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A7RII SD card speed and continuous mode


bdp
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I have what I believe is the fastest SD card - a Lexar Professional 2000x 300MB/s card and if I shoot a burst of exposures at the fastest frame rate of even only 4-5 shots, I can't review the shots straight away - instead I get the message 'Writing to card. Unable to operate'.

 

I find this really annoying and I know that SD cards aren't as fast as CF cards but I would have thought that the camera/card could keep up to allow to review the shots a bit sooner.

 

Especially because if I turn Auto Review on the camera gives me an instant review of the last frame. Why can it do this but not allow me to review the shots as they're writing to the card?

 

 

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Two of the Sony's most notable oversights in the A7RII are USB 2.0 instead of 3.1 (somewhat understandable because it is actually a multi port and they want adapter compatibility) and sticking to UHS-I instead of UHS-II for the SD card interface. The camera can't use the full speed of your card. The card is actually falling back to UHS-I speeds that top out at 150MB/s. And even that is theoretically the limit. So SD cards CAN be faster than CF, just Sony chose not to support that standard.

 

 

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Two of the Sony's most notable oversights in the A7RII are USB 2.0 instead of 3.1 (somewhat understandable because it is actually a multi port and they want adapter compatibility) and sticking to UHS-I instead of UHS-II for the SD card interface. The camera can't use the full speed of your card. The card is actually falling back to UHS-I speeds that top out at 150MB/s. And even that is theoretically the limit. So SD cards CAN be faster than CF, just Sony chose not to support that standard.

 

 

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Thanks for that. Annoying that Sony didn't see the need for things like this that presumably would have cost them no more money to implement.

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When a photo is taken it is read into the buffer and then written to the SD card. A RAW file on the a7R ii is around 42 MB, while the UHS-1 bus speed is anywhere from 50 MB/s to 104 MB/s depending on the type of RAM they used. If you are writing a file that is 42 MB in size there just isn't enough available bus speed to read a file from the SD card while writing to it (reading from the SD card while writing to it, kills the read/write speed). Also keep in mind that these Sony cameras are running a pared down version of Android and the processor is also compressing/encoding the JPEG or RAW files as it is clearing the buffer. This encoding/compressing is keeping the processor utilization very high, not leaving CPU cycles to do things like read from the SD card and then display the image.

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When a photo is taken it is read into the buffer and then written to the SD card. A RAW file on the a7R ii is around 42 MB, while the UHS-1 bus speed is anywhere from 50 MB/s to 104 MB/s depending on the type of RAM they used. If you are writing a file that is 42 MB in size there just isn't enough available bus speed to read a file from the SD card while writing to it (reading from the SD card while writing to it, kills the read/write speed). Also keep in mind that these Sony cameras are running a pared down version of Android and the processor is also compressing/encoding the JPEG or RAW files as it is clearing the buffer, this is keeping the processor utilization very high, not leaving CPU cycles to do things like read from the SD card and then display the image.

 

It's definitely a problem. Maybe Sony will fix it with the A7R III. I guess it's a hardware limitation and nothing we can hope will be fixed with a firmware update.

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Yeah, I would not hold out hope for a firmware fix. In some respects, having a proprietary operating system like Canon's DRYOS would be better as it would have less CPU overhead, but then you lose the flexibility Android provides like installing applications.

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I guess no camera is perfect. I have come from Canon and love some things about the Sony but will have to put up with others, and this is one of them. Used it for a paid job yesterday and was apologising to the client while we waited for the images to be written before I could show them the shots on the back of the camera. 

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I guess no camera is perfect. I have come from Canon and love some things about the Sony but will have to put up with others, and this is one of them. Used it for a paid job yesterday and was apologising to the client while we waited for the images to be written before I could show them the shots on the back of the camera. 

bdp, I haven't tried it with a paying client yet but I'm testing a workflow using the remote app not to control the camera but to auto download images to an ipad while I shoot—like a wireless tether—with the purpose of having images to share instantly with clients. I don't have an A7RII yet, and I haven't done enough of my own testing but that might be a solution for you too. I hate showing clients the images on the back of the camera. No 3" screen is good enough.

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bdp, I haven't tried it with a paying client yet but I'm testing a workflow using the remote app not to control the camera but to auto download images to an ipad while I shoot—like a wireless tether—with the purpose of having images to share instantly with clients. I don't have an A7RII yet, and I haven't done enough of my own testing but that might be a solution for you too. I hate showing clients the images on the back of the camera. No 3" screen is good enough.

 

This could be a solution for some jobs but I doubt it would have been useful on my particular job - it's another piece of equipment to carry around and I was outside at a cafe with no assistant, shooting the owner in various places, with lots of customers around etc. The file transfer would surely be way too slow as well. I shoot 95% in a studio, with tethered MF (Hasselblad) and only sometimes need the speed and features of a camera like my Canons or now the Sony.

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WAIT!  4-5 shots? That's about 200MB? That's the damn same size as the shittacular A99's buffer.  you've got to be shitting me. I thought for sure they would have quintupled that size by a 3 years later. 

