3. Physical Installation
SCREEN
DMD
Lp1
Lp2
Fp1
Fp2
SCREEN
DMD
Lp3
Lp4
Fp3
Fp4
(Scheimpflug)
Image 3-5
Scheimpflug principle
Scheimpflug principle
The "plane of sharp focus" can be changed so that any plane ca n be brought into sharp focus. When the DMD plane
and lens plane are parallel, the plane of sharp focus will als o be parallel to these two planes. If, h owever, the lens
plane is tilted with respect to the D MD plane, the plane of sharp focus will also be tilted ac cord
ing to geom etrical and
optical properties. The DMD plane, the principal lens plane and the sharp focus plane will intersect in a line be low the
projector for downward lens tilt.
Scheimpflug adjustment points
Scheimp flug adjustment points are located on the lens mount. The F 70 has three (3) set screws and three (3) adjustment screws.
When to apply Scheimpflug?
Scheimpflug c orrection procedures may only be carried out by su itably trained and experienced t echnicians.
A Scheimpflug correction should only be applied wh en the overall focus of the projected image is not equally sharp (for example, if the
projector is NOT in parallel with the screen or as a result of a previously misaligned Sc heimpflug). Be aware that the consequence of
applying Scheimpflug correction upon a s creen not in parallel w ith the projector is that the projected image differs from the rectangle
shaped image. In other words “distortion” of the projected image occurs. Masking will be required to solve the distortion.
The disadvantage of Masking is loss of content. Therefore it is st rongly recomm ended to place the projector in parallel with the
projection screen and us e the SHIFT functionality of the Lens Holder to match the projected image with the projection screen. If the
SHIFT range is not sufficient then the projector can be tilted and Scheimpflu g can be applied.
3.9 Scheimpflug adjustment procedure
CAUTION: A Scheimpflug adjustment should only be carried out by properly qualified and experienced pro -
jection specialists. A poor Scheimpflug adjustment may result in an extremely degraded image and will require
factory—servicing to the projector.
Necessary tools
• Allen key, hex size 4
• Allen key, hex size 6
Preparation
1. Prepare the test area. Barco recommends a projector-screen distance of 2 m etres be used for all Scheimpflug adjustments.
Verify that the throw r atio of the installed lens matches the requirements of the installation area (projection distance and screen
size).
2. Check that the lens is correctly installed, and lens shift is in centre position.
3. If the installed lens ha s Iris control, op en the Iris all the way up.
4. Open the focus ring all the way up.
5. Go to Main M enu / Test Patterns / Full Sc reen and select to display the Focus test pattern.
6. Zoom the lens to its widest opening (max imum image size on the screen).
601–0442 BALDER 13/09/2017
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