HX9V maximum processing/writing/recording speed in relation to memory cards

[osupics]

hi all,

i have been wondering if anyone might know what the maximum speed capabilities of the HX9V are when it comes to processing/writing/recording pics and movies in relation to choosing compatible memory cards?

there are some SDHC cards on the market that are able to reach speeds of up to 95 MB/s which im aware can not be utilised by the HX9V though there are others in the 30-45 MB/s range.

the only thing my not particularly techie mind can ascertain from the specs is that the camera can process at best in movie mode 24 Mbps (AVCHD 1920 x 1080 (50i) so i assume a 30 MB/s speed card would do the job for speedy writing/recording of pics and movie ?

(would still be interesting to know what the cameras exact limits are though)

cheers

[Mick2011]

Hi osupics

osupics wrote:
there are some SDHC cards on the market that are able to reach speeds of up to 95 MB/s which im aware can not be utilised by the HX9V though there are others in the 30-45 MB/s range.

The manual says to use a minimum Class 4 card but given the variance between 'cheap' and 'quality' card read/write speeds, I'd suggest you get the fastest card you can afford. To be on the safe side for optimum performance, I'd suggest HD video recording in particular needs a card that has a speed rating of at least Class 6.

Beyond that, the biggest advantage of a faster card is in the increased upload (read) speeds when transferring to your PC, although on th HX9V you will also get improved buffer transfer (write) rates, which can be important for Continuous mode shooting as well as HD video recording. So while it's not true that the camera can't utilise these super-fast card speeds, the advantages will depend on the way you shoot and how impatient you are when uploading!

the only thing my not particularly techie mind can ascertain from the specs is that the camera can process at best in movie mode 24 Mbps (AVCHD 1920 x 1080 (50i) so i assume a 30 MB/s speed card would do the job for speedy writing/recording of pics and movie ?

I should point out there's quite a big difference between 24Mbps and 30MBps: 24 mega-bits (Mb) is a 8 times less data than 24 megabytes (MB), although that doesn't really clarify the issue... bitrates are an indication of the quality of the video both in recording and playback; actual data throughput to the card while recording (in MB) can and does vary considerably and while the data transfer rate required by the camera will go up with high bitrate recording, there's no direct correlation here. Transfer rates will go up with high buffer levels, conceivably peaking over 30MB/s, so a fast card becomes more relevant as quality levels rise (see last paragraph).

(would still be interesting to know what the cameras exact limits are though)

A short answer at last: I don't know either! I've never seen any test results, nor can I figure out how you would gather the data. Maybe another user could contribute...

Cheers

Mick

[osupics · Accepted solution]

Hi Mick,

thanks for the detailed response.

i ended up contacting sandisk who are the makers of the 95 MB/s cards (extreme pro SDHC) i was looking at and they informed me that they had done tests with the HX9V which showed that such high speeds could not be utilised by the camera for their product and pointed me to their other cards which were 30 MB/s and lower (extreme, ultra series). they also pointed me to a tool they have on their website that shows compatibility with all devices they have tested their cards on.

cheers

[Mick2011]

Good to hear you got somewhere

Interesting to hear from SanDisk. All I'd add is that there's no incompatibility with faster cards as such, just a question of whether you can justify paying for the faster data transfer rates they offer. USB2 tops out at 60MB/s: you won't get 60MB/s uploads from a 30MB/s card! Given the very large capacity of the HC cards, you'd only really want one if you shoot lots of HD video.

If you're using a quality brand like SanDisk you certainly shouldn't have any problems with the card they recommend in your camera. Do make sure you're buying genuine branded products from a reputable dealer; there are a lot of fakes around (especially among online traders) which will give you seriously impaired performance.

Cheers

Mick