Like the Sony GPS Location Recorder, the GPS Picture Tracker by ATP is a gadget that clips onto the camera strap or on the belt and records the position as you take pictures. When activated, it records a nonstop log of time and position to its internal memory, which can be compared to the time information encoded with the JPEG EXIF data by the camera’s internal clock every time a picture is taken. It automatically adds the location co-ordinates to the picture file. Therefore, the result can be shown on Google Earth, so that each photo is shown in its exact position.
Here are the EXIF datas of a test :
Camera: Leica D-LUX 3 Exposure: 0.033 sec (1/30) Aperture: f/2.8 Focal Length: 6.3 mm ISO Speed: 100 Exposure Bias: 0/100 EV Flash: Flash fired Orientation: Horizontal (normal) X-Resolution: 72 dpi Y-Resolution: 72 dpi Software: Ver.1.0 Date and Time: 2008:02:01 10:14:48 YCbCr Positioning: Co-Sited Exposure Program: Normal Date and Time (Original): 2008:02:01 10:14:48 Date and Time (Digitized): 01 10:14:48 2008:02: Compressed Bits per Pixel: 4 bits Maximum Lens Aperture: 30/10 Metering Mode: Pattern Light Source: Flash Color Space: sRGB Sensing Method: One-chip colour area sensor Custom Rendered: 1 Digital Zoom Ratio: 0/10 Focal Length In 35mm Film: 28 Contrast: Hard Saturation: High saturation Sharpness: Hard <strong>Latitude: S 33° 51' 48.4" Longitude: E 151° 12' 47.3" GPS Time (atomic clock): 10/1, 13/1, 17/1 GPS Receiver Status: A Geodetic Survey Datum Used:WGS-84 GPS Date: 2008:02:01</strong> Compression: JPEG Image Width: 4224 pixels Image Height: 2376 pixels
The only thing missing for KAP is the altitude ! The only “problem” is that the camera clock needs to be set to UTC/GMT, just like the GPS signals.
If you don't mind adding about 8 grams to the rig check out the Zlog recording altimiter. You can wire the shutter servo or GenLED through it and it will record the altitude of each shot. The file can be downloaded via USB but I'm not sure how you would get it into the EXIF data.
And here is another cool gadget that does something similar. It’s been mentioned on the forums before. Unfortunately, I don’t own one to tell you how good it is:
I've been using the RoboGeo ( www.robogeo.com ) application for my terrestrial photographs and archaeological site recordings. I just walk around with the GPS in my pocket with the track logging turned on and my camera and voice recorder synced to the same time as the GPS. Later, I drop the data into RoboGeo and it exports out a log off my days work. Really great using the voice recording feature when it’s too cold to write good notes. I’ve been doing my KAP work using the same method. Basically, just running the GPS from the ground, in my pocket, to have a general idea of where I was flying the kite when the photographs were taken. Ultimately, I want get detailed telemetry from the kite. In addition to coordinates and altitude it would be great to know the position of the camera in three dimensions. That’s probably a long way off.
Another useful application I see for positional information is for stitching : One would be able to sort frames according to distance between them, hence optimizing stitch result.
ATP is scheduled to be releasing a firmware upgrade soon to not only allow the PhotoFinder to record altitude but also to work with RAW files (though I would expect CHDK RAW will throw it for a loop, but that can be processed later as the RAW has the same file name as the JPG).
Now one thing to note is that even with altitude enabled on the PhotoFinder, altitude tends to be the weakest of the four data collection points (X,Y,Time,Altitude) so the gentvu-AltiOSD could actually be a useful tie into this at it would more accurately reflect the altitude.
One early review of the device noted some issues with PhotoFinder powering down to soon, but from the pictures that is not even the shipping model.
If you search on Amazon, for instance, there are an interesting number of GPS loggers out there in the same form function as the PhotoFinder, but the in unit embedding of the data in the exif of the jpg is not common.
Now Horus/Mark I am going to defer to you on this one: Can we (i.e. humans who lack your borg like connection to systems :-) correct the GPS data to a useful resolution? I can not tell if the data produced by this (or any of the similar USB GPS Loggers) produce data that can be converted into Rinex format which could then be post processed with the CORS (in the US) and the European EUREF data? I recall that these folks ( http://www.helenav.nl/rinex.htm ) offer some low cost converters (requires DOS 5.0!) that cover some of the chipsets used in these USB GPS data recorders (and the link to grn2rnx for the garmins) but I can not tell from the specs thought if the these USB GPS recorders bother recording enough information that could be converted. I would lean towards them not actually saving, in any format, the the pseudorandom code or ephemeris data which would be needed for precise correction.
