Table’ when using the Preston lens control system.
This can be found in Settings > Advanced > Data Source > Local Table
¶ Using Auto Lens Select and F-Map
The LDT-R2 offers two modes tailored to the focus puller's requirements that can be loaded during the day and encoded in the unit. These modes determine the encoding process and the unit's interaction with the LDT-R2.
Enabling Auto Lens Select allows for seamless operation, as the LDT-R2 automatically updates its selected lens map whenever an F-Map change occurs on the Preston Hand Unit. F-Maps must have been created before the LDT mapping, and the information is used when creating a new lens file on the LDT.
If F-mapping isn't required for a particular shot, it can be promptly disabled after loading the lens. The selected lens will remain loaded on the LDT-R2 until a new lens is chosen on the Preston HU.
During lens mapping, the LDT-R2 selectively extracts certain lens details from the F-Map, including brand, focal length, serial number, lens name, and type. Since the LDT unit constructs accurate lens tables, it's sufficient for the F-Map's lens tables to only be partially completed. This will allow the user to skip filling in the initial lens information on the LDT-R2.
If an F-Map is not loaded before the creation of a new lens table on the LDT-R2, the lens brand, name, type, focal length, and serial number must be manually entered. Whenever a lens change occurs on the camera, it's essential to manually select the new lens on the LDT-R2.
¶ F-Mapping Recommended Workflow
To ensure that Auto Lens Select works on all devices when using multiple cameras follow this workflow:
It is recommended at the beginning of each new job that all F-Maps are cleared from the Preston Hand Unit to avoid duplicating lenses.
F-Map all lenses on one Preston Hand Unit (it is recommended that a HU4 is used for the main set of F-maps if available),
Share these maps to all other handsets using the Preston Bluetooth Module via the Preston App (visit the Preston website for more info).
¶ Adding a New Lens When Using F-Maps
Save all F-Maps to the "Other > User" folder to ensure auto lens select feature works across all MDR units.
Turn on Auto Lens Select
- Choose: 'Menu > Settings > Auto Lens Select > On'
Mount a new lens to the camera. On the Preston MDR press the calibrate button.
This will calibrate the LDT-R2 as well. Once calibration finishes, on the Preston HU3 or HU4, create a new F-Map of the lens attached to the camera.
If the lens has already been F-Mapped, select it on the Preston HU. In the LDT-R2 menu:
Choose: Menu > Add Lens
The LDT-R2 will display a message with the name of the lens. If the lens name matches the lens mounted on the camera and the one loaded on the Preston HU3/HU4.
Press ACCEPT to proceed.
IMAGE: COOKE S4
Lens details such as Brand, Type and Serial Number will auto-populate. This allows the user to jump directly to the FIZ mapping stage.
¶ Adding a New Lens When Not Using F-maps
Please be aware that the HU prompt may display inaccurate lens names and serial numbers, even with auto lens select and F-mapping disabled. If you encounter a situation where a lens name is inaccurately provided while adding a lens on the LDT-R2, select the 'other' option and manually input the correct details.
Turn off Auto Lens Select
Choose: Menu > Settings > Auto Lens Select > Off
Turn off F-maps on the Preston HU3/HU4
Mount a new lens to the camera and calibrate:
If using the Preston MDR press the calibrate button. This will calibrate the LDT-R2 as well.
If using an LDT-E Series, on the LDT-R2 choose: Menu > Calibrate LDT-E
Once calibration finishes, from the LDT-R2 menu:
Choose: Menu > Add Lens.
Select an existing brand from the list, or input a new one if it isn’t listed.
To add a new brand, navigate through the available characters using the joystick's up/down movement. A single click advances one character at a time, while holding the joystick triggers rapid scrolling. Pressing right inputs the next character in the sequence.
Once complete, return to the brand list and choose one to continue.
Select Prime or Zoom according to the mounted lens on the camera.
Select an existing lens or add a new lens name if it isn’t listed.
To add a new lens name, use the joystick up/down to scroll through the available characters. One click for a single increment, hold for rapid scroll. Click right to type the next character.
Once complete, press the back button to go back to the brand list and select one to proceed.
Add a new focal length or focal range depending on the mounted lens on the camera.
