Home  GPS-enabled photos
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Sony A55 DSLR Camera - Guest Review |
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by Joel Cusick, National Park Sevice, Alaska Regional Office
Right-click and choose Save as to download the Sony GPS-Camera Review
As an ardent fan of all things Geotagged, I wanted to share with you some
observations with one of the consumer digital cameras on the market today
with an integrated GPS and compass versus the features and accuracies of a
"mapping" grade photo system.
Ingredients
- Sony DSC-HX5V digital camera
- Garmin Map76CSx set to Tracklog
- Trimble GeoXT 2008 w/ TerraSync 4.1 and DDF with a file name attribute for associating photos
- Trimble TrimPix Professional
- Trimble Pathfinder Office
- Geospatial Experts GPS Photolink Version 5.0 for watermarking and analysis
Background
I recently purchased a Sony DSC-HX5v digital camera with embedded GPS and
compass. It has SDHC memory capacity so TrimPix can be used. This is new
for Sony to offer a non- propiertery Sony Memory stick as a storage option
(finally). As GPS/GIS professionals, we are being asked to evaluate and
recommend GPS-integrated cameras for use in GIS applications. I'm the
first to welcome these integrated technologies to expedite the geoposition
of photographs however, there are considerations when we think about
features (points) being mapped with attributes and the photo subject (the
thing you are mapping). For certain jobs (aircraft or scenery overviews or
preliminary trail layout), an integrated GPS/Camera may serve really well
as a first look. I've been using the Ricoh 500SE for years, and consider
that camera top-drawer for GPS integration and features not found in the
consumer line. It's just that many folks complain about cost, size, and
why bother when you can get a camera/GPS/compass all in one. I have some
comparisons that highlight issues that should be raised and considered with
such systems.
Overall thoughts on the camera
I really like the Sony. A price point of about $350 was right for me. The
compass is quite good (after calibration) and responsive. Magnetic only (no
declination). Battery life is good. I bought an extra spare, and shot 150
photos over 6 days with plenty of energy to spare. Will not accept AA. The
GPS is on top on left side of camera away from your finger over shutter
(good idea eh?). The GPS takes from 5 seconds to 3 minutes to "acquire".
GPS display is reduced to showing one to three bars (coords not shown). If
you had the camera on within 30 minutes, the acquisition is under 1 minute.
I always held camera up above head to maximize time to acquire (a photo
stance for the future), but even under moderate canopy, acquiring signal
takes time. Sometimes turning on/off camera helps. There is nothing to
show that you have a fresh GPS position except 3 signal bars. If you don't
wait to get a signal bar, the previous position will be used to tag photos.
All photos will be tagged in even if you show no signal. You can turn off
GPS (stop tagging), but getting to the menu to turn off GPS is about 10
clicks. There is an EASY button setting that makes the GPS from menu
accessible to turn off quickly though. There is no feature to "LOCK" GPS
onto the photo subject, then step back and take the photo from the
photographers position.
Accuracy
A few tests in various Alaskan country shows the Sony works pretty good in
the open Slide 4 (range of 2-5 meters), but under canopy error budgets
increase dramatically Slide 5 (witnessed 200 meters). The open sky
environment is adequate for these systems. That's a picture of Denali -
North America's tallest peak from Denali State Park. Wonderful shot!
No GPS position is better than a really wrong one
Since this camera tags all photos regardless if the GPS has a hot fix or
not, you can tag a photo miles from it's position. A habit of mine is to
turn on the camera, shoot the photo and turn off camera to conserve battery
life. Unless you give these camera's time to fix, you can embed extreme
inaccuracies, harming a mapping project more than it helps. I would much
rather not have any gps position than a really wrong position.
Inability to Offset from a Photographers Position
Again, no big deal if you in an aircraft shooting photos where you don't
mind having the position of the camera coordinates embedded, but a bigger
deal when on the ground and tying the photo to a feature. Tying the
photo of the subject (the feature) to the feature is important to reduce
map confusion and matching photo management.
Slides 6, 7 and 8 show a scenario where offsets come into play. The Sony
(Slide 6) cannot determine an offset, plus it has inherent accuracies that
place the photographers position in errors of 10 - 30 meters away from true
photographer position. While the Trimble (Slide 7) has the ability to
offset and "bind" one or more photos to a particular point feature. In
this case, I took 2 photos (1 and 2) of a building, and associated those
photos using TrimPix to a building primary entrance point feature. I took
another photo of a sign along the west side of a road and associated that
photo with a Sign point feature. In the first mapping scenario I want all
photos assigned to one coordinate - the primary entrance. Turn to Slide
8. Hence, i will stand off from the building, offset the GPS antenna
position to the front door and fire my photo. This way I conserve energy,
and maximize efficiency by mapping and shooting from the same spot. I then
Paused the Feature, walked around to back of building and took my Photo 2.
TrimPix sent both photos to my datalogger and i selected both photos and
closed feature. I then opened my Sign Point feature, offset the point to
the sign, fired my photo, wirelessly transmit my photo via TrimPix, and
close feature. In Slide 6, you can see the result of all photos.
Watermarking from GPS PhotoLink stamps the photos with the Postprocessed
Exported true position of the GPS. Coordinates are blocked to protect the
innocent (:><).
Having GPS PhotoLink to handle all the final photo processing is still valuable
for seeding true Differential positions from an export back into the photo,
watermarking and file management of the photo batch
Can You Have a GPS Camera and TrimPix?
Sure! Any camera with a GPS most likely is SDHC compliant. Hence, TrimPix and a GPS
embedded camera serves as a backup to a workflow. TerraSync overwrites
the in-camera GPS positions on photo association to the feature, but having the raw
gps photo can serve as a backup in case things go really wrong in the field.
