Hello! I am regularly teaching video production and often I get this question: "So if my Canon T2i is full HD, why do people use more expensive cameras?"

I am therefore looking for good web resources which explain these things in an AN EASY WAY: resolution, bitrate, compression, codec, color space, color subsampling, artifacts and moire. Can you recommend me some?

Most of the web resources I have seen in these areas quickly get so complicated it is impossible for any beginning student to understand anything or feel motivated to learn more.

I am also looking for a website that does a comparison on cameras in the mentioned areas.

Thank you in advance!

1) By "more expensive cameras", do you mean more expensive SLRs or real video cameras which would cost more than a 550D?
2) The term 'Full HD' is meaningless in any discussion about video quality. I have a 550D/T2i, and whichever lens you put on it, the image has a maximum resolution of about 600 LPPH (lines equivalent) as its sensor reading method is chosen as a cheap add-on to the processor rather than a serious attempt to create HD video. The much hyped 'Full HD' figure of 1920x1080 samples is technically correct, but intended to mislead those who are attracted to big numbers in specifications.
Unfortunately, much of the web content on SLR camera video performance is either fairly non-commital about HD performance, or is wallowing in a delusion of 'cinematic' opportunities that fail to mention the soft images littered with moire and other crude sampling artifacts. So I don't think you will find much in the way of objective resources online.

An objective resource online is the original vision for DV Info Net.

Hello! I am regularly teaching video production and often I get this question: "So if my Canon T2i is full HD, why do people use more expensive cameras?"

I am therefore looking for good web resources which explain these things in an AN EASY WAY........
Can't help you with a full list of web resources, but can give an analogy which hopefully you may find helpful.

As regards the question, the reference to "full HD" of the T2i relates to RECORDING FORMAT, in fact just to the resolution (1920x1080) of the format. (It doesn't say anything about compression.) Recording format and front end camera quality are two separate things.

Try comparing the "full HD" format to a container with liquid in it. You may have a one litre container - but that is not to say it must have 1 litre of liquid inside. Without opening or weighing it, all you can say about the contents is they cannot be MORE than 1 litre. And in the analogy, the volume of the contents represents the resolution of the camera. (Which is exactly as Steve says. I've also got a 550D, and whilst half of me feels it's better than I have a right to expect for the money, the other half knows very well that in no way is it close to the performance of a more expensive, true video camera.)

Using the analogy, the container is half full.

Is that of any use?

I agree with Chris. DVInfo has a wealth of knowledge unlike anywhere else. The quality of the people in this community is unmatched. Any research I have about equipment, technique, or anything else always begins here. I've literally spent hours at a time when I'm researching something important to me.

Any student who has any real interest in learning more could easily be drawn into the discussions here and find all their answers. Even if they can't find an answer in old posts, it seems someone is always ready to provide an answer in a new post!

1) By "more expensive cameras", do you mean more expensive SLRs or real video cameras which would cost more than a 550D?
The latter.

An objective resource online is the original vision for DV Info Net.
Are you referring to an article?

I'm referring to the overall scope of the entire site. We can always use more articles. We're always trying to grow that section -- see Articles & Reviews at DV Info Net (http://www.dvinfo.net/article)

I think the best answer is let them try to do real work, under real pressure, with a consumer DSLR and with a real video camera with proper controls, audio input and monitoring, physical and well as image balance , proper viewfinder, etc. I have a Nikon D7000 and would rather have sand thrown in my eye than to try to shoot a real ENG story with it, particularly if I could have a decent (preferably shoulder-mount) camera from Sony, Canon, Panasonic, or JVC to work with.

(Not to dump on the Nikon, or Canon, or whatever. Yes, it is capable of making a usable video image. Like the singing dog, the wonder is not that it does it so well, but that it does it at all.)

Yes, there are people doing serious work with DSLR, but when you look at them they have a ton of bells and whistles hanging off of the camera trying to make it work like a "real" (my words) video camera. Proof is in the doing.

For students, keep in simple, and use analogies they might understand - something like "you can get from point A to point B on a bicycle, or a VW bug, or a Mercedes... or a train or airplane" Why might one choose one over the other?

That should make their brains either explode... or open up to the idea that just as there are MANY different considerations in choosing transportation, so too there are many ways to capture an image, with many potentially varying levels of quality and ease of use...

And yes, a link to DVi would provide the collective knowledge of hundreds (thousands?) of active, informed, and enthusiastic camera users familiar with virtually every bit of gear, current or past...

And sometimes we remind ourselves it's the "content" not the gear... just to keep perspective!