Browsing through here, and taking a look at pictures of roundie sets that their owners are obviously quite proud of, I have thought up some questions, and I have a few other thoughts.

Why were roundies made, when as far as I know, the NTSC picture has always been rectangular? I've seen some old 40's sets with rectangle screens, so why were "fishbowl shaped" screens made to begin with?

Also, do roundies draw the corners of an image? or does something cut them off and convert the image into a "fishbowl" shape?


This may be biased, seeing as I grew up with rectangle screens, but with a roundie, you can't see the corners of an image (Channel logos, etc), so while they may have great color reproduction, I would think a rectangle screen would be more desireable since it shows all of the picture (Well, most of it, depending on overscan)

The round screen has nothing to do with NTSC or any particular styling. They just didn't have the technology to make a rectangular color picture tube correctly and cheaply enough.

I could care less about corner logos and text on the overscan. As far as I'm concerned TV was designed for moving pictures, not for reading news headlines or looking to see what channel you're on.

The point is the original color NTSC sets produce a way better picture than anything else today. More care was put into making the set during the 60s and early 60s than with their later rectangular counter parts. Just compare the reds on a 15gp22, 21cyp22, or even an 21axp22 with a later rectangular tube. The reds are much deeper and look alot more natural.

The only thing that comes close in reproduction to the roundies is the chromacolor seties, and its still not anything that close.

SO the factors that make me want to collect them:

1. extremely well made
2. brilliant color reproduction
3. --and they just look cool :D

my .02

The round screen has nothing to do with NTSC or any particular styling. They just didn't have the technology to make a rectangular color picture tube correctly and cheaply enough.



That's what I thought too, but like I said, I saw sets from the 40's with rectangle screens. They were black and white of course, but the screens were rectangle.

The tubes of 40s black and white sets were round, but different manufacturers had different styles of masking them. Some masked just the top and bottom, so they looked like roundie color sets. Others masked the top, bottom, and sides, so the picture looked more or less rectangular. A few didn't mask at all - the "porthole" style.

As Steve points out, all the '40s tubes were in fact round, but many were masked off to be rectangular since movies and shows would work better on a rectangular screen. Then in a war among manufacturers to advertise bigger viewing areas, they did away with the rectangular mask in '49-'50 to make the viewing screen show more of the face of the tube. That way, they were able to advertise a bigger viewable area without using a much more expensive larger tube. Simple ad gimmick.

As far as color tubes, Jordan gave a good answer. Why we like them? Because the have disappeared from society. Being 40 years old, my childhood memories include just about every family having a round tube 1960s color TV in the livingroom. With Halloween coming, I remember when I was trick-or-treating in West Los Angeles in the mid 1970s, how every house I'd go to would have a roundie blaring away in the corner of the livingroom. We didn't have one; we had a 21" GE B&W console at that time. So I was always jealous of our color TV neighbors. So between nostalgia and the fact that roundies aren't easy to get anymore, they are desirable collector pieces.

Charles

As Steve points out, all the '40s tubes were in fact round, but many were masked off to be rectangular since movies and shows would work better on a rectangular screen. Then in a war among manufacturers to advertise bigger viewing areas, they did away with the rectangular mask in '49-'50 to make the viewing screen show more of the face of the tube. That way, they were able to advertise a bigger viewable area without using a much more expensive larger tube. Simple ad gimmick.


Now that makes a lot of sense, and I can see how this would happen.


Here's another question: The corners are cut off on a roundie, but I'm pretty sure the corners are still drawn. Are the corners projected onto the sides of the tube? Are the beams absorbed by the sides of the tube?

Better yet: With the corners cut off on most sets, could broadcasters have put "easter eggs" into the unseen corners? This was before rectangle tubes and VCR's, so I wonder if some broadcasters put something in the unseen corners as a joke or something.

The corners are cut off by the shape of the screen, but they're still there on the edges of the glass. If you see a B&W round tube with a little bit of phosphor residue on the sides of the glass, you can actually see the corners of the picture. On a color roundie, you wouldn't be able to see the corners due to the shadow mask and other internals.

I believe that broadcasters would avoid putting anything important in the corners. Steve D might be able to elaborate on this, but I don't think they tried putting anything like icons in the corners 'til the 90s.

Charles

It is my understanding that both the first b&w CRTs and the first color CRTs were round due to pincushion issues. That is, the rectangular picture would have a pincushion(the tops and sides would bow inward)effect unless correction was added. For b&w sets, a permanent magnet scheme was developed. As this would not work for the 3 beam color tubes, it took some time to develop the circuitry. Developing the square CRTs is another issue.

For a round tube b&w set, any late 1940s TV is a good example-almost all have round tubes.

