A tv set does not show 100% of an image, it's not supposed to, never was. Only about 93% of the inner portion of the image makes it onto the tv. That outer 7% is often filled with noise and may lack picture. And it is NOT the same on all sets, some are less, some are more, but it's always in a 5-10% area, no more than 2-3% margin of variation.
The computer allows you to see 100% of the image.
This leads to problems....
DOWNLOAD FILE TROUBLES:
You have "downloaders" which are stupid, because they crop the image when they encode and upload online. They SHOULD HAVE just covered it over with a black mask of a few pixels on each side (cover it, hide it).
People that download these files usually continue being stupid, and do not restore the overscan. So the DVDs made from download files are missing about 5-10% of the image. That number may seem small, but it's very easily noticed, especially when the station ID logo is half cut off down the screen. It's as bad as watching the fullscreen version of a widescreen movie, where you can have action and whole characters cut out of scenes.
See this guide here for information on how to re-encode downloads to MPEG-2 with proper methods, restoring the overscan: http://www.tvpreservation.com/forum/...peg-2-583.html
DVD MENU TROUBLES:
A lot of people sit at the computer and make what they think is a really nice menu, only to burn it, and part of images, buttons and words are totally cut off the screen. Oops. Sadly, some people are stubborn or lazy and never try to correct it.
To illustrate how menu overscan works, I'm going to pick on myself and on markatisu, as we both made these mistakes at the very beginning of our DVD-making days.
In 2001, I sat down with my $800 burner and my $9 each Pioneer blanks. I pounded out what I thought was a beautiful Robotech the Movie menu (and I still very much like it).
It was supposed to look like this. That's what I saw on my PC screen.
I burned my $9 blank, and to my horror, I saw this on the tv:
At the time, DVD-RW was still new and cost about $25 each, so I didn't own any. But I went and bought one, much to the chagrin of my checkbook, and experimented until I learned on my own how to fix this. You see, back in those days, stone ages of DVD tech, nobody had "guides" online, nor were there any books in stores. Anybody that started this in 2003 or later is really lucky, and should remember that, with the abundance of software/info and low prices of media that exist now.
I created this template, a PSD file I've had for 4 years now, to be sure I never "messed up" again:
I re-did the menu, like so:
Note: for those of you not familiar with Photoshop, all the blue lines you see are guides in the software, they are not saved visibly onto the image, they can only be viewed in Photoshop (and when turned on).
As you can see, the menu is correct. Nothing was cut off.
Now it's time to pick on markatisu, and one of his first sets, the Aladdin DVD series. He made the opposite error, something that shoul have been partially off the screen was not, so it looked bad. Remember how I said earlier that "overscan can range from 5-10%, not all tv's match" ?
Markatisu made this menu:
But this is what was seen on tv:
Not a pretty sight. The text on the right was cut off, and the image on the left showed the outer border, which should have been bled off screen.
Bled? Bleeding is a printer's term, it describes printing something slightly larger than the paper, so you ensure that ink fully covers the entire piece of paper.
Let's go ahead and look at this example from the printing point of view, using a standard 8½x11 piece of paper, and printing a photo from your printer. And let's say we're printing a picture that is to be framed and hung on the wall. Which looks better?
The image that still shows the paper... (no bleed)
... or the image that is just the image? (bleeding)
Now let's apply that to the DVD menus:
In order to ensure you do NOT see the outer edges on any tv set, be sure you bleed the image. Be sure to pick an image, to where if you lose something from the bleed, it won't make a big deal. Refer back to my ROBOTECH THE MOVIE menu for a minute. A simple gradient pattern was bled, something that does not matter too much, not like icons or words or the bike picture.
I went ahead and re-did the menus on markatisu's Aladdin set (did that yesterday and today, actually):
This is what is now seen on tv:
The "seeing the border" issue is now gone. As is the text spillover.
The more you bleed, the safer you are. I'm probably cutting it awful close here on the Aladdin set, but it's still well beyond the boundaries on all the tv sets I have here, one of which is terrible about showing too much. I suggest bleeding as much as you can.
This may seem like a long read with a lot of pictures, but this is what separates more professional-looking menus from the kinds of crap people like transformersCDs and other puke together with no effort, thought or skill.
These are the skills. Use them..
You can download the PSD OVERSCAN file attached at this bottom of this post.
Also, all menus are designed 4:3, meaning 720x540 pixels. Your DVD software should take them just fine, and in fact, most requires 720x540 or at very least suggest them. Designing at 720x576 or 720x480 is no good, because it's not 4:3 and will stretch out differently than how it was designed.