Thoughts on XDCam EX

[Thomas Smet]

Originally Posted by Kevin Shaw

But DVCAM is exactly the same as DV other than the process for recording the signal to tape, whereas XDCAM HD is in fact a higher quality recording format than HDV. Also note that the maximum bit rate of XDCAM HD is only slightly less than one of the more popular recording modes for DVCProHD, with greater spatial resolution and (arguably) a more efficient codec - so it's not easy to draw clear quality distinctions between formats in this context.

The important thing will be to see what kind of images the EX camera produces once it's shipping. If Sony gets things right it should easily be the highest overall quality HD camera for under $10K, and if you want something better than that you'll have to spend a lot more money.

Only for the 35mbit mode. The 25mbit mode is exactly the same as HDV. For the most part the formats are pretty much the same except for the 35 mbit mode can use more bits to help in complex situations. Remember the 35mbit mode is 35mbit max. The average is still around that of HDV. In terms of color space or resolution the 35mbit mode is exactly the same as 25mbit HDV. The only thing that gets better is the ability to compress the complex areas so there is less chance of macro blocking. Saying they are different is like saying a 8 mbit DVD is totally different then a 6 mbit DVD. I am of course only talking about the codec itself and not the media or camera head itself.

It's not that 35mbit mpeg2 is so much better it is more the fact that 25mbit HDV was always pretty darn good and 35mbit is just that tiny boost to cover the few areas where HDV may fall apart.

You also cannot compare 1280x720x24 DVCPROHD to 1440x1080x30 mpeg2. The bitrate for that format has nothing in common with mpeg2 compression.

I'm not even talking about quality but target markets.

[Thomas Smet]

Originally Posted by R Geoff Baker

Given that DVCam and DV are the same format, same compression, same chroma sampling, et cetera ... I just don't follow your little equivalence chart?

GB

Again my post had nothing at all to do with quality but the target market and how the SD and HD products sit in relation to each other. We were talking about how the price for XDCAMHD isn't that bad because it is what the mid level has been used to for years.

[Kevin Shaw]

Originally Posted by Thomas Smet

Again my post had nothing at all to do with quality but the target market and how the SD and HD products sit in relation to each other.

Fair enough, but in this case you can't just compare codecs: you'll have to compare the overall quality of the camera to other alternatives in the same price range. The EX will target the same market as the Panasonic HVX200 and will likely outperform it in some ways, while possibly falling short in others. This will be a good example of how specifications and numbers don't tell the whole story, especially when different cameras make different trade-offs to hold price down.

[Peter Jefferson]

Originally Posted by Brian Cassar

So do you reckon that one can use a +12db in HD and get a decent acceptable picture? In SD a +12db is the limit for event videos for an acceptable picture.Brian

With a sensor this size, and with the NR algorithms already seen in the likes of smaller imagers (as seen in V1 etc) the answer would be a tentative yes.

I feel that Sony have come a long way in this, low light performance was one the reasons the PD did so well.. then again, that was due to massive pixels and low res... but to be frank, the PD is what set the standard for this form factor camcorder

Originally Posted by Brian Cassar

Another point is that one should not talk about lux levels but rather sensitivity when one is considering minimum illumination. The F-330 is rated as f/9 at 2000lux whilst the DSR-300 series were rated as f/11 at 2000 lux. At the same time the F-330 is rated as minimum lux of 0.13 whilst the DSR-300 was rated as 0.5lux.

In real world scenarios, with digital gain and the differences between interlaced and Porgressive luminance sensitivity, lux ratings don't mean much. I don't think so anyway.

The REAL difference in run and gun situations is how much tweaking will u need to do, to dim your light to get clean subjects and recognizable backgrounds without it going ugly.

Tech spec don't mean anything in this regard when running lights or gain. In essence, the argument is void due to these factors (unless youre a purist who never uses gain at a wedding... yeah right.. lol)

Its like saying an f2.8 lens is better than an f4

Its all specification. Aside from DoF you can easily change your ISO and have the same sensitivity from the f4 as you would if that f4 was in fact 2.8. Its all about the settings.

IMO, lux ratings don't carry much weight when it coms to deciding on a camera, as more often than not, gain up is used to fill the background exposure issues (in dim light) and a on cam light is used to highlight the subject.

This can be considered akin to ISO settings on a DSLR... the higher u go, the grainier it gets, regardless...

Originally Posted by Brian Cassar

Unless Sony put in some real sensitivity in the EX, it would not be suitable for event videos where filming in very low light levels ids the norm.

Well, as far as the market need is concerned, SD low light performance has been acceptable for many MANY years. If it wasn't, the PD itself (and its competitive brethren) would not be so popular. In turn, going with imager spec alone, this would come VERY close to that sort of SD sensitivity (possibly between DV and HDV camcorders).

Your best bet would be to take an F330/350 out and judge the imager response to low light for yourself. This is purely imager testing, as by the time the EX is released, they'll probably improve on NR

[Thomas Smet]

Originally Posted by Kevin Shaw

Fair enough, but in this case you can't just compare codecs: you'll have to compare the overall quality of the camera to other alternatives in the same price range. The EX will target the same market as the Panasonic HVX200 and will likely outperform it in some ways, while possibly falling short in others. This will be a good example of how specifications and numbers don't tell the whole story, especially when different cameras make different trade-offs to hold price down.

