The CX12 *was* an entry level consumer cam recording AVCHD compressed MTS files. It was replaced by the HDR-CX300 series. The CX12 is discontinued. The HC9 was the latest in the HDR-HC series (HC1, 3, 5, 7). The HC1 was probably the best of the lot - it is still around under the guise of the HVR-A1 in Sony's professional line-up.
Lens filter diameter:
CX12 & HC9: 37mm: tie
Imaging chip:
CX12: single 1/3.3-inch CMOS
HC9: single 1/2.9-inch CMOS
Larger is generally better. Advantage: HC9
Audio input jack:
CX12: None - unless the proprietary AIS is used.
HC9: 1/8" (3.5m) stereo audio input jack and proprietary AIS.
Advantage: HC9.
built-in infrared emitter ("NightShot" mode):
CX12 & HC9: yes: tie
Optical zoom:
CX12 & HC9: 12x: tie
Recorded video data rate:
HC9: HDV: 25mbps; DV: 25mbps
CX12: AVCHD: 16mbps (best); standard def MPEG2:9mbps
Higher data rate is better: Advantage: HC9
Manual controls:
Basically the same: Tie
Manual audio gain:
HC9: Yes
CX12: No.
Advantage: HC9.
Still features - my opinion: irrelevant. Use a camcorder for video; use a still camera for stills.
Video transfer:
HC9: Connect a firewire cable to the camcorder's DV port and computer's firewire port; import video from digital tape with video editor.
CX12: Place camcorder in dock. Connect USB cable to USB ports on computer and dock. Video editing app dictates whether MTS files copied + transcoded or imported/captured directly to MTS capable video editor.
Note: Software included in the box with a consumer camcorder is useless. Don't bother installing it. Newer Macs include iMovie which is AVCHD/MTS capable. Final Cut is preferred. For Windows, MovieMaker will be challenged by AVCHD/MTS; Sony Vegas and Adobe Premiere are the usual suspects.
No "advantage". The process is what it is. If your computer has no firewire port and there is no way to add one, then getting a miniDV tape based camcorder is pointless.
Video archiving:
CX12: Copy the original MTS data files to a RAID1 multi-drive array set-up.
HC9: After capturing the video, take the digital tape out of the camcorder, lock the tape. This is the archive.
High definition video playback:
CX12: Options include computer file video render and BluRay player playback.
HC9: Options include computer file video render, BluRay player playback and exporting the video project from the computer to the HDV camcorder to digital tape and connecting the HDV camcorder to the HDTV to be used as a HDV deck.
Advantage: HC9.
++++++++++++
The CX12 was an OK camcorder a while ago - the CX300 series is an OK camcorder now. Unless you have specific requirements, you might want to also investigate the Canon HF S series (specifically, the HF S200) if flash memory is the storage method of choice. The Canon HV40 is their entry-level miniDV tape HDV camcorder.
The Sony HDR-HC9 was discontinued - last year, I think - but brought back. It is Sony's entry-level miniDV tape HDV camcorder.
There has never been a large selection of consumer HDV cams, so this is nothing too new. The Sony HDR-HC series and Canon HV series were always about it.
"Converting to DV-AVI" can "hurt" the quality or resolution of video if the video is compressed a lot in that process.
Wich hdv format camcorder can be compared with the sony HDR-CX12?
i was thinking of purchasing a Sony HDR-CX12 AVCHD camcorder but after some research i found that the AVCHD format can be quite difficult to work with but i really like the quality of this camcorder and the options are great especially the multi functional ring on the front. so is there an HDV format camcorder out there that has the same quality and the same options? also why does sony make so many AVCHD camcorders and so little HDV? and if i do decide to buy the CX12. wil converting to DV-AVI hurt the quality or resolution of my footage?

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