The ELMO TRV-35 slides into your video feed

That name is a double pun; congratulations if you caught it.

Chapters:
00:00 Intro
01:35 Overview
08:06 Demo
14:30 Inputs & Outputs
16:50 Camera controls
23:20 Remaining features
25:03 Other Transvideo models
28:45 Disassembly
31:15 Internals
34:13 RS232 remote controls
36:52 Camera mechanism / repair
40:48 Slide mechanism
44:12 Conclusion / Outro

[CathodeRayDude]

Yes, I know the spring is under compression, not tension. I have no idea why I said tension.

[Klatchan]

Worked at a school: the ELMO projectors were always outdated because goddamn those things DO NOT DIE.

[nhkr]

Working in a contemporary art museum, we deal with slide projectors all the time. It's actually the perfect profession for someone interested in technology from all eras (which means, by extension, loving this channel). One of the most impressive things I've ever seen is a Nan Goldin exhibition, where there were at least 12 slide projectors connected to a computer to control them all. Six projectors at a time would project their own section of a photo, three wide and two tall, and when the carousel reached the end it would switch to the other six. The amount of alignment and ND filters to make them all run must have been immense, as well as the upkeep of repairing that many machines in 2023. Also, when the show ended and all the machines reset back to the starting position, the rattling of all 12 going back to zero was pretty amazing.

I've only had to control a single projector show like this, but the software and accompanying hardware only works on era macs, so it was a bit of a challenge.

[porklaser]

The moment you turned it around to reveal a row of BNC connectors I went from "Meh" to opening an ebay tab in less than a second.

[edgeman]

I swear, you and Alec from Technology Connections can make videos about something I care NOTHING about and not only make me watch the entire thing but also be entertained the entire time.

[HeadsetGuy]

Elmo apparently was such a big name in the school document camera business (and perhaps still are) that teachers at the schools I work for still refer to their non-Elmo document cameras as "Elmos".

[shmehfleh]

Because I'm an old, I did some school presentations on slides. The fanciest one I did involved a tape recording of the presentation's audio and two slide projectors aimed at the same screen and wired to a special control unit. One slide projector held the odd slides while the other held the even slides. When it was time to change slides, the audio recording had special, sub-audible markers inserted that the control unit could detect. It would use those cues to turn off one one projector's bulb while simultaneously turning the other's on. The dark projector would then advance to the next slide in the carousel. The effect was a very smooth and very professional-looking cross-fade between the two slides, using just the thermal inertia of the projectors' bulbs.

[famitory]

the capability to zoom into the slide and genlock+serial control the thing makes me imagine a fly-by-night broadcast studio using this and a frame buffer as their static matte source, clunking through backgrounds and fake-CG elements to shove underneath and above talent with a stack of keyers. every night they have a 125 year old savant paint the weather onto a copy of the local map directly onto the tiny slides.

[tehlaser]

Did— did I just watch a 45+ minute video about a slide projector? I have no idea how you make these videos so interesting Dude, but damn it, you do.

[jeevesmcqueeves]

i have heard a story of someone using 6 to 8 genlocked (slightly offset from one another) projectors *without a video mixer*, just all pointed at the same point on the wall, to do some kind of faux-crossfade. i imagine hearing all those clunks going left-to-right behind you at exactly the same rate every time was a very satisfying experience

[benmolay]

9:55 I'm sure plenty of people did it on accident, but I know of at least one instance of it being done on purpose. In the early touring days of Pink Floyd they would take two slides, add a drop of oil between them and put them into the same slot and leave it projecting as they played. As the oil heated up from the projector lamp it would move around and create a "psychedelic" effect.

[wilsonkilmer]

It’s me! I am into slide projectors! I still get slides made, it’s a whole event to look at them with friends. Love this

[oldtvnut]

Sylvania in 1969 sold a console color TV with a built in flying spot scanner and Carousel changer for home use. It did not have any zoom control, and just displayed the 4x3 center portion of the slide. Also, no video output. It did have one advantage in that the low light level from the flying spot tube would not fade the slides.
For comparison, automatic repeating projected displays for corporate PR would typically fade slides noticeably within a week.

[Pantology_Enthusiast]

"Wait, wait, I know it's a slide projector but don't leave!"
_Skelator pointing "Jokes on you, I'm into that shit!"_

[CantankerousDave]

16:35 - I volunteered at the local community cable station in the late 80s. One show I worked on was a movie review show, and this was back when studios sent out "EPK" (electronic press kit) packages containing a tape with clips and some 8x10 b&w stills from the movie. To get those stills into the show, you would mount them on a rostrum frame with a dedicated studio camera pointed at the photo, lit in such a way to prevent glare. No digital frame store, you just cut to the still camera feed and swapped in the next photo as you went. That's pretty much what this is doing in a single box, but just with slides. I remember framing up the shot on the stills and then locking down the camera; no fancy camera moves for us.

[CoreyThompson]

Many TV stations used slides for things like Station IDs, trouble, promos, and such into the 1990s. Could definitely see one of these in a small market TV station or community access TV

[TigerAceSullivan]

9:32 you just unlocked so many memories i have of students trying to use a document projector and spending a solid 20 seconds fumbling with the paper trying to get it in the right orientation

[ronbokje]

When I was working at the head office of Bang & Olufsen in the Netherlands they had 21 kodak carousel projectors connected to a reel to reel tape recorder that send out pulses to operate the slide projectors and played the sound for the slide show. there where also machines with cassette tape that could operate the projectors. it was really nice to see a presentation on it with slides overlaying and so on. around 2000 they throw them away. so I started to collect them and had more than 100 different slide projectors, only hold on to the kodak carousels, after a lot of trying I convert them to LED, less heat and some I took out the fan so no noise and you can project 1 slide forever without overheating them. also once I put a lcd screen from a old Casio digital camera, it had a video in on the print, and without the backlight you could project in really big pixels whatever you liked. was nice on parties where from a distance you see an image and close it looks like color chancing tiles. Have a big tele and very wide angle lens for them. this Elmo thing is something very nice.

[oldtvnut]

In the mid 60s, the PR department of the college I attended had three projectors in separate side-by-side futuristic rear projector enclosures (20 inch screens), with all three advancing simultaneously with a single control pulse. I installed a punch paper tape reader so that it advanced on each pulse but the individual projectors either did or didn't depending on the corresponding holes in the paper tape. This saved them from making duplicate slides for the times when they wanted the image to stay the same on one of the screens.

[colindragan]

46 minutes of CRD reviewing a strange, obscure device that I have no use for? LETS GOOOO