******************************************************
Joel Cusick
National Park Service/Alaska Regional Office
240 West. 5th Avenue, Anchorage, AK - 99501
(907) 644-3549
This e-mail address is being protected from spambots. You need JavaScript enabled to view it.
+61°13.0213', -149°53.1763', (NAD83 CORS96)
6VUN4499490383 USNG
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Many thanks to Joel for his never-ending enthusiasm and support! |
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While we have not yet had a chance to play with these new toys, please check out the guest review of the Sony A55 DSLR Camera. Click on each title for each company's own press release.....
Sony A55 DSLR Camera and Lens
Model Features: 16.2MP, Translucent Mirror Technology™, Quick AF Full HD Movie, GPS tagging, Live View with Phase detection, 10 fps, 15-point auto focus, 18-55mm zoom lens included.
Read our guest review of this camera by Joel Cusick, National Park Service GIS/GPS expert
RICOH ANNOUNCES G700SE DIGITAL CAMERA WITH BLUETOOTH® AND WI-FI
Complete with wireless data communication capabilities (Wi-Fi) and Bluetooth®, the G700SE uses Global Positioning System (GPS) functions and laser barcode readers. The camera also features a Scandisk card (SD-1), which provides a higher level of security with password-enabled access. By sliding the card into the camera, a user can only read information by entering the correct password.
CASIO RELEASES COMPACT EXILIM® CAMERA WITH HYBRID GPS
The latest model to join Casio’s EXILIM Hi-Zoom lineup, the EX-H20G offers an impressive feature set as well as Casio’s state-of-the-art Hybrid GPS technology, which makes the camera perfect for traveling. Thanks to Casio’s Hybrid GPS system, the EX-H20G offers ultra-precise location data for the geotagging of photos and videos and is also the first camera able to geotag indoors. Additionally, the EX-H20G can display the user’s current location - as well as geotagged photos and videos - on a map which can be viewed right on the camera itself. |
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Hardware: Ricoh GPS Camera |
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This excerpt from the technical note in the Burning Man Monitoring Report demonstrates how over 1,2000 GPS-enabled photos used to monitor and document week-long Burning Man event. Four Ricoh 500SE cameras were used to photo-documentation everything ‘good, bad or ugly’ at the event. The Ricoh cameras, combined with Geospatial Experts GPS-Photo Link and ESRI ArcGIS software made it possible to complete the 10 studies detailed in the Stipulation Monitoring Report.
1. Minimal training
Training for use of these cameras took less than 15 minutes. This was ideal for our team of mostly volunteers.
2. GPS-record the locations photographs were taken
The accuracy of this location is approximately 2-5 m. While this is not as accurate a location as the Trimble GPS units could record, it is sufficient for the Team’s purposes. The cameras do have the ability to record the location of the object photographed rather than the location of where the photograph was taken, however, the Team did not require this capability.
3. Record information about each photograph
Caplio’s List Editor software (which ships free with the camera) was used to create a data dictionary to ensure all information was collected in a standard way. Outlined below are the possible entries accessed via drop-down menus for each of the 5 data fields.
Field: Representative attribute values
Study: Art Project, Perimeter Fence, Trash transects
Stipulation: 19 – Art Burn, 32 – Perimeter Fence, 79 – Trash
Status: Good/Stip Met, Bad/Concern, Ugly/Violation, Other
First Digit: 1st digit of trash transect number (0-9)
Second Digit: 2nd digit of trash transect number (0-9) 
4. Watermark photos with entered information
GPL-Photo Link generates a watermarked version of the photograph, which can be customized to display items such as -
Title
Comment
Location taken
File name
Date and time
Or any of the 5 entered attributes
5. Transfer data to ArcGIS
GPL-Photo Link also generates a shapefile, a common ArcGIS file format.
6. Field-worthy
Despite extreme temperatures and a brutal amount of alkaline playa dust, these cameras have continued to survive multiple Burning Man events, as well a year-round use for other projects including hundreds of miles of route inventories on ATVs and motorcycles.
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Software: Geospatial Experts GPS-Photo Link |
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The software works with any digital camera and GPS
All digital photos and all GPS-collected positions contain the common element of date and time. GPS-Photo Link software uses this common time element to "link" digital photos to GPS positions.
GPS-Photo Link generates 1) watermarked copies of the photos displaying the coordinates of the photo location the photo and other attributes, 2) ESRI shapefiles or a geodatabase feature classes for display of photo locations and hyperlinks to the images, and the management of digital photos spatially, and 3) for non-ArcGIS users, other GIS formats such as .mkml for Google Earth.
A camera with onboard GPS is highly recommended since the gps coordinates and custom attributes entered via the camera back are written directly to the digital image file as the photo is taken. This greatly simplifies getting processing and file management. There is no longer a need to synchronize camera and GPS time. It also eliminates the need to fret over which camera files go with which GPS files - a serious consideration with multiple teams, field sesions or pieces of equipment.
ArcGIS is not necesary to use GPS-Photo Link. The software produces Google .kml files and and other common GIS formats.
See www.geospatialexperts.com for product details.
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Software: WindImage for ArcMap |
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WindImage is an option for those using a GPS camera & ArcGIS
The software generates watermarked copies of the photos displaying the coordinates of the location the photo was taken, ArcGIS shapefiles or a geodatabase feature classes for display of photo locations and hyperlinks to the images. Photos can also be stored in the database direcly, or file names captured in a feature clas with links to images saved outside the geodatabse.
See http://www.windenvironmental.com for product details.
See www.elecdata.com/gps/Photo_Linking_Software_Comparison.pdf for a comparision of GPS-Photo Link and WindImage software options. |
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