MiniDV vs. Betacam SP for 16mm format

[Ralph Oshiro]

I have come to the conclusion that these "tests" were done quite a while ago and didn't actually use betacam sp component to either 10 bit or 8 bit uncompressed, or at the very least, the DVC-Pro 50 codec, all of which would be superior to the betacam sp component video signal to DV firewire transcoding option that was used for these "comparisions."

Not sure what you're saying here. Why would the authors transode the Betacam source tape to another format for evaluation? The Betacam signal was recorded on a Betacam VTR, played back on a Betacam VTR, and evaluated on standard terminal test gear. The DV signal was recorded on a DV VTR, played back on a DV VTR, and evaluated using standard terminal test gear. No transcoding.

[Bernhard Zitz]

Or do you mean a DV copy is made of the uncompressed footage (seperate file) which is edited, then FCP takes note of the cuts in the DV footage using the timecode or whatever and applies these same cuts (edits) to the uncompressed footage - sort of like working with an EDL?

 

Yes that's what I mean, sorry my mothertongue is not english, I have some trouble to be exact.

 

It's even more simple than working with an EDL. In FCP you can simply exchange a footagefile with a copy of it, as long it has the same TC and same lentgh, FCP doesn't care if it's a different codec.

 

 

Some crucial questions to the Topic Starter haven't been discussed:

 

What's the desired endformat?

 

If you get the telecine on BetaSP what codec you use to tranfer it to your computer?

[Alessandro Machi]

.........Some crucial questions to the Topic Starter haven't been discussed:

 

What's the desired endformat?

 

If you get the telecine on BetaCam SP what codec you use to tranfer it to your computer?

 

Betacam sp codec to either 10 bit uncompressed codec, 8 bit uncompressed codec, DVC-Pro 50 codec, my fourth choice would be the mini-dv firewire codec. I think DVC-Pro 50 codec is the ideal blend of higher quality than than the mini-dv codec yet it won't suck up a huge amount of memory either. However to have all of these codec transfer options available to you you'll need to purchase either the Kona Card or the Black Magic Card. Remember that if you go directly into the computer at 10 bit uncompressed and bypass making a tape master not only will it take up a ton of memory, one will then have to keep that transfer on the harddrive even after the job is done otherwise if one ever needs to access the original raw footage later on the original film will have to be retransfered again.

 

I would say that if you want to avoid the tape step, then get some type of actual hard drive "video cassette shell" and actually treat the hard drive the way you would treat a video tape. When you are done using that particular drive, actually remove it from your system, put it in it's own case, and store it. Of course you are now on the "bleeding edge" of innovation because how many people out there are doing this type of hard drive storage and HOW LONG have they been doing this. I occassionally use 10 year old betacam sp masters because they have important film transfers on them.

 

What is the desired endformat? That is open to discussion. If you can generate an edit master in the computer that would actually pass quality control for distribution purposes, then outputting directly to digibeta is probably the best format to go to, make a back-up digital betacam "clone" as well and use that to make all of your tape dubs. So why not start in digibeta to begin with? Sure, if you can afford the additional costs at every step you take, but this discussion is about cost to quality ratio. Want a digibeta to VHS or DVD window burn copy, that will cost at least double what a betacam sp to VHS or DVD window burn would cost. Want a back up source tape copy, more money on digibeta versus betacam sp. Want to go back into telecine for an additional one film reel make up shot transfer, much higher minimum cost to go to digibetacam than to betacam sp. Need to view your master tape for some reason, it's much easier to find a betacam sp machine than a digibetacam machine.

 

If you want to keep your workflow the least expensive, then keep it simple by using mini-dv and forget what everyone else says, if you like the way the image looks when you are all done, that is what matters the most.

 

Not sure what you're saying here. Why would the authors transcode the Betacam source tape to another format for evaluation? The Betacam signal was recorded on a Betacam VTR, played back on a Betacam VTR, and evaluated on standard terminal test gear. The DV signal was recorded on a DV VTR, played back on a DV VTR, and evaluated using standard terminal test gear. No transcoding.

 

Do you have a link to this particular study, maybe I confused it with another one.

[Graeme Nattress]

Here's links to tests I performed, with full details of what was done and why.

 

http://www.lafcpug.org/Tutorials/basic_chroma_sample.html

 

A pristine 35mm source was used, and a high quality Digibeta telecine of it was also used as source material.

 

You can clearly see that the DV copy is closer to the original than the BetaSP copy, especially in the luma, where SP is visibly blurred compared to the DV or Digibeta.

