First question: I have heard that MiniDV use some sort of compression. Is that right and if so, is it lossless or lossy?

Second question: I use mostly Beta SP at my school but I was wondering if Beta SP is an analog format (lossy)?

Third question: What is best – MiniDV or Beta?

Thanks in advance


Martin Baun | Denmark

Martin,

Yes, MiniDV does use compression. You may want to do a search, there are several very good threads with excellent links to additional information on this topic.

Yes, BetaSP is an analog format. Beta SX was the first major Sony all digital format for ENG and better work.

No way to answer which is better, to many factors like where and what are you shooting, what is your experience level, how do you intend to edit, what is your final product format.

BetaSP is a robust but dying format. Minimal support by Sony, no new cams or decks. MiniDV is going strong but has significant limitations in it's current rendition.

Third question: What is best – MiniDV or Beta?Probably beta is in terms of quality, however, it would also depend on the cam behind the format, and most beta cams were higher-end compared with the miniDV consumer cam line.

About the first question I couldn't find any threads that could help me.

I did a little research on the internet and found out that the camera is using the codec called DV25 and is using it just before it puts the data on the tape.

Still i dont know if the DV25 codec is lossless or lossy :(

That was all.


Martin Baun | Denmark

Martin,

Try this!

http://www.adamwilt.com/EBU-DV.html

DV is a lossy format with digital compression. BetaSP is a compressed analogue format. Assuming you have an identical quality camera on the front of a betaSP tape and DV tape, the DV version should look slightly better, with slightly higher luminance resolution, slightly lower noise, and better picture stability.

Both SP and DV exhibit artifacts, but they're very different between the formats, and about as equally annoying.

Graeme

From a quality point of view, I think BetaCam SP is slightly better. I see more fringing or ringing on DV footage when one is shooting thin lines (such as strands of hair or telephone lines), and sometimes angular lines will look aliased.

If you have a solid color for your backdrop the minid-dv may be equivalent or even slightly cleaner looking than BetaCam SP.

I think the UVW-1800 BetaCam SP deck is still being made, so to say no new BetaCam SP decks are being made is a bit incorrect.

From an environmental point of view, camera acquistion on mini-dv requires a lot less tape and plastic per 1 hour tape than BetaCam SP does. From a space point of view, mini-dv is superior than BetaCam SP because the mini-dv tapes take up less space.

My personal opinion is that finished edit masters would hold up better on BetaCam SP than DV-CAM over lets say a ten year time span. But this last point is just an opinion and may not be proveable for a few more years anyway.

In the NLE arena, BetaCam SP may be better for the Avid users, and Mini-DV may be better for the Final Cut Pro users.

Are cable and broadcast facilities actually airing from DV or do they dub over to a more "robust" format?

Well, i am workinking with Beta SP for more than 10 yrs and must say that format is very, very robust and reliable. When it comes to comparing to DV lots of my colleagues thinks that DV is "too small" and there is lot of things that can go wrong (thickness of recorded lines on tape...). When it comes to quality, both formats are capable to record better picture that our consumer TV sets can reproduce. I've seen gorgeous pictures from DV, and very crappy picture from Betacam, and vice versa. It really depends on camera you are using. ie My Canon XM2 has far better picture than UVW100 Beta SP camcorder, but compared to DXC637 or Ikegami HC340 "oldie" Beta SP picture on XM2 is lacking on sharpness, colours etc...But hey! This little cam cost 10 times less than Beta SP.

Alessandro-->
here in Kansas City, i am required to get my miniDV final masters converted to Beta to play on the local cable provider, TimeWarner. They do not accept miniDV or DVD copies.

Martin-->
i have worked with footage in both formats using FCP and i would have to agree with Graeme. both formats have their inherent (+) and (-). both can look equally good or bad.

you will not lose too much by switching over to a DV.

The major difference I see is that Beta SP has better blacks, details in shadow show up. The old 0% vs 7.5%IRE issue. Playing with setup in the DV camera, if yours will allow that, can help.

BetaSP has noiser blacks for sure - as for detail, I'm not convinced. The setup issue is an interresting one - Beta SP being an analogue format should have black recorded so that it is at 7.5IRE. DV being a digital format does not have setup - this is because no digital format has setup. Setup is a purely analogue phenonema.

If you havea switch on your DV camera that records blacks at 7.5, this will produce a non-standard DV recording, that might be cool for you in a particular situtation, but it only going to give you problems when you give that tape to someone else or try to broadcast it - what do you think double setup 15IRE looks like!

Graeme

> DV being a digital format does not have setup -
> this is because no digital format has setup. Setup
> is a purely analogue phenonema.

That is how it should be. However some sony MiniDV camcorders have a stupid digital setup function which I am sure somebody out there might be using.

