"ACE24" Convertor Controls

Front View of ACE, Showing Controls. File Size 41k

8Mbit Memory. Timebase Corrector. Full 4:2:2 True "S" Processing

INTRODUCTION

The ACE24 Video to Film Rate Convertor is designed to allow filming of TVs on movie film sets without flicker by synchronising the TV and film camera. ACE24 can be connected between any world video source and any TV capable of displaying 625 line 48 fields/second pictures, which means almost all NTSC TVs and most PAL TVs. Mains powered via a plug top adaptor, ACE24 can be used for colour correction of on-set TVs with or without conversion to the film rate of 24fps. When converting it offers variable vertical size and position to compensate for the behaviour of TVs when handling this unusual frame rate. It comes with Freeze Frame and 3200k colour temperature compensation settings but can also be fitted with many of our normal Special Versions. There are two Master Sync outputs which can be used to synchronise film cameras or to feed the Slave Sync input of other ACE24s so that all are locked together at 24fps regardless of the video sources.

The following descriptions explain the main purpose of each control and there is also a 'Useful Tips' section in the Instruction Manual where some interesting and useful combinations are suggested. Please see the Performance and Specifications page for full technical details of performance and connections.

Click on any Control Group in the Picture Above to go Directly to its Description.

Fade/Standard Controls:

STANDARD: These four push buttons control the operating mode of the ACE24 Convertor. Conversion options, Timebase Correction and even a Direct Mode where Output Standard automatically matches Input Standard (for colour correction without conversion) are available. Converted Output Standards are set using the four push buttons as shown in the table (input standard setting is automatic):
Please note the ACE24 Convertor automatically senses the input standards and you only need to set the output standard.

Format	Version	Fields	Colour	STANDARD		STANDARD
Format	Version	Fields	Colour	PAL	NTSC	60	3.58
PAL	Slow PAL	48Hz	4.43MHz	IN	OUT	OUT	OUT
PAL	Slow PAL	48Hz	3.58MHz	IN	OUT	OUT	IN
NTSC	Slow NTSC	48Hz	3.58MHz	OUT	IN	OUT	IN
NTSC	Slow NTSC	48Hz	4.43MHz	OUT	IN	OUT	OUT
SECAM	Slo SECAM	48Hz	4MHz FM	IN	IN	Any Position

FADE: This button initiates an Automatic Fade in about 1 second. Pressing it IN will cause the picture to fade to black. Releasing the button to OUT will cause the picture to be restored by a reverse fade.

FREEZE: When Pressed IN this button holds the last two fields captured. By default these two fields are averaged and the result displayed for both output fields to avoid motion flicker. However the INVERT OPTION button allows you to cycle through four display modes: Both Fields Averaged & Repeated / Both Fields Displayed in sequence / Field 1 Repeated / Field 2 Repeated. We suggest you simply select a mode by eye for the best results, noting that when both input fields are shown in sequence there may be motion jitter. This changes to a static motion blur when both fields are averaged.

3200K: When Pressed IN this button selects a fixed colour correction to convert the normal TV colour temperature of around 5500K to 3200K. White Balance controls are disabled.

V POSITION: This is used in conjunction with the V SIZE control and adjusts the vertical position over the full TV screen height when image size has been reduced. This will help compensate for vertical positioning errors when NTSC or PAL TVs are used with 48Hz scanning when they are likely to overscan.

Colour Controls:

SATURATION: This control allows you to adjust the level of colour in the picture from zero, i.e. Black and White only, up to twice the normal colour level.

BALANCE: This control alters the colour balance of coloured areas without affecting white balance and is especially useful for correcting any residual faults in skin tone when white balance has been corrected. This is important as White Balance alone does NOT cure All colour faults. The ACEs are unique in offering both.
NOTE: When the video input source is NTSC this control automatically acts as a HUE control.

<-SHIFT->: After recording and video processing you will often find that the colour seems to 'bleed' out of the coloured areas. This is caused by faults in the video processing which can move the colour sideways compared to the black and white parts of the picture and is particularly evident with multiple generation copies. This control allows the colour part of the picture to be moved horizontally left and right to line up the colour properly and eliminate the colour bleed.
Vertical Colour Shift is provided by the COLOUR SHIFT ^ Control to cure colour droop.

White Balance:

RED, GREEN and BLUE: These controls affect the colour of the white areas and all of the lighter parts of the picture. They allow correction of white balance colour faults caused when a video camera does not properly compensate for colour of lighting, to match video from different cameras or to convert video to match film lighting conditions (please also see the 3200K fixed setting control described above). Contrast, brightness and colour saturation are not affected. These controls can also be used creatively to add tints, create sepia effects etc. or to create blank screens of almost any colour as fully described in the ACE24 Instruction Manual.

Video Controls:

CONTRAST & BRIGHTNESS: These operate like those on your TV except that they probably have a wider range. Together they can correct many exposure faults and help create a wide variety of special effects.

Special Effects:

SHARPNESS: This control allows the sharpness, or detail, of the picture to be corrected to compensate for losses in copying etc. A wide range of Both Boost and Cut are provided to cover all eventualities. On the ACE24 this control gives a beautifully symmetrical improvement to the sharpness of edges, unlike some units.

V SIZE: This is the only rotary control which should normally be set nearly fully clockwise at about the 3 o’clock position (6th step out of 7) as this is the position in which it has no effect on the picture height. At the minimum setting the image height will be reduced by 3/4. This is intended to compensate for overscanning of TVs when operated at 48Hz. The V SIZE control will allow the image to be expanded vertically in 6 steps of 5.5% back up to full height and at the 7th position to overscan. When the V SIZE control is set below position 6 of the possible 7 steps the V POSITION control can be used to move the image vertically over the available output height range to allow images to be correctly centred.

Left Hand Push Buttons:

BYPASS: Depressing this button cancels ALL control settings except INPUT SELECT, STANDARDS, FREEZE, V SIZE and V POSITION. Pressing this button IN allows you to compare the effects you create to the original i.e. ‘Before’ and ‘After’ processing. NOTE: The Red LED on the ACE24 indicates "Sync Present".

INVERT OPTION: Pressing this button allows you to cycle through the options in order: Normal / Negative / Colour Invert / Video Invert. In Negative Mode it is possible to view colour negatives, assuming you have a slide converter and film strip holder or can improvise. With Colour Inverted, green turns into purple, blue into yellow and skin tone a ghastly blue colour. Ideal to turn people into monsters! With Video Inverted, black parts of the picture go white and vice-versa. With Normal Colour this can have a quite pleasing but spooky effect. NOTE: This becomes the Display Mode control in Freeze Frame and on the "M" Special Version in non-freeze frame mode it controls Left/Right Mirror Imaging. (See Special Versions Page)

COLOUR SHIFT ^: Pressing this button allows you to cycle through the Vertical Colour Shift range of 0 to +3 lines and back to 0, to get rid of 'colour droop' often resulting after several generations of copying.

Right Hand Push Buttons:

TEST SELECT: Pressing this button allows you to cycle through the test patterns in order: Normal/Colour Bars/Blue Screen/Red Screen. The Broadcast standard Colour Bar Test Pattern and the Red and Blue Blank Screens can be used to check your own equipment performance or to check your TV’s Contrast, Brightness and Colour Saturation settings before filming.

OUTPUT TYPE: Pressing this button allows you to cycle through 4 output combinations on the "S" Video Output & SCART Connectors, allowing access to "S" or Dual Composite Video on the "S" Output Socket and to RGB or YUV on the SCART Socket.

POWER: The operation of this button will come as no surprise. It must be IN for normal operation!

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