Anyone really measured the UHS-II write speed in the camera?

gatorguy · 01-07-2022, 06:01 AM

Originally posted by idontstairs

The Nikon Z6 doesn't use a UHS-II card. I spent a day shooting 4k UHD in 97 degree high noon sunshine and couldn't get mine to overheat.

---------- Post added 01-06-22 at 10:44 PM ----------

I feel we are going in circles slapping a dead mirror here.

We will review again. Two known facts 1) The PentaxK-3iii camera has a UHS-II card slot. 2) The Pentax K-3iii camera doesn't utilize the full write speed of the UHS-II card slot.

Questions asked - Why doesn't Pentax use the full buffer? Why would Pentax purposely gimp the buffer?
.

It's pretty much true across the board that our current crop of cameras, Nikon, Canon, Fuji, Pentax, etc,, do not write to the UHS-II cards as fast as the standard allows. I already offered Nikon discussion links on the topic, and a tech paper that tested write speeds on the Canon R5 proved that most UHS-II cards are giving only about 60 percent the sustained write speed the standard allows for. Is it Nikon/Canon gimping their hardware? I have no idea. I just know what the tests are showing.

Last edited by gatorguy; 01-07-2022 at 07:16 AM.

JPT · 01-07-2022, 06:49 PM

I got my cards yesterday and tried to do a simple test as close to kwb's as possible, but I'm not as scientific or controlled.

The card is a Lexar Silver Series 1667x UHS II which claims 250MB/s read and 120MB/s writeon the package.

I found that it shot 40 images then slowed down for another 4. The wait until the write was completed was another 10 seconds. So I think this is close to the performance of the more expensive Gold Series card that kwb tested, and faster than the UHS I card.

gatorguy · 02-27-2022, 08:40 AM

Originally posted by Adam

I performed a test with this card:
Lexar 128GB Professional 1667x UHS-II SDXC Memory LSD128CBNA1667

With all corrections and AF disabled, shooting until the buffer filled up, the measured write speed averaged out to 91 Mb/s in raw in 84 Mb/s in raw+. Perhaps not cutting edge, but that is a 2x speedup over the K-3 II (and other recent APS-C models) and a 3x speedup over the K-1. I'd consider that a job well done by Pentax!

That's not far off from the max sustained write speeds for that card, 104 mb/s in actual performance testing. For giggles Adam could you try testing it with a smaller 32 or 64gb Lexar Profesional 2000x, or a Sony Tough, or Delkin 2000x? None of the cards ever perform to the package specs, but those three are among the fastest in actual use, hovering around 135-150mb/s on something like a Fuji XT3, 150-170mb/s on a Canon EOS-R.

The Pentax may indeed be far slower, but the actual write speeds in practice are all over the place from different brands with the same stated speed ratings on the package.

gatorguy · 03-14-2022, 07:33 AM

From my own tests today, and repeated several times to verify:
Sony tough UHS-II - 12.4 seconds to clear buffer after filling with approx 36 images in high-speed burst
Lexar 1667x UHS-II - 15.8 seconds to clear
Lexar 633x UHS-I - 38.8 seconds to clear

The Sony Tough was noticeably faster in practice than any of my other cards which include these UHS-II's: Sony Extreme Pro, Lexar 1667, ProGrade V60, Angelbird V60

**c.a.m** · 03-14-2022, 07:45 AM

Originally posted by gatorguy

From my own tests today, and repeated several times to verify:

Your results are similar to the test done by member @kwb, at post 51 above: https://www.pentaxforums.com/forums/210-pentax-k-3-iii/426099-anyone-really-...ml#post5487437

- Craig

red5isalive · 03-10-2023, 11:14 AM

That's a difficult matter to find the correct information online,

Some years ago I did found myself also willing to know this and found that website that I think is the best one in order to understand writting speeds:
Pentax K-3 II SD Card Write Speed Comparison of Fastest Memory Cards for the Pentax K3 II Digital Camera - Camera Memory Speed Comparison & Performance tests for SD and CF cards

BR,

Urnamaster13 · 03-18-2023, 01:52 PM

Considering that only 1 slot is UHS II, what could be the ideal way to use dual sd cards ? If we want to keep a live backup while shooting in 2nd card...

Should we use UHS I cards in both slot to maintain same speed ?

