dvdmax & overscan

[theeraver]

Hi,

I read postings on this forum and matrox forums about this subject but really couldn't understand the explanations. Someone please inform me about this.

I have a brand new 27'' sony tv (ntsc) and G400MAX. I have no cropping problem if i use the tv with a regular standalone dvd player or a vcr. But if i watch a movie with mediaplayer, realplayer or quicktime in dvdmax mode, i loose at least 10% from four sides of the picture. if i use clone mode, of course this problem doesn't occur.

Actually the main reason why i don't understand the issue is matrox tech people say this is normal and the problem is tv. Then i want a explanation why does the same tv works in clone mode or with a regular standalone dvd player or a vcr.

What is the difference in signal between clone mode and dvdmax that causes this problem?

Please let me know if there is a solution for that.

And also i would like to know if there is any tv that doesn't have this problem with dvdmax mode.

Best regards to all for the new year.

,thee

[This message has been edited by theeraver (edited 27 December 2000).]

[Dr Mordrid]

If you're saying that you lose 10% from the side of what is visible in your captures then yes, this is normal.

A Marvels full frame 704x480 capture has a 4.4:3 aspect ratio. A 720x480 frame, as used with miniDV and DVD disks, has a 4.5:3 aspect ratio. Your TV screen has only a 4:3 aspect ratio, somewhat narrower, which is why the sides of the other signals are cut off. This extra data, the overscan, is there to compensate for TV's that may be out of adjustment, mainly in the horizontal.

The visible zone inside the whole frame that always shows on a 4:3 display is called the "title safe area". This is because titles or graphics placed in this zone will not be cut off by the loss of the overscanned data. It's also the area you should mark off on your cams LCD so you can properly frame your shots. I use an acetate sheet slightly larger than the LCD marked with a thin marker & taped to the LCD's frame.

This site will explain overscan in more excruciating detail;

http://www.geocities.com/ResearchTri.../overscan.html

When you put it into Clone mode the overscan may be getting squished to fit into a 4:3 display, albeit with some minor (and likely not very noticeable) distortion.

Dr. Mordrid


[This message has been edited by Dr Mordrid (edited 27 December 2000).]