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03-10-2012, 04:33 PM   #1
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K-5 leveraging the write speed of the UHS-I SDXC Cards

I've been using the Lexar Professional 128GB SDXC card with the K-5, I am using JPEG Large (16M) with **** Quality, and I've noticed the write process takes some time after every picture I take with the Lexar, I would say 1 to 2 seconds on average. Today I tried a SanDisk Extreme Pro 64GB UHS-1 SDXC card and I noticed an important improvement in the writing speed, I would say now consistently is around 1/2 to 1 sec. I know the K-5 will not take any advantage from the UHS-1 card, but for some reason the process seems to be more efficient.

03-10-2012, 11:37 PM   #2
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Despite repeated assurances on these pages that the K-5 cannot read/write any faster than a class 10, I also have noticed that the Sandisk Extreme Pro UHS-1 SD card is faster than the Sandisk Extreme class 10 or any other class 10 card I've tried. I can't explain it but the buffer does empty faster when shooting in fast continuous.
03-11-2012, 01:25 AM   #3
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Well did you test this with the latest firmware 1.13 since that was for improving writing to SDXC cards. So that could be one different.
03-11-2012, 01:38 AM   #4

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QuoteOriginally posted by abmj Quote
Despite repeated assurances on these pages that the K-5 cannot read/write any faster than a class 10,
Really? My impression is that slightly above 18MB/s is the write speed commonly mentioned for the K5.

03-11-2012, 03:10 PM   #5

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I'd like to see some tests on this. These cards are pricey, but if the speed is improved as the two posters here indicate, it would be worth while.
03-11-2012, 08:36 PM   #6
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My "tests" are far from scientific. Using fresh battery, firmware 1.12 and freshly formatted cards (in camera,) I simply ripped off 25 shots in high continuous, as fast as the camera would go. It began to lug down before getting to 25 but I used that number for all tests. As soon as I counted 25, I let go of the shutter release and began timing how long it took for the orange "write" light to stop flickering. I tested some old Class 4, Lexar Platinum II Class 6, Sandisk Extreme Class 10 (30 mb/s) and Sandisk Pro UHS-1 (45 mb/s) cards. The UHS-1 Extreme Pro cards consistently emptied the buffer faster than the Class 10 Extreme cards by a few seconds and blew the Lexars away by a wide margin. YMMV.

The relatively small speed improvement made it hard to justify the significant extra expense, so I only have a couple of the Extreme Pro cards, which I use for occasional sports or other high continuous shooting. The rest of my cards are Extreme 10s, which is just fine for most of what I shoot.
03-11-2012, 10:46 PM   #7

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You wouldn't have your approximate timing by any chance?

A quick check on Amazon, for 32 gb the Lexar platinum class 6 cost $30, the Sandisk class 10 extreme is $56, the UHS-1 extreme is $104.

A quick try with my freshly formatted Sandisk Ultra 8gb class 4 it took 35 secs to shoot 27 shots till write light stopped. Raw. It bogged down around the 20 mark. I have no doubt that it could be improved a bit with a class 6 or better.

Timing was profoundly non professional. Holding down the button while watching a seconds clock count.
03-12-2012, 04:39 AM   #8
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Last edited by Mehlsack; 03-12-2012 at 05:30 AM.
03-12-2012, 06:50 AM   #9
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I've noticed that there is a difference between my 8gb Sandisk Extreme Pro rated @ 30mbs and my 16gb Sandisk Ultra rated @ 30mbs, both when writing to the card, viewing images on the lcd, and when importing it. The Extreme is a class 10 card and the slower Ultra is a class 6 card; but according to a fast google-search the only difference between the two is NTFS vs exFAT formatting of the cards. Which is weird, no?
03-12-2012, 03:50 PM   #10
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QuoteOriginally posted by derekkite Quote
You wouldn't have your approximate timing by any chance? ...
No, sorry. On a related note, I don't use anything larger than 8 GB so the price point isn't quite so painful.
03-12-2012, 08:21 PM   #11
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QuoteOriginally posted by Gimbal Quote
Really? My impression is that slightly above 18MB/s is the write speed commonly mentioned for the K5.

