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Re: Reccomending a monitor?

Kelli Halliburton wrote:

>Michael J. Mahon wrote:
>>> The other issue is if the 80 columns are interlaced or not.  The
>>> standard composit output from the Apple is 30 frames (not 60)
>>> interlaced.
>>
>> No, the Apple II video is 60 fps, non-interlaced.

Actually, David Stark wrote the >>> part.  I wrote the >> part.

And 60 fps in the case of non-interlaced video is "frames",
since for non-interlaced video there are no "fields" (or the
field is identical to the frame).

>No. NTSC video is 30 frames per second interlaced, which works out to 60
>FIELDS per second. The reference to 60 fields per second (an interlaced
>frame consists of two fields) is probably what inspired the earlier poster's
>correction.
>
>Apple II video is NTSC video, because it can be output to any NTSC
>composite, or monochrome monitor.

Apple video is _close_ to NTSC, in the sense that it will work with
an NTSC-compatible monitor, but it is _not_ NTSC, since it is
non-interlaced.  It also differs from the NTSC standard in its
blanking and sync pulse timing--it's just "close enough" to
work on almost anything that NTSC works on.

>And I use the term "NTSC monochrome" advisedly, to indicate 525-line,
>30-frame-per-second, interlaced monochrome video. I would also use the term
>"PAL monochrome" in the same context to indicate 625-line,
>25-frame-per-second monochrome video. Of course, we could always adopt HD
>nomenclature, and say 525/60i and 625/50i.
>
>HDTV terminology deals with the smallest vertical refresh unit, which is a
>frame in progressively scanned video, but a field in interlaced video, and
>indicates the method of scanning used as the last character, so a
>progressively-scanned image at the same resolution and frame rate would be
>625/30p.

I agree that this is the standard terminology.

The OP's major error was in thinking that the Apple II video was
interlaced, which it is not.

-michael

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