Sulhan Photography

Building a wireless USB Link for wireless tethered shoot on Sony Alpha A900
- by M Sulhan Juman

We have been looking out for a wireless data transfer solution for the Sony Alpha to enable it for use in a wireless tethered shooting situation.  This setup was to compliment or maybe replace the wired setup that has been used in the Mobile Photo Studio print station solution over at Mobistudios.  We have just secured a major event this October that will be a a good platform to try out a new solution – such as a wireless tethered shooting solution for use in the mobile print station setup.  After drafting out the plans for the two day event, we’ve decided to go ahead and build a wireless solution for our usage.

We searched the web for wireless tethered solution for the Sony Alpha DSLR cameras and did not find any solution documented for Alpha cameras in any of the technologies – such as USB, Wifi or others.  Fortunately we found a write-up by a fellow photographer by the name of Pete Tsai – who have successfully build a USB link using hardware by Cables Unlimited for his Nikon system.

Also highlighted on his blog is the new version of the products by Cables-to-Go which apparently is the new range of product replacing the earlier black version that he used in his DIY.  We then went on a shopping spree here in Melbourne looking for the USB link device from Cables-to-Go.  Unfortunately, we can’t find any outlets or local shops here in Melbourne carrying this part.

We manage to get help from a contact in USA to purchase one form Amazon and have it delivered to us.  Within a week, we got a visitor form the local postal service handing us this large package.

1.  The Cables-to-go Truelink Wireless USB Device Adapter Kit

Here is a shot of the items that came inside the large box.

Fig. 1 The Items in the package

The package consist of the following items:
- 01 x USB transmitter unit
- 01 x USB receiver unit
- 5V power adapter
- 01 x USB cable for initial “Association” process
- 01 x Extension dock for the USB Receiver
- 01 x User Manual
- 01 x Quick start Guide
- 01 x Driver in CDROM

The main item of attention here is actually the USB wireless transmitter and receiver unit as shown here.  As compared to the USB adapter product by CablesUnlimited, this product from Trulink comes with removable antenna solution for both the transmitter and receiver.  The removable antenna is similar to the type used on wi-fi devices which could be configured to be at a right angle position.

Fig. 2  The Transmitter(Right) and Receiver(left)

We immediately got all that was necessary to get this hardware tested.  Based on Pete Tsai’s website, we basically need the following:

- A +5V DC supply for the transmitter and
- A hosting PC that runs the Tethering Application

2.  Our First try of the wireless setup on the Sony A900

We rigged up a battery storage holder to be a battery pack to churn-out a +5V DC supply for the transmitter.  This is a short material list of the power pack:

- 04 x AA sized Duracell 1.2V NimH battery – to give us a 4.8V supply (this was a dirty setup that does not have any regulation etc.).
- 01 x Usable Battery storage pack with retrofitted foil contacts to create the circuit
- DC plug head to match the USB transmitter’s power socket.

Here is a quick sketch of the setup and its connectivity:

Fig. 3 Setup Connectivity Diagram

a) The setup process based on the steps we took:

1- Install the Trulink wireless USB driver on to the PC where the Remote Camera Control was installed.
2- Insert the Trulink wireless USB Receiver dongle on to the USB port.
3- Setup the camera to be in Remote PC mode.
4- Plug in the USB connector to the data I/O port on camera.
5- Connect USB connector to Trulink wireless USB Transmitter.
6- Prepare the +5V battery pack for the transmitter power supply.  We used 04 x AA Nimh 1.2V batteries which totaled up to +4.8V which worked fine with the transmitter.
7- Connect up the power supply to the transmitter unit.

Once that was done, the next step is to get the connection up and running.  We followed closely the first steps for the “Association” process for the USB device as laid down in the user guide.  Once the “Associaiton process is done, we proceed with these steps below:

Fig. 4 All connected and ready to go

Once “Association” is done, we were ready to go.  Here are the steps for connecting to the Remote PC application.

b) Establishing Remote Camera Software control

1- Make sure Camera is powered up and set to REMOTE PC mode for the USB connection.
2- Ensure all wires connected and Transmitter is powered ON.
3- Ensure that Receiver unit  is connected and the receiver “blue” light showing an established link is ON.
4- If the association process is done correctly – At this stage the PC will show a USB Device Hub connected and the following window will appear:

Fig. 5 The default Windows program launcher pop-up

5- Ignore the window above and launch the Remote Camera Control software (Sony Software)

6- A pop-up window showing the “Inactive Remote Control Interface (shown below – Fig. 6)” and  available USB device connected (Fig. 7) to be used and will come up:

Fig. 6 Inactive Interface Window of the Remote Camera Controller

Fig. 7 Device Section pop-up

7-  Proceed to select the A900 on the pop-up selection window (Fig. 7 above) and you will immediately see the “establishing connection” pop-up window for a few seconds while the software establish connectivity with the camera.

Fig. 8 Windows status pop-up during establishing connection

Fig. 9 Message on LCD screen during the establishing connection process

8- If connection is established an the Remote Camera Control software takes control, the LCD display on the Camera will show -PC- on the bott0m right hand corner.

Fig. 10  The Camera in the – Remote PC connecion mode

9- The Remote Camera Control software will have its interface up and all controls on screen enabled (Fig. 11 below)- indicating that the camera can be controlled remotely.

Fig. 11 All controls active with current camera settings

On the Remote Camera Control software interface, you can have a choice of having images downloaded and opened up in the Image Lightbox SR software (by selecting the check box) and alternatively define a download directory of your choice.

3. Data transfer rate with different file sizes

On our setup, the initialization and functionality of the hardware worked really well .  A full 24 Mpix-Fine image took about 10 seconds to transfer.  24Mpix for the mobile print station is a little too big and we tried transferring the intended data size of 6Mpix (small+ Fine +Jpeg).  When used in the 6Mpix+Fine +Jpeg mode, the data transfer is instantaneous.

We tried multiple burst shot in the small 6Mpix+Fine +Jpeg mode till the buffer is full and the images are sequentially downloaded without any problem.
There is no problem in maintaining communication between the camera and the host PC during out normal tests – even with larger 24Mpix files.  Larger files basically means slower transfer and this does not cause any data transfer problems like disconnection etc.

4.  Working distance

Our goal is to achieve a wireless channel of up to 3 metres.  From our random tests, we manage to have full connectivity without any data drop out up to a distance of 8 metres indoors.  This gave us a safety margin beyond our needs.
The wireless channel is greatly affected by any large obstruction hence operating the device in the widest possible unobstructed channel is therefore recommended.

5.  Building the housing for the setup

The next step was to build a proper housing that could be used to hold the setup.  Here is a short slide show of the prototypes that we crated.  After a couple of iterations, we finally found the right design to move forward to complete this project.

The layout and planning of the setup was done in Google Sketch-Up.  For those who would like to improve the design and work on improving ther design themselves, you can download the Sketch-up drawing file here.
- Sketchup file for USB wireless link prototype

6.  Wrapping up this DIY project

This Wireless USB link worked well and met our expectations.  This solution extends what a photographer can achieve with their existing tool and improve productivity.  We really wold hope to see a cost effective dedicated solution developed for users of the Sony Alpha DSLR/SLT systems in the near future.

To those out there who would do have any queries or questions with regards to this Wireless USB project, please do feel free to drop us a note or comments.  Happy trying, happy shooting and have a nice day!!!

11 Responses to “Building USB wireless Link for A900”