Sigma calibration when using a Sigma USB dock
Cautionary measures for those using the Sigma dock to preform a Sigma calibration......
As we have mentioned, Sigma along with Tamron allow users to calibrate and compensate for multiple focal lengths by way of an add on dock accessory. For Tamron it's the TAP-in Console and for Sigma its the USB Dock.
This method allows users to circumnavigate the restrictions imposed by camera manufactures such as Canon and Nikon. Specific Canon models allow for front / back correction values to be added for both ends of zoom as in 150mm and 600mm (with the case of the Sigma 150mm – 600mm F5 – 6.3 C or S models) whereas Nikon only allow for one end or the other.
However, both Sigma and Tamron allow multiple calculated correction values to be added to a lens by way of a “dock” which connects to the back of the lens. This dock is then tethered to a computer and synced to a corresponding app using an internet connection to access any relevant lens firmware updates. We'll expand on the use of the Sigma / Tamron docks in a further, more detailed post but until then though we thought we would highlight a problem experienced by one of our customers recently.
A Problem With The Sigma Dock
Said customer recently purchased via E-bay a Sigma 150-600mm F5.3 – 6.3 OS Sport and sent this in for calibration along with their Canon Eos 7D Mk2. Once out of the peli case, we set up the camera and lens combo on the test rig ready for calibration, following our normal workflow, we set the combo to the correct distance at 150mm and pre-focused on the illuminated test target and attempted to pre-focus. This action would normally result in correct focus being acquired and the calibration to start although in this instance NOTHING.
We checked all the appropriate focus settings followed by focusing manually to infinity and attempting to refocus, again nothing. The lens
was switched to another 7D Mk 2 only for the same problem to be found. We have seen this problem many times before and connected the Sigma dock to confirm our suspicions. Once connection was established to the Sigma app we were able to confirm settings had been applied to the dock interface (front / back focus correction values had been applied to various focal lengths). Settings had indeed been applied by the previous owner before it was sold on E-bay, but why was the lens not focusing?
With Sigma and Tamron great care must be taken when communicating / applying changes to the lens via the dock. As mentioned, a connection is made from the dock software to Sigma / Tamron’s servers via the Internet to check for any firmware updates, corresponding updates are then downloaded and applied to the lens. Any interruption in this sequence as in a drop in internet connection or disconnection can result in damage to the lens. This applies to any settings / changes applied to the lens, any loss in communication can have the same effect, the result as in this case, a dead lens.
So in this case, the previous owner attempted to apply corrections / update the firmware only to “kill” the lens because of loss of connection..
Did they check the lens after the incident? And if so did they decide to pass on the lens to what is sometimes described as the “camera / lens grave yard” which is sometimes referred to as E-Bay.
Not Covered By Warranty
In this instance, all ended well, better in fact as we were able to send the lens to Sigma for repair and after being supplied with an estimate for replacement of a new circuit board a dispute was raised with Paypal for recovery of the repair costs.
Sigma then decided to cover this under warranty.....
Please note this is an exception to the rule as interruption of an update is not covered by any warranty supplied by Sigma / Tamron. Any adjustments via the dock / tap-in console are undertaken at the owners risk.