Questions about the HMC150

I love my HMC151, really light and not as bulky as my HVX200... If you don't want to use tapes and so on, HMC151 could be a good camera to go with...

A lot of people are complaining with the AVCHD format being to heavy for most computers out there. I myself convert the files to DVCPROHD, and it works like a charm every time!

Does anyone by the way know if you lose any image quality by converting it to DVCPROHD?
 
It seems to me that yes, you loose image quality by converting to DVCProHD. When I compare frames of the different codecs the AVCHD always looks sharper to me. DVCProHD also has about 23% less pixels (the difference between 1280 square vs 960 rectangular pixels). I asked a Panasonic rep about this and he said he had no idea, and just to try shooting in 1080 instead.

But given that the entire news industry uses P2 cameras which mostly record in DVCProHD, I don't understand why I'm the only one bothered with this apparent quality loss.
 
TigerFX said:
But given that the entire news industry uses P2 cameras which mostly record in DVCProHD, I don't understand why I'm the only one bothered with this apparent quality loss.
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Simple... most of them shoot in SD/DVCPro25.

In my market, there are four news stations. Mine shoots P2. Even though we're broadcasting 1080i, and our studio is using 1080i cameras, and the control room is doing everything 1080i, and the graphics are 1080i, the photogs out in the field (except for some special pieces) are shooting in DVCPro25. Most of the workstations in the newsroom for the Avid system aren't fast enough to handle the bitrate of DVCPro 1080i, and the cost of upgrading would be in the seven figure range I was told.

And for comparison, of the other three stations... on is shooting on EX3's (a friend there I think told me 720p60), the other two are still shooting on Betacam SX (and Seattle is the #14 market in the country out of 230+). So it's not like we're getting beat in image quality. And honestly, if the photog knows what he's doing, some of the upscaled DVCPro25 still looks pretty darn good.

Plus, once you figure that only about 25% of the TV in the US are actually HD, and the fact that most of that HD is via cable or satellite (which compresses the crap out of their signals), we're not really loosing that much, even if the field photogs shot DVCProHD 1080i.
 
In my case I really must decode to DVCPROHD because of my computer and premiere crashing when I try to even nudge the marker on the timeline.. So to hear that it gives you less quality isn't that fun for me

Now, I have a lot to learn about all the technical stuff around codecs and such, but couldnt you go around this issue with decoding by importing the files in another SD format like DVCPRO50, edit it, and then export to any HD format that you may need it in... Wouldnt that work?

How come that the HMC, that's more or less a little brother to the hvx, is heavier for the computer to edit. My HVX fotage is really easy and painless to edit while the little brothers' avchd is a total killer for the computer?
 
Admir said:
In my case I really must decode to DVCPROHD because of my computer and premiere crashing when I try to even nudge the marker on the timeline.. So to hear that it gives you less quality isn't that fun for me
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Define "quality". Yes, you lose some resolution, but resolution isn't the endall to be all of "quality". Planet Earth for Discovery HD was shot mostly in DVCProHD, and I've never heard anyone complain about the quality of it :) . However, I don't think that the DVCProHD converter, while not bad, is that great at going from one format to the other (just what my eyes see on the computer screen). But the key is "not bad". What is your final destination? Web? TV? DVD? SD or HD? It may be "good enough" to get your job done.

Now, I have a lot to learn about all the technical stuff around codecs and such, but couldnt you go around this issue with decoding by importing the files in another SD format like DVCPRO50, edit it, and then export to any HD format that you may need it in... Wouldnt that work?
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Do you mean do the rough edit in SD, than replace all the footage with HD versions? Yes, people have been doing that in one form or another for years.

Another alternative is to use Avid's DNxHD format (which is free and works with Premiere), or spend $130 and get Cineform NeoScene and transcode everything into that format which edits pretty well in Premiere (I use NeoHD and have been pretty happy with it).

How come that the HMC, that's more or less a little brother to the hvx, is heavier for the computer to edit. My HVX fotage is really easy and painless to edit while the little brothers' avchd is a total killer for the computer?
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Because you're making a trade off. In order to get the tiny filesizes of AVCHD, you have to lose something. In this case, it's the fact that it's highly compressed and long-GoP. The way a long GoP format works is (and hopefully Barry Green or someone else can hop in and give a better explanation), you record a group of frames ("Group of Pictures") instead of individual frames. Basically, the camera only records the first frame, and then in the case of the HMC only records the pixels that change for the next fourteen (a fifteen frame GoP). The computer then goes back to the first frame for the pixel information that hasn't changed. This makes for very efficient file sizes, but it taxes the CPU of your computer a lot more because it has to work so much harder to decode each frame. With DVCProHD, each frame is it's own seperate frame... which is easier on your CPU, but requires more hard drive space for all the extra information.

Plus, Premiere CS4 pretty much sucks at decoding AVCHD (CS5 is sooooo much better).
 
Does that mean that the neoHD or dnxHD format actually gives you better resolution than the DVCPROHD format when transcoding from avchd?
 
Cineform and DNxHD will do full 1920x1080 and 1280x720. Cineform includes a program with all versions of Neo to do the conversion. You'll need to use Premiere or Adobe Media Encoder to convert DNxHD... which I know you said gave you grief, but hey it's free so no harm in trying.

Cineform

Avid's DNxHD download page
 
Install the free DNxHD codec from the link above.

There are a multitude of transcoding programs. Some free.

TMPEG ENC works great. There is a free and a paid version and I can't remember what the free version can not do compared to the paid version.

Actually here is a comparison spec sheet: http://tmpgenc.pegasys-inc.com/en/product/tp.html#tabSelector1

Free version download
http://www.tmpgenc.net/en/download.html

AS I said, there are some are completely free programs out there. Some are a pain to use though.

What are you using to edit? Most NLE's will handle DNxHD if the codec is installed.
 
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