On Wed, 17 Jul 2002 00:49:10 +1000, "Hughy"
wrote:
>
>Thanks,
>
>So you believe further improvement to the VX2K lens won't produce much
>return - but real improvement to the final image is more likely to be obtained
>from better CCD's in the VX3000?

Yes - that and better associated electronics. As it is now,
the VX2000 image is about at the resolution limit for the
format, and the color, contrast, and other picture aspects
are also about maxed in quality for the format - and the
picture artifacting is *relatively* minimal for the format
compared with other Mini-DV camcorders, but still at
annoying levels for some of us with some types of lighting
and subject characteristics.

>Does this mean the 25 Mbit format is
>approaching it's performance limits?

It would be interesting to feed a very high quality image
from a large camera to the Mini-DV recording section to see
if it would be relatively free of the artifacting problems
(actually, simply reducing the contrast [which bigger-CCD
cameras can do] would likely alone reduce the artifacts...).
I'm not yet convinced that all the artifacting we see in
Mini-DV is the result of 5:1 compression, though some of it
obviously is (mosquito noise, especially), and it may be
that a cleaner, "quieter" picture is possible with D25 than
we have seen so far, without having to go to D50...

>Looks like narrow end diffraction also explains the problems one gets with the
>XL1 if you let the aperture go out to f32, which it can do on auto settings
>(we much prefer to use XL1 aperture priority when shooting outdoors to stop
>the problem, rather than ND filters).

Yes. The picture would soften noticeably, though with my
old PC1 which could also go to f32, the results weren't
as bad as one would expect (the video medium is less
critical of resolution than some higher image quality
media, like even 35mm - where f32 can be disasterous
for image sharpness). With the VX1000, I used to use
AE-A to specify a good aperture (especially when using
WA converters), but with the VX2000, while differences
between f1.6, f4, and f11 (the smallest available stop)
can be seen, they are relatively subtle differences
(even with WA converters, if they are good), and often
more than acceptable...

>Regards,
>Hughy.

>"Neuman - Ruether" wrote in message
>news:3d361beb.3545700@newsstand.cit.cornell.edu...
>>
>> On DIFFRACTION in Lenses...
>snip

>> On Tue, 16 Jul 2002 22:55:18 +1000, "Hughy"
>> wrote:
>>
>> >OK - I'll 'fess up.
>> >
>> >Tell me about "diffraction limiting" ..... in *very* simple terms if
>possible,
>> >please David.