Green Phospor Mac

[fimbulvetr]

So, anyone have an idea on what is going on here:

http://www.ebay.ca/itm/261910330019?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Is this a modification or a weird factory special? I was just wondering the other day if it would be possible to convert one of my compact macs to a green phosphor screen just for fun, when I came across this listing. Perhaps it is a tube out of a IIc monitor?

 

[Compgeke]

If I had to guess I'd say the original CRT broke and they replaced it with a green phosphor they had on hand. The prototype units I've seen all had the B&W CRTs so it'd be odd to have a one-off with a 3.5" floppy and green screen.

 

[TheWhiteFalcon]

Probably a IIc tube. I've seen the amber ones installed as well.

 

[unity]

Whats funny its how the auction it worded. Very carefully without making any actual claims such as "changed at some point" - Ya, last week. Its pretty easy to tell it was just swapped.

 

[Elfen]

Camneerg.com was a website from some engineering student who broke his Classic Mac's screen and used a green phosphur screen as a replacement. But the wiring was not compatible with the tube, so everything was backwards. And this was from the 1990s! Camneerg is Green Mac spelt backwards.

So it is not as rare as one thinks, and it is definitely not some collector's item. It's an attempt to fix something that they broke.

 

[uniserver]

love this wordage,   

RARE - MACINTOSH 512k COMPUTER with GREEN SCREEN (phosphor) CRT, DEVELOPER UNIT?

Here is your chance to own a wonderful example of an early Macintosh computer from 1984.
Model #: M0001W. This computer has been modified at some point to a green phosphor CRT.
An amber or a phosphorus green screen CRT was claimed to give improved ergonomics,
specifically by reducing eye strain. This would, in theory, provide an advantage to programmers
who would often spend long ours in front of a computer screen writing code.
 
This computer is guaranteed to have a authentic working green phosphor CRT.
No circuitry has been modified to make this work and not filters have been applied to the screen.
This machine is definitely an item of curiosity, but cannot be authenticated as a prototype unit.

Also Known as | BULLSHIT | --------

 

[TheWhiteFalcon]

First time I've heard ergonomics applied to screen color.

 

[techknight]

Careful. your treading on the territory of one of the rules here.

But I digress.

I do sorta like the green CRT.

my IBM 5155 has its stock amber CRT, and I really cant stand amber that much. id rather have green or black and white

 

[360alaska]

I have an SE/30 with a green phosphor screen, nothing super special about it, i would like to get my hands on an amber screen for my other we/30...

 

[uniserver]

yeah heck for a grand , buy 2 of these developer units?

lol

 

[Gorgonops]

First time I've heard ergonomics applied to screen color.

I guess you're young, because the whole selling point of those colored phosphors was ergonomics. However I will grant it's not the *color* per se that was the selling point; the green and amber phosphors used in those tubes "decays" more slowly than the standard P4 white phosphor used in TV-grade monochrome tubes, IE, it emits the energy absorbed from the electron beam more slowly. With a standard white tube a given pixel is very bright at the moment the beam is hitting it but fades almost to black before the beam hits it again, so the display essentially strobes at 50-60hz. The green phosphor, on the other hand, glows less brightly while absorbing the beam but takes a decent fraction of a second to release the energy so the display has a steadier glow, which, as noted, was claimed to reduce eyestrain.

(Personally I can vouch for it, mostly when talking about 12" or larger monitors running a the 50hz MDA/"Hercules" refresh rate; white MDA monitors will burn your eyes right out of your skull. With 9" monitors the flicker from P4 phosphor is less noticeable because the human eye is more sensitive to flicker in the edges of the visual field rather than the center.)

The downside of P1 green phosphor is it actually takes so long to decay that moving objects on the screen leave "ghosts" behind them, which is a bigger problem with graphics/GUI vs. text displays, and the phosphor is also more prone to burn-in.

 

[TheWhiteFalcon]

And I suppose eyes are a method of interaction with the computer; just that today when "ergonomics" is brought up, I tend to think of furniture, keyboard/mouse, shaping, etc.

 

[techknight]

makes two of us. 

 

[Gorgonops]

And I suppose eyes are a method of interaction with the computer; just that today when "ergonomics" is brought up, I tend to think of furniture, keyboard/mouse, shaping, etc.

There were even companies that made a living selling kits to retrofit these tubes into computers that came with the "bad for your eyes" white phosphor tubes. Somewhat ironically, given the increasing focus on ergonomic issues in the latter half of the 1980's, monochrome monitors ended up moving almost entirely back to the white phosphor in large part because of how the Macintosh pushed the "screen as a literal representation of a piece of paper" metaphor into people's heads; paper is white so the screen should be white, right!

Anyway, after the death of mono monitors the word "ergonomic" was used throughout the 1990s to describe color monitors that supported higher-than-60hz refresh rates designed to reduce detectable flicker so, yeah, the word totally applies to "measures to reduce eyestrain".

(You won't see it very often *directly* applied in, say, archived sales material for green monitors, but that's mostly because the word "ergonomics" wasn't really in vogue until the mid-80s. But there are examples to be found.)

 

[techknight]

 monochrome monitors ended up moving almost entirely back to the white phosphor in large part because of how the Macintosh pushed the "screen as a literal representation of a piece of paper" metaphor into people's heads; paper is white so the screen should be white, right!

Its funny how when things change, they stay the same. Even today, google is doing/has done the very exact thing with the stupid material UI and android. 

 

[Garrett]

Love how they think it's a developer/prototype unit, then state this (which proves it isn't a prototype):

According to the Serial No. of this computer, it was made on the 39th week of 1984.

Plus, it's a 512k - not as special as the 128k, which isn't even that special unless it is the Twiggy Mac or an early production unit, or a prototype.

 

[CelGen]

Love how they think it's a developer/prototype unit

How many times have we here on the forums called something a prototype because it did something we normally did not expect/had an Apple asset tag?

 

[unity]

^ very, very few times. I think most folk here are good at debunking such things.

 

[Garrett]

Yes, unity. But then again, most people on eBay and Craigslist who don't know a whole lot about Macintoshes are very quick to call something a prototype/developer unit.