Who is comparing codecs? My posts had nothing at all to do with codec quality. My comparison of XDCAMHD and HDV is pretty much like the comparison of DVCAM to DV. Yes they are pretty much the same but one is usually used on much better equipment so it tends to be in a higher market level. My whole point is that it isn't so much the codec that makes XDCAMHD better since the codec itself is for the most part the same as HDV but it is the equipment that goes along with that codec that make it better. The reason why XDCAMHD at 25mbits looks better then HDV at 25mbits is because XDCAMHD has much better encoder chips which cost a lot of money. I don't even want to talk about quality because that is the huge unknown right now. The EX could end up looking like garbage for all we know. I'm sure it will not look that bad but we have no way of knowing until it gets here.

[Greg Boston]

Originally Posted by Thomas Smet

The reason why XDCAMHD at 25mbits looks better then HDV at 25mbits is because XDCAMHD has much better encoder chips which cost a lot of money. I don't even want to talk about quality because that is the huge unknown right now. The EX could end up looking like garbage for all we know. I'm sure it will not look that bad but we have no way of knowing until it gets here.

Not just encoder chips, but the larger imagers. You're putting more latitude and lower inherent noise levels offered by larger sensors into the encoder. That allows the encoder to spend its bits on things that matter, rather than encoding noise. The XDCAM EX will offer this same capability and then some.

Much like the way a DSR570 can get such a nice picture on DVCAM even though it is the same compression and chroma subsampling as mini-DV.

As has been stated, specs alone can't be used to judge overall picture quality. There's a lot of magic behind the scenes with the advanced knowledge of MPEG2 compression going into these cameras.

-gb-

[Kevin Shaw]

Originally Posted by Thomas Smet

My comparison of XDCAMHD and HDV is pretty much like the comparison of DVCAM to DV. Yes they are pretty much the same but one is usually used on much better equipment so it tends to be in a higher market level.

Okay, that makes sense enough. Getting back to the issue of recording cost, the EX won't have a set cost in the sense of any tape-based format where you keep the tapes, so the cost will just be whatever you spend to archive the footage. With today's hard drive prices you could make archives of EX footage that way for about $3 per hour of video, or $6/hour with a duplicate backup. That's comparable to the cost of miniDV tape from a camera targeted at a higher level market, so that's quite reasonable.

As far as physical storage requirements are concerned, three 500 GB hard drives would hold over 90 hours of XDCAM HD footage - how much space would 90 hours of DVCAM or HDCAM tapes occupy?

[R Geoff Baker]

Given that the VX2100 is all but identical to the PD170, but that one is DV and the other DVCam, I'm not sure it gains any argumentative clarity to imply that one is 'usually better' than the other. If the comparison is between bits of hardware -- and the most usual test, price, is somehow lacking -- then leave out all mention of formats, me thinks.

Cheers,
GB

[Alex Leith]

I'd be interested to know who would rather record 25Mb/s over 35Mb/s...

I guess wedding and event videographers. But I presume most people would want to use 35Mb/s even at the expense of storage capacity.

And as for 18Mb/s... I wonder if that rate EVER gets used on the F330/350?

[Greg Boston]

Originally Posted by Alex Leith

I'd be interested to know who would rather record 25Mb/s over 35Mb/s...

I guess wedding and event videographers. But I presume most people would want to use 35Mb/s even at the expense of storage capacity.

And as for 18Mb/s... I wonder if that rate EVER gets used on the F330/350?

The original inclusion of 25mb CBR was to allow a semblance of compatibility with HDV from an NLE point of view. Although the audio is 4 channel uncompressed, unlike that of HDV. Most NLEs were already supporting HDV by the time of the camera's release last year.

The 18mb I learned, was for compatibility in ENG work. The newer digital satellite and microwave channel bandwidths are 18mbs. This way, the footage could be shot and fed without the need for a datarate down conversion which would be an additional MPEG compression cycle. It also gets you more recording time per disc.

-gb-

[Thomas Smet]

Originally Posted by Alex Leith

I'd be interested to know who would rather record 25Mb/s over 35Mb/s...

I guess wedding and event videographers. But I presume most people would want to use 35Mb/s even at the expense of storage capacity.

And as for 18Mb/s... I wonder if that rate EVER gets used on the F330/350?

It all depends on the type of event that is being shot. A long seminar type event where the camera is locked down and there is very little movement will look just as good with 18mbits/s as it would with 35mbits/s. In this case it would be an almost total waste to use the 35mbit mode because the video wouldn't look any better but you would have to keep changing disks all the time and you would run the risk of missing out on a minute or two of the event while you switched disks. With the EX this isn't really a problem since it has two card slots. You could keep swapping cards and downloading them without ever missing anything.

It pretty much comes down to longer recording times for those who need longer non stop recording times.

[Tom Roper]

Great topic guys.