**bspn** · 03-18-2023, 03:59 PM

Originally posted by Urnamaster13

Considering that only 1 slot is UHS II, what could be the ideal way to use dual sd cards ? If we want to keep a live backup while shooting in 2nd card...

Should we use UHS I cards in both slot to maintain same speed ?

Why would the cards being the same speed have any importance?

Urnamaster13 · 03-18-2023, 04:27 PM

Originally posted by bspn

Why would the cards being the same speed have any importance?

Will performance be same while shooting bursts if using a V30 card and V90 in different slots ?

gatorguy · 03-18-2023, 04:34 PM

Originally posted by Urnamaster13

Will performance be same while shooting bursts if using a V30 card and V90 in different slots ?

Yes.

Use UHSII in both slots, or only in slot one. For simplicity I don't use UHS1 cards anymore except in my K-70, and then only because I don't want the ones I already had purchased going to waste. If you have two different speed UHSII cards put the faster one in slot 1. It can't hurt.

For what it's worth there have been other flagships with one slot faster than the other.

**bspn** · 03-18-2023, 07:14 PM

Originally posted by gatorguy

Yes.

Use UHSII in both slots, or only in slot one. For simplicity I don't use UHS1 cards anymore except in my K-70, and then only because I don't want the ones I already had purchased going to waste. If you have two different speed UHSII cards put the faster one in slot 1. It can't hurt.

For what it's worth there have been other flagships with one slot faster than the other.

My thinking was if shooting raw to slot 1 and jpeg to slot 2, the file size difference should more than make up for the slower write in slot 2. If using card 1, and when it fills up, writing to card 2 may be a bit slower, but so what?

Urnamaster13 · 03-19-2023, 02:09 AM

Originally posted by gatorguy

Yes.

Use UHSII in both slots, or only in slot one. For simplicity I don't use UHS1 cards anymore except in my K-70, and then only because I don't want the ones I already had purchased going to waste. If you have two different speed UHSII cards put the faster one in slot 1. It can't hurt.

For what it's worth there have been other flagships with one slot faster than the other.

Considering k3-3 has 1 UHS-II slot and UHS-I slot, if i want to shoot with 2 cards, simulatenously writing to both in duplicates( RAW only) in case either one card fails...the speed should not be a problem while shooting bursts ?

i read in a post above you said that the Sony tough performed fastest. I am delibrating between getting it and the lexar 1667

**bspn** · 03-19-2023, 07:34 AM

Originally posted by Urnamaster13

Considering k3-3 has 1 UHS-II slot and UHS-I slot, if i want to shoot with 2 cards, simulatenously writing to both in duplicates( RAW only) in case either one card fails...the speed should not be a problem while shooting bursts ?

i read in a post above you said that the Sony tough performed fastest. I am delibrating between getting it and the lexar 1667

I use the Lexar 1667 UHS-II in slot 1 and have been pleased. I have not done any time studies but I don't do long bursts and haven't noticed a buffer full scenario, yet. I have not had RAW writes to both cards simultaneously either.

zapp · 05-08-2023, 09:55 AM

Made my own tests, UHS-II was insignificantly faster, so I stick to UHS-I. More than 3s of full burst are fine for me - afterwards video starts. I was able to rach 12fps. Use different shutter speeds, add AF in the equation and you get a sustained rate of close to 10 fps for 4s....
UHS-II probably wins for video applications with sustained speed, it wins for data transfer to PC.

Long time ago I worked with a Canon T90 and an SSC 1.4/50. At 4.5 fps the aperture ring started to move by itself unless fixed at A. K3iii with 12fps is a monster. Today it is a questions who survives longer, the aperture mechanism or the shutter. Btw, I really love the idea of no mechanical shutter. Fast fps and minimum mechanical movement.

01-07-2022, 06:49 PM	#62
JPT Pentaxian Join Date: Jan 2012 Location: Tokyo Photos: Gallery Posts: 2,821	I got my cards yesterday and tried to do a simple test as close to kwb's as possible, but I'm not as scientific or controlled. The card is a Lexar Silver Series 1667x UHS II which claims 250MB/s read and 120MB/s writeon the package. I found that it shot 40 images then slowed down for another 4. The wait until the write was completed was another 10 seconds. So I think this is close to the performance of the more expensive Gold Series card that kwb tested, and faster than the UHS I card. Last edited by JPT; 01-07-2022 at 07:10 PM.

