New Canon XA25, XA20 and HF G30 camcorders

[Jack Zhang]

Originally Posted by Buba Kastorski

oh yes, can't wait,
now, if we can also have 50Mbps 1080/60p PMW camera this year,
please?

Most likely a XAVC 1080p60 cam recording at 200Mbps would be the update to the PMW lineup.

[Kyle Root]

I was just browing the specs, and it looks like maybe they've dropped internal flash memory on these new ones?

The XA10 had 64GB internal...

[Glen Vandermolen]

Originally Posted by Kyle Root

I was just browing the specs, and it looks like maybe they've dropped internal flash memory on these new ones?

The XA10 had 64GB internal...

Yes, they did.

[Kris Zimbelman]

XF 100 has 50Mbps MPEG-2 Recording 4:2:2 Color Sampling for 2,499 and more professional looking.
I wonder if the XA 25 will have better low light?

[Steve Struthers]

It's interesting to see that the price of the XF100 has dropped substantially. That leads me to suspect that Canon might be bringing out an XF100 replacement. Or possibly they're going to ditch the XF100 instead, and let the XA25 take its place, with the XF300 serving as a demarcation point between their 4:2:0 prosumer cams and their 4:2:2 capable line.

I can see a lot of buyers opting for the XA25 over the XF100 just to get the longer lens and other goodies the XA25 offers, even at the cost of having to sacrifice the 50 MB/s output the XF100 is capable of.

As good as the X100 and its bigger sibling, the XF300 are, they both seem to be at the point where a refresh and even a redesign might be order.

[Steve Struthers]

Originally Posted by Kyle Root

I was just browing the specs, and it looks like maybe they've dropped internal flash memory on these new ones?

The XA10 had 64GB internal...

It does look like the internal memory has been dropped. I checked out the B&H website for their listings of the XA25/20 cams and found notes indicating that external memory is required for both.

[David Heath]

Originally Posted by Jack Zhang

Most likely a XAVC 1080p60 cam recording at 200Mbps would be the update to the PMW lineup.

Interesting thought....... But it's worth bearing in mind that the higher the frame rate, the more the efficiency advantage to long-GOP recording.

The logic is that if you keep the I frames at the same time interval (1/2 second, say) you get about twice as many difference frames if you double the frame rate. Since the I frames are much larger than difference frames, it follows that doubling the frame rate doesn't mean doubling the bitrate for comparable quality. That's why for 30fps AVC-HD has a bitrate of 24Mbs, and 60fps is 28Mbs.

For top end gear (F5/55) then yes, expect I-frame only XAVC. But at the lower end, PMW200 etc, I'd say long-GOP XAVC is far more likely for reasons of economy, and quite likely around the 50Mbs mark.

Just don't underestimate the computing power needed to deal with such. I do think it will come - but unless you really need 50/60p there's a lot to be said in terms of ease of handling in staying with XDCAM 422 and 50 Mbs, as no broadcasters are transmitting such. (And are unlikely to ever do so IMO - 50/60p isn't in current transmissions specs, and any next gen broadcast system is likely to leapfrog 1080p/50 straight to 4k.)

[Jack Zhang]

28mbps AVCHD 2.0 IMHO is not broadcast compliant at all. The example I saw with waves breaking on a shore in the Caribbean was absolutely horrible in terms of macroblocking. I agree that the GH3 hit the sweet spot in terms of 1080p60 and Long-GOP. There is totally room for that spec in XAVC, with 10-bit and 4:2:2 as extra included. My opinion involves 100Mbps Long-GOP rather than 50, that would be more broadcast compliant and hence more EBU/BBC compliant.

[David Heath]

Originally Posted by Jack Zhang

28mbps AVCHD 2.0 IMHO is not broadcast compliant at all. The example I saw with waves breaking on a shore in the Caribbean was absolutely horrible in terms of macroblocking.

Sorry - I didn't mean to imply I considered 28Mbs AVC-HD broadcast compliant (nor 24Mbs AVC-HD for standard frame rates, for that matter :-) ) - I mentioned the 24/28Mbs versions to demonstrate that doubling the framerate does not mean you have to double the bitrate in a long-GOP system.

(And also worth saying that especially with AVC based systems, all coders are far from equal, especially real time ones. For a given image and a given bitrate, one coder might do a good job, another give poor results. That's especially true in cheaper consumer grade cameras - where you're currently more likely to get 28Mbs AVC-HD.)

