ALL: New ac130/160 vs used hpx170?

Depends on which codec you're talking about. HDV was very prone to it. XDCAM-EX is a lot more robust, and AVCHD is even more robust. I've only seen AVCHD pushed to its limits when shooting an overwhelming amount of changing detail, such as a daylit forest with a splashing creek running through it, with rippling water all around, and the shot handheld. In that scenario yes the codec will break down and get a little blocky.

Short of that, AVCHD is pretty much reliable under most any scenario.
 
Barry, thanks for the clarifications. Since I use both codecs, I have seen AVCHD break down a couple times, and the example you used, flowing water was one of them. In this case, I equated motion to the breakdown, but how you described it, too much info, would be a much better description.

Mileage may vary, but for me, shooting I-frame increases my confidence under more difficult circumstances.

Grant
 
Mine too. There are many reasons why intraframe is used in all top-end codecs like avc-Intra, hdcam and hdcam sr, dvcpro-hd, prores, DNxHD, cineform, redcode, and on and on.

But all of those are relatively high bandwidth, from 100 to 440mbps. If you want high quality at lower bitrates, long-GoP can be an effective tool to make that happen, as long as it isn't overused or pushed too hard.
 
Going back the query the OP made, it seems that when folks are comparing the P2 cams (I-frame) to SD cams (AVCHD) that there is always the cost comparison of the memory as a prime consideration. No doubt, P2 is more expensive. IMHO, much of the value delivered by the P2 cams is in the codec.

Grant
 
Yes. That's why a really sweet deal on an HPX would allow me to get 2 hours worth of media and still be at less than an ac130. I said a sweet deal. Like, maybe unrealistically so.

Anyway, I'm running out of questions. When we're talking about the AVCHD codec falling apart, is this something you can see happening as you're shooting it/upon playback from the cam, or is it only evident when the necessary transcoding/etc. is done to make it usable in an NLE? Would you be able to see the problem in the field and at least attempt a correction (if it were feasible) or will you not know 'til it's too late?
 
Josh Bass said:
When we're talking about the AVCHD codec falling apart, is this something you can see happening as you're shooting it/upon playback from the cam, or is it only evident when the necessary transcoding/etc. is done to make it usable in an NLE? Would you be able to see the problem in the field and at least attempt a correction (if it were feasible) or will you not know 'til it's too late?
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It can't be seen while recording, only on playback. I'm not sure it would even be that easy to see on the small LCD.
 
Most NLE nowadays will let you edit the AVCHD natively. So long as you have a decently powerful system, there's no reason to transcode. There are lots of folks who recommend transcoding for quality purposes, but most tests will show that there is nothing gained (except slightly more fluid playback). In all situations, you're better off working with the native video all the way through post.
 
Josh Bass said:
When we're talking about the AVCHD codec falling apart
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Well, let's also specify what we mean by "falling apart" -- is it something you'll see AT ALL? Probably not. I mean, when HDV took a dump, it was awful -- it looked like an old internet video that got congested, you'd see big blocky blocks for half a second. When AVCHD gets overloaded, it doesn't get blocky, it gets a little softer. You might be able to detect some block edges if you super-hyper-pixel-peep on a still frame, but in general, in motion, it's pretty minor. The AVCHD codec is really quite robust and holds up surprisingly well in most every scenario.

I'm a major proponent of reliability (which is why even today I still prefer intraframe P2 over long-GoP AVCHD) but AVCHD has advanced the state of long-GoP to the point where I'm comfortable using it. It's not a problem, and even when you "break" it, it still looks pretty good, so don't stress too much about it.
 
The LCD on the HPX250 is at least 1,000,000,000,000,000,000 times better. It's 4x sharper, and it has an infinitely wider acceptable angle of view (i.e., rotating the HVX LCD off-axis made the picture turn to mush at very minor angles, but the AC130/AC160/HPX250 LCD can be rotated quite a ways and still holds up
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WOW!, yeah I just attended a panasonic product show in Tampa. They had the 130, 160 and the af100. As a long term user/owner of an HVX200 I was blown away by the LCD. Who needs focus assist now?? I could easily focus with these cameras just using the lcd screen in normal mode.!
BTW, the 130/160 cameras are HUGE. (Which I do like). I'm still amazed at how light weight they are compared to their size.
 
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