 

Graeme

[Alessandro Machi]

Here's links to tests I performed, with full details of what was done and why.

 

http://www.lafcpug.org/Tutorials/basic_chroma_sample.html

 

A pristine 35mm source was used, and a high quality Digibeta telecine of it was also used as source material.

 

You can clearly see that the DV copy is closer to the original than the BetaSP copy, especially in the luma, where SP is visibly blurred compared to the DV or Digibeta.

 

Graeme

 

But you never actually did Betacam sp component via a kona card or black magic card.

[Graeme Nattress]

Nope, we used the Digibeta's pass-through (no compression) YPbPr to SDI conversion.

 

Graeme

[Bernhard Zitz]

a little off topic question:

 

Does a DV-device (deck, camera etc.) smooth the chroma on the analog out (compenent, S-Video or composite)?

Edited April 1, 2007 by Bernhard Zitz

[Graeme Nattress]

Not off topic, really..... Yes, the outputs are smoothed, but they're ananlogue, and hence they degrade the picture a little too. That's why SDI works so well, or smoothing or fixing in software.

 

Graeme

[Walter Graff]

quote name='Graeme Nattress' date='Apr 1 2007, 09:44 AM' post='164117'] It amazes me to read such forum postings!

 

Graeme

 

Wow Graeme. Me too! I'll save this thread as an example of how people repost information they find on the web as first person and debate numbers with little experience in actual usage. It's the equivalent of having a bunch of baseball fans tell you statistic after statistic about Babe Ruth who will then get into a debate at how he was as a player, yet they never really saw him play. As much as I know this is common in most every thread these days, I still can?t believe how much folks who really have little experience in some topics still have to chime in as if they do.

 

My take on the answer based on extensive use of both is that both will give you good results. While the specs on DV are not technically as robust as Beta, it's the higher perceived luminance bandwidth of DV that makes up for any differences in perceived quality. Beta is more difficult to get into your NLE so if price is a factor, use DV. Outside of that, it would be difficult to tell the difference in the two side by side once all factors are taken into account.

[Alessandro Machi]

Nope, we used the Digibeta's pass-through (no compression) YPbPr to SDI conversion.

 

Graeme

 

and then you DOWNCONVERTED that to mini-dv, thereby nullifying your betacam sp evaluation.

[Sam Wells]

I don't get the point of this argument.

 

If it's Std Def, transfer to Digital Betacam like 98% of Planet Earth & go where you need from there.

 

If the project will never have a life beyond a DV codec & whatever is output from that, do DVCam.

 

If you want the highest quality, make a contact print :D

 

-Sam

 

Now let's argue MII vs 1" Type B :lol:

[Graeme Nattress]

and then you DOWNCONVERTED that to mini-dv, thereby nullifying your betacam sp evaluation.

 

NO!!!! Read the article again.

 

BetaSP was converter from YPbPr to SDI via DigiBeta and then brought in 10bit uncompressed 4:2:2 and 8bit uncompressed 4:2:2 via SDI.

 

Graeme

[Walter Graff]

NO!!!! Read the article again.

 

BetaSP was converter from YPbPr to SDI via DigiBeta and then brought in 10bit uncompressed 4:2:2 and 8bit uncompressed 4:2:2 via SDI.

 

Graeme

 

Graeme,

 

You are fighting a loosing battle...

[Bernhard Zitz]

NO!!!! Read the article again.

 

BetaSP was converter from YPbPr to SDI via DigiBeta and then brought in 10bit uncompressed 4:2:2 and 8bit uncompressed 4:2:2 via SDI.

 

Graeme

I think graemes goal was to get the BetaSP-Footage in the best possible quality into his computer, and that was by using a DigiBeta-Deck that also plays BetaSP, this way you get SDI-out from a BetaSP-tape...

 

by the way, thanks graemes for the link to this website, finally a comprehensiv comparsion between this formats...

Edited April 1, 2007 by Bernhard Zitz

[Graeme Nattress]

I think graemes goal was to get the BetaSP-Footage in the best possible quality into his computer, and that was by using a DigiBeta-Deck that also plays BetaSP, this way you get SDI-out from a BetaSP-tape...

 

by the way, thanks graemes for the link to this website, finally a comprehensiv comparsion between this formats...

