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Posted by mv on 01/11/06 14:29
In message <mma9s1tp73i2e7lehvvkq0v8hkn8nmse59@4ax.com>, none
<Vampyres@nettaxi.com> writes
>On Tue, 10 Jan 2006 12:56:45 -0500, Rick Merrill
><rickZERODOTmerrill@NOSPAMgmail.com> wrote:
>
>>mv@movingvision.co.uk wrote:
>>
>>> Whilst as a rule of thumb it's true that the bigger the chip the better
>>> the image, the argument breaks down when comparing early 2/3rd CCD's
>>> with the latest HAD 1/3rd types.
>>>
>>
>>That is EXACTLY what i wanted to know! Thank you.
>>
>>> 'None' suggests that his old tube cameras and even a DX3000 make better
>>> pictures than contemporary CCD's, I guess he must be comparing with
>>> Samsungs 1/4 inch consumer DV's then? Even the original VX1000 with it's
>>> three 1/3rd inch CCD's reveal the DX3000's antediluvian abilities. The
>>> HAD CCD's used in cameras like the PD170 for example exceed the
>>> capabilities of any 20 year old type. Currently the latest generation of
>>> 16x9 1/3rd inch Super HAD's as used in the Sony Z1 have closed the gap
>>> with most of the older generation 2/3rd types (even surpassed in some
>>> respects) to a point where only the most nit picking would care.
>>>
>No, I have no contention that today's chipsets are better in many
>respects than earlier larger one's.
>The real problem in shrinking down chips is having to use all sorts of
>enhancement technology to clean up the image which can often add noise
>ect.. of it's own. Using those older larger chips allow for as little
>image "doctoring" as possible.(yes some of the early chip cams did use
>comb filtering but most of my early 3 chip cameras allow for the user
>to turn that feature off.)
>It's almost always better to do any tweaking post using SEG hardware
>or as today in the digital domain.( internal camera electronics have
>seldom ever matched up to the quality or adjustability of "post"
>hardware.)
>Brush up on chip technology, the smaller you make them the more noise
>you tend to get.
>
>
>>> Size continues to matter, but technological advancement matters more.
>>> Looks like the CCD as we know it is about to pass into the technology
>>> bin anyway, just as nones silly old tubes have. CMOS is the next
>>> generation. Amongst other types, we have one of the new Sony A1's with a
>>> single CMOS chip. If this is what a first generation CMOS type has to
>>> offer from such a tiny cheap bit of equipment then the writing is
>>> clearly on the wall.
>
>Better read up on solid state imaging history, the cmos came first.
>(We were using cmos sensors in spy sattelites as far back as the
>70's.)
>From what I gather the reason they've re-emerged is improvements in
>sensitivity/resolution and color fidelity and the simple fact that
>they use much less energy to do the job.
>As for tubes being silly, they still can and do produce a video image
>that to many is much preferred.( my best broadcast tube camera
>produced nearly 800 lines of resolution and that was 20 years ago.
>And they have the nerve to call 850i "high def".)
>>>
>
High resolution at the front end of TV cameras is nothing new. Many
people get confused by the specifications given with modern SD broadcast
cameras that sometimes quote figures of over 900 lines (DVW790 for
example). This of course has nothing to do with what's actually recorded
to tape. No SD digital format can exceed 540 lines, whether it's a PD170
DVCAM or a DVW 790 Digi Beta. Clearly line resolution is not everything.
Of all SD formats it's actually PVW Beta SP that's recorded the most
lines to tape, using a Thompson studio camera multi cored to a Sony
PVW2800 Beta SP, 720 lines were recorded to tape as counted on a
standard test card. (1992, HTV UK Engineering evaluation tests. PAL)
The issue of CMOS technology being developed in the 70's is a non
sequiter similar to saying that current digital technology is merely a
development of the WWII Bletchly Park decoding computer made possible by
Alan Turings invention of binary code in 1940. The current CMOS
technology is more a by product of the bizarre partnership of Arriflex
and Lockheed Martin in creating the next generation of 'Super HD'
allegedly capable of 5,000 lines, equivalent to 35mm film.
--
John Lubran
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