Many clubs are now keen to show digital images as part of presentations or for competitions. In this section we discuss some of the issues that you may face and include experience from some clubs that have already taken the plunge.
You will need a data projector and a laptop computer for holding the images.
Data projectors cost from well under £1000 to £1700 for those of a suitable quality. Spare lamps cost £300 to £400, although they normally last 1000 to 2000 hours depending on make. Most laptop computers are adequate for this purpose so a budget of about £900 should be adequate. Finally, software costs can range from next to nothing up to several hundred pounds depending on what you wish to do.
A number of clubs have made bids to the Lottery Fund Awards for All. They provide funding from £500 to £5000 for small projects. In the London area (including Bromley and Croydon) they are looking for projects that: benefit those with economic hardship, ethnic minorities, the disabled or help communities explore and share their heritage and London's diverse culture and traditions. Elsewhere in the South East the focus is broader including support for arts, heritage and other community activity. In some cases your local Council may provide support in applying for such awards.Top
Resolution: You should choose a projector having a native resolution of at least 1024 x 768 pixels (so-called XGA). Lower resolution projectors can sometimes convert from 800 x 600 pixels (so-call SVGA) to a higher figure, but such interpolation is not suitable for good quality image projection. There are now a number of SXGA+ format projectors available with a native resolution of about 1400 x 1024 pixels. Both DLP and LCOS versions exist (seeTechnology below) but their price is currently about £2700. There are also an increasing number of widescreen projectors intended for home cinema purposes. These normally are a maximum of 720 or 768 pixels high so offer no real advantage over XGA format projectors for most photographic work.
Dead pixels: Most projectors do not have dead pixels (ones that are permanently white, black or a primary colour), but manufacturers usually state that they consider a few dead pixels to be acceptable. One club managed to persuade their supplier to replace a projector that had a couple of dead pixels on delivery - they are not obliged to, but it might work.
Technology: There are two competing technologies for affordable digital projectors: LCD (Liquid Crystal Display) and DLP (Digital Light Processing). With LCD light is shone through three panels for R, G and B, and pixels are turned on and off to form the image. DLP is Texas Instruments technology and essentially consists of tiny mirrors where R, G and B light is alternately shone on to these and reflected on to the screen. DLP devices tend to have higher light output, but a few people can see "rainbow" effects with them due to the alternating R, G, B light. This is rare and is more of a problem with moving images when they are used for home cinema.
LCD image quality can degrade after 1500 or more hours of use particularly in the blue panel (at least three years at 10 hours use per week). Competition between the rival technologies probably means that there is not much to choose between them, although DLP is generally lighter(weight) and possibly cheaper.
Canon have their own LCoS (Liquid Crystal on Silicon) technology that has virtually no 'barn door' effect (black around pixels) so produces a very smooth clean image. Prices start at about £2000 for the Canon SX600 (1024 x 768), compared to a very good DLP projector (Optoma DX733) costing about £700 - April 2007 prices.
See Evan Powell's article for an excellent review of the issues.
Light Output: A couple of years ago the light output of projectors was typically about 1000 lumens. Now, many current models produce 2000 lumens or even more. Anything greater than about 1100 lumens will do a good job in normal club surroundings on a 6 foot screen. Some DLP projectors can produce 3000 lumens or more and these can sometimes be too bright for viewing in darkened conditions.
Contrast Ratio: Current projectors claim 450:1 contrast ratio or higher. Higher values produce the best shadow:highlight differentiation. However, even though these projectors are bright, to see good photographic detail it is always necessary to use a dark room. DLP and LCOS projectors give the best ratios - up to 2000:1 in some cases, but this is only achieved in full blackout conditions.Top
Lens: Data projectors generally have non-interchangeable zoom lenses. To fill a 2 metre screen the projector will typically only need to be about 3.5 m away, perhaps about half the distance of a 35mm slide projector. Data projectors usually have keystone correction facilities built in.
Aspect Ratio: The standard aspect ratio is 4:3 horizontal:vertical. Some wide screen projectors are now appearing but they seem to be targeted at the home cinema market.
