In principle, any data projector with a resolution of 1400 x 1050 can be used for HDAV presentations. Those who make very high demands to sharpness, brilliance and color rendering should go for projectors with a resolution of 1920 x 1080 pixels or 1920 x 1200 pixels, respectively. For lecture halls Canon XEED models have proven their worth as they are very bright and offer a good price-performance ratio. Those who do not want to spend so much money will also find a few interesting models among home cinema video projectors, which are available at prices starting from Euro 1,000.-- but which can only be used for image widths of up to about 2 m. It is important to know that many video projectors have been designed for computer and business presentations (PowerPoint, etc.) and focus on brightness instead of true-to-nature, photorealistic image representation. Home cinema projectors are slightly better when it comes to image representation, but very often they do not have the necessary brightness. Moreover, they usually feature an image chip with a 16:9 format, which may prove an inspiration for your creativity, but would mean inefficient utilization of the resolution for 4 : 3 pictures.
In the meantime affordable 4K projectors for home cinema applications have arrived on the market which, however, are not bright enough for lecture halls. 4K projectors with a brighness of 5000 lumens or up are still quite expensive and cost EUR 30,000,-- and more (May 2017).
Try to get as much advice as possible from HDAV dealers and test the video projectors with your own shows. Always use presentation data at a resolution that corresponds to the physical video projector resolution to avoid interpolation loss.
See also
Signal processing and connectors