phys009@csc.canterbury.ac.nz (03/04/91)
Hi Folks
I am about to buy a DecStation 5000 to do visualization with, and am wondering
about presentation animation...
Has anyone out there tried to attach a frame grabber in order to produce movies
from one of these. Is anyone in a position to tell me what hardware I might
need, and how to go about it?
Help ...
Bryan Lawrence
Voice: (44)(865)272930
Janet: uk.ac.ox.atm.isams::lawrence
Internet: lawrence@isams.dnet.nasa.gov
Mail: Dept. Atmos. Physics., Clarendon Lab., Parks Rd, Oxford OX1 3PU. U.K.yeidel@wsuvm1.csc.wsu.edu (Joshua Yeidel) (03/05/91)
In article <1991Mar5.005311.176@csc.canterbury.ac.nz> phys009@csc.canterbury.ac.nz writes: >Hi Folks > >I am about to buy a DecStation 5000 to do visualization with, and am wondering >about presentation animation... > >Has anyone out there tried to attach a frame grabber in order to produce movies >from one of these. Is anyone in a position to tell me what hardware I might >need, and how to go about it? > >Help ... > >Bryan Lawrence > >Voice: (44)(865)272930 >Janet: uk.ac.ox.atm.isams::lawrence >Internet: lawrence@isams.dnet.nasa.gov >Mail: Dept. Atmos. Physics., Clarendon Lab., Parks Rd, Oxford OX1 3PU. U.K. > I presume from your mention of a frame-grabber that you are thinking in terms of video when you say "movies". You may want to think about film as well. We are in the process of setting up to do scientific visualization (including animation) on a DECstation 5000 PXG Turbo (3-D accelerated system). We are intending to use S_VHS as our capture and distribution medium. We will use a Chromatek Scan Converter to take the system's RGB video output (with loop-through back to the system monitor) and down-convert it to S-Video. This is a very expensive device (about $23,000), but it offers a capability to specify exactly what rectangle on the computer screen is converted to the full video screen (plus indcependent horizontal and vertical scaling to adjust aspect ratio). The net result is that images of any size can be captured WITHOUT messing with the generating software. The Lyon-Lamb RTC converter is the only competitor I know of with a similar capability, but it is slightly more expensive, uses 10 amps instead of 2 amps, has six fans (noisy) instead of one, and is three times the size. (On the other hand, L-L is THE top name in the field and is USA-made, whereas the Chromatek is made in Japan.) We are hoping at this point to do without stop-frame animation (that is, we will use a free-running VTR to capture images as they appear on the computer, rather than trying to drop one frame at a time onto the VTR). The latter approach requires an animation controller, and I hear it grinds up VTR transports due to the rewind-preroll sequence required for each frame. I'm hoping that we will be able to rack up frames on disk in some convenient format and then play them back at appropriate speeds. We are also working to get money for an S-VHS editing bench (two decks, controller, and audio gear) so we can make something that resembles professional output (i.e., not immediately obvious that they're "home movies"). We would like some sort of switcher/effects device to go with that, but it surely won't come out of this budget year. I caution you that everything I say is WITHOUT benefit of experience -- we're expecting the Chromatek in about two weeks, and the VTR's are not even ordered yet. Draw your own conclusions. -- Joshua Yeidel
kludge@grissom.larc.nasa.gov ( Scott Dorsey) (03/05/91)
In article <1991Mar04.193544.25474@eecs.wsu.edu> yeidel@wsuvm1.csc.wsu.edu (Joshua Yeidel) writes: >phys009@csc.canterbury.ac.nz writes: >>Has anyone out there tried to attach a frame grabber in order to produce >movies >>from one of these. Is anyone in a position to tell me what hardware I might >>need, and how to go about it? >I presume from your mention of a frame-grabber that you are thinking in terms >of video when you say "movies". You may want to think about film as well. I am currently doing animation with pv-wave, using a Bolex H-16 camera. I've put a Kern-Switar flatfield lens on the beast, pointed it at the CRT, turned out the lights. I've got a shutter release cable taped to a solenoid from an old washing machine, which is controlled from the serial port of the '5000. Whenever any character is sent out the port, the shutter fires. Because the Bolex has an adjustable shutter angle, there is less of a problem with flicker, although I suspect that with the camera in single-frame mode at 16 fps, the standard shutter angle would do. (This would be an effective exposure of about 1/35 sec, right?). In any case, the camera resolution is a lot higher than that of the DS5000/200PX that we are using for display, even using the crappy 7239 film that the stockroom here carries. I heartily recommend film for animation. --scott
gemini@salyko.doit.sub.org (Thomas Holst) (03/12/91)
you should better buy a machine where software is available for, i.e. silicon graphics. anyway, have fun.......