That is so cool to watch! A real cut and paste! I've spliced 8mm film before but have never seen anything so sophisticated. Was that film or tape? I presume that was "real" equipment and not just a "set"? In any case, thanks for sharing.
wrote on 7/16/2015, 10:20 PM
That was 2" videotape. Looked pretty real although from what I understand, it was a lot more tedious to do.
Video tape (even 2" wide) is recorded at a skewed angle. You cannot make a perpendicular cut without creating very noticeable nasty artifacts in the final joined tape. Editing was performed electronically with two tape units: the source and destination. What you see in the Mission Impossible episode is probably a film splicer.
wrote on 7/16/2015, 10:51 PM
Tech Diver, that is a videotape splicer. 2" Quad video is almost perpendicular. I know several editors that edited tape this way. the show "Laugh-In" was edited by cutting the physical 2" tape.
and you sometimes had only one shot to get it right.
There was powder that was spread on the tape so you could see the control track and your splice was created along these control tracks. It was quite an art.
Helical Scan vtr's have a long diagonal scan so you cannot edit it physically.
Explanation of the process
I thought it was cool that they did it on a MI show in the 70's.
I do remember seeing that episode when i was a small tot. It was one of those defining moments that helped spur my undying lifelong interest in all things tape and recorded and audio/video. But, even when i saw it, i already knew about helical scanning heads and wondered how they'd get a clean splice. I guess i didn't know that deck used perpendicular scanning instead.
wrote on 7/17/2015, 9:34 AM
There may be an error in the show itself, because that particular tape deck they are using appears to be a helical scanning deck. There are not many portable Quad machines, so they may have taken poetic license on that.
But in the video, you can see that the tape is wrapped around the scanner, whereas quad machines were laid out more like multitrack audio recorders, with the scanner spinning perpendicular to the tape.
Of course, they took a lot of poetic license in this show in general.
I have no idea what type of deck is shown in the clip, but the first production company I worked for in the early 80's had an Ampex "portable" quad machine. I enquoted that because it was like a uranium brick in a lead suitcase. Almost killed myself loading into the van the first time.
Thank you for correcting my misconception about skewed recording vs. perpendicular for 2" tape. Back in the early '70s I used a pair of Sony BVU-100s with an edit console when I worked in Sony Broadcast division. Those units used 3/4" tape cassettes with skewed recording. Each BVU-100 cost about $20k (in 1970), which is equivalent to at least five times that amount today. The 2" reel-to-reel units were a whole lot more expensive than that.
The first VTR i ever played with was an old Ampex 1" machine. It took 14" reels, though we only had 10.5" on hand. It used helical scanning with a head drum that was about 7" in diameter. The takeup real was about 1.5" or 2" higher away from the frame than the supply reel, which was how they accomplished the helical wrap around the drum without putting any sharp bends in the tape.
It was about the size of a desk. I don't really have any idea how much it weighed, as i was never involved in moving it, which took 3 or 4 adults to push the cart around. After all, i was only about 4 years old when they let me use it. Must have been back in '67 or '68.
Not too long after that the school got a Sony 3/4" cassette U-Matic deck that was about 1/4 the size, and could record color!
I never willingly worked on video tape equipment but in the very early '80s, I worked on the IBM 3851 Mass Storage System that stored data in 4K stripes diagonally on tape. The tape would wrap diagonally around a cylinder that contained the spinning read-write head. Even though the data was stored on tape, it was "staged" on M/T3350 disks called staging adapters and the systems saw it as a disk. That was when disks were expensive and tapes were relatively less expensive.
These days, there are [I]Virtual Tape Systems[/I] in data centers that are made up of all disks emulating tapes.
wrote on 7/17/2015, 2:44 PM
The first VTR I used were Sony portable 1/2" reel to reel videotape. In College, I think we had one that did color, and the other's were black and white. Edited by hitting the record in button while tapes were rolling. Then in TV station I used Ampex Quad VTR's that were side by side. This allowed you to do a tape delay by recording on one and playing back on another.
I also used Sony 1/2" reel to reel in college (UCLA). Strictly B&W as I recall. They were helical scan so no editing the physical tape. We had 2" RCA equipment for broadcast. So editing on the 1/2 tape was accomplished by doing a studio "optical" transfer.. We used studio TV cameras to shoot a critically aligned studio monitor. We'd be playing back the 1/2" on the studio monitor and recording the output of the studio switcher to 2" tape. We'd pause the 2" tape at the edit point -- then cue up the next shot on the 1/2" -- then roll the 2" tape when we hit the edit point on the 1/2". It was "add-on" editing only. No dissolves or effects between scenes but we could do titles over. Laborious to be sure. But it did allow us to do high shooting ratios on documentary projects with little cost. I did an hour documentary show that aired on KCET in LA.
I still have a couple rolls of 1/2 tape with no idea what is on them.
I remember the IBM "Data Cell". I was working at the University of Michigan computer center while going through engineering school. The associate director of the computer center was all excited to get an early machine to attach to out dual IBM 360/67 computer. A bunch of grad students had written an operating system called MTS (Michigan Terminal System) for the 67s. In Math 573 we had to create portions of the OS and prove they worked. There wasn't a computer science department back then (late 60s), there was an ad hoc group made up of math and electrical engineering profs. Although the director of the center was a philosophy prof as I recall. I also remember a high tech buzz when the 026 keypunches were replaced with 056 keypunches.
The first video tape machine I had contact with was an Ampex VR-1000A, a quadruplex machine. It was out long before any form of helical scan machine.
You could perform manual splicing, but it was not done like shown in that clip. There are a number of things about that clip that are just plain wrong. Electronic editing came out a very short time later, so manual splicing was abandoned.
You could not manually splice tape from a helical scan machine due to the shallow oblique angle of the tracks, and the machine in that clip is definitely a helical scan machine. I don't recognise the type, but it reminds me of an IVC machine.
Manual splicing required you to paint the tape using 'developing liquid', a fine suspension of iron powder in a liquid base. You then aligned the tape and made the cut between the tracks at the correct spacing to preserve the control track. The tape was joined with a cement, the backing tape only being used to keep it in place while the cement dried.
Once dried, you held your breath every time the splice passed the heads, as it was not uncommon for the rotating heads to tear the splice apart.
What is interesting about that clip is the 2" helical scan VTR, most helical scan machines used 1: or narrower tape. Ampex made a VR550 and a PAL version the VR650 which were the earliest helical scan machines, and IVC made some early 2" helical scan machines.
The portable Ampex machine that atom12 refers to was the VR3000. It was originally developed as an instrumentation recorder for the early space program, making flights in Redstone rockets. It was adapted by Ampex for use as a portable quad scan machine and the main reason for its heavy weight were the batteries. They used Gates lead-acid cells which weighed a ton. The VR300 was a mongrel to use on location, as they had a nasty habit of not recording in colour at times, and as they had a limited playback mode, you only found out when you got back to base.
An interesting thread. The one thing it proves is that we're a bunch of old far_s, a bit nostalgic for times long past. I never had any experience with video like you, but did learn Fortran back in the 60's using an IBM 7040. Found this pic.
For me, the most impressive thing was watching those tape drives, moving back and forth, repositioning. At the time, it seemed a bit magical. In a way, it still does, unlike the mundane little boxes we use now that sit under our desk out of sight, but I wouldn't trade.