It is to bad, from what I can tell, that none(?) of these technologies can easily display "tilt" of the sensor (as a unrelated side note, does anyone remember the "tilto-meter" globe on the dash of I think it was a line of off-road vehicles made by Mitsubishi? I used to drive this Japanese archaeologists Mitsubishi around lowlands of Guatemala and had a blast with that!).
Man, I had one of those Mitsubishis! It was re-labeled as a Dodge Raider, but it had the artificial horizon in the dash. Only vehicle I've ever had that had one, and I miss it still. (I now drive a Jeep, which can take much nastier inclines, so it's less relevant.)
Tilt is a bear ot get electronically. Even the one in the Raider was acceleration-based. If you swerved side-to-side, the horizon wobbled. You can do this with a 3-axis accelerometer, but wobbling of the rig will make the "down" reading wobble as well. Still, it's doable. Take a look at http://www.sparkfun.com - they have the three-axis accelerometers you'd need, and it should be possible to tie this into a real-time clock via a micro of some sort. Sparkfun also sells SD card interfaces that would let you go back into the EXIF data and put in your roll, pitch, and yaw data. But again, it'd be iffy at best. A 6-DOF sensor would give you pretty much everything you need, but they're not cheap. (Sparkfun has those, too.)
All in all, I'm just stoked the ATP units are getting altitude added as part of the package!! Even if the resolution is iffy at best, it's still better than nothing. I'm looking at upgrading my camera soon, and if things work out right I should have enough to pick up one of the ATP units. This pretty much convinces me that's the right thing to do. Altitude was the one missing piece I was really after.
Tom
P.S. I really do miss the dash instruments on my Raider. That artificial horizon was cool.
Joe, I’ve looked into doing differential correction with Garmin units a few times but the software doesn’t appear to be available any more. Unfortunately, knowing the location of the kap rig when a photograph is taken is only part of the equation. When it comes to stitching photographs together (in photogrammetry software anyway), the other important factors are the yaw, pitch, and roll of the camera. There are systems that track this information in high end UAVs. Maybe these can be purchased separately and modified to work on a KAP rig?
If you’re working in the continental U.S., the WAAS corrected GPS locations are normally accurate to within 20 feet and calculated on the fly inside the GPS. Also, you’re right about the Z values on traditional GPS being poor but traditional barometer based altimeters are available in many GPSes and more accurate.
Resurrecting an old thread, here (and I think this is my first post to the forum, as well); I've been carrying a couple of GPS receivers around with me for geotagging purposes for the better part of a year, now. I've written a couple of "ingestion" scripts which automatically download the track logs when the device is connected to my iMac or MacBook, indexes them by date in a small sqlite3 database, and then use those indexes when I import images from my cameras into Aperture to embed the location into the EXIF data. After the fact, I have an AppleScript/Python script pair which translates those locations to country/state/city. It's pretty darn handy and takes a lot of the pain out of geotagging images (provided you remember to always ingest the location data before importing the photos).
I started out with an AMOD AGL3080 screen-less datalogger, but that died on me on the first day of a week-long trip to Canada and I ended up buying a Garmin 60cx at a Canadian Tire for a princely sum. The beauty of both of those devices is that they log to files and are Mac compatible. My import process writes the files out to GPX format, and my geotagger just works with those files, so it's fairly extensible. One downside is that I do have to keep keep my cameras set to UTC, just so I don't have to worry about time zones and DST; the scripts could be modified to take time zones and DST into account, but would require more human intervention.
The upshot of all of this is that after a day of shooting or walking around town, I plug in my GPS and wait for the notification to appear on my computer that the import is done, and then I import the pictures into Aperture. No muss no fuss. I'm happy to share all of this with anyone who's interested.
I'm still working on this issue in an off-hand way. A friend is developing an IMU/GPS NAV board for a UAV, and we've been trading notes a lot. Pretty sure I can get a fairly decent roll, pitch, yaw from off the shelf hardware. But I'm waiting to see the error bars on my friend's NAV board before I start buying hardware. From what I can tell, though, it wouldn't be a big weight penalty for a KAP rig. But the devil is in the details. It's the filtering from the sensors that makes or breaks a system like that.
I too just have a gps unit in my pocket (a garmin device) and use a freeware tool called Geosetter to sync the gps data to the EXIF info on the photos when I get them on my PC. I'd love to have something that reported back alitutude tho, so I can figure exactly how high I've flown my kite at last !
Yeah, Scott, that could work, as could a web service I've seen which will report back the time zone for a given lat/lon, but that just isn't absolute enough for my OCD-addled brain. The downside to Aperture is that the EXIF data is read-only, so there's no going back to correct it after the fact. The only way the automated geotagging process will work for me is if it's completely hands-off. By setting my camera to UTC, I never have to worry about changing the clock for daylight savings time or timezone when I travel (which is seldom). Of course, I have to do a bit of math whenever I want to figure out what local time is by looking at the camera, but even I can usually handle subtracting four or five! :-) Post-import, I use Aperture to change the timezone on the image and all is right with the world.
