What SD cards do you use? Does anyone use UHS-2 U3 sd cards?

[jatrax]

Sandisk Extreme Pro

Does anyone use UHS-2 U3 sd cards?

Not supported by any Pentax as far as I know. UHS-I only. Might be faster in your card reader assuming it supports them.

[kev.pride]

My understanding is you are limited by the camera itself. I would check your camera requirements first.

[jatrax]

Lots of information here: 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

As you can see the K-3II maxes out at around 36MB/s no matter how fast the card suggesting the bus is maxed at that speed and faster cards are of no use. A faster card might work faster in a card reader that supports faster speeds or for future proofing but not in the K-3II.

Note the K-1 (according to the manual) also only supports UHS-1

[Adam]

What SD cards do you use? Does anyone use UHS-2 U3 sd cards?

The K-3 and newer support UHS-I, which is currently capped out at 95 Mb/s read and 90 Mb/s write in sandisk extreme pro cards.

As you can see the K-3II maxes out at around 36MB/s no matter how fast the card suggesting the bus is maxed at that speed and faster cards are of no use. A faster card might work faster in a card reader that supports faster speeds or for future proofing but not in the K-3II.

This sounds wrong to me. This would hold true for the K-5 series, but UHS-I can and does write way faster. You should also be able to get very fast read speeds over USB, assuming you're connected to a USB3 port and your computer's bus is fast enough.

See:
Pentax K-3 Review - Performance and Burst Mode | PentaxForums.com Reviews

[kenspo]

On K-3II i use the Lexar Pro x633 and x1000 cards. Works perfect. On K-1 i will use x1000 and x2000 cards. But on K-3/K-3II the x633 cards is all you need.

Im just in the same lucky position with Lexar, as i am with Ricoh!

[joergens.mi]

This sounds wrong to me. This would hold true for the K-5 series, but UHS-I can and does write way faster. You should also be able to get very fast read speeds over USB, assuming you're connected to a USB3 port and your computer's bus is fast enough.

See:
Pentax K-3 Review - Performance and Burst Mode | PentaxForums.com Reviews

From my experiments, i can't agree, die K3 itself can't write faster than 36 maybe 40 MB/sec to any card. There is no need for an UHS-I card according to speed.

I hope the K-1 will be faster at this point.

[victormeldrew]

I recently picked up a couple of Sandisk Extreme Pro 32GB cards (2 for 1 offer, so I didn't think twice) to replace my Sandisk Ultra cards in my K-3II - theoretically ~90MB/s instead of ~20MB/s
I write RAW to both cards for backup. A full buffer of continuous shooting would take close to a minute to finish writing with the old cards, now it is done in ~20s
This seems to suggest that it is indeed capped at around 40MB/s rather than using the full potential. Otherwise it would be 4-5 times faster.
Obviously the read speed in my USB3 card reader is much quicker than before, and there are some other benefits like better environmental protection. But if in-camera performance is all that matters then a lower end card would be sufficient.

[kenspo]

Most importers of Pentax, at least in this area, just switched completely from SanDisk to Lexar..Just saying'

[Na Horuk]

Exactly, camera will limit you before SD card. Sure, maybe you still want fast SD card so you can use it in future cameras, so you can transfer files to computer faster.. but I don't think paying a lot of money for super fast SD makes sense. I think pretty much everything above 70MB/s will be good enough, even for HD video or burst mode photography

Go with a Sandisk, some decent speed and the capacity you want. Can't go wrong. Just make sure you don't get a fake - it has happened before, with people buying online from weird stores/people.

Lexar is probably fine, too. Some people like Transcend. I stay away from Sony and Panasonic cards. Sandisk has been a favourite on these forums for a long time

[victormeldrew]

Fakes are a major problem with cards now, especially on certain online marketplaces...anyone can print a sticker and a blister pack and put it a cheap no-name card in there - and there is next to no way to confirm authenticity. Sticking to an approved/major retailer is the only good way.

But I would say there is a reason for pro cards (which come with fast speeds by default) - that is the extra protection...environmental, x-ray and ESD proofing, and free recovery software. All potentially useful to some.

[stevebrot]

From my experiments, i can't agree, die K3 itself can't write faster than 36 maybe 40 MB/sec to any card. There is no need for an UHS-I card according to speed.

I hope the K-1 will be faster at this point.

I am curious as to how you measure this. Would you care to give a step-by-step description?


Steve

[TheOneAndOnlyJH]

I am curious as to how you measure this. Would you care to give a step-by-step description?
Steve

I can't say exactly how he measured it, but the quick and dirty way is to set the camera to burst mode and time how long it takes to shoot about a hundred pictures without taking your finger off the trigger. Start a timer when you take your first shot and stop when the SD light stops blinking after you are finished. The first few seconds will be rapid as the buffer fills up, and then the camera will shoot at a slower rate, which is limited by how fast it can write to the card. After you take your finger off the shutter, it will continue to write to the SD card until the buffer is empty and the SD card access light will then stop blinking.

Then pop your memory card into a computer and see how much has been written to the card. Divide total MB by the time you measured and you'll have a rough measurement of how quickly the camera was writing to the card in MB/sec.

If you try this, do it on an empty SD card you just formatted. Flash memory writes in blocks, and as you fill the memory and delete pictures some blocks are only partially filled, which causes the card to read and write slower (even after you delete files) because flash memory has to read whole chunks even if they are only partly filled. When you format a memory card it should be back to full speed.

[wtlwdwgn]

Lately I've also been using the Lexar UHS-1 633X cards and the cards and buffer write fast enough that I seldom fill the buffer shooting DNG raw in my
K-3. Just my $0.02.

[stevebrot]

I can't say exactly how he measured it, but the quick and dirty way is to set the camera to burst mode and time how long it takes to shoot about a hundred pictures without taking your finger off the trigger. Start a timer when you take your first shot and stop when the SD light stops blinking after you are finished. The first few seconds will be rapid as the buffer fills up, and then the camera will shoot at a slower rate, which is limited by how fast it can write to the card. After you take your finger off the shutter, it will continue to write to the SD card until the buffer is empty and the SD card access light will then stop blinking.

Then pop your memory card into a computer and see how much has been written to the card. Divide total MB by the time you measured and you'll have a rough measurement of how quickly the camera was writing to the card in MB/sec.

If you try this, do it on an empty SD card you just formatted. Flash memory writes in blocks, and as you fill the memory and delete pictures some blocks are only partially filled, which causes the card to read and write slower (even after you delete files) because flash memory has to read whole chunks even if they are only partly filled. When you format a memory card it should be back to full speed.

That is how I figured it was being done.

That method assumes that all data in the buffer is fully processed and marshalled leaving only the write phase of buffer flush to slow the process. Writing to card is (usually, at least in a well-designed flow) the last and minor part of the sequence. I may be wrong, but aside from some possible debug/service menu, I don't believe that the start/stop for card write is accessible. That may be why Imaging-Resource.com measures "buffer clear time". Even then it is an estimate since there are several ways to manage buffers for async processes. Cycle time with non-full buffer is probably a better estimate.


Steve