Bob is absolutely right, when it comes to "spatial resolution," the term "resolution" is much more complicated than just measuring pixels.

Thank you Bob, John, and Coursedesign for the additional info and explanations. It's nice to have such good resources in this forum.

-Steve

I've never had a problem with failures of DVD or CD media.
Then again I buy the expensive media by defaul and for critical media storage I buy the very expensive gold media.
On the other hand I've made good money dealing with old video and audio tapes sticky shed syndrome. Clients have lost slides and film to vinegar syndrome and fungus.
The thing is with some effort digital media can be keeped in pristine condition as there's no generational loss. Analog and chemical storage simply cannot avoid degradation over time and generational loss. Our ability to store mind boggling amounts of data in multiple geographic locations adds further to our ability to archive everything for future generations.

To me a more pressing question is will anyone care. Future generations will be inundated with information. What we lack is the technology to catalog it, to sort it. It may well be all preserved and available for instant access but it becomes moot if no one is able to sort it.
On the other hand with the old analog formats probably only the material worth saving will be saved.

Bob.

bob,

That is a good point about too much information. We enjoy the past archives because, relatively speaking, it is rare. Future generations, if the storage media holds up, will have more information than they can handle.

I guess in my next life I will get to witness that. ;)

Dave T2

"Rob,

There has been much debate on exactly what these consumer cams shoot. Truth is nobody knows for sure. What I do know is that I've seen claims of "60p" out of some of these cams... and it doesn't take a brain to notice something sadly wrong with the.... "60p" that they produce

I've seen claims of "FULL HD"... written right on the side of my little HC3 and HV20 cams. Funny thing is, last time I checked these cams were HDV cams (HDV does not make full hd).

When the HV10 came out they advertised "full 1920x1080" but what they didn't tell the poor fools that didn't know any better is that you can't get 1920x1080 on to tape.

I've heard all the arguments and debates... even heard David Newman from cineform call this stuff "real".... and still I'm not at all convinced that these little cams shoot anything NEAR the REAL progressive that one speaks of when talking a more serious cam.

To top it all off... I quite agree with John Cline in that progressive at present is simply lacking and will continue to be so until a real 60p comes forward. It will offer the temporal resolution that is comparable to its interlace counterpart.... without the interlace flicker. This will be a true advancement. But this 24/30p rubbish (which is SUPPOSED to look more like film and doesn't come anywhere close) is little more than a progressive attitude at the expense of time. I see absolutely no gain here.... other than a more complicated workflow in trying to unseat and remove the pull down

Pulldown is primarily for tape, and for hooking up a non-24P-capable monitor to the camera.

The progressive from the prosumer level cameras really looks very decent.

And the $150 Kodak Zi8 in good light? Shockingly good 1080P quality, and real progressive to boot, with no pulldown recorded to the flash card.

Yes Course, I'm quite perfectly aware of what pull down is used for and it is not 'primarily' for tape. You will find it even more so on the avchd cams.

But alas none of that matters anymore. You have suddenly convinced me in the err of my thinking ;)

Thanks for all the input. From all of this I guess formats are in a transition phase that may take some time and there are no clear cut answers. Things look like they are evolving towards progressive but unless you can afford a more advanced camera then it doesn't seem to be fully developed as of yet (from what I read in some of the posts). It seems as though progressive has its own problems, just different from interlaced. I have a CRT monitor and TV but do not use them for video. I have a lcd monitor on my editing computer which is also connected to an lcd TV. I've had a Digital8 camera for the past 8 years, before that Hi8 and before that just 8mm. I have trouble getting 8mm tapes now so going with another tape type camera seems like a poor choice.
I would like to know why Sony chose to have all their consumer cameras record interlaced video if its so bad and outdated. Is it cheaper? Are they lazy? or maybe interlaced video isn't as terrible as some people say. I don't know. I keep my cameras for a long time so I think a lot about what to do beforehand. Again, I appreciate the help in trying to clarify all this information and new technology stuff that's available today and what to expect in the future.
I have some old Super 8 tapes I'm going to get transfered soon. We were thrilled back then just to see ourselves projected on a screen and having a lot of fun with it. Technology advances can be fun but can also take some of the fun out of it. Looking at all the specs and overanalyzing everything is a downfall of mine. I guess the only answer is to just go with something, make the best of it and have fun.

Joejon,

Interlaced is not as horrible as people think. It has served us well for as long as TV has been around. There have been many thousands of hours of entertainment and high quality viewing with interlaced. It's time has come though. But I think people are moving in the wrong direction. I don't want 24 frames per second, I want 120 or more. I want as many frames as the bandwidth can handle. I don't like flicker or the simulation of film flicker. My eyes see in analog just like my ears hear in analog. I want as much constant input as can be done.

Dave T2

24P is an aesthetic.

It creates a different feel, a slightly hypnotic state, like the flickering of the light from the fire and the shadows on the cave wall, as the story teller brings the audience into his world for a moment.

