Using MegaShapes to create vignettes

Full screen vignettes can be created using the circles tool. To help with this, there are several useful notes in the "MegaShapes" project under the Pandora user.

Recall the appropriate note, depending on whether the system is 525, 625 or 2K, and press the 'Show' key. From this it can be seen that they contain a full-screen soft edged circle in the green channel. The green channel can now be used to adjust the centre of the picture, and the blue channel can be used to darken the corners. The red channel is then free and can be used on top of these.

In the green channel, the priority control can be used as a quick and easy method of hardening the edges of the circle. The circle can also be moved around using the trackerball in the MegaDef control panel.

At some point, the ready-made vignette will probably not be suitable as it is not possible to resize the circle or change the aspect ratio. The viewer should now be used to create a new vignette, as follows:

• Press '2', 'expand' and 'show' (or 'mask' if you prefer) in the appropriate channel to select the full screen (as explained in Channel isolation).
• Open the viewer and select 'Single-layer' mode. The top left icon in the MegaShapes toolbar on the left switches between double layer and single layer. This has several effects. In particular, the image is now hidden and drawing is done on a black background, and (more importantly) the size and position of the object or circle in the viewer WILL NOT match the size on the video. However, scaling from the viewer to the pixi is now "1-to-1" and there should never be any strange banding effects.
• Draw a circle in the viewer.
• Press and hold over the 'circle' button in the viewer to bring up a popup window. You should use the width and aspect controls in this window to change the size of the circle to the required size. The hardware resize controls (eg. the outer ring in the DPC panel) should NOT be used, otherwise you may see unwanted banding effects.
• The circle can be positioned as required using the DCP trackerball.
• Once you have a nice vignette in the centre of the screen, to adjust the corners outside of this you can either invert the vignette (using the buttons in the MegaShapes panel) or select a different channel with a lower priority and cover the rest of the screen.