signal. Unlike the locked mode(s), the iScan’s output signal timing will not be disrupted when the input source is changed. However, it’s guaranteed to cause dropped or repeated frames as the input and output frame rates are not the same. Note that regardless of what number the unlocked output frame rate is set to, it will never be identical to the input rate in this mode as the output signal timing is independent of the input timing. These dropped/repeated frames can result in visible irregularities in smooth motion, sometimes called motion judder or stutter.

Locked mode (2:2 or 3:3): For standard definition interlaced sources the iScan can detect 2:2 and 3:2 pulldown cadences and convert these to either a 2:2 or 3:3 frame repetition rate. The main advantage of this is for 60 Hz sources using 3:2 pulldown, as the irregular 3:2 pattern can be converted to 2:2 at 48 Hz or 3:3 at 72 Hz. In these modes, each original film frame is repeated exactly 2 or 3 times, respectively, and motion is therefore smoother. Note that these modes are only useful when the video source is film-based — i.e., 3:2 pulldown for 24 Hz film on 60 Hz sources, and 2:2 pulldown for 25 Hz film on 50 Hz sources. If the source is not film-based, then the end result is a lot like unlocked mode without that mode’s stability advantages.

Motion-judder test pattern: The iScan has a built-in test pattern generator to help you deter- mine which frame rates your display supports. This is the test pattern with the vertical bar which pans horizontally back and forth across the screen. Note that this test pattern is used to determine the capabilities of your display, and does not provide any indication of motion smoothness (or lack thereof) in the iScan’s output. The test pattern is used with the unlocked output mode of the iScan. You set the (unlocked) output frame rate to be the one you’re testing your display for, and observe if the back and forth panning motion of the test pattern is smooth or if it jerks or stutters. If the former, then the display supports that particular resolution and frame rate without perform- ing any frame rate conversion of its own; if the latter, then the display is performing frame rate conversion on the signal.

Examples. These configuration options provide a lot of flexibility to deal with differing source and display characteristics. Let’s look at a few examples:

A.The display only supports 60 Hz input. In this case, the iScan must produce a (nominal) 60 Hz output. For 60 Hz sources you can run in either 1:1 source-locked mode, or

in unlocked mode with the output frame rate set to approximately 60 Hz. You might choose unlocked mode if the display takes a long time to re-sync to new inputs and you channel-surf a lot. Locked mode will provide the smoothest motion and guaran- tee no dropped or repeated frames. For 50 Hz sources, you’d set the iScan’s output to unlocked with a (nominal) 60 Hz frame rate. This will result in some motion irregularities as the iScan periodically repeats frames to convert the 50 Hz input to the 60 Hz output rate, but since the display only supports 60 Hz inputs there’s not much you can do.

B.The display only supports 50 Hz input. This is the opposite of case A, and the required configuration is also the opposite — i.e., the output frame rate for 60 Hz source should be set to 50 Hz unlocked, and the rate for 50 Hz sources can be set to either 1:1 locked or unlocked at 50 Hz (for all the same reasons noted in the first example).

C.The display supports a wide range of frame rates (e.g., a front projector). In this case you can configure things most any way you like. If motion judder with 3:2 pulldown bothers you, then use the iScan’s 24Hz, 48 Hz or 72 Hz source-locked output options for film-based 480i sources. If not, then 60 Hz locked is a good choice. For 50 Hz sources, unless you notice display flicker at 50 Hz, you’d probably want to run at 50 Hz locked to avoid repeated/dropped frames.

D.A digital display supports a narrow range of frame rates, either around 50 Hz or 72/75 Hz. If the display supports both 50 Hz and 48 Hz, and the primary use of 60 Hz source is film-based material, then you would likely want to configure the iScan as 48 Hz

source-locked for 60 Hz sources, and 50 Hz locked (or unlocked, if desired) for 50 Hz sources. If the higher frame rate (72/75) is desired or required, then both source types can be config- ured for the 3:3 source-locked output option. For non-film material you may find that there’s too much motion stutter, although that tends to be a very personal thing as not everyone perceives this the same way (as with low frame rate display flicker).

Border Level

The border level setting is global, that is, there is only one border level setting for the system. To adjust the border level, push the P or Q button. The current level is shown. The default value is ‘0’. Push the P or Q button to decrease or increase the border level.

Picture Controls

The iScan VP50PRO has picture memories for each accepted format that are automatically saved and recalled on each input. In addition to these controls, the iScan VP50PRO has output picture controls that can be used for multiple applications. One application is to save two separate output modes for day/night usage where the ambient light changes. Another application is two adjust the output for separate connected displays. There are two user modes available, titled ‘Preset 1’ and ‘Preset 2’. To make adjustments to one of these modes, first select the desired mode in the ‘Preset’ submenu and then make the desired changes to the Output Picture Controls.

These modes can be recalled using the Viewing Modes button on the remote control.

There are also three additional modes which can be saved by a calibrator who has been trained by the Imaging Science Foundation on proper display calibration methodology. These modes are titled ‘ISF Day Normal’, ‘ISF Day Bright’ and ‘ISF Night’.

More information about the Imaging Science Foundation is available at www.imagingscience.com

HDCP Mode

There are two HDCP modes:

Off: HDCP is disabled at the iScan VP50PRO’s HDMI output.

On: The iScan VP50PRO continuously looks for a HDCP display device on its HDMI output. This is the default setting.

NOTE: The iScan VP50PRO is not designed to remove HDCP from a protected signal. If this setting is set to ‘On’ make sure that the corresponding HDCP Mode setting on the input is also set to ‘On’.

12V Triggers

The two 12-volt trigger ports are designed to supply a combined total of 500mA which is split between the two devices based on their draw, so one device can draw up to 495mA if the other only draws 5mA — or both can draw 250mA. These devices do not need to have the same current draw to work. This is enough current to drive one or two 12-volt relays, suitable for turning on a lens and projector, for example. If the combined draw exceeds 500mA, the video processor is protected against over- load. The state of the 12V triggers can individually be adjusted in the ‘Configuration’ menu. This is helpful if the default state of the connected device is incorrect. For example a screen may be set to go up, when in fact the desired state for the screen is to be down.

When the Trigger Level is set to “Normal”, it will supply +12vdc on the TIP when active, and will pull the TIP to Ground (0vdc), referenced to the SHIELD — when inactive. When the trigger port is set to “Negative”, it will pull the TIP to Ground (0vdc), referenced to SHIELD — and will supply +12vdc to the TIP when inactive. The SHEILD will never carry the +12vdc supply signal. To ensure that damage is not caused, please check the manual of the device that you intend on connecting to the VP50PRO before inserting the trigger plug into the jack.

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DVDO VP50 owner manual Border Level, Picture Controls, 12V Triggers