And yes, it's quite clear that XAVC has long-GOP (with 10 bit, 4:2:2 and 50p) within the spec as well as the I-frame only version. I'll keep an open mind over bitrate, but as long-GOP is supposed to give an efficiency advantage of about 2-3x over comparable I-frame only at "normal" frame rates, I'd say it's reasonable to expect something like 4x at double frame rates. I agree with the 200Mbs for I-frame and a quarter of that is how I got to (guess at) 50Mbs as a sensible figure for comparable long-GOP.

But yes, it's speculation - we'll see.

[Kris Zimbelman]

Originally Posted by Jack Zhang

28mbps AVCHD 2.0 IMHO is not broadcast compliant at all. The example I saw with waves breaking on a shore in the Caribbean was absolutely horrible in terms of macroblocking. I agree that the GH3 hit the sweet spot in terms of 1080p60 and Long-GOP. There is totally room for that spec in XAVC, with 10-bit and 4:2:2 as extra included. My opinion involves 100Mbps Long-GOP rather than 50, that would be more broadcast compliant and hence more EBU/BBC compliant.

What is the lowest level (Least expensive) of compression necessary to avoid the macro blocking you mentioned above? JVC 600 series do it?

[Jack Zhang]

The Blackmagic Hyperdeck would get you ProRes HQ, which is 220Mbps. This is not camera dependent as this is an external recorder. Ideally, pick a camera for the best uncompresed picture, then choose an external recorder.

50Mbps MOV would be a nice addition to the XA25, which would give more incentive for that cam with it's HD-SDI port.

[Thomas Smet]

Honestly 50mbits mpeg2 can macro block a lot as well. In fact with a good encoder AVCHD at 28mbits can look just as good as 50mbits outside of the 4:2:2 color of course. I consider 50mbits with mpeg2 to be the minimum for decent quality but it by no means is a great quality format. Plus remember mpeg2 can only use blocks that are 8x8 pixels so if it does macro lock you may notice it more with the naked eye.

Honestly for keying I have had much better results from 4:2:0 AVCHD than I have had from 4:2:2 mpeg2 due to the smaller AVCHD block sizes during sudden movement. If nothing moves the mpeg2 looked great but for action shots against greenscreen the mpeg2 would fall apart in the heavy motion blur areas much quicker.

Then again I was using a GH2 hacked to 100mbits so it may be a slightly unfair comparison.

[Don Palomaki]

My take is that the XA-series target buyer is the moderate budget event videographer (think weddings and Bar/Bat Mitzvahs) and higher end home user who wants good toys for their daughter's soccer games and son's birthday parties. If it looks good on their home theater projection system (or 60"'+ flat screen) and better then their neighbors handi-cam, they are very very happy. That community is not all that concerned about 4:2:0 vs. 4:2:2 or 8-bit vs. 10-bit or SDI. On the other hand, an easy way to dump to DVD or Blu-Ray is important.

[David Heath]

Originally Posted by Thomas Smet

Then again I was using a GH2 hacked to 100mbits so it may be a slightly unfair comparison.

In which case it wasn't AVC-HD...... The latter defines a sub-set of H264, the top level of which is 24/28Mbs.

If it's 100Mbs, it's not AVC-HD, by definition.

[Steve Struthers]

Originally Posted by Don Palomaki

My take is that the XA-series target buyer is the moderate budget event videographer (think weddings and Bar/Bat Mitzvahs) and higher end home user who wants good toys for their daughter's soccer games and son's birthday parties. If it looks good on their home theater projection system (or 60"'+ flat screen) and better then their neighbors handi-cam, they are very very happy. That community is not all that concerned about 4:2:0 vs. 4:2:2 or 8-bit vs. 10-bit or SDI. On the other hand, an easy way to dump to DVD or Blu-Ray is important.

I think you've pretty much nailed the target market. But don't forget the documentary and corporate users whose main content distribution conduits will be streaming video sites like Youtube and Vimeo, (plus their own websites), who happen to have very small budgets for video production. These users will also want the best possible image quality they can get for their limited budgets, and cameras like the XA20/25 will fill that bill quite nicely. For such users, it isn't necessary that the cameras are capable of recording with a broadcast-compliant codec.