Type the new focal length or focal range. Use the joystick up/down to scroll through the numbers. One-click for a single increment, and hold for rapid scroll.
If it is a zoom lens, click right to finish typing the focal range.
Once the focal length or focal range is entered, press the back button to go back to the focal range list and select one to proceed.
Enter a new lens serial number. use the joystick up/down to scroll through the available characters. One-click for a single increment, and hold for rapid scroll. Click right to type the next character.
Once the serial number is entered, press the back button to proceed.
¶ Creating a Lens Table
Mapping a new lens table is crucial to ensuring that the data encoded throughout the production is precise.
When mapping a lens, a methodical process needs to be adopted on both the remote lens control side and the LDT-R2 side. As standard practice, DCS suggests entering a mark point on the LDT-R2 for each engraved mark and letting the LDT-R2 interpolate the rest of the data.
Ensure that the lens calibration happens without any motor slip. When moving the lens axis with a remote handset, mark alignment should always be achieved from the same direction to avoid slack on the lens.
To retain the full precision of the focus knob, we recommend turning off F-Mapping during the creation of new lens tables.
¶ Initial Check
Ensure the Preston Hand Units and Single Channel Handsets are set for the natural Preston direction. DCS suggests keeping the motor setup consistent while the whole set of lenses.
Do not move Preston Motors or change direction while encoding the lenses unless required for rigging purposes.
As a general practice, when mapping a lens on the LDT-R2, always keep close focus on the left, wide open iris on the left and wide zoom on the left. An example below. If the physical movement of a lens axis is the reverse of the other lenses, then map it in the opposite direction on the LDT-R2 to avoid having to reverse motor directions each time this lens is recalled.
Make sure to never change the F-Map on the Preston HU3/HU4 while mapping a lens on the LDT-R2.
Please check the motor direction on the LDT-R2 is Normal before proceeding.
To check the motor direction
Choose: Menu > Settings > Motor/LDE setup
For more information regarding motor direction go to Changing the Motor Direction chapter
Mapping a Lens Table
Once all the lens information is entered, select either ‘SF’, ‘Focus’, ‘Iris’ or ‘‘Zoom’ (if a Zoom lens is being used) axis to begin mapping the lens.
¶ Selecting the Squeeze Factor
This option is only relevant if an LDT-F1 is being utilised for video processing. The default value is Spherical, which will not affect the map. If an anamorphic value is selected, the LDT-F1 will automatically apply the correct desqueeze value to the overlay whenever a new map is selected.
¶ Mapping The Focus Axis
Use the Preston focus knob to move through the span of the axis, the dot on the LDT-R2 display will move along the horizontal line. Ensure the dot reaches each end of the line. If not, check if there were any slips during calibration or disable F-Map on Preston HU.
Set the units of measurement for focus by pushing the joystick UP. Choose metres or feet.
Set the units of measurement for focus by pushing the joystick UP. Choose metres or feet.
Set the lens to the closest focus mark.
On the LDT-R2 press the joystick to enter the first mark, a pop up window will ask you to select the focus value.
Use the joystick to select the required value:
LEFT / RIGHTmoves between pre-populated numbers:0’ 1”, 3’ 0”, 10’ 0”, 30’ 0”, 100’ 0”, INFUP / DOWNfor fine adjustments.
Push the joystick to confirm the selection.
Proceed for each desired engraved focus mark.
Once completed, push the back button to return to the Edit Lens Table menu.
¶ Mapping the Iris Axis
Use the Preston HU slider or Preston Iris Handset to move through the span of the iris axis, the dot on the LDT-R2 display will move along the horizontal line. Ensure the dot reaches each end of the line. If not, check if there were any slips during calibration.
If a Single channel Iris Handset is being used, use it to make the maps.
Set the lens to wide open.
On the LDT-R2 press the joystick to enter the first mark.
A pop-up window will ask you to select the T-Stop value, use the joystick to select the required value:
LEFT / RIGHTmoves between stops:T0.7, T1, T1.4, T2, T2.8, T4, T5.6, T8, T11, T16, T22, 32, T45, T64, T90UP / DOWNfor fine adjustments,
Push the joystick to confirm the selection.
Proceed for each desired engraved iris mark.