03-19-2023, 02:09 AM	#72
Urnamaster13 Senior Member Join Date: Dec 2014 Location: Surat Photos: Albums Posts: 130	Originally posted by gatorguy Yes. Use UHSII in both slots, or only in slot one. For simplicity I don't use UHS1 cards anymore except in my K-70, and then only because I don't want the ones I already had purchased going to waste. If you have two different speed UHSII cards put the faster one in slot 1. It can't hurt. For what it's worth there have been other flagships with one slot faster than the other. Considering k3-3 has 1 UHS-II slot and UHS-I slot, if i want to shoot with 2 cards, simulatenously writing to both in duplicates( RAW only) in case either one card fails...the speed should not be a problem while shooting bursts ? i read in a post above you said that the Sony tough performed fastest. I am delibrating between getting it and the lexar 1667 Last edited by Urnamaster13; 03-19-2023 at 02:37 AM.

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01-07-2022, 06:01 AM	#61
gatorguy Moderator Join Date: Feb 2015 Location: Central Florida Photos: Gallery Posts: 6,092	Originally posted by idontstairs The Nikon Z6 doesn't use a UHS-II card. I spent a day shooting 4k UHD in 97 degree high noon sunshine and couldn't get mine to overheat. ---------- Post added 01-06-22 at 10:44 PM ---------- I feel we are going in circles slapping a dead mirror here. We will review again. Two known facts 1) The PentaxK-3iii camera has a UHS-II card slot. 2) The Pentax K-3iii camera doesn't utilize the full write speed of the UHS-II card slot. Questions asked - Why doesn't Pentax use the full buffer? Why would Pentax purposely gimp the buffer? . It's pretty much true across the board that our current crop of cameras, Nikon, Canon, Fuji, Pentax, etc,, do not write to the UHS-II cards as fast as the standard allows. I already offered Nikon discussion links on the topic, and a tech paper that tested write speeds on the Canon R5 proved that most UHS-II cards are giving only about 60 percent the sustained write speed the standard allows for. Is it Nikon/Canon gimping their hardware? I have no idea. I just know what the tests are showing. Last edited by gatorguy; 01-07-2022 at 07:16 AM.

02-27-2022, 08:40 AM	#63
gatorguy Moderator Join Date: Feb 2015 Location: Central Florida Photos: Gallery Posts: 6,092	Originally posted by Adam I performed a test with this card: Lexar 128GB Professional 1667x UHS-II SDXC Memory LSD128CBNA1667 With all corrections and AF disabled, shooting until the buffer filled up, the measured write speed averaged out to 91 Mb/s in raw in 84 Mb/s in raw+. Perhaps not cutting edge, but that is a 2x speedup over the K-3 II (and other recent APS-C models) and a 3x speedup over the K-1. I'd consider that a job well done by Pentax! That's not far off from the max sustained write speeds for that card, 104 mb/s in actual performance testing. For giggles Adam could you try testing it with a smaller 32 or 64gb Lexar Profesional 2000x, or a Sony Tough, or Delkin 2000x? None of the cards ever perform to the package specs, but those three are among the fastest in actual use, hovering around 135-150mb/s on something like a Fuji XT3, 150-170mb/s on a Canon EOS-R. The Pentax may indeed be far slower, but the actual write speeds in practice are all over the place from different brands with the same stated speed ratings on the package.

03-14-2022, 07:33 AM	#64
gatorguy Moderator Join Date: Feb 2015 Location: Central Florida Photos: Gallery Posts: 6,092	From my own tests today, and repeated several times to verify: Sony tough UHS-II - 12.4 seconds to clear buffer after filling with approx 36 images in high-speed burst Lexar 1667x UHS-II - 15.8 seconds to clear Lexar 633x UHS-I - 38.8 seconds to clear The Sony Tough was noticeably faster in practice than any of my other cards which include these UHS-II's: Sony Extreme Pro, Lexar 1667, ProGrade V60, Angelbird V60

03-14-2022, 07:45 AM	#65
c.a.m Site Supporter Join Date: Jan 2013 Location: Ottawa, Canada Photos: Gallery \| Albums Posts: 4,189	Originally posted by gatorguy From my own tests today, and repeated several times to verify: Your results are similar to the test done by member @kwb, at post 51 above: https://www.pentaxforums.com/forums/210-pentax-k-3-iii/426099-anyone-really-...ml#post5487437 - Craig

