Review of HPX2700 Varicam

[David Heath]

Originally Posted by Seth Melnick

that is true about the sensor. But rez is much more then just the pixel sites on the chip - to really make a comparison MTF tests would have to be done on both cameras to compare what they actually record.

Well, rez doesn't directly equate to picture quality, true, but you can make pretty good predictions about rez from pixel sites, assuming the lens is not the limiting factor. Look at http://www.dvinfo.net/conf/panasonic...-3700-a-4.html for talk about the 2100, especially posts 53-57.

The danger with MTF tests is that if done simply as H & V wedges, it can be very difficult to distinguish between true resolution and aliasing. The answer lies in zone plates, and in that other thread, I linked to a BBC R&D review of the 2100 - http://www.bbc.co.uk/rd/pubs/whp/whp...ic-HPX2100.pdf . In that case, the 2100 front end is easily seen to produce bad aliasing (the "ghost" circles not centred on the bottom/left corner), which leads the reviewer to conclude that :

The resulting performance is a little disappointing. It is also evident that there is no optical spatial filtering in this camera, to suppress frequencies higher than can be resolved.

Simple 2 axis MTF tests would probably make one think that the mtf extended quite high. In practice, it's the aliasing that causes the effect. Beware.

But the 2700 is full rastor 1080 in the Image processing and output section.

I don't think so. I think you'll find that all image processing happens at 1280x720, with final output either unchanged as 720p, or converted up to enable a 1080 raster to be recorded. It's also worth noting that it doesn't employ any pixel shifting, that's obvious from the zone plate tests.

None of this is to say it won't produce a good picture, but it is wrong to describe it as "a true 1080" camera. The 3000 series is, the 2000 series isn't.

[Jeff Regan]

I have an HDX900 and find that an HPX500 looks very close in most ways, including resolution. I was surprised that the 500 did well in noise, the low end Canon HD lens had less chromatic aberration than my $19K Fujinon HA18X7.6 HD lens due to CAC. Obviously, the 900 offers more handles for setup, but lacks a lot of the 500 features--no SD, no variable frame rate except time lapse.

In my opinion the 2700, if recording in DVCPRO HD, doesn't offer that much more than a 500, except ramping of frame rates and native 720 imagers(which didn't offer the apparent advantage I expected). $13K more for a 2700 seems like a steep price over an HPX2000 or
HDX900 to me. Of course, compared to the original Varicam price, it's not so bad.

Regarding audio inputs, the front input is stereo, so that's two channels, the rear is left right as well, so four inputs, just like the 900 or 2000 or 3000. The LCD display isn't that important to me, the CRT viewfinder is so much better than an HPX500 viewfinder and the LCD is just too small for critical judgements, IMO. I always use a TV Logic 7" HD LCD on my 900.

Regarding lenses, all Fujinon HD lenses have CAC these days. I'm not convinced of HD lenses being superior to the best SD series lenses. I do believe that CAC is a great circuit.

Jeff Regan
Shooting Star Video

[Michael Kraus]

Ha, I absolutely flipped when I saw the list price of $39950.00 because my wishful thinking tricked my mind into seeing $3995.00

Ah well....back to the real world...

[Steve Phillipps]

Jeff, I think you'll find that the pictures from the HPX500 and HPX2700 are on different planets, let alone in different leagues. The 2700 has about twice the resolution, plus much better processing and codec. I'm pretty sure you'll see quite a difference even on a small monitor.
Steve

[Jeff Regan]

Originally Posted by Steve Phillipps

Jeff, I think you'll find that the pictures from the HPX500 and HPX2700 are on different planets, let alone in different leagues. The 2700 has about twice the resolution, plus much better processing and codec. I'm pretty sure you'll see quite a difference even on a small monitor.
Steve

Steve,

That would be great, but my HDX900 has native 720p imagers--are the 2700 CCD's different and if so in what way? My HDX900 has 14 bit processing like the 2700. So, other than variable frame rate ramping, that seems to leave AVC Intra. You can do AVC Intra with an HPX2000 for a lot less money.

I just don't see how a 2700, if comparing DVCPRO HD, could look like it's from a different planet compared to an HPX500. I had to strain to see differences between my HDX900 and an HPX500.

Jeff Regan
www.ssv.com

[Seth Melnick]

I can say from this test - that although the 500 creates amazing images - the 2700 is worlds apart from it. Would the casual user notice - perhaps just a bit - but the latitude and most important the graduations to highlights were far siginificantly better

[Steve Phillipps]

Jeff, in my limited knowledge of the engineering side of things! The AVC Intra 100 is a 10 bit codec whereas DVCPro HD is 8 bit, and it also allows full raster 1280x720 as opposed to pixel shifting employed in the HDX900 (which is 960x720 shifted up to 1280x720 I think!), and from what I've heard, the combination of these two things makes a pretty big difference. But I was really referring to the 2700 vs 500, and I have to disagree with you there as my look at the 720 images from the HPX500 showed it to be pretty soft, a long way off the original Varicam which I am familiar with, let alone the new 2700. Just my opinion though. On paper the 500 is terrific, but there's a reason why it's not been used on high end doc work much (at all?) and it's because the images are just not up to scratch - but good enough for news, corporate etc.
Steve

[Jeff Regan]

Originally Posted by Seth Melnick

I can say from this test - that although the 500 creates amazing images - the 2700 is worlds apart from it. Would the casual user notice - perhaps just a bit - but the latitude and most important the graduations to highlights were far siginificantly better

Seth,

Are you talkng DVCPRO HD to DVCPRO HD? I agree that a 10 bit AVC Intra codec is going to
have smoother gradiations than 8 bit AVC Intra. If AVC Intra is the difference, why not save
a bunch of money and buy and HPX2000? Or a demo or B-Stock HPX3000 for less than the
cost of a 2700?

