The left hand kanji loosely translates as "Medium" and that the right hand one translates as "Feeling".

A Valuable Tool when Buying, Selling, and Servicing Lenses

With the Camera FAX , you can:

• Offer a standalone service, creating an extra income stream. Quick and easy to use, it works seamlessly In-house and at workshops. 
• Create a Test Report — a powerful sales tool that showcases your work and builds customer trust.

The Lens Professional Camera FAX includes:

• Custom Headers and Footers: Add your contact information, logo, and terms of service.
• General Information: Model and Firmware version.
• Internal Serial Numbers: Lens ID and Lens Body ID.
• Drive Counts:  Diaphragm, AF and IS Units release counts.
• Error Codes: Error recording of Diaphragm, AF and IS Units.
• AF Compensation: Compensation numbers of all AF systems.
• Image Stabilisation:  IS Unit; Shift, Gyro, Central and Gain
• Test Report: A report of all the tests conducted at this workshop on this lens.

Inspecting Focus Compensation helps Troubleshoot AF Problems

⚠️ Viewing Focus Commpensation is NOT a test of Focus Compensation accuracy!

This menu helps you check if the Focus Compensation in the lens is working properly without Disassembly. 

• Focus Compensation allows the camera to adjust focus more accurately based on the specific lens you're using.

As you slowly turn the focus and zoom rings, the display should show smooth changes in values. If the values don’t change, or if they jump suddenly, there might be a problem—like a damaged internal part (called a wiper) or a corrupted memory chip in the lens.

This tool is useful when you're having Auto Focus (AF) issues.

Problems Caused by Faulty Focus Compensation

• Front or Back Focus
• Inconsistent AF Accuracy
• Focus Shift While Zooming (Zoom Lenses)
• Erratic Autofocus Behavior
• Poor Low-Light Focus Performance
• AF Micro Adjustment Has No Effect
• Focus Errors After Main Board Replacement

Zoom Encoder problems can affect Flash, Image Stabilization and Auto Focus

This menu lets you test if the Zoom Encoder in your lens is working correctly without Disassembly. 

• Problems with the Zoom Encoder can cause issues with Flash, Image Stabilization, and Auto Focus.

It works by showing you a signal as you slowly move the zoom ring. If the display matches the lens zoom and all boxes light up smoothly, the encoder is working. If not, the encoder might be damaged—usually from bent or broken parts inside.

This signal also helps control the flash power when using ETTL flash.

Possible Problems from a Faulty Zoom Encoder Brush

• Inconsistent or incorrect ETTL flash exposure
• Poor or unreliable image stabilization (IS) performance
• Autofocus hesitation or inaccuracy, especially at longer focal lengths
• Incorrect or stuck focal length in EXIF data
• Possible lens communication errors or camera error messages
• Flickering or image shift during zoom in live view or video mode

Having an Auto Focus Problem … start by checking the Focus Encoder

This menu helps you check if the Focus Encoder in your lens is working properly, without disassembly. 

• If you're having Auto Focus problems, this is a good place to start.

It shows you a signal as you slowly turn the focus ring by hand. If the signal moves smoothly and all the boxes on the screen light up during the test, the encoder is working. If not, there may be a problem; often caused by bent or broken parts inside the lens.

Also, this same signal is important in setting the power level for ETTL flash.

⚠️  The most common cause of encoder failure is bent or broken wiper blades on the focus brush.

Troubleshoot Subassembly Errors / Reset the use Count if you replace a Subassembly

Clear the Error Codes after Repair

Newer L-Series Lenses Record: Actuation Counts and Errors

These lenses track usage and errors from key internal components:

• Diaphragm Unit
• AF (Autofocus) Unit
• IS (Image Stabilization) Unit

Error Window

• This window identifies errors in malfunctioning units, helping you pinpoint the source of the issue.
• Example:  IS Unit – Gyro Sensor: Anomalous

This data provides a clear picture of the lens’s overall condition and can help identify malfunctioning sub-assemblies.

Reset

• Use Reset to zero the actuation count after replacing a sub-assembly.

Clear

• Use Clear to erase error codes after performing repairs.

Change the Electronic Serial Number in the Lens

Lens ID Number

• This is an internal factory-assigned serial number. This normally will not match the serial number printed on the lens. There is no reason to change this number, it's used primarily for factory reference.

Lens Body Number

• This is the electronic serial number of the lens and should match the number printed on the lens body.

⚠️ Not all lenses include an electronic serial number. If your lens does not have one, the 'Lens Body Number' field will not appear in this Menu window.

Change

• Click ‘Change’ to update the electronic serial number so it matches the number printed on the lens body, if needed.

Save and Restore Lens Calibration Data

⚠️ Always Backup the Calibration Data from the Original Main Board before making any changes.

Backup … is used for replacing Main Boards or before making Adjustments.

Restore … is used when you replace a Main Board AND you were able to save the Calibration Data from the Original Main Board

Initialize …. is used when you replace a Main Board WITHOUT the original Calibration Data

If you were not able to download the Calibration Data from the original Main Board:

1. Install the new Main Board.
2. Use this software to Initialize it.
3. Then calibrate the lens using this software.

Question from Accurate Instrument Servicing Pty Ltd

“Would it be correct to say it’s basically not possible to get 100% AF focus—only very close—because of mechanical or possibly optical tolerances?”

Answer

Yes, that's essentially correct. Most lenses are not manufactured to tolerances that can always achieve perfect Auto Focus. However, a good lens will consistently front or back focus by a predictable amount.

To correct this, lenses include a data file called Focus Compensation, which tells the camera body how much to adjust to achieve optimal focus. This is not an autofocus (AF) adjustment on the camera—it is lens-specific data used by the camera’s AF system as part of its focusing calculation.

Lens Focus Compensation – Quick Overview:
Focus Compensation is designed to make a lens provide the best possible AF performance across all camera bodies (assuming the camera body AF system is properly calibrated).

• It is not an AF adjustment.
• It is used by the camera as part of its autofocus calculations.
• Calibration is for the central AF frame in the viewfinder.
• Different calibration values exist for:
  • Different AF sensor types within the central frame
  • Different zoom settings
  • Different EOS AF system designs

For Canon Lens Professional Software Users

More details can be found in the Software’s ‘Help File’
Help → Using the Software → Lens Operations Menu → Focus Compensation – Adjustment Overview

Purchase Details

1. Connect your Lens to your PC, through a compatible camera Body.
2. Connect your Lens to the Software.
3. Click 'Connect' -- if the Lens Plugin is not installed, you will get an alert
4. Purchase the Plugin and wait for your ‘Plugin Confirmation Email’ from SPT.(Your Invoice is NOT the Confirmation Email)
5. Relaunch your software and click:  ‘Connect’ / ‘OK / Install or Install All (for multiple Lens Plugins).

The Effects of Lens Release Dates and Firmware Versions!

Older Lens and Firmware versions have fewer Supported Operations - allot fewer!  SPT Canon Lens Professional software always uses ‘ALL’ Operations that the Lens and Firmware supports.

SPT’s Canon Lens Interactive Software

Outwardly two same model Canon lenses may look identical, but variations in manufacturing dates, firmware, etc. can make them very different lens to service.  

Canon Lens Professional and its Plugins automatically synchronize its Supported Operations, Adjustment Menus and Service Methods specifically to the Canon Lens being serviced!