quote:

---

I can't imagine that NTSC looks great converted to PAL, with the loss of frames and the such. I know that PAL looks horrible converted to NTSC. All of the British television that I see here looks pretty boring anyway (and no, I do NOT like Dr. Who). I'd take NTSC progressive scan over PAL interlaced anyday. I really do not like interlacing. Progressive scan is sooooo much smoother. I'm sure that none of the current standards can hold a candle to HDTV.

---

About progressive being better than interlaced: Yes, progressive scan will look better if the material originated on film where each field pair originated from the same image or the 3:2 pulldown pattern can be detected so that fields can be weaved together producing a result practically identical to what you'd get if a progressive scan system had been used in the first place.

However, if the material was shot for television using a video camera, and the subjects are moving, then there will be movement between every field. Weaving those together to make a progressive image will cause a "square sawtooth" edge on all horizontally-moving objects, since there will be a 1/60 second temporal difference between adjacent scan lines of the progressive image that is created. To do away with this artifact requires some smoothing or averaging of each pair of scan lines which does away with that ugly artifact at the expense of destroying up to half of the vertical resolution of the image. For such material, it's best to just leave it alone and leave it interlaced. I've seen HDTVs in Best Buy that, when playing interlaced NTSC material, lost half the vertical resultion to give a smooth progressive picture, which was noticeably inferior to the ordinary interlaced NTSC sets sitting next to it. However, this set looked beautiful when DVDs were played since the 3:2 pattern could be utilized to make full-resolution progressive frames.

 |  IP: Logged

Yea but when CBS won approval it really pissed the General off and kept him and all of RCA Laboratories at bay for a couple of years till the FCC retracted the approval of the CBS colorwheel. Oddly RCA wasn't really ready to properly demonstrate their system yet when the colorwheel appeared. They had no tri-color crt ready and the demonstration set they used 3 seperate CRT's. In the two years that the CBS system enjoyed some popularity RCA utilized that time to really perfect their system.
MArk @ GTS

In fact the first Black and white images used a minature version of the image dissector tube for pickup. This is a cold cathode tube(no filament)that has great contrast range although is not very sensitive. It is almost impervious to being damaged(short of being broken).
The original image dissector was invented by Philo T. Farnsworth in about 1926. It was the first operable camera pickup tube ever made that actually could produce a picture. This invention also caused much havock for Sarnoff at RCA as they still had to rely on the spinning disk camera. Later improvements in this tube by ITT made it more compact and higher sensitivity for use on the moon. Not only did it make the camera lighter but it also made it simpler and more reliable. Luckily, before Farnsworths death, he got to see these live TV images beamed back from the moon via a camera that used alot of his original inventions.
MArk @ GTS

It's interesting that the "hottest", "latest", "high-tech", (etc), DLP technology uses a single MDM chip and a spinning color wheel to keep costs and size reasonable. Brings back memories of the aluminum xmas tree....

>>> Phil

By the way, if you thought color wheels were cool, just wait till you see a nipka(sp?) scanning disk camera and receiver. it was very similar to the Baird scanning system. there was also a prismatic system, but all of these went out the window when we found a vacuum tube that could produce a watchable picture.

Josh

 |  IP: Logged

Like the so-called "projectionists" in many neighborhood multiplexes these days, the talent level of VCs (assuming there are any VCs on staff) in local-market broadcast TV, industrial TV, or even network-level sports TV, is generally pretty low. Why? Because these segments of the professional video world are entry-points, places where dues must be paid and experience gained before one can move on to industry segments (such as freelancing on network-level shows) where the production standards (and pay rates!) are much higher. Most of the engineers that work in these aforementioned segments are newbies talent-wise, even the ones that have been there a while (the ol' first year of experience, repeated for 20 years syndrome). These folks' newness is betrayed in the pictures they make.

If cameras don't match after being aligned on a waveform/vector scope, it's because the individual encoders haven't been fully aligned. If the cameras don't match on the chip charts even if their internal bars match on the scopes, it's because the cameras haven't had their grey scale tracking fully checked. If the cameras don't match even after the bars match, and the chip charts match, that's to be expected due to lens flares, which must be "painted" on the fly for high quality production anyway. Painting blacks, watching detail level (the required amount varying with lens zoom and iris position), and watching SCH phase is most of what a VC does, along with the basics like iris and black levels, during actual production.

Often in these entry-level industry segments, production budgets don't allow for a separate VC, that duty falling instead to a studio/truck maintenance engineer, who may know the hardware but still not have the eye. Or even worse, VC gets entrusted to automatic circuits (auto-iris, auto white balance, auto black balance). Even if a real VC is budgeted, the production facility itself often lacks a real VC work position (i.e. no contaminating light, with a separate, real match monitor and switcher). As always, one gets what one pays for. Non-aligned cameras will look just as "bad" regardless of the format, be it ATSC, 601, PAL, SECAM, or NTSC in any of their flavors.

Jeez, that sounded like a rant. Wasn't meant to be. Just my 0.02USD. Cheers!

Paul
Mercenary film/video projectionist/engineer
"When the money runs out, so does I."
Member SMPTE Hollywood Section
Back in 'Vegas, still looking for something to do

 |  IP: Logged

 |  IP: Logged

 |  IP: Logged

 |  IP: Logged