 

 

Nope, it was played from a BetaSP deck, over component, to the Digibeta deck which did a passthrough YPbPr to SDI conversion, and out to the Mac capture card. And I didn't do it - a big post house in Toronto did it all for me as they were very interested in the results. I processed all the images and wrote up the results, and presented it to them all at a meeting of the Toronto FCP user group.

 

Yes Walter - loosing battle. Somedays it's not worth getting out of bed. Not to worry though, I've got much better stuff to be working on.

 

Graeme

[Alessandro Machi]

NO!!!! Read the article again.

 

BetaSP was converter from YPbPr to SDI via DigiBeta and then brought in 10bit uncompressed 4:2:2 and 8bit uncompressed 4:2:2 via SDI.

 

Graeme

 

Part of your test involved transfering Betacam Sp to DV-CAM. Using that data as a part of your tests confuses the overall comparisons that you are doing between DV and Betacam Sp. You state in your analysis....

 

...."the BetacamSP was brought in via a component dub to DVCAM, and from there via SDI and Firewire.".....

 

----------------------------------------------------

 

Rather than dubbing the Betacam SP signal to DV-CAM, a more useful test would have been doing a component dub from the betacam sp directly to a high quality transcoding card at the 10 bit, 8 bit, or DVC-Pro 50 codec.

 

----------------------------------------------------

 

One sentence prior to the above quote you state...

"The BetacamSP was brought in by multiple methods: buy using the Digital Betacam deck as a high quality component to SDI converter to allow the analogue video to be brought in via SDI uncompressed 4:2:2".....

 

-----------------------------------------------------

 

I think that this is a great way to proceed when making archival and video Duplication masters, however when doing very specific analytical tests as you have done, I would question whether the betacam sp to serial digital transcoding technology is the only method to test as the Sony Transcoder is approximately 10 years old and may have been designed by Sony to create the best looking video picture versus the highest resolution capacity. Did Sony design their analog to serial digital transcoder ten years ago to get an A plus for the particular tests you conducted, or did they design the betcam sp to serial digital transcoder to get the best possible looking picture, and was Sony limited in what they did because they did ten years ago?

 

Isn't it possible that the component out signal from either a Digi Beta deck or a betacam sp deck (but not the UVW decks) represent a truer, unretouched version of the Betacam SP signal? Afterall, we are talking about ten year old serial digital transcoding technology that you relied on. I'm not knocking the transcoder, it's excellent when looking at the results it produces, but that is a different application from what you were doing with it.

 

One missing test in your analysis would have been going directly from betcam sp component out to a Kona Card or similar high end transcoding card which would convert the component signal to a 10 bit or 8 bit uncompressed codec or even DVC-Pro 50 codec, this would have been a more useful study in my opinion than the portion of your tests in which you took the betcam sp signal and converted it to DV-CAM.

 

I'm not criticizing your results, just that your study lacks any native betacam sp component out directly to the newest transcoding options on the market. If you do ever do this test, please make sure the tracking knob on the betacam sp deck has been optimally set otherwise your results would be tainted.

[Graeme Nattress]

Of course, there's a good reason why we didn't do component straight into a capture card..... The cards available at the time were all SDI only. The budget for the experiments was already pretty high, so we could only do what we had the gear for or could borrow the gear for.

 

"The BetacamSP was brought in by multiple methods: buy using the Digital Betacam deck as a high quality component to SDI converter to allow the analogue video to be brought in via SDI uncompressed 4:2:2, and the BetacamSP was brought in via a component dub to DVCAM, and from there via SDI and Firewire."

 

It's a long article, lots of tests. I probably should have done 5 articles out of it instead of 1.

 

Graeme

[ryan_bennett]

I realize DVCAM is pretty close to Betacam SP so what do you guys think about transfering to DVCAM instead?

[Graeme Nattress]

DVCAM is identical in image quality to DV, and both are superior to BetaSP, not to mention cheaper and easier to get into your computer.

 

Graeme

[Alessandro Machi]

Nope, it was played from a BetaSP deck, over component, to the Digibeta deck which did a passthrough YPbPr to SDI conversion, and out to the Mac capture card. And I didn't do it - a big post house in Toronto did it all for me as they were very interested in the results. I processed all the images and wrote up the results, and presented it to them all at a meeting of the Toronto FCP user group....Graeme

 

You really should do a better pathway than that. Why not just use the digibeta deck and ONLY the digibeta deck? Answer, they probably didn't have the betcam sp playback card in it. So instead they used two video decks to get the betacam sp signal converted, that's not a fair evaluation.

