Ever since I learned about the ability to imbed GPS location into the EXIF information in my digital photos, I’ve greatly desired to do so. The Nikon D200 (along with a few other Nikon cameras: D2X, D2HS, others?) requires little effort to do so, just an expensive and difficult to find MC-35 GPS adapter cable and a battery powered powered GPS with a DB9 serial port that speaks NMEA at 4800baud. This solution can be about $300, depending on the cost of the GPS (MC-35 is $100).

A homemade solution can be had for about $175 and turns out is quite easy to do, provided you can acquire the MC-35. Read on for details.

NOTE! My next GPS project for the Nikon D200 (just completed) does not rely on the MC-35 and can be built for less than $100 and is much smaller and more manageable. I will be posting information about it soon.

Overview

The idea is to replace the most expensive item (the GPS) with a comparable product and to alleviate the bulkiness of the GPS by removing its power supply and replacing it with power from the camera.

The GPS is replaced by a OEM Garmin GPS (GPS18 LVC - no software, no connector, lower cost) and is powered by the 5vdc supply, available from the 10 pin connector on the front of the camera (can be tied into the MC-35 with a simple modification).

Warning

This procedure involves soldering very small areas on a circuit board. Performing these steps will certainly void the warranty on your expensive MC-35 GPS Adapter Cord that you waited so patiently to receive. There is also the possibility that your even more expensive camera could be irreparably harmed due to faulty soldering. I cannot be held responsible for any damage done as a result of this procedure. Consider this fair warning and only proceed at your own risk if you agree to these terms.

Part List

• $99.95 Nikon MC-35 GPS Adapter Cable Available (sometimes) at B&H Photo
• $65.79 Garmin GPS 18 LVC (OEM Series) NOT USB
• $1.79 9-Position Female Solder D-Sub Connector Radio Shack part #276-1538
• $1.79 9- and 15-Position D-Sub Connector Hood Radio Shack part #276-1539
• $5 (or less)  Broken or very cheap flash unit (hot shoe needed)

Procedure

1. First, acquire the MC-35. It took at least four months to get mine.
2. Supply power to pin 9 (Ring Indicator) of the DB9 connector on the MC-35.
1. Remove four small screws from top of MC-35.
2. Open the plastic box carefully; note the bottom of it comes off leaving the cable and circuit board with the connector.
3. Very carefully, solder a wire from Vcc to pin 9. The Vcc terminal is clearly labeled on the circuit board. You could also choose Vbat which would have a continuous power draw on the camera’s battery. Vcc is only active while the camera is active. Note that if the camera is receiving GPS data, the camera remains active. Pin 9 on the DB9 connector is the rightmost pin on the row of four pins looking at it si that the 4-pin row is on the top.
4. (optional) If you have a voltmeter you may want to make certain that your soldering is correct.
5. Close the MC-35. Note the rectangular rubber connector is placed vertically in the hole on the other part of the connector before closing it.
3. Attach the female 9-pin D-Sub connector to the GPS cable, trimming the cable to the desired length.
1. Determine the length of cable attached to the GPS you will need. I would suggest allowing extra cable because it is much easier to shorten the cable length than to enlarge it.
2. Strip two inches of the black casing from the end of the GPS cable. This should reveal six wires: two black, one red, one green, one white and one yellow. The yellow cable is not used and can be safely cut back for this application.
3. Solder the black wires (Ground) to pin 5 of the DB9 connector. Pin 5 is labeled on the back of the connector; it is the rightmost pin on the top row (with 5 pins) looking from the back of the connector.
4. In the same fashion, solder the red wire (Vin - 5V) to pin 9 (bottom rightmost pin). This is going to match the 5V on pin 9 supplied by the D200 by pin 3 of the 10-pin connector (through the modified MC-35).
5. Solder the green wire (receive data) to pin 3.
6. Solder the white wire (transmit data) to pin 2.
7. Attach the connector hood to the DB9 connector.
4. (optional) Remove the hot shoe from the base of an old (or broken) flash. Determine a method to connect the GPS hockey puck to the shoe. This will prevent fiddling with the puck while trying to take pictures. Note the bottom of the GPS has a magnetic base. Do not let it come in contact with your Compact Flash as it may destroy any information on the card. I would also be weary of getting it too close to the camera as the magnetic surface may harm the camera. I chose to leave a long length of cable attached to the GPS and then keep the GPS in a pocket or on the ground while shooting.
5. Plug the MC-35 into the DB9 connector of the GPS and attach the 10-pin connector to the D200. If everything has been done correctly, a flashing GPS will appear on the LCD display on the top of the GPS. Then the GPS sign stops flashing and remains, a location fix has been achieved and GPS information is available to the camera. Pictures taken now will embed the GPS coordinates into the EXIF information of the digital image.

Unfortunately, the Garmin GPS 18 take a while to lock on to a signal and is not as sensitive as other GPS devices. Also, I can only have the camera on for about two hours before the GPS drains all of the life out of the battery. When not in use, it is wise to either turn off the camera or disconnect the GPS from the MC-35.

My next project aims at reducing the expense and complexity of this project. Keep reading for details.

 

This entry was posted on Thursday, December 21st, 2006 at 11:55 am and is filed under GPS, WILT. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.