Once completed, push the back button to return to the Edit Lens Table menu.
¶ Mapping the Zoom Axis
Use the Preston Microforce to move through the span of the axis, the dot on the LDT-R2 display will move along the horizontal line. Ensure the dot reaches each end of the line. If not, check if there were any slips during calibration.
A map can be created without the Microforce but the Zoom Direction must be checked before you make the map, so we would recommend using the Microforce.
Set the lens to wide zoom.
On the LDT-R2 press the joystick to enter the first mark.
A pop-up window will ask you to select the zoom value, use the joystick to select the required one:
LEFT / RIGHTto increase/decrease by 10mm,UP / DOWNfor fine adjustments.
Push the joystick to confirm the selection.
Proceed for each desired engraved zoom mark.
Once completed, push the back button to return to the Edit Lens Table menu.
¶ Testing the Lens Table
Prior to saving the lens map we suggest testing its accuracy. This can be done by pushing down the joystick when in one of the axes to enter the test window. Compare what is displayed here with the engraved marks on the lens to ensure the table is accurate.
Press the back button to go back.
¶ Pre-built Lens Table for Testing
The LDT contains a pre-built Lens Table intended for troubleshooting purposes.
- Choose:
Menu > Edit Lens > DCS Zoom test 11-110 (1)
This can only be selected with Auto Lens Select turned off.
¶ Saving a Lens Table
Once all the required values have been encoded, click on ‘SAVE’ to save the lens table.
A message will prompt upon successful completion.
¶ Edit a Lens Table
A lens table can be edited. New points can be added, existing points can be removed or a lens table can be permanently flipped.
- Choose:
Menu > Edit Lens
¶ Deleting a Point
If a point gets added by mistake or needs repositioning it can be removed.
In order to delete an existing point push the joystick to the left. Move the controller to the desired point. Push the joystick to remove the point.
Press the back button to go back.
¶ Flipping a Lens Table
If an axis map needs to be permanently reversed push the joystick to the right, then push the joystick to confirm.
If a map needs to be temporarily reversed we suggest reversing the direction of the motor.
- Choose:
Menu > Motor direction
¶ Using an LDT-E Series Lens Data Encoder
Camera operators may wish to manually control the zoom (or other axis) instead of using a motor that feeds data to the MDR. A lens encoder can be used with a motor, or in replacement of, allowing the LDT-R2 to still gather the lens movement data.
DCS has its own brand lens data encoder called LDT-E Series. These are plug-and-play devices so there is no need to create a new or separate lens table when using them.
Note: the direction of the motor might need to be reversed: please go to the Changing the Motor Direction chapter.
A video tutorial explaining the setup of the LDT-E1 can be found here
¶ Setting the axis for the Encoder
The LDT-E Series have a manual switch to set the axis to Focus, Iris or Zoom.
¶ How to calibrate the Lens Data Encoder
If using an LDT-R2/LDT-V Series without a Preston system:
- On the LDT-R2/LDT-V Series choose:
Menu > Calibrate LDT-E
If using an LDT-A2/LDT-M2 with a Preston system:
- On the LDT-A2/LDT-M2 press the blue button for 3 seconds
If using an LDT-R2/LDT-V Series with a Preston system:
- On the MDR3/MDR4 press the calibrate button
Then manually rotate the axis which is attached to the Lens Data Encoder from one end, pause for a second and then rotate to the other end. The LDT-E Series should now show as calibrated in the on-screen display.
¶ Changing the Motors direction
If for rigging purposes a lens motor or lens encoder needs to be reversed:
- Choose:
Menu > Motor directionand selectReverseon one of the axes.
¶ Transferring Data between LDTs
Specific data can be shared between LDT-R2s and the LDT-V Series to save time and ensure consistency across multiple set-ups.
¶ Transferring Lens Tables
.XML lens tables can be shared between all LDTs with a Micro SD slot.
The LDT-R2 saves individual lens tables as .XML files to the MicroSD card. If multiple LDT-R2s are being used, these lens tables can be shared between devices.
-
Insert the MicroSD Card with the lens tables on into a computer,
-
Copy the .XML files from the "LENSES" folder onto the hardrive,
-
Insert a formatted MicroSD card (how to format a MicroSD card for the LDT-R2),
-
Copy the .XML files to the "LENSES" folder on the new MicroSD card.
