Projector Thunderdome: Variable Lens Shifting vs Keystone Correction

[Leecher]

Variable lens shifting is no longer limited to ultra-high end projectors. Projectors like the Panasonic PT-AX100U, and PT-AE900U along with the Epson Pro Cinema 800, Hitachi PJTX100 and a couple lower-end models from Sanyo are including variable lens shifting.
Hit the jump to learn the difference between variable lens shifting and its evil nemesis, Digital Keystone Correction and see which one reigns supreme in the Thunderdome.

Keystoning is when a projector is long lined up completely straight with a wall and creates a less than perfect rectangle and looks more like a trapezoid. Some projectors try to correct for this with Digital Keystone Correction. This correction process compresses the "fat end" of the keystone, or trapezoid, therefore lowering the quality. It wouldn't be very noticeable with a Powerpoint presentation, but it can be significantly noticeable with video or high resolution pictures.
The other option to correct non-perfectly mounted projectors is variable lens shifting. Most projectors already have a limited amount of lens shifting, but for the most convenience you want a variable lens shift that can move any direction while still maintaining a rectangular image (see video above).
Luckily, variable lens shifting is now becoming available on home theatre projectors that don't cost an arm and a leg. Most of the projectors ranging around $2,000 to $3,000, which is fairly reasonable for a home theatre projector.
The Bottom Line
If you are looking at projectors for a home theatre, avoid projectors with Digital Keystone Correction and go with the variable lens shifting—it will look a lot better if you have to mount above or below the desired projected area. – Travis Hudson
Some keystone information via ProjectorNews

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