High Resolution Geo-referenced Photographing

Ricoh Caplio 500SE

Recently Ricoh unveiled their latest digital camera; the Ricoh Caplio 500SE. Since it is not the custom of this magazine to review photographic products, there must be something ‘geo’ about it. And there is; the camera can connect to a GPS receiver, store position information with the photograph and then export it to Google Earth or GIS package.

By Huibert-Jan Lekkerkerk

Ricoh Caplio 500SE and Fortuna Slim Bluetooth GPS.

Review Set-up

Since I’m an amateur photographer as well as a writer on positioning, reviewing this camera was something I truly enjoyed. The price of the camera is steep, with the European distributor, Alta4, quoting a price of EUR 696 excluding VAT. A ‘mouse’ type GPS receiver (Fortuna Slim Bluetooth GPS) was delivered with the camera. This receiver has the latest SirfStar III GPS chipset, creating a very sensitive GPS receiver with Bluetooth communication and 20 parallel GPS channels. The camera was tested on two separate occasions; one during a walk in a nature reserve and the other during a boat-cruise on the New Waterway in Rotterdam, the Netherlands.

Watertight

Ricoh states that the camera is watertight to IP67 specifications (up to 1 m water depth), that it is dustproof to JIS grade 6 and that it can be dropped from a height of one meter without sustaining damage. Due to the water tightness the camera looks a bit cheap with its rubber body and soft plastic keys. Having said that, it feels quite sturdy and seems to be more than up to the tough life of everyday surveying. The supplied GPS receiver however was neither watertight nor dustproof. But the camera can be coupled to any GPS receiver capable of outputting NMEA type GPS messages, so just hook it up to your trusted GPS solution. There seems to be a design flaw with the see-through seeker. And although most people will probably prefer the LCD display on the back of the camera for composing the picture it can become unreadable in bright sunlight. The built-in see-trough seeker is however obstructed by the camera housing at wide zoom angles.

Image Sensor

Contrary to what most camera manufacturers want you to believe, there is more to image quality than just the resolution. The quality of the image chip and the lens in front of it play a large role as well. As stated, the resolution of the camera is high enough. The chip itself is however a bit noisy. This manifests itself under darker conditions or when photographing dark objects. The effect becomes more pronounced with the camera in ‘anti-blur’ mode where it increases the sensitivity of the sensor. This is however not particular to this camera alone.

Taking Photographs

Taking photographs is as simple as with any other camera; just point and shoot. Most settings in the camera are made automatically; it is not possible to manually set either shutter speed or diaphragm. There are however a few specialized programs that manipulate the way the camera operates. One does need to consider the so-called shutter delay when photographing. When pressing the shutter release button fully down there is approximately a one second delay before the photo is taken. Pressing the shutter release button halfway down and letting the camera focus before taking the photography makes the delay negligible. Some peculiar setting called CALS can be found on the main mode selector. If set to this mode, the camera reverts to 1.3 Mega Pixel resolution, which seems to be a Japanese requirement for pictures taken of civil constructions.

GPS Connection

The GPS receiver and its connection to the camera work perfectly. The camera can be set to automatically look for the GPS receiver on the Bluetooth connection during start-up. One minor problem I encountered was where to mount the GPS receiver. This was quickly solved using some tie wraps to strap it to my photo bag. When using a survey grade GPS receiver this will be a lesser problem since the GPS can be mounted on a pole. The number of GPS satellites and the position can be displayed on the LCD screen in a few different coordinate systems. Available is of course latitude and longitude as well as Universal Transverse Mercator and it’s militarised version, MGRS. The number of available geodetic datums is however disappointing with only WGS84 and Tokyo datum as options. The coordinates systems are only applicable to the display since all positions are stored in WGS84 latitude and longitude in the metadata (EXIF) of the JPEG image.

Geo-referenced photograph of the Shipping and Transport College (Rotterdam, Netherlands) in Google Earth.

Bundled with the camera were two software packages. One is the basic software suite common to all digital camera’s, containing a photo management solution, an editor and a tool to burn disks and create all sorts of photo-related printings. The second package, Fodysseus, is of more interest to this review. It is a simple tool that reads the position information from the EXIF and transforms it into a KML file that can in turn be read by Google Earth or a GIS package. Another option is of course to use a GIS package that can extract the position from the EXIF information. Alta4 provides the GPS Photomapper software, which integrates into ArcMap for that purpose. The latter was however not tested in this review.

Displaying Photographs

For the test I shot a number of photographs. At home I processed the photographs using my own favourite photo editor (Adobe Photoshop). This is no problem since the more advanced photo editing packages leave all the EXIF information, including the position information, intact. The photographs were then transformed to a KML file, which was subsequently displayed in Google Earth. One disadvantage is though that no heading information other than the GPS heading is available. Since this is only accurate when moving in the same direction as shooting the photograph, most photos contained a heading that was not representative of the direction onto which the photo was taken. Google Earth uses this heading however in it’s display, especially when multiple photos are taken at the same location. With GPS Photomapper the user supposedly can adjust the heading manually, but the best would be to include a small digital compass with either the GPS unit or with the camera.

Pro in Day-to-day Surveying

Due to its robustness and Bluetooth communication ability, which is a pro in day-to-day surveying, the price of the Ricoh is steep when compared to other, equivalent, digital cameras. Some aspects of the camera were slightly disappointing but overall the camera can be a good addition to a GIS surveyor’s equipment. What would truly improve the usability of the camera is the inclusion of a small digital compass for heading reference. Alta4 has promised that a clip-on GPS unit with compass will become available in the second quarter of 2007 for a price of around EUR 200.

Huibert-Jan Lekkerkerk (hlekkerkerk@geoinformatics.com) is freelance writer and trainer in the field of positioning and  hydrography. For more information go to: www.ricoh.com (camera) and  www.fortuna.com.tw (gps). To find out more about the Alta4 products: www.alta4.com.