 

4 to 5 shots per second

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A few years back, Pentax were able to get a firmware update to make the 645D accept SDXC rather than just SDHC, so perhaps it could be done in a firmware update...

The difference between SDXC and SDHC is a file format. There is a physical interface difference between UHS-I and UHS-II.

 

 

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I guess no camera is perfect. I have come from Canon and love some things about the Sony but will have to put up with others, and this is one of them. Used it for a paid job yesterday and was apologising to the client while we waited for the images to be written before I could show them the shots on the back of the camera. 

I have used my Android Nexus 7 tablet with Sony's Remote app:PlayMemories Mobile to shoot and review images as well as EOS Utility and Lightroom do.

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..... .. ... was apologising to the client while we waited

for the images to be written before I could show them

the shots on the back of the camera.

Never had to apologize to a client while waiting

80 seconds for a Polaroid to process ... altho at

times felt need to apologize for dumping all that

toxic Polatrash into their wastebasket :-)

 

`

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Never had to apologize to a client while waiting

80 seconds for a Polaroid to process ... altho at

times felt need to apologize for dumping all that

toxic Polatrash into their wastebasket :-)

 

`

 

Ha, yes I remember those good ole days when we had far fewer shots per job and more patient clients! That polaroid time was always good for a little conversation and cracking jokes - not anymore!

 

Ben

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WAIT!  4-5 shots? That's about 200MB? That's the damn same size as the shittacular A99's buffer.  you've got to be shitting me. I thought for sure they would have quintupled that size by a 3 years later. 

4-5 a sec with over 20 RAW in the buffer. Sony's saving grace is its large buffer but the card write speed is shockingly bad. Check out this users tests: http://alikgriffin.com/best-sd-memory-card-sony-a7rii 

 

35MB/s is ... not even one RAW a sec. 

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I have what I believe is the fastest SD card - a Lexar Professional 2000x 300MB/s card and if I shoot a burst of exposures at the fastest frame rate of even only 4-5 shots, I can't review the shots straight away - instead I get the message 'Writing to card. Unable to operate'.

 

 YOU MIGHT HAVE THE WRONG CARD !!!!!

 

That card is a UHS-II card which gets its faster speed through more connections, so presumably more channels. Only a couple of cameras support that connection (like fuji)

 

You need a UHS-I U3 card to get faster transfer speeds. The one you got will do something like 10mb/s (class 10)

 

From their website "For versatility, the cards also work with UHS-I devices at UHS-I speeds, and they’re backwards compatible with older cameras and readers, performing at Class 10 speeds when used with non-UHS devices." 

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 YOU MIGHT HAVE THE WRONG CARD !!!!!

 

That card is a UHS-II card which gets its faster speed through more connections, so presumably more channels. Only a couple of cameras support that connection (like fuji)

 

You need a UHS-I U3 card to get faster transfer speeds. The one you got will do something like 10mb/s (class 10)

 

From their website "For versatility, the cards also work with UHS-I devices at UHS-I speeds, and they’re backwards compatible with older cameras and readers, performing at Class 10 speeds when used with non-UHS devices." 

 

OMG if you are right I could kiss you!! I will look into it now, but maybe I should just get Sony branded cards....

 

Thanks!

Ben

 

Edit: Just tested an old 32GB Sandisk Extreme Pro SDHC UHS-I Class 10 (U1) 95MB/s card and it is indeed faster than the Lexar in this camera. Easy to test by shooting 5 frames in continuous and then timing how long it takes for the red LED to go out near the card door on the back of the camera. 

 

Memory card specs are SO confusing... Just checked page 57 of the manual and it looks like my Lexar would be the fastest card - SDXC, UHS Speed class 3 -  but obviously I'm not understanding it correctly....

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jaclarkaus - you are a genius. 

 

So the rule is UHS-I cards only, not UHS-II.

 

I can't find this info anywhere in the manual, it just talks about UHS speed class 1 or 3, very confusing.

 

So I have ordered 2 x Sony UHS-I Speed class 10 (U3) cards and when they come I expect them to be even faster than the Sandisk UHS-I (U1) that I just tested, and much  faster than the Lexar card I have which ironically is rated faster but limited by the fact it is a UHS-II card.

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I just tested my A7RII with my 64GB UHS-I U3 SD card (SanDisk) and I got 23-24 high speed continuous shots before the buffer filled. Then I timed the writing those 24 frames to the card. About 22 seconds.

 

Did you have to wait until the end of that 22 seconds before you could press play and review images? I don't mind so much if it takes a while to clear the buffer and write to card, I'd just like to be able to review the first few shots in a burst to check them while it writes.

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Did you have to wait until the end of that 22 seconds before you could press play and review images? I don't mind so much if it takes a while to clear the buffer and write to card, I'd just like to be able to review the first few shots in a burst to check them while it writes.

 

yes, I had to wait for the entire buffer to fill. If auto-review is on, then it only shows the last frame, you cannot see any earlier frames till it has written out to the card completely.

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