Looking bad on television

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Jim Simon said:
24p with sports would probably be weird. Stick with 30i.
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I don't see 30i anywhere on the camera settings or manual? Am I missing it somewhere ? I see that if I turn off progressive I'm back to 60i, which also puts my shutter at a 1/60 default.

So let me see if I can sum up the above recommendations.

Use 60i (since I can't find 30i) vs 24p progressive
Use 1/60th shutter speed to slow action later
 
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Merlin, the DVX100B doesn't have A 30i it's 60i; also I'm not entirely sure why people are saying to avoid using 24P or 24PA to shoot sports I use my DVX to shoot snowboarding,skateboarding and BMX and have been more then happy with 24PA as my shooting format; I could however understand some apprehensions of losing that 6FPS because, in theory it could end up dropping out something but as of yet with 200+ hours of 24PA sports footage I've been pleased.

Most of the reason you want to avoid using the interlaced shooting formats is the artifacting of moving objects, I will say that the 60i mode is pretty good about this but most people I know who shoot or who have shot sports with the DVX just recommended to me to just avoid interlacing all together.
 
30i and 60i are, with regards to the DVX, two different names for the same thing. 60i refers to the number of fields, 30i to the number of frames. The camera calls it 60i, but since 24p and 30p both refer to the number of frames per second, some feel it's proper to stick with that and refer to the number of frames in 60i, which is 30.

The i stands for interlaced, which is a technique developed long ago when television first started to compensate for limitations of the technology.

At that point, you couldn't show the whole frame at once, it was too much information for the broadcast systems. So they split the frame up into two separate fields: alternating lines from top to bottom that, when combined (interlaced) make up the whole image. Half the image (frame) is in one field, and the second field has the other half. It splits the image up into alternating lines kind of like a paper shredder splits paper into strips. One field has the odd numbered lines (line 1, line 3, line 5, line 7, line 9, etc) and the second field has the even lines. Put all the lines from both fields back together, and you have the whole image.

60i is 60 fields per second. When you combine the 60 fields at two fields per frame, you get 30 frames.

Progressive captures the entire frame at once, without splitting it up into two fields to halve the data rate. 60i and 30p both show the footage at the same speed (30fps); the difference is that 30p shows 30 complete frames, and 60i shows 60 half frames interlaced together.

When someone talks about 60i, they're talking about 60 interlaced fields per second. When they say 30i (in reference to the DVX), they're talking about the exact same thing, except that they're mentioning the frames per second, instead of the fields. (Two fields make a frame, 60 interlaced fields in a second (60i) make 30 frames per second (30i)). The i lets you know that it's half frames combined, as opposed to whole progressive frames.

Now, technically, is someone was talking about 30i and was referenced 30 fields, that would be 15 frames per second, but the DVX (along with 99.9% of other cameras) can't record in 15fps.

Now, back to the topic - for sports footage, interlaced is traditionally preferred because it splits the data in half and is therefore faster. Since sports footage contains a lot of fast moving action, it's more taxing on the imaging processors and halving the data rate makes it easier. HOWEVER, if you're doing slow motion or still frames, progressive is preferred because it's a whole image. Think of a jigsaw puzzle - it's the same image as on the front of the box but on the puzzle you can see the jigsaw cuts where the image was turned into separate pieces. When you slow down interlaced footage, you can sometimes see the different fields because half the lines were captured a fraction (1/60th) of a second before the other half of the lines. The most common of these problems (called interlace artifacts) is when a diagonal line in the image ends up looking more like stairs.

You don't have this same problem with progressive footage because it was never "cut up" into pieces. That said, today's processors are usually fast enough to be able to capture fast movement in either progressive or interlaced formats.

Whatever caused your footage to look so bad was probably not a result of the frame rate you chose. Stick with a fast shutter speed and 60i (30i, whatever, same thing) if you want to use the traditional method and you don't plan on using slow motion or still frames. However, you should get excellent results with the DVX whether you shoot in 60i, 30p, or 24p (24p, however, because it's capturing fewer images per second (24 vs. 30 for 30p/60i), will have slightly more motion blur at the same shutter speed than the other two options will). If you're not getting good results, then something else (probably your DVD encoding) is the problem, not the frame rate.
 
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Jeff, that was a spectacular description of 60i and 30i. I'd been confused about this as well, trying my hardest to figure out how 30i could be possible and still look like 30fps.

Thank you so much for describing that in terms I could understand.

When you said 99.99 percent of cameras cannot record in 15fps, I wondered if the Sony DSR-PD150 is one of the few that can? The reason is that I'm finishing up a commercial shoot right now and I'm almost positive it had a 15fps mode. I used it for two shots (interesting motion stuff) with good results. So is that a 15p or 15i? I'm assuming it's a true 15p, which is weird because the damn thing doesn't have 24p or 30p.
 
I'm not personally familiar with that particular camera, but manufacturers have different reasons for including different frame rates. 15fps can be good for low light shooting because it keeps the shutter open longer and lets in more light. However, any movement would appear sped up. You can also double the 15fps in a 30fps time line, making movement go twice as fast (you're showing what used to be 2 seconds of video at 15fps in one second of 30fps).