 

Of course, there's a good reason why we didn't do component straight into a capture card..... The cards available at the time were all SDI only. The budget for the experiments was already pretty high, so we could only do what we had the gear for or could borrow the gear for...... Graeme

 

The Kona 2 card was released around January 7th of 2005, yet your study wasn't completed until well after that day, no? And if your going to slam a format like betacam sp, stating that "you could only do what was available to you" is not a good enough reason.

 

DVCAM is identical in image quality to DV, and both are superior to BetaSP, not to mention cheaper and easier to get into your computer....... Graeme

 

On your website you state that betcam sp's color is halfway BETWEEN digital betacam and dv-cam, yet somehow dv-cam overcomes this and is "superior" to betacam sp. I really wish you'd add what's missing to your study and evaluate betacam sp more fairly than you did. Betacam Sp has a separate luminence channel and a direct conversion from component to uncompressed 10 bit might have produced more quality than the methods you used in your evaluation.

[Graeme Nattress]

Because luma resolution is more important than chroma resolution. Without doing the extraction of the chroma and making it more visible, you couldn't eyeball a chroma difference between the three formats (when DV was correctly smoothed because of the way the codec works). However, the luma difference was instantly visible as a blurring of fine detail.

 

No matter what you do to it, you're not going to magically get more resolution out of it than 400 or so lines, whereas DV and DigiBeta will always be giving you the full 550 or so, and that difference is quite visible.

 

The full methodology used was given so you, if you want to, or have the time and money to spend doing so, can reproduce it - if you don't think that methodology was right, you have the option to perform and write up the experiment of your choice.

 

Graeme

[Alessandro Machi]

Because luma resolution is more important than chroma resolution. Without doing the extraction of the chroma and making it more visible, you couldn't eyeball a chroma difference between the three formats (when DV was correctly smoothed because of the way the codec works). However, the luma difference was instantly visible as a blurring of fine detail.

 

No matter what you do to it, you're not going to magically get more resolution out of it than 400 or so lines, whereas DV and DigiBeta will always be giving you the full 550 or so, and that difference is quite visible.

 

The full methodology used was given so you, if you want to, or have the time and money to spend doing so, can reproduce it - if you don't think that methodology was right, you have the option to perform and write up the experiment of your choice.

 

Graeme

 

 

Digital S, also known as D-9, is rated at the following...

 

VIDEO sampling: 4:2:2 8-bit component

Y: 13.5 MHz

R-Y/B-Y: 6.75 MHz

 

Notice the 13.5 MHZ for the luminence channel. Does anyone really believe that D-9 is "better" than digital betacam? You are placing far too much importance on the luminence channel.

 

Super- VHS was introduced back in the very late 80's as having more horizontal resolution than one-inch video, hahahahaha, yeah right.

 

3/4 video has LESS resolution than standard VHS, yet put them side by side and 3/4 video blows away VHS, fixating on one aspect of the video signal does not tell a complete story.

 

-------------------------------------------------------------------------------

 

The point here is that YOU have made claims above and beyond what YOU actually tested.

[Graeme Nattress]

You speak in riddles. 13.5Mhz is the luma bandwidth for all SD digital formats from DV to Digibeta. They all have identical luma resolution. That's your 4, in 4:2:2, the 2 being half of 13.5Mhz, or 6.75Mhz. DV halves the chroma bandwidth again, so it's 4:1:1. Properly smoothed, on a decent monitor, you won't really see that, but it does effect things when you start doing keys and other effects.

 

Luma bandwidth / resolution is one factor. There are others, like signal to noise ratio, and if you don't take that into account then yes, you'll get the nonsense that S-VHS looks better than 1".

 

Graeme

[Alessandro Machi]

.......DV halves the chroma bandwidth again, so it's 4:1:1. Properly smoothed, on a decent monitor, you won't really see that, but it does effect things when you start doing keys and other effects.

 

Luma bandwidth / resolution is one factor. There are others, like signal to noise ratio, and if you don't take that into account then yes, you'll get the nonsense that S-VHS looks better than 1".

 

Graeme

 

It sounds like you are saying that DV can be made to look good, but that beta SP somehow is just inferior, even though if you've looked at an actual betacam sp component feed on a component monitor it looks quite striking.

[Graeme Nattress]

If you play a DV deck out via component, you get the correct chroma smoothing that say, the apple codec does not, and you get a superb image that would be superior to that of the a BetaCamSP component feed to the same monitor. You will get a visibly sharper image, with lower noise.

 

Graeme