Back up the "LENSES" folder when any new lenses are added to the MicroSD card to avoid data loss in case of corruption.
¶ Lens Table Files Naming Convention
Each .XML file is named after the lens brand, focal length and last 3 digits of the serial number. Examples:
AOZ24987.XML
Angenieux Optimo Zoom 24-290mm sn.11218987
CVZ25324.XML
Cooke Varotal Zoom 25-250mm sn.5640324
ZU135767.XML
Zeiss UltraPrime 135mm sn.8185767
AS047211.XML
ARRI Signature Prime 47mm sn.9899211
¶ Lens Database
If the user decides to not use F-Map, the lens database can be organised as a list or as folders.
- List: LDT-R2 display.
- Folder: LDT-R2 creates a folder structure based on lens brand, type and a single file for each lens in the root of the MicroSD card.
¶ Lens Conversion for ALEXA
A computer is required for this step, in order to back up and transfer maps to the ALEXA USB or SD Card.
The LDT-R2 must be running firmware 1.49 or later for this workflow.
Once the lens map is completed on the LDT-R2, the file can be converted for use on an Alexa camera to make it compatible with the LDT-A2 and LDT-M2 units.
On the LDT-R2, Choose: ‘Menu > Lens Conversion’
Any maps that have not yet been converted will undergo the conversion process. A new TAB folder will be generated on the MicroSD card for this purpose. It is advisable to back up these files along with the XML lens files for added security.
At this point, users have the option to rename tab files. Since the ALEXA camera organizes lens files alphabetically, renaming maps to align with these names can greatly enhance user convenience.
The newly made Tab files can now be imported into the Alexa camera.
On an ALEXA Mini, Mini LF and 35, the LDT’s tab files should be added to the Alexa’s USB LDA folder.
The LDT-A2/LDT-M2 unit and camera settings should be in use at this point. The LDT-R2 is no longer needed after mapping is completed.
Then on the camera, use the ECS menu to import the lens files and select when appropriate.
On the Alexa Mini, Mini LF and 35, the 'LBUS Motor Configuration' Menu should have each axis set to 'Left'.
On the Alexa Camera, choose: 'ECS > LBUS Motor Configuration'
Inside this menu, ensure Focus, Iris and Zoom are all set to left.
This adjustment ensures that the map displays data in the correct orientation, aligning seamlessly with Preston's natural direction in which it was mapped.
It is recommended that all imported lenses are tested before production.
Warning: Ensure the Menu format of the Alexa USB is correct as it can lead to errors with importing lens maps
After selecting a lens map from the camera, the Preston must be calibrated. Data may at first appear static until the motors are moved.
¶ Editing Lens name on the ALEXA Overlay
To rename how the LDT displays the current lens on the ALEXA camera overlay, you need to modify the contents of the XML file before converting it.
For instance, if the F-map automatically fills in the name as 'Panavision Other,' you can change this to a specific lens type.
To do this:
-
Locate the relevant XML file in the LENSES folder on the MicroSD card.
-
Open the XML file using a text editor.
-
Modify the NAME field on the fifth line to reflect the desired lens name.
-
Save the modified XML file.
-
Reinsert the MicroSD card into the LDT
-
Use the "Convert Lens File" option in the LDT.
-
Import the new TAB file onto the ALEXA camera.
Ensure that the specific TAB file is not already present on the MicroSD card, as this will prevent the new file from exporting correctly.
When you load the new TAB onto the ALEXA, it will display the updated lens name.
An example of the XML structure can be found here:
- Brand name can be modified on the 3rd line.
- Type name can be modified on the 4th line.
Only alter the relevant text between the brackets.
In this example, the user would alter the word 'Panavision' for the brand change, and 'Other' for the type change.
<?xml version="1.0" encoding="UTF-8"?>
<lensMap version='1.1'>
<lensDetails>
<brand>Panavision</brand>
<name>Other</name>
<focalLength>10</focalLength>
<serial>100</serial>
<squeeze>100</squeeze>
</lensDetails>
<lensData>
</lensData>
</lensMap>