Does anyone know if the following exists - a small GPS unit with a screen that provides a readout of position on request and nothing else. So I could press a button to wake it up (saving power) and just read out my position when I am photographing. Then I could make a note of each KAP, pole or normal photo location and it would also be handy for walking and cycling. I don't need altitude (I have an altimeter if I need it) or any other functions on the equipment.
What's your use-case, Tony? Are you just curious what your current lat/lon is? Do you intend to take a picture of the screen? The Garmin eTrex H is only about $89 (USD) from Amazon and is about as bare-bones as you could ask for. It doesn't do maps, and doesn't even come with a data cable (for transferring waypoints), but it fits your criteria for a box with a screen. It's rated for 17 hours on two AA batteries.
What's funny is the original eTrex 10 years ago was $89 dollars and had pretty much the same functionality. I have a bottom of the line Magellan from way back and my only complaint is that it needs another significant digit. Back then it didn't matter, but since things are unfuzzed it now does.
Anyway, ebay or pawn shops might be the way to go. Basic GPS units haven't changed in years.
Hi Kev and Brian - thanks for mentioning the Garmin eTrex H. Garmin products were the first I looked at and I found this product quickly enough, but Garmin's information and websites are are useless (to me at least). They call it a GPS receiver which is what I want, but the screen shots suggest that it is a compass (which they say it is not) and show other irrelevant information. On the dozens of sites I have looked at I can see no indication that it can show latitude and longitude info.
Brian - I want to be able to record the position (my position) when I take photos, nothing more than that. I could photograph the screen or just write it in a notebook. I don't want to bother with putting this data on the EXIF or synchronising times etc. I will put the info into a cataloging program manually when I get home for the images I want to keep and perhaps for one in a thousand images I might put it on the EXIF myself. The reason is simply to be able to identify where groups of images were taken after 10 years or so. I never take JPEGs, so many of these purpose made units are useless. A secondary use would be to be able to identify my position when walking or cycling, when I would be carrying a map and a compas anyhow.
tgran - that's an interesting idea. Thanks, I will see what I can find. I don't think I even need the significant digit for my KAP activities!
Any handheld will display coordinates. Rather than copying them down it is easier to enter the frame no as either a wpt i.d. or comment, then download the whole lot as a data file.
Here's a link to the eTrex H owner's manual. There is a trip computer page with customizable data fields. I'm about 99% certain that one of those fields will be the latitude and longitude. Really, I can't imagine *any* GPS receiver not being able to show you your current position! tgran's suggestion of looking for used ones is a good idea.
For what it's worth, my workflow above is for RAW as well as JPEG. I shoot RAW+JPEG with my Panasonic LX3 because Aperture doesn't support the RAW files (*grumble*), but I shoot *only* raw with my Canon 40D. It just so happens that the utility I use to stuff the position into the EXIF data supports a pretty wide range of RAW formats (and JPEG, obviously).
The "compass" function actually just gives you a vector by looking at your last few positions. If you stand still it will lose it's sense of direction but it does pretty well at a good walking clip. Most of the cheap GPS units have at least 3 or 4 screens -- including satellite display, Lat/Long display, current direction + speed, crude map of user waypoints + cities, etc. My guess is the main improvement over the last 10 years is battery usage.
For those getting into Arduino / microcontroller stuff there are pretty cheap breakout boards that could be integrated into rigs.
I asked Garmin and received the folowing response, so it looks as if any of their hand held systems will do what I want. "Thanks for your email I will be happy to help. The Etrex H would be fine for what you are wanting to use it for. the unit has a mark feature on it that will mark a waypoint at your current position. What you will be able to do is once you have a position select mark and this will mark and save the waypoint at this position. All our units will allow you to view position in LAT and LONG.
You can also set up one of the data fields on the devices trip computer page to display your position. It may also be worth considering the GPS 60 as this will be easier for you to interface with the PC as it has a USB output and it also come's with the trip and waypoint manager software in the box which will allow you to transfer your saved waypoints routes and track to your computer."
There's a new gadget for geotagging coming out soon called the Phototrackr Mini. It's about the size of a flash drive and costs $69. It compares time stamps of your lat/long/altitude with your camera's time stamps to add geotagged EXIF to your pictures.
I think I had an early version of Picture Trackr by ATP - bought it about 1.5 years ago. It was briefly sold at Costco. There were big design problems with the early model - mostly because you had to be able to read the tiny, crappy LCD to setup, and I could not read it. Acquisition time was horrible, too. I figured that the next models would be sure to solve those problems. The beauty of it is how it was used ... make sure camera is set to same time as GPS (UTC is simplest) and at end of day, put your SD card into the unit and it would automatically geotag all photos. Are their others that can do the job without requiring computer?
