Connectivity: Camera System: Glossary: Learn: Digital Photography Review

Learn : Glossary : Camera System : Connectivity

Connectivity
By Vincent Bockaert

A digital camera's connectivity defines how it can be connected to other devices for the transfer, viewing, or printing of images, and to use the camera for remote capture.

Image Transfer

Early digital cameras used slow RS232 (serial) connections to transfer images to your computer. Most digital cameras now feature USB 1.1 connectivity, with higher end models offering USB 2.0 and FireWire (IEEE 1394) connectivity. Manufacturers generally bundle such cameras with cables and driver software.
Note that real transfer rates are always lower than the theoretical transfer rates indicated in the table below. Practical transfer speeds depend on your computer hardware and software configuration, the type of camera or reader, the type and quality of the storage card, whether you are reading or writing (reading is faster than writing), the average file size (a few large files transfer faster than many small ones), etc.
Instead of connecting the camera with a cable to your computer you can also insert the storage card into the PC Card slot of your notebook or a dedicated card-reader.

Theoretical Transfer Speeds	Transfer Rate
USB 2.0 - Low-Speed = USB 1.1 Minimum		1.5 Mbps
USB 2.0 - Full-Speed = USB 1.1 Maximum		12 Mbps
USB 2.0 - High-Speed		480 Mbps
FireWire/IEEE1394		100-400 Mbps
Practical Transfer Speeds	Approx. Transfer Rate
Digital Camera USB 1.1		~ 350 KB/s
Digital Camera FireWire		~ 500 KB/s
USB 1.1 Card Reader	~ 900 KB/s	~ 7 Mbps
PC/PCMCIA Card Slot on notebook	~ 1,300 KB/s	~ 10 Mbps
USB 2.0 or FireWire Card Reader	~ 3,200 KB/s	~ 25 Mbps

A transfer rate of 1 Megabit per second (Mbps) equals 128 Kilobytes per second (KB/s) and is able to transfer 7.5 Megabytes of information per minute or about four 5 megapixel JPEG images.

Remote Capture

On some cameras, the connection to transfer images can also be used for remote capture and time lapse applications.

Video Output

Most digital cameras also provide video (and sometimes audio) output for connection to a TV or VCR. More flexible cameras allow you to switch output between the PAL and NTSC video standards. Cameras with infrared remote controls make it easy to do slideshows for friends and family from the comfort of your armchair.

Print Output

Some digital cameras, e.g. those with PictBridge and USB Direct Print support, allow you to print images directly from the camera to an enabled printer via a USB cable without the need for a computer. Although printing directly from a digital camera is convenient, it eliminates one of the key benefits of digital imaging—the ability to edit and optimize your images.

This article is written by Vincent Bockaert,
author of The 123 of digital imaging Interactive Learning Suite
Click here to visit 123di.com

Learn : Glossary : Camera System : Connectivity