Lamp Life: In most cases this will be for about 2000 hours. The projector keeps track of use and some prevent use beyond the stated life. Since lamps cost about £300 its worth checking the lamp life figure. Hitachi has been including 3 year lamp warranty with its projectors. With some of the brighter projectors there is often an economy mode that produces plenty of light for photographic images in darkened rooms and extends the nominal life of the lamp from perhaps 3000 hours to 5000 in some cases.
Connection: Data projectors are usually connected to the laptop using a 15 way analogue VGA cable (blue connector). The one provided is usually about a metre long. A 7.5 m Extension cable costs less than £20. If you need a longer distance than that between laptop and projector you should consider a wireless link. Selsdon CC have a wireless connection that works well, although there is a slight delay when images are changed.
Newer projectors usually come with a DVI connector (white connector). This is the preferred connection method if your computer has one of these too.
Screen: In most cases existing screens for slide projection are fine, but some beaded screens can produce Moire patterns with a data projector.
Cable Management: Rubber cable covers to prevent people tripping over them can be obtained in 1 metre or 3 metre lengths. Staples (on-line ordering look under "cable covers") are competitive.
Helpful Companies: Various people have found the following companies helpful:
ProjectorPoint: Based at Richmond. Have a very wide range and are very helpful on the phone. Very competitive prices. Web: www.projectorpoint.co.uk Phone: 0800 073 0833
Hocken AV: Based at Kingswood. Very helpful. Web: www.hockenav.co.uk Phone: 01737 370371
Pinnerton: Based in Woking. Very helpful. Web: www.pinnerton.co.uk Phone: 01276 488111
If you have found a particularly helpful company when you were purchasing a digital projector or related equipment, please let me know so we can add their details here.Top
Purpose: It is worth trying to anticipate the uses to which the equipment will be put. Some clubs have been interested in using the laptop for Digital Imaging demonstrations as well as image display for competitions. A higher specification computer is needed in that case. Other clubs (Selsdon CC) have been keen to run international competitions and to send CDs or DVDs of the competition, complete with judges commentary to the other clubs involved.
Laptop: Generally laptops are chosen as they are more convenient to transport. Mac or PC laptops are equally useful and the choice really depends on the preferences of club members and budget.
Main Memory: Most machines these days have at least 256MB (megabytes) of main memory, but if you are planning to use it for Photoshop demonstrations too it is best to increase it to 512MB or 1GB (gigabyte).
Hard Disk: Images for competitions will be relatively small so disk space will not be an issue, but if using Photoshop do not go for less than 40GB of hard disk space.Top
CD/DVD: It is worth getting an internal CD/DVD writer with the machine to allow exchange of data with others and for backing up. A free-standing external drive (USB2) costs about £150, similar to the cost of a built-in one. The choice depends on whether the CD/DVD drive is to be shared among several machines.
Keyboard/mouse: One way of reducing the cabling problems is to keep the laptop close to the projector and have a cordless keyboard and mouse so that the demonstration/competition can be controlled remotely. Standard wireless mice and keyboards work well, but their range is limited to about 5-6 feet. "Bluetooth" keyboards and mice claim a range of up to about 30 feet, but they are more expensive. (Don't forget spare batteries!)
Audio: Small PA systems with radio microphones are available for £200-£300. Selsdon bought theirs from Sound Dynamics Ltd.
Display Connector: If possible, choose a machine that has both DVI and VGA connectors for attaching a display or projector. The DVI connector should give (slightly) better image quality.Top
The package that has been used in FSLPS Competitions such as Jack's Jug and the Vic Smith Trophy is DiCentra. It is costs £35 for a club licence. It provides facilities for loading images from entrants and checking that they comply with the competition rules. Facilities are provided for setting up the projector prior to judging. Marks are accumulated during the competition and selected images can be held back to be marked at the end. The scoresheet can be displayed at any stage and a 'Lightbox' can be used to select images for awards.
Some people use MS Powerpoint for producing presentations, although it is relatively expensive if used just for that purpose. There are many other packages including PicturesToExe for about $30.
Slide shows can also be made with Photoshop and displayed in a browser such as Internet Explorer.