Sony HDR-CX100, AVCHD and FCP?

[Adam Schoales]

whoops! meant MiniDV NOT miniDVD. i hate those things haha

[Caspian Brand]

Hi Adam,

I’ve recently been able to try first hand the AVCHD / FCP workflow with these new flash memory based camcorders. I do have to say that I far prefer it to the tape based workflow of MiniDV. However, there are some compromises and adjustments that need to be made.

First of all, what I like about MiniDV:
-Relatively inexpensive media, at a 25Mbps Data Rate
-Media is logged and “captured” at this same data rate, and you have a physical, logged copy for backup
-16:9 aspect is supported for the “feel” of HD vs. the 4:3 of SD.
-It is a widely supported coded and is very CPU/storage efficient

What I don’t like about MiniDV:
-It requires the camera to have physical moving parts, which need to be maintained at a greater expense. For example, when I last had to have my MiniDVs camera’s heads professionally cleaned, it cost ~$250 (though there are steps one can take to minimize the frequency of head cleanings such as always using the same manufacturer/grade of tape, and making sure to use a tape based head cleaner between each time you may have to use an alternate tape stock).
-As you pointed out, MiniDV is on it’s way out the door, even in the Standard Def camcorder world.
-DV25 is a relatively old codec by comparison to AVCHD, and uses only a 4:1:1 color sampling ratio.

What I like about AVCHD:
-It’s a new codec developed by Panasonic, which is being widely accepted as a new standard.
-It uses a 4:2:0 color sampling ratio
-It supports a wider variety of compression ratios to lessen the amount of storage needed for the original material.
-Cameras supporting this codec do not require moving parts, when using only flash based media.

What I don’t like about AVCHD:
-Log and Transfer seems to take about as long as “Log and Capture” from tape.
-The codec efficiency/size is thrown out the window as soon you Log and Transfer into FCP, as the AVCHD media is upconverted to either PRORES 422 or Apple Intermediate (which some say is a faster conversion than to PRORES) yet both take up the same amount of space, which is at least 4x more space than the footage in it’s native compression, and sometimes more (depending on your camera settings).
-PRORES and Apple Intermediate take less strain on your CPU and RAM when editing, but require at least 100 Mbps of throughput, and the upconvert process doesn’t “add” image quality, just bloated space so your CPU and RAM can work more efficiently when editing.
-The purported equivalent media cost is not the same when you compare data rates of DV25 to HD sizes of AVCHD. An 8GB SD Card or MemoryStick is $35 on sale, and will only store about 40 min @ 24 Mbps (if your camera supports that data rate, I think most Sony camcorders cap out at 16Mbps). A 3 pack of DV25 tapes @ 3 hours in 25Mbps costs $30. So you can see it is nearly 3x more expensive to keep your footage archived on the flash media at a similar data rate, which drives people to offload their original media to more volatile spinning discs, and increase the amount of time spent archiving un-edited content.

While a lot of this is a nitpicky numbers comparison, Storage is larger and cheaper today than ever, and it’s not very difficult or expensive to keep your data migrating every couple of years to newer, larger, spinning disks. Flash memory prices are coming down too, and I haven’t spent enough time with the new codecs to determine if their lower bitrate modes of say 9Mbps in an HD frame size are comparable in visual quality to a 16:9 SD frame size at 25Mpbs. One might assume by the greater number of vertical lines of resolution that this would be so, no matter the data rate, but I’ve seen some HD upconverts of 16:9 SD material that looked pretty darn good. Remember also the color space of AVCHD is a far cry better than DV, which is probably most important in overall perceived image qualtiy.

I like not having the fragile moving parts that have to be expensively maintained and worn out in the camcorder, or having to use it as a playback deck too, further shortening it’s life.

Hopefully the addition of new PRORES bitrates in FCP 7 will allow “Log and Transfer” to PRORES Proxy, which is only 45 Mbps, and wouldn’t require as much bloated space as PRORES 422 or Apple Intermediate (which is equivalent to DVCPRO HD in Data Rate).

As a videographer, my only complaint about the lower end Sony’s is the lack of Manual Focus, and the flimsy touch screen menu interface. I prefer the Canon function select button on this grade of camera. Ultimately, depending on the type/creativity of the work you do, a nicer Sony, Canon, or Panasonic camera in the Prosumer range that has a multi-function dial or Manual Focus ring might be better.

Hopefully my opinions here help.

-=C=-

[Adam Schoales]

Hi Caspian!

Thanks so much for your response. It’s really great to have a response from someone who has actually USED the devices I’m working with and can give pros and cons than someone who just says “HD is better. duh!”.

I shot this dance show on the weekend and was surprised by how smoothly things went. The lowlight wasn’t TOO much of an issue (and I presume any noise i see will be heavily reduced when we go back down to SD for the DVD). The storage space is a bit of a pain, especially when you consider that 8gb is going to be even BIGGER once I bring it into final cut, but since, again, im going down to SD in the end anyways i’ll likely convert those pro-res to DV and just work from those. I was only shooting in HD to get the best native quality to work with.

I was also surprised at how good the “manual” focus on this little low end camcorder was. looked pretty good! all in all I think im quite happy and will keep my camera. i can always borrow my friends cameras for what little miniDV stuff I still need.

if only there was native support for AVCHD in FCP instead of this pro-res stuff… I’m a poor student and as cheap as harddrives are its 150 bucks i should be spending on food. that said, hopefully the FCP 7 codecs will help.

So thanks for your tips. I’ll let you know how smoothly this edit goes!

[Adam Schoales]

one more thing:

since I dont have an HD TV and really dont care that much about HD anyways I’m likely going to go down to 720 rather than 1080 (it will also save me lots of space). just curious though: 720p30 vs 720p60? What should I use? Does it REALLY matter? is it better to just go with 60 cause its higher, or is there a certain situation where one is better than the other?

thanks!