Now to get back to the topic, at least down here as I understand it all TV stations are migrating ENG to MiniDV. It seems that the only case where Beta SP is somewhat better is when you need to do chroma key... but since that is usually live at the studio it happens before tape anyway. The edge in Beta (no pun intended) is I think due to DV's 4:1:1 color sampling, color resolution is 1/4th that of luma.

Some legacy Beta and MII cameras, VTRs and Avids are still in use, but all seems to be going the way of DV and FCP, with one TV station using DVCPRO50 and most preferring Sony's DVCAM line. I have seen no Digital beta equipment allthough I know there is some and it's used mainly for some TV series production.

BetaSP can be better for chroma key if you don't know how to key DV. With DV, NTSC being 4:1:1 you first need to upsample the 4:1:1 to 4:4:4, and then it will key as well as, if not better than BetaSP. You can take things a step further by inteligently reconstructing a 4:4:4 chroma from DV, which is, for instance, what my G Nicer filter does for FCP and that produces excellent results.

Graeme

7.5 IRE might make an interesting topic of it's own. I think 0 black is a waste on projects that are not completely lit.

Everyday shooting where lighting is not controllable should look better at 7.5 IRE because you eliminate a small bandwidth that usually has no signficance to the rest of the picture and actually distracts from it, but in the process create a richer, slightly contrasty look.

7.5 camera acquisiton actually preserves MORE of the darker tones, then 7.5 in the editing room allows one to crush what needs to be crushed while retaining the essential part of the video.

In other words, 7.5 IRE issues vary on whether one is talking about camera acquisition versus editing room, and I think it's superior to 0 IRE when one is shooting in situations when one can't control all the of the lighting.

7.5 IRE or 0 IRE has nothing to do with the light in a scene or whatever - it's just what voltage you call black. In a digital system, black is always at RGB 16 and white at 235. There is no setup in the digital realm because setup is purely analogue. If you set a digital video camera to record black in a 7.5 mode, black now gets recorded at about 32 RGB, which gives you 16 less brightness values of information to play with, thus reducing picture quality.

If you have an analogue camera and adjust the setup to 7.5 rather than zero, you're not clipping blacks off the bottom, and you're not brightening up the blacks that come through the lens, (so it's not like adding an ultra contrast filter) - you're just recording them at a higher voltage.

Graeme

My ENG camera has both 7.5 and black level adjustment. When I lift the adjustment to a +1 or +2, I definitely gain lower black sensitivity and it's no longer at a lower than 7.5 IRE. The black level adjustment lifts the darker parts of the scene without raising the brighter parts of the scene.

Then when I edit I choose what I want to crush and what I don't want to crush.

I think that's a strictly analogue camera phenonema, and is really a black level ("brightness") adjustment. Although, there was talk of something like this on the Canon XL1 with a similar control. I use an ultra contrast filter to give me more control over crushing blacks in post and this looks great.

Graeme

I was adjusting the black level once and I accidentally left the camera running while I was shifting the black level adjust, when I viewed the footage later I was shocked to see detail emerge on the persons dark suit right at the moment that I lifted the black from the default setting of zero up to one, then to two. The additional gain in detail in the dark areas was significant, so even though I was at 7.5 the additional adjustment of the pedestal was necessary.

The Canon XLS-1 that I reviewed for camcorder magazine two years ago was most definitely too contrasty for camera acquisition. The brights were over 115 and the darks were almost to zero IRE, this will cause one to lose precious data in the dark areas of the scene. The good news is the Canon XL1-S allows you to save different settings that allow one to lift the black level.

In my opinion Video acquistion should always be about getting as much of the visual information as possible by reducing the contrast. Contrast reduction is achieved by lifting the black levels when shooting, then reducing or redefining contrast when one is editing.

Agreed - as I say, that's why I use the ultra contrast filter as it gives me more room in post.

The comments on the Canon are interesting - DV should have black at IRE 0 - that's digital video for you. Was it peaking at 115 even if you're just hitting zebras at 100? If it records accurately, although illegally in that range, can it not give you more room in post if you've managed to record a wider dynamic range? As long as you don't just clip the whites, it could be advantageous, and indeed is this not what the cine-gamma on the DVX100 does?

I sounds like having a pre-tape brightness control would be a useful addition to any camera to help with difficult shots. I wish the affordable cameras had a lot of more controls in this area as it would really allow you to get the most out of filters and difficult lighting, and as you say, expanding the contrast range that is shootable without clipping.

Graeme

<<<-- Originally posted by Graeme Nattress : can it not give you more room in post if you've managed to record a wider dynamic range? As long as you don't just clip the whites, it could be advantageous, and indeed is this not what the cine-gamma on the DVX100 does?
Graeme -->>>

I think it may work the opposite way. Pull the darker parts of the scene up when actually videotaping, then readjust the final contrast values when editing.

The key is as you said, don't clip the whites and don't excessively crush the darker part of the scene when actually videotaping.