3
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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 Vp50
pro
has picture memories for each accepted format that are automatically saved and
recalled on each input. in addition to these controls, the iscan Vp50
pro
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 ’ 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 Vp50
pro
’s HdMi output.
• On: The iscan Vp50
pro
continuously looks for a HdCp display device on its HdMi output.
This is the default setting.
NOTE: The iscan Vp50
pro
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 2-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 2-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 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 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 Vp50
pro
before inserting the trigger plug into the jack.
