FDI(OPCS), FDO(OPCS) Optical Printer Control System FDI(OPCS), FDO(OPCS) NAME fdi/fdo - set up an automatic fade in/out USAGE fdi [-x] frames fdo [-x] frames The -x option overrides the error message that warns you about doing a fade when the shutter isn't fully open/closed. This allows you to do fades from any fader position. EXAMPLES fdi 24 # Set up a 24 frame fade in fdi -x 24 # 24x fade, regardless of current fader position DESCRIPTION Set up a fade. Whenever the camera is told to expose a frame (with CAM(OPCS), REP(OPCS), etc), the fader will automatically move to the proper positions before exposing each frame. Fades are based on a logarithmic curve that can be customized with FLOG(OPCSDEFS). Fades can occur on either still or moving images, depending on the command used for exposing film; 1) fdi 12 cam 12 # fade in 2) rat 1 2 fdo 12 rep 6 # fade out with step print #1 sets up and shoots a 12 frame fade-in on a still projector image. #2 sets up and shoots a 12 frame fade-out on a moving projector image on twos. Fades will remain in effect until all frames of the fade have been shot. The following are equivalent, and all shoot fades similarly: > fdi 12 cam 12 > fdi 12 cam 6 cam 6 > fdi 12 cam 6 pro 1 pro -1 cam 6 NOTES > fdi 0, fdo 0 or a SHU(OPCS) command with any value will cancel any pending fade or dissolve. > A status message near the fader's counter shows how many frames are left to go for the fade. > Normally, the fader must be: o OPEN before executing FDO o CLOSED before executing FDI If not, an error message will be generated warning you of the situation. The only exception is if -x is supplied, preventing error messages, shooting the fade based on the fader's *current* position. Below are some common errors: fdi 12 cam 11 fdo 12 cam 12 ^bombs here: only 11x into a 12x FDI. opn fdi 12 cam 12 ^bombs here: fader is already open It's hard to see such errors in large '.run' scripts, so it's advised to test scripts with 'motors off' to find such problems quickly, without wasting film or waiting for motor positioning. SEE ALSO OPCS Commands CAM(OPCS) - shoot camera (fades/dissolves too) OPN(OPCS), CLS(OPCS) - open/close fader shutter SHU(OPCS) - move fader to an absolute position in degrees DXI(OPCS), DXO(OPCS) - set up dissolve in/out FDI(OPCS), FDO(OPCS) - set up fade in/out OPCSDEFS Commands FLOG(OPCSDEFS) - set Fader LOGarithmic curve for custom fades FRANGE(OPCSDEFS) - set fade/dx's degrees range (for Hicon film stocks) INTERP(OPCSDEFS) - set interpolation positions (fader, focus, etc) SLOP(OPCSDEFS) - correct for slop in a motor (fader, focus, etc) General MATH(DOCS) - math expressions (for use in frame specifications) SYNTAX(DOCS) - online calculator and OPCS math expression syntax ORIGIN Gregory Ercolano, Los Feliz California 11/29/89