Jeff Regan
Shooting Star Video

[Jeff Regan]

Originally Posted by Steve Phillipps

Jeff, in my limited knowledge of the engineering side of things! The AVC Intra 100 is a 10 bit codec whereas DVCPro HD is 8 bit, and it also allows full raster 1280x720 as opposed to pixel shifting employed in the HDX900 (which is 960x720 shifted up to 1280x720 I think!), and from what I've heard, the combination of these two things makes a pretty big difference. But I was really referring to the 2700 vs 500, and I have to disagree with you there as my look at the 720 images from the HPX500 showed it to be pretty soft, a long way off the original Varicam which I am familiar with, let alone the new 2700.
Steve

Steve,

The HDX900 uses native 720X1280 imagers, the exact same as the Varicam 27H series. There is no pixel shifting for 720p on an HDX900.

So, that seems to leave AVC Intra as the difference, because as much as I wanted to see
an easily discernible resolution difference between an HPX500 and my HDX900, I couldn't.
Nor signal to noise difference. I do think the 900 has more latitude, especially with DRS.

Again, I think the premium being charged for ramping frame rates over an HPX2000 with AVC Intra board is hard to justify. I could pickup an HPX3000 demo unit for $35,000 USD,
which really makes use of the AVC Intra codec by providing full raster recording or pay in
the low $20K range for an HPX2000 and add the AVC Intra board at any time.

Jeff Regan
Shooting Star Video

[Steve Phillipps]

AFAIK DVCPro HD in HDX900 is 960x720 and uses horizontal pixel offset to get to 1280x720.
Steve

[Jeff Regan]

Originally Posted by Steve Phillipps

AFAIK DVCPro HD in HDX900 is 960x720 and uses horizontal pixel offset to get to 1280x720.
Steve

Steve,

DVCPRO HD 720p is 720X960 with ALL Panasonic DVCPRO HD cameras, once recorded, including the HPX2700 and even HPX3000/3700.

So, let's not confuse what the HDX900 records(like all DVCPRO HD cameras) vs. what is available via HD SDI--a native 720X1280 image, no pixel shifting, no uprezzing/scaling for
720p with an HDX900, same as the HPX2000 and 2700.

In order to record 720X1280 with the 2000 or 2700 or 3000 or 3700 in 720p, that would require AVC Intra. AVC Intra also offers an additional stop of latitude. AVC Intra is a great codec, but you can get the benefits from a much less expensive HPX2000.

[Steve Phillipps]

Yeah, that's what I said, DVCPro HD does not give full 1280x720, but AVC Intra does.
Strangely enough, the same thought about the 2000 (actually 2100 here in the UK) crossed my mind, why not get that and add the AVC board for a lot less cash, but in actual fact the difference was quite small (maybe £2-3000). Also the BBC tests of the 2100 didn't go down too well, and it doesn't seem to be regarded as well as the original Varicam let alone the new one. I assumed that it had the same chip as the 2700 but it seems probably not.
Steve

[David Heath]

Amongst all this talk of resolutions, the biggest surprise to me was finding that the 2100 doesn't seem to have any optical low-pass filter, which I find amazing in a camera at this price point. The big question must be whether such has been included in the 2700.

At least with resolution you know what you're getting from the start. With aliasing, the pictures can look fine most of the way through the post chain, but the aliases mess up the compression system at the end or lead to broadcasters having to use higher than otherwise necessary bitrates.

[Jeff Regan]

Originally Posted by Steve Phillipps

Strangely enough, the same thought about the 2000 (actually 2100 here in the UK) crossed my mind, why not get that and add the AVC board for a lot less cash, but in actual fact the difference was quite small (maybe £2-3000). Also the BBC tests of the 2100 didn't go down too well, and it doesn't seem to be regarded as well as the original Varicam let alone the new one. I assumed that it had the same chip as the 2700 but it seems probably not.
Steve

In the US, an HPX2000 lists for around $25K for the body. At one point the AVC Intra board, a $3K option, was being included in the price. Even at $28K, the 2000 is still over $10K less than a 2700.

If the BBC didn't like the 2100, I assume this means they didn't like the HDX900 either? They have the same image in DVCPRO HD. The 2000/2100/900 use the same imagers as the Varicam 27H, a cleaner chipset than earlier Varicams and feature 14 bit processing vs.
12 bit for Varicam. While the Varicam 27 had Film Rec and a few other handles that the 900/2000/2100 don't have, that doesn't mean the latter cameras have an inferior image.

I am not aware of the 2700 having a different chip set, but perhaps it does. Regardless,
it would be the same resolution, otherwise it would compete with the 3000/3700.

So, I am still left with the question, what besides AVC Intra would lead one to believe that the 2700 is so superior to a 500 or 900 or 2000/2100--why is it worth a $13K + premium
over a 900 or 2000/2100, which all have native 720p sensors?

Jeff Regan
Shooting Star Video

[Steve Phillipps]

According to the technical guru at the BBC the Varicam, 900 and 2100 all have different images, with the Varicam top of the heap.
The latest price for an HPX2100 I had in the UK was around £21000!
Steve