When I worked in radio/TV operating cameras I remember broadcast cameras at least used to have an area marked off inside the viewfinder that you were supposed to keep the most important parts of the picture in (like people's heads) and I think this represented the area of the round color picture tube.

The effect on a round set would be the same as if you increased both the width and height controls on a rectangular...the edges are just outside of the area of the tube. It would be possible to see the whole picture on a round color tube if you "underscanned" both the height and width.

I know rectangular studio monitors of the late 90's allowed you to underscan the picture to make sure you saw all of the edges of the picture...did the round color studio monitors also have such a feature, or were they adjusted by default to underscan the picture?

Another thing to remember is that tube sets were designed with significant overscan in both the horizontal and vertical directions. This was so that as tubes aged, the rasters would fill the screen for a longer time before the deflection tubes had to be replaced. As a result, broadcasters avoided putting inportant stuff not only the corners, but the top, bottom, and sides of the screen.

Yeah I know there is/was a "safe area" marked out on viewfinders due to the various degrees of overscan that TV's had/have.

What I'm wondering now is if somebody was clever enough to hide some kind of joke in the unseen corners/edges, like maybe a small line of text, or a funny image.

Hi,

I assume that the roundscreen look is more natural than the rectangular view. The view of our eye is round. It is not rectangular. We have no rectangular eyes. And so I believe that the recent fascination of roundies might depend on unconscious sympathies for the more natural view.

The rectangular view depends only on our line-scanning procedure. But a rectangular screen somehow looks artificial.

Kind regards,
Eckhard

Roundie color sets were expensive items in their day, & as such were targetted to a wealthier, more "sophisticated" audience. They usually were designed to have great eye appeal, had a conservative look about them that would "wear" well for many years in a home. The round screens are kinda odd looking today, but today, in a sea of ugly black plastic cubes, they are refreshingly different.

When I worked in radio/TV operating cameras I remember broadcast cameras at least used to have an area marked off inside the viewfinder that you were supposed to keep the most important parts of the picture in (like people's heads) and I think this represented the area of the round color picture tube.


...don't mean to hijack the thread, but this brings up a pet pieve of mine. The station were I work has robotic cameras in the studio now, as do a lot of modern TV studios, and we have Marshal 5" flat panel LCD monitors in production control... Well, some of the technical directors don't realize that the LCD panels display the entire video frame, and they adjust the shots based on what they're seeing in those displays. So... when I'm at home watching the newscast on a CRT TV, the framing looks odd.

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I will be 60 on Nov 5th, and I alos can remember seeing color when my dad took me to a tv store somewhere in South Bend. That image was embedded in my memory and even though I was only about 8 or 9 I was hell bent to have a color set in our house. I guess the round tube sets help revive that magical time when color seemed about as probable as Flash Gordon landing with Dr. Zarkov.

I was surprised to find other people just like me that had the same experience.

Although color tv was not completely unknown to me, I had never seen a roundie until 1974. It was in my grandparents house. It was a 1965 Zenith console, the same model that I have although not the same set. I was fascinated by the screen shape as all I knew were rectangular sets. I never forgot it and have wanted one since that time. I only have one such set, but one is enough for me as they require a lot of space and are expensive to restore.

As was mentioned earlier, the extra difficulties with convergence and pincushion presented by a rectangular tube were the reasons the first color sets were round, not an inability to blow a rectangular glass funnel. As for hiding 'easter eggs', I am sure they didnt. . remember, there were millions of B&W rectangular sets watching. I dont know when the technology for adding that garbage came along, but I dont recall seeing it until the eighties.

FWIW, I have opinions and information on several things in this thread:

The scanning of the corners of the image onto the bell of the round color tubes was detrimental in another way besides content loss - the 21kv electrons would generate about 16 kv or so secondary electrons, which would scatter all over the tube face and light up all the phosphors a bit, reducing the contrast and color purity whenever there was somethng bright in the corner of the image. With the inefficient early red phosphor, which required more beam current, this meant that the green and blue lit up more with this stray light, so a pure red was harder to obtain in practice. Even though the red phosphor itself may have been a bit more saturated, depending on picture content, the blue and green were lit up somewhat when they shouldn't have been. Later picture tubes did much better at maintaining color purity and contrast into the lowlights when the picture also contained bright areas, and this was just one reason why.
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As to seeing things in the corners and edges - just play an old color show, like the last Howdy Doody show, onto a 16x9 HD set (so the left and right edges are completely visible), and you'll see plenty - plenty of misregistration, target flicker, horizontal sweep ringing, and other TK-41 camera shortcomings.
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Biggest problem with cutoff material on roundies in the old days was movie titles. these days, calbe box menus, DVD menus, etc. all extend into the roundie cutoff corners.