My results
05-07-2012, 08:16 PM - 1 Like   #12
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I believe the small speed increase in the Sandisk Extreme Pro is due to the internal electronics of the card. The Extreme Pro card is using what they call the "Power Core Controller" to chop up and move the data around the card and it is probably performing ECC calculations faster among other things.

A blurb from their sales literature:
"Engineered with the Power Core Controller to deliver faster performance, distributing image data across the card more rapidly and efficiently. Controller's firmware provides greater endurance via wear leveling. Power Core Controller's advanced Error Correction Code (ECC) engine enables better overall data integrity and card reliability during read and write."

This is probably what is edging out the regular "Extreme" cards even though they are both operating at Class 10 speeds in the K-5.

With the Extreme Pro cards being around twice the price of the Extreme cards I don't think the small increase in speed is worth it for the K-5.

Last edited by SuperK5; 05-07-2012 at 08:28 PM.
01-09-2013, 06:42 PM   #13
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K-5 II vs. SDXC???

Hi everyone!

I searched the forum and this is the best thread that came closest to what I am looking for.

I have recently bought a K-5 II camera, but that time my budget allowed only a cheap, slow memory card, to try and play with the machinery, at the time of the purchase and now I am willing to buy a bigger and faster SD card, but I have bumped into several contradictions in this matter. First of all: if I searched for the specification online in reviews and in the official UK and USA websites of Pentax, they all told me, that K-5 II is only compatible with SD and SDHC cards, and it can be compatible with SDXC cards after firmware upgrade ("Removable memory: SD, SDHC, SDXC (via firmware update)"). But when I grab the USER'S GUIDE bundled with the camera, the huge SDXC logo on the cover page is inevitable to notice, and the text says in the document, that SDXC is supported as well. Since I have not found any firmware for K-5 II yet (only for K-5, but that's a different kind of product), I tend to believe to the USER'S GUIDE rather than what is floating around on the internet, BUT I am not sure. Can anyone confirm that K-5 II supports SDXC by default?

If this question is answered there are others that came to my mind:
If K-5 II supports SDXC, does it support UHS-1 as well? Can it utilize the max. 95MB/s r/w speed that the Sandisk Extreme Pro cards offer over the max. 45MB/s r/w speed of the "basic" Sandisk Extreme cards? If the difference is present, and measureable, does it worth the double price (currently extreme pro is around $180 and extreme is around $90 here for 64GB modules)?

And at last: can anyone tell me where are the official K-5 II firmware upgrades located if there are any at all?

Thank you for your help in advance!
01-09-2013, 07:13 PM   #14
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I can't answer any question of yours for sure...

...but I tested the K-5 and there wasn't much of an improvement on SDXC vs SDHC.

I haven't heard that the K-5II is any better in transfer rates. I would be shocked if the K-5II didn't natively support SDXC.
01-09-2013, 09:16 PM   #15
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Ok, because now we are curious, I re-did all the speed tests for the cards at hand(Karen is at a shoot and has 1/2 of the cards with her, so hers are not included): The camera is a K5IIs on Manual with 1/200 shutter speed, iso 80, Sigma 17-50 OS at f2.8 and OS off, the camera on manual focus, RAW images only with all the special stuff off(no highlight protection, etc. - I want just a buffer clear test, not how fast the cameras computer can crunch data), held the shutter button on high speed continuous until slowdown, timed from slowdown until the orange busy light went out, 3 passes for each card averaged. Drum roll...The Sandisk 64gb Extreme Pro UHS-1 Class 10 went 25 pics before slowdown and took 11.5 sec to clear the buffer - card costs $148.00 at Amazon. Kingston 64GB SDXC Class 10 #1 went 25.8 sec., #2 card averaged 28.9 sec(go figure...) They are $48.25 at Amazon. The Transcend 32GB Class 6 SDHC took 25.5 sec and costs $27.21 at Amazon(I think they are discontinued). The Transcend 32GB SDHC Class 10 took 13.6 seconds to clear and costs $23.39 at Amazon. I want to test the 64GB Class 10 Transcend to see if it is as fast as the 32GB one, but the clear winner for price vs speed is the Transcend 32GB class 10, but for future proofing the Sandisk might be the best choice. Ymmv,


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