03-10-2023, 11:14 AM	#66
red5isalive Pentaxian Join Date: Nov 2013 Location: Barcelona Posts: 659	That's a difficult matter to find the correct information online, Some years ago I did found myself also willing to know this and found that website that I think is the best one in order to understand writting speeds: Pentax K-3 II SD Card Write Speed Comparison of Fastest Memory Cards for the Pentax K3 II Digital Camera - Camera Memory Speed Comparison & Performance tests for SD and CF cards BR,

03-18-2023, 01:52 PM	#67
Urnamaster13 Senior Member Join Date: Dec 2014 Location: Surat Photos: Albums Posts: 130	Considering that only 1 slot is UHS II, what could be the ideal way to use dual sd cards ? If we want to keep a live backup while shooting in 2nd card... Should we use UHS I cards in both slot to maintain same speed ?

03-18-2023, 03:59 PM	#68
bspn Loyal Site Supporter Join Date: Apr 2021 Location: Northern MI Posts: 663	Originally posted by Urnamaster13 Considering that only 1 slot is UHS II, what could be the ideal way to use dual sd cards ? If we want to keep a live backup while shooting in 2nd card... Should we use UHS I cards in both slot to maintain same speed ? Why would the cards being the same speed have any importance?

03-18-2023, 04:27 PM	#69
Urnamaster13 Senior Member Join Date: Dec 2014 Location: Surat Photos: Albums Posts: 130	Originally posted by bspn Why would the cards being the same speed have any importance? Will performance be same while shooting bursts if using a V30 card and V90 in different slots ?

03-18-2023, 04:34 PM	#70
gatorguy Moderator Join Date: Feb 2015 Location: Central Florida Photos: Gallery Posts: 6,092	Originally posted by Urnamaster13 Will performance be same while shooting bursts if using a V30 card and V90 in different slots ? Yes. Use UHSII in both slots, or only in slot one. For simplicity I don't use UHS1 cards anymore except in my K-70, and then only because I don't want the ones I already had purchased going to waste. If you have two different speed UHSII cards put the faster one in slot 1. It can't hurt. For what it's worth there have been other flagships with one slot faster than the other.

03-18-2023, 07:14 PM	#71
bspn Loyal Site Supporter Join Date: Apr 2021 Location: Northern MI Posts: 663	Originally posted by gatorguy Yes. Use UHSII in both slots, or only in slot one. For simplicity I don't use UHS1 cards anymore except in my K-70, and then only because I don't want the ones I already had purchased going to waste. If you have two different speed UHSII cards put the faster one in slot 1. It can't hurt. For what it's worth there have been other flagships with one slot faster than the other. My thinking was if shooting raw to slot 1 and jpeg to slot 2, the file size difference should more than make up for the slower write in slot 2. If using card 1, and when it fills up, writing to card 2 may be a bit slower, but so what?

03-19-2023, 07:34 AM	#73
bspn Loyal Site Supporter Join Date: Apr 2021 Location: Northern MI Posts: 663	Originally posted by Urnamaster13 Considering k3-3 has 1 UHS-II slot and UHS-I slot, if i want to shoot with 2 cards, simulatenously writing to both in duplicates( RAW only) in case either one card fails...the speed should not be a problem while shooting bursts ? i read in a post above you said that the Sony tough performed fastest. I am delibrating between getting it and the lexar 1667 I use the Lexar 1667 UHS-II in slot 1 and have been pleased. I have not done any time studies but I don't do long bursts and haven't noticed a buffer full scenario, yet. I have not had RAW writes to both cards simultaneously either.

05-08-2023, 09:55 AM	#74
zapp Pentaxian Join Date: Jul 2011 Posts: 2,385	Made my own tests, UHS-II was insignificantly faster, so I stick to UHS-I. More than 3s of full burst are fine for me - afterwards video starts. I was able to rach 12fps. Use different shutter speeds, add AF in the equation and you get a sustained rate of close to 10 fps for 4s.... UHS-II probably wins for video applications with sustained speed, it wins for data transfer to PC. Long time ago I worked with a Canon T90 and an SSC 1.4/50. At 4.5 fps the aperture ring started to move by itself unless fixed at A. K3iii with 12fps is a monster. Today it is a questions who survives longer, the aperture mechanism or the shutter. Btw, I really love the idea of no mechanical shutter. Fast fps and minimum mechanical movement.