Can anyone fill in the blanks re SDHC/SDXC?
Can anyone fill in the blanks re SDHC/SDXC?
Author
Discussion

Otispunkmeyer

Original Poster:

13,602 posts

179 months

Thursday 4th February 2016
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So I just got my RX100 IV and with it I purchased a SDHC card. Its 32 GB, SanDisk Extreme Pro, U3 UHS I, Class 10 95 MB/s speed.

I cannot use it to record anything above standard AVCHD. No 4K, no High Frame Rate.

I cannot see why though, the card appears to be just as quick as the SDXC cards you can buy and it seems the only difference is that one has a H and the other has an X. So what am I missing?

RedThree

163 posts

162 months

Thursday 4th February 2016
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Haven't got any detailed knowledge about the RX100 IV but probably the most important difference is that SDHC uses the FAT32 file system and SDXC exFAT which will affect how the massive files produced by 4K video are written to the card. 4K may also require UHS-II cards to deal with the constant high bandwidth required.
Other surprisingly common issue is whether or not you have a genuine card; there's a hell of a lot of counterfeit cards on the market, sometimes even from apparently serious sources.

Otispunkmeyer

Original Poster:

13,602 posts

179 months

Thursday 4th February 2016
quotequote all
Hmmm I just bought one for £24! lol well we'll see if its a fake or not when it comes. Its from mymemory, they have plenty of good reviews so fingers crossed. Payed through PayPal as well.

I did find a website that tested many different cards on the RX100 IV:

http://alikgriffin.com/best-sony-rx100-iv-memory-c...

UHS-II cards dont appear to let you do 4K at all. UHS-I U3 cards are the way to go, U1's don't give you the full beans either, though its curious that the Transcend U3 card, which is slower than a few of the U1 cards will let you use the full complement of video features where the latter will not. Despite having recorded faster read and writes!

I can only assume SONY don't actually check what the card is capable of and are just looking for something that says this card is SDXC UHS-I U3 Class 10.

RedThree

163 posts

162 months

Thursday 4th February 2016
quotequote all
It has been said by people who should know about these things that if you can find a specific card that has been tested and works properly on your model of camera then that is the one to get. A card that works well on one machine doesn't necessarily work as well on another.
Best of luck!

DibblyDobbler

11,443 posts

221 months

Thursday 4th February 2016
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Spooky - just bought exactly the same thing for my new RX100M2! Only £12 though hehe

Janesy B

2,625 posts

210 months

Friday 5th February 2016
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I made the same error when getting a card for my Sony A6000, got a SDHC Card and it wouldn't let me record in XAVC S - I quickly realised my error and got a SanDisk Extreme Pro SDXC UHS-U3 which works perfect.

As above it's not necessarily about the write speeds but the format of the card. SDHC can take up to 4GB files, SDXC would let you fill the card up with a single file. With the bitrate the filesizes get big, fast. So I can see why it makes you use SDXC.

Otispunkmeyer

Original Poster:

13,602 posts

179 months

Friday 5th February 2016
quotequote all
like you can format a hard disk in any file format you want, what stops you from formatting an SDHC to something better than FAT?

Janesy B

2,625 posts

210 months

Friday 5th February 2016
quotequote all
It's not part of the SDHC standard so compatibility will be patchy at best.