Some cameras have a dial that can record at any frame rate from 1-60. Some can record at 120 or 240 fps (notice both are divisible by 30 and 24 to make easy slow motion by converting that 1 second of 120fps last 4 seconds in 30fps or 5 seconds in 24fps). Super slow motion cameras can shoot at rates around 1000 or 5000fps, and I just read an article about a new Japanese camera that reportedly record at a ridiculous 5 million frames per second.

As we all know, film is shot at 24 frames per second. All film cameras and some of the new digital cinema cameras shoot at 24fps.

So does the DVX, right? Heh, unfortunately not.

Video has the problem of requiring electricity. Electricity is not steady like running water, it pulses like pumping blood. Until 1953, NTSC video in the US was shot at 30 frames per second (interlaced, so 60 fields per second), which matches the US electric current of 60Hz. You get one field of video with each electric pulse. If you broadcast analog video at a frame rate that's NOT divisible by 60, the image flickers because it's out of sync with the electricity pulsing 60 times a second. This is the same reason it's sometimes challenging to film a CRT monitor or TV without the image on the screen flickering and rolling.

After 1953 a technical glitch with color televisions forced the NTSC standard to be slowed down by .1%, to 29.97 fps. 30p on the DVX100 and almost every other camera is actually 29.97 fps, and 60i is actually 59.94 fields per second.

To be compatible, the DVX (and other cameras) don't shoot "real" 24 fps, either. They shoot 23.976 fps (again, 24fps slowed down by .1%). To do a film out and transfer DVX footage to film (which is really 24 frames per second), the video and audio must first be sped up .1%.

Why is this important? Most of the time, it's not. The camera automatically does the conversions and you can't really tell the difference between 29.97fps and 30fps, or 23.976fps and 24fps. In some circumstances, however (like doing a film out or jamming time code), it's important to know EXACTLY what frame rate you're shooting at.

In Europe, where the electrical current runs at 50 Hz, their cameras run at 25p/50i (exactly). This is why it's difficult to mix footage from US (NTSC) cameras and European (PAL) cameras together, and why you need a special DVD player to play Euro DVDs.

Bottom line is you can shoot at any frame rate, but since all film and video is a series of still images played in sequence like a flip book, we're used to seeing motion (in the US) at either 24fps for film or 30 fps for TV. Slower than 24 tends to look choppy or jerky and breaks the illusion of movement. Some people like to shoot at higher frame rates like 60p because the motion is smoother than film or traditional video. What frame rate you shoot atultimately depends on what looks good to you, and whether you're trying to emulate a certain look (like film).
 
Thanks for all the great replies...I'm learning a ton.

So, last night I shot a football game on 30i with 1/60 shutter. Looks great on the camera, and when I captured it from tape with FCP. I then encoded it with FCP using the below setting:

http://public.fotki.com/photojohnnac/football-dvd-issues/

Importing it into DVD Studio Pro and viewing it on the Mac monitor, it looked fine. However, after burning the CD and playing it on television again, it looked horrible. The football players socks (red) looked like they had a glowing haze around them. I decided to play my mini-dv tape directly into the tv to see what it looked like. It looked the same as the DVD...horrible. On the DVX monitor itself, great. Pumped into the tv monitor..horrible? Still an encoding issue?
 
Merlin90 said:
On the DVX monitor itself, great. Pumped into the tv monitor..horrible? Still an encoding issue?
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I am cruising the forum, anxiously awaiting the arrival of my DVX, but I do believe I can provide some insight on at least this one thread:

My apologies if someone mentioned this already and I missed it, but have you tried a different TV? As someone who troubleshoots things like this, I would suggest ruling out everything, all the way down to using a second set of cables to connect to the TV. Only then can you know if it is from the camera or not.

Karl
 
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Regarding uprezzing SD video, I came across this product http://www.thedeemon.com/VideoEnhancer/ which claims to do as well as Instant HD. Comments? I have, however, come to the conclusion that it just isn't necessary.


Edit: They don't actually claim to be as good but the examples given show no difference in quality that I could see.
 
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Merlin90,

DV does not handle bright colors (like red, orange or yellow) very well. They tend to smear, as you've seen. Go into your scene file and lower your CHROMA LEVEL to -3 or -4. Also, using NORMAL gamma or one of the CINELIKE gammas will help, as well.

I use the following settings and I get what looks very close to 16mm film (I like the "film" look). They should give you a decent starting point for experimenting to find the settings you like best. I have exported to DVD with excellent results that looked really good on widescreen TVs and even projected onto a full size theatrical screen.

DETAIL LEVEL....... -4
V DETAIL LEVEL..... 0
DETAIL CORING .... 0
CHROMA LEVEL.... -3
CHROMA PHASE..... 0
COLOR TEMP......... 0
MASTER PED......... -6
A. IRIS LEVEL....... -3
GAMMA.................. CINELIKE
KNEE..................... AUTO
MATRIX................. CINELIKE
SKIN TONE DTL..... OFF
V DETAIL FREQ...... THIN (for 16:9 squeeze mode)
PROGRESSIVE....... 24P, 24 pA

Use your zebras for exposure. I like the 80% zebra but try both the 80% and the 100% to see which one you prefer. 80% is best for skin tones.

I have a couple of examples of films shot with these settings if you want to check them out:

http://www.youtube.com/user/Paladin0954

The same settings should give you a good starting base for 30p, as well.
 
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