On the other hand, sets were too wildly variable in centering and scan size for anyone to put an Easter egg in the corner and be sure it wouldn't be seen.
The edge cut off might be anywhere from zero to 10% of the picture. Solid-state sets got more stable, but not always any better in manufacturing tolerance. A decent solid state CRT set with adjustments (like CRT projos) should not overscan more than, say, 3%, in my opinion.

As time goes by, it will be less likely that flat panel sets will need overscan; but at this point there is still a need for some, since the source material in some cases has suffered a bit of loss while in the analog domain. People are gettting used to 25% black bars when the aspect ratio mismatches the screen, but just a little black that comes and goes with source material looks like an annoying malfunction.
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Regarding old professional monitor underscan, professional color monitors always had an underscan switch. This was essential in seeing the whole image while setting up a camera for registration and proper scan on a (printed) test pattern. These monitors also had a "pulse-cross" switch that would offset and enlarge the vertical scan so you could see the vertical sync pulses and determine quickly if they were normal.

FWIW, I have opinions and information on several things in this thread:

The scanning of the corners of the image onto the bell of the round color tubes was detrimental in another way besides content loss - the 21kv electrons would generate about 16 kv or so secondary electrons, which would scatter all over the tube face and light up all the phosphors a bit, reducing the contrast and color purity whenever there was somethng bright in the corner of the image. With the inefficient early red phosphor, which required more beam current, this meant that the green and blue lit up more with this stray light, so a pure red was harder to obtain in practice. Even though the red phosphor itself may have been a bit more saturated, depending on picture content, the blue and green were lit up somewhat when they shouldn't have been. Later picture tubes did much better at maintaining color purity and contrast into the lowlights when the picture also contained bright areas, and this was just one reason why.
-------
As to seeing things in the corners and edges - just play an old color show, like the last Howdy Doody show, onto a 16x9 HD set (so the left and right edges are completely visible), and you'll see plenty - plenty of misregistration, target flicker, horizontal sweep ringing, and other TK-41 camera shortcomings.
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Biggest problem with cutoff material on roundies in the old days was movie titles. these days, calbe box menus, DVD menus, etc. all extend into the roundie cutoff corners.

On the other hand, sets were too wildly variable in centering and scan size for anyone to put an Easter egg in the corner and be sure it wouldn't be seen.
The edge cut off might be anywhere from zero to 10% of the picture. Solid-state sets got more stable, but not always any better in manufacturing tolerance. A decent solid state CRT set with adjustments (like CRT projos) should not overscan more than, say, 3%, in my opinion.

As time goes by, it will be less likely that flat panel sets will need overscan; but at this point there is still a need for some, since the source material in some cases has suffered a bit of loss while in the analog domain. People are gettting used to 25% black bars when the aspect ratio mismatches the screen, but just a little black that comes and goes with source material looks like an annoying malfunction.
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Regarding old professional monitor underscan, professional color monitors always had an underscan switch. This was essential in seeing the whole image while setting up a camera for registration and proper scan on a (printed) test pattern. These monitors also had a "pulse-cross" switch that would offset and enlarge the vertical scan so you could see the vertical sync pulses and determine quickly if they were normal.

The "natural" view area of two eyes is closer to the 16:9 aspect ratio of HDTV and HD DVDs than to the shape of a round CRT.

The "natural" view area of two eyes is closer to the 16:9 aspect ratio of HDTV and HD DVDs than to the shape of a round CRT.

Yep. The Japanese did studies on the best frame shape for HDTV, and came up with 15x9 IIRC, later modified to 16x9 for mathematical elegance and because that was the middle of the various movie formats.

Most paintings are slightly rectangular, like maybe 1.2:1 or 1:1.2. A tall oval frame makes an elegant portrait. I wonder if round/oval paintings would be more common if round canvases and frames were easier/cheaper to make?

now that i have a picture on my roundie- i forgot what red ,blue,and green really look like! the color reproduction is movie quality.technicolor at home!i dont care about the shape,overscan ,easter eggs,etc-the picture is as i remembered back in the early 60s in downtown columbus,shopping with my dad for our first color set.the excitement and fascination of all the different models.with a cable box, the picture is flawless.i have a dlp 106 inch projector with hd hook-up in my movie room and i like my rca much better.can t wait to get started on my zenith roundie!

By the way, this reminds me that Kenny Rogers once said he took pictures at the zoo - and the giraffes ordered a dozen 80x10's.

The corners are cut off by the shape of the screen, but they're still there on the edges of the glass. If you see a B&W round tube with a little bit of phosphor residue on the sides of the glass, you can actually see the corners of the picture. On a color roundie, you wouldn't be able to see the corners due to the shadow mask and other internals.