"I don't want 24 frames per second, I want 120"

Actually we take sensory inputs as samples rather than continuously, so there is a limiting frame rate beyond which you couldn't see the difference. How fast is that? "The key to passing the Graphics Turing Test, says McGuigan, is to marry that photorealism with software that can render images in real-time - defined as a refresh rate of 30 frames per second." [New Scientist; 3 April 2008: 'Matrix-style virtual worlds 'a few years away' ]
Now, just as my stereo vision extends well beyond the 3 metres usually accepted as its limiting range, so there are people who don't see 30 frames/sec as continuous motion.

Regarding the hypnosis of 24fps, I'm not sure. Of course presented with only 24 images per second everyone will see objectionable flicker. Film has a refresh rate of 48 Hz and mostly monitors are set to much higher refresh rates (modern TV is commonly 100 Hz and higher). The perception of flicker and the interpretation of a series of images are different phenomena.

As computer display cards and CRT monitors were evolving from CGA through EGA, VGA, SVGA and beyond, the question of refresh rate also surfaced. Back then common wisdom was that you should use a refresh rate of about 70 (progressive frames) per second if your equipment would support, it in order to avoid eyestrain due to flicker. (I think EGA also had an interlaced mode for its highest resolution). A longer persistence screen would permit a lower refresh rate for the same amount of flicker but was less suitable for watching videos or playing games.

So I think 70 progressive frames per second might be the sweet spot or the point of diminishing returns.

Coursedesign,

I guess I have never actually seen 24p since I have only watched movies on TV or in a theater (which some are saying is actually shown at 48). But I was in Ireland where the frame rate is PAL and the flicker drove me crazy. I don't really buy the idea of 30fps being our normal perception either because I saw a monitor that had no persistence running at 30 and it flickered madly. The reason we can watch 30 (which is actually 60 fields per second) is because of the persistence of TV monitors.

Now I know PAL countries get used to the flicker and probably don't notice it, but I was very aware of it. Maybe I am one of those people who are sensitive to flickers.

My optometrist always accused me of wanting to see better than normal.
Dave T2

"[i]Now I know PAL countries get used to the flicker and probably don't notice it, but I was very aware of it. Maybe I am one of those people who are sensitive to flickers[/I]"

You're not an exception in this regard, Dave. With older plasma TVs here in Europe that could only refresh at 50 Hz, the flicker was unbearable to most people. This is why most HDTVs refresh now at a minimum of 100 Hz (200 Hz being the current standard).

We must differentiate in this discussion between refresh rate and FPS. For the two to go together well, the former should always be a multiply of the latter - so for a 25 fps progressive material, it should be 50Hz (flicker), 100Hz (ALMOST no flicker), 200Hz (steady as a rock).

My current Panasonic Plasma displays my 1080/25p material at 100 Hz, and I really have no complaints whatsoever.

AND, I do see the spatial resolution loss with 1080/50i stuff. That said, I can imagine situations when I'd rather go 50i over 25p (fast pans), but with what I shoot mostly, it almost never happens.

Dave T2, cinema projectors run film at 24fps and have a two bladed shutter. So each frame is shown twice. In image highlight areas (when the screen is bright) flicker (perception that a light is not constant in brightness) can be seen, particularly in your peripheral vision (which is more sensitive to this sort of thing). Whether you perceive as continuous a series of rapidly seen images depends on different phenomena, and this might help http://en.wikipedia.org/wiki/Persistence_of_visionhow you see[/link].

Wow, now I know my head is going to explode ! After reading countless reviews, it seems that I have almost made up my mind. Let's recap.

1) Progressive recording allows for easier editing versus interlaced.
2) MiniDV tapes can be somewhat less stable (depends on who you ask) and takes a long time to capture. Flash on the other hand, should be around for a while.
3) Progressive cameras cost anywhere from 2.5K to $28,000.00. (I want one of those).

The HD40 states that it records in both formats and Sony (HDR HC9) says that it has "Progressive Scan Performance while utilizing an interlaced scanning system". Sound like they want to be progressive.

I have spent a fortune on my PC and want a good consumer camera now and will be looking for a Prosumer after Christmas.

Does anyone have some suggestions? Ease of editing and good media shelf life is needed.

Take Care,
Aaron

Being able to watch 24p is an acquired skill. We've all been watching 24p movies since we were little and our eyes and brains have all grown accustomed to the corrections they need to do in order to not be driven nuts by the judder. Some day in the future, a generation will come up that has not grown up with 24p. When as adults, they find some old 24p movies and try to watch them, I seriously doubt they will be able to stand the judder. 60i will look a little soft but still watchable. 24p will drive them nuts.

Just my humble opinion ;-)

So what will we have in the future Laurence? 60p, 75p, 100p, 120p,..?

Remember CRT monitors? (I still have one!) Wisdom said that the refresh rate should be at least 70 Hz and preferably higher to reduce eyestrain.

PS
On second thoughts I wonder whether interlaced will ever go away. It is an effective way of acheiving a high quality-datarate ratio.

It [interlaced] is an effective way of acheiving a high quality-datarate ratio.

No, it isn't.

Progressive compresses better with most modern encoders.

It's a given that 1080i60 will have less data to compress than 1080p60 though.

There are a number of considerations for quality: temporal resolution vs. spatial resolution, color sampling (4:2:0 vs. 4:2:2, etc.), color space, ...

Lots of choices, but progressive is also a lot easier to deal with in advanced post production.