I believe that broadcasters would avoid putting anything important in the corners. Steve D might be able to elaborate on this, but I don't think they tried putting anything like icons in the corners 'til the 90s.

Charles

I recall back in the late'60's when rectangular color sets were starting to outsell roundies, our directors would still make sure pictures were framed so that nothing important was cut off on a home roundie color set. This was especially critical when producing commercials. After all there were thousands of round tube color sets in use well into the 80's.

-Steve D.

Yep. The Japanese did studies on the best frame shape for HDTV, and came up with 15x9 IIRC, later modified to 16x9 for mathematical elegance Veddy Intaressting as Arty Johnson used to say. Didn't know what more there was to it than the 3^2 x 4^2 bit.

As was mentioned earlier, the extra difficulties with convergence and pincushion presented by a rectangular tube were the reasons the first color sets were round, not an inability to blow a rectangular glass funnel.

I think a rectangular screen's surface is "spherical" just like a round screen's one... the only real difference is the shape... early rectangulars also had more or less the same curvature radius as roundies...

actually, one could say that a 21 inch rectangular screen is just a cut out section of a larger 21 inch round screen

i don't think the difficulty into making a rectangular screen is a matter of pincushion corrections, it's more likely a matter of easier shadowmask and phosphor dot screen construction...

The real challenge with pincushion correction and convergence came out with 110 degree color CRTs, earlier 90 or 70 degree tubes were much easier to drive... and for this very reason many late cheap sets are going back to 90 degree CRTs...

I think a rectangular screen's surface is "spherical" just like a round screen's one... the only real difference is the shape... ..

True in part, but there are a whole bunch of considerations -
Corner convergence;
Bulb strength;
Corner purity - which is related to brightness gradation:
To make obtaining purity easier, the shadow mask holes (or equivalently, the black matrix holes) were made smaller towards the edges. This was done so strongly on some rectangular designs that people complained that there was a bright area in the center of the picture (this was not a sharp-edged area, just the gradual variation from center to edge). Due to the lack of low-frequency response in the human visual system, you can get away with some of this, especially when the picture is viewed up close - but from far away it's more noticeable.

Later tubes were designed with flatter faces, making all the problems more difficult.
By that time, stripe screens had replaced dot screens, allowing self-converging yoke designs. Since vertical beam angle does not affect purity on a stripe screen, that degree of freedom can be used to help get convergence, and the convergence circuits can be eliminated.

Some early 70s 110-degree In-line CRTs like Toshibas, the GTE-Sylvania Uniline, and the Philips 20AX weren't self converging, they still had convergence coils on their necks and required a convergence circuit with lots of adjustment knobs just like delta gun CRTs...

Self converging "Precision in line" tubes (RCA) which were the first to do away with any kind of convergence circuit in the mid-late 70s, had a finer stripe pitch in the center of the screen, and a quite coarse pitch at the sides, unlike earlier inline CRTs which had a constant stripe pitch all over their screen

as for bulb strenght, the real challenge was posed by early 110-degree B/W CRTs, as the flatter bell and increased vacuum would put a lot of strain on the edge of the screen, so early 110-deg tubes were very fragile and dangerous, but by the time the first 110-degree color CRTs came out in the late 60s, the "tensioned rimband" integral implosion protection had already been invented.

In fact, a good CRT (both 90 or 110 degree) with a serious tensioned rimband is extremely safe, and does away with the need for bonded lenses or separate safety glasses... actually, you can't get one to implode even if you smash it with a hammer... it will just break where you hit it and quietly lose the vacuum through the hole.

Hey: Old_TV_Nut's avatar roundie is changing pictures every few seconds! Neatest thing I've seen on an avatar! How'd you do that?

Charles

Hi Charles,

Hey: Old_TV_Nut's avatar roundie is changing pictures every few seconds! Neatest thing I've seen on an avatar! How'd you do that?

He has created an animated GIF file. You can do it also with GIFconstruction set or The Gimp. Both are free.

- Eckhard

Hey: Old_TV_Nut's avatar roundie is changing pictures every few seconds!
It is an animated GIF file. Do a Google search for "animated gif."

Phil Nelson

Hey: Old_TV_Nut's avatar roundie is changing pictures every few seconds! Neatest thing I've seen on an avatar! How'd you do that?

Charles

I would be glad to make one for you - just send a $20 bill taped to the bell of a working 21AXP22A :D

Animated GIF's are easy to make, if you have the right tools.

Hi,

send your images and your wishes to me, I will create you an animated GIF for nothing.

- Eckhard