[Kunzite]

First of all the situations in which one would shoot at a high continuous speed and care about the buffer clearing quickly are probably not situations in which one would disable the AF

Second of all, the five years old Nikon D500 manages 163 MB/s, the X-T4 manages 179 MB/s, the 90D manages 173 MB/s. So the K3 III certainly doesn't offer twice the write speed of 'other recent APS-C models', in fact it manages just a bit over half compared to those with a UHS II slot

Which warrants repetition of my question: why, Pentax, why?!

Adam's card has a maximum of 120MB/s write speed, though.
I'm not saying the K-3iii can write faster than the measured 90MB/sec. I guess we need an answer from Ricoh...

[slartibartfast01]

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!

Did you try the same card in the UHS-1 slot? Others have reported higher write speeds with a UHS-2 card in the UHS-1 slot.

[c.a.m]

Nikon D500 manages 163 MB/s, the X-T4 manages 179 MB/s, the 90D manages 173 MB/s.

These are fairly fast speeds. Is there a reference for the source of the numbers?

- Craig

[FantasticMrFox]

These are fairly fast speeds. Is there a reference for the source of the numbers?

- Craig

My numbers are from this website, which measures camera write speeds with a variety of cards.

[Kunzite]

My numbers are from this website, which measures camera write speeds with a variety of cards.

I'm not seeing the 90D and X-T4 tests on that site...

[FantasticMrFox]

I'm not seeing the 90D and X-T4 tests on that site...

Actually, scratch that, it was this website Sorry for the confusion.

[Kunzite]

Actually, scratch that, it was this website Sorry for the confusion.

OK, thanks, I didn't know of that site - it's updated (unlike the other). No Pentax though.

[phoebus]

Has anyone with the K-3iii tried a write speed test of a UHS II card as a 'drive' in the camera via the USB cable and suitable computer?

That may identify whether the bottle-neck is the UHS interface or image pipe-line... ...if faster speeds can be achieved via USB, then maybe there are some firmware improvements to be found.

I don't (yet) have the K-3iii to test this theory.

[0x4243]

Has anyone with the K-3iii tried a write speed test of a UHS II card as a 'drive' in the camera via the USB cable and suitable computer?

That may identify whether the bottle-neck is the UHS interface or image pipe-line... ...if faster speeds can be achieved via USB, then maybe there are some firmware improvements to be found.

Thats a good idea... I just tried to try it... But doesn't work so far.
The camera only connects via the MTP protocol (media transfer protocol) to the pc and does not allow to copy data onto the card. It allows to delete captures images and the "date" folder though. But doesn't allow to delete the "DCIM" folder.
The camera isnt connected like an usb drive, it is a "digital camera" in windows explorer that is handled differently.


It's a bit strange because one of the ways to update the firmware is - according to the documentation - to copy the file via USB to the card in the camera. Tried this even with an firmware file but nothing is written.

BTW: You can switch from MTP protocol to CD Rom but this just brings up the windows and mac installer of their software - which I think is the most expensive way to distribute software packages...


PS: The K-1 is simply connected as a usb drive an the card inside the K-1 can be written from WIndows... (K-1 can be switched from PTP (picture transfer protocol, a predecessor to MTP) and MSC (Media Mass storage class, like any USB drive)

[phoebus]

Thats a good idea... I just tried to try it... But doesn't work so far.
The camera only connects via the MTP protocol (media transfer protocol) to the pc and does not allow to copy data onto the card.

Thanks for trying - nothing ventured etc..

[Rico]

Has anyone tried testing only one card at a time in Slot 1 (UHS II) leaving Slot 2 empty? Possibly with both slots being used the bus defaults to the UHS I 109 speeds.

[0x4243]

Has anyone tried testing only one card at a time in Slot 1 (UHS II) leaving Slot 2 empty? Possibly with both slots being used the bus defaults to the UHS I 109 speeds.

All my tests were made with only one card at a time in the camera.

[sebberry]

I'll have to measure, but I feel like the time it takes after a burst series (even just a few) and before being able to preview them on the screen seems like an eternity. Any way to speed this up? I feel like I'm waiting a good 10+ seconds before I can preview the shots even after taking just 3-5 shots. Hitting the Play button while the photos are writing to the card just gives me the spinning 'loading' graphic. Is it normal to not be able to preview until they're all flushed from the buffer?

Thanks.

[kwb]

I'll have to measure, but I feel like the time it takes after a burst series (even just a few) and before being able to preview them on the screen seems like an eternity. Any way to speed this up? I feel like I'm waiting a good 10+ seconds before I can preview the shots even after taking just 3-5 shots. Hitting the Play button while the photos are writing to the card just gives me the spinning 'loading' graphic. Is it normal to not be able to preview until they're all flushed from the buffer?

Thanks.

I've just checked and the preview was displayed almost instantaneously while the camera was still writing to the card. This was a burst of 16 shots in Continuous Shooting H with AF-S single point, RAW-only (DNG), ISO 640. I pressed the preview button as soon as I took my finger off of the shutter button. I was ready to use stopwatch app on my ipad to measure time but the preview was quicker than me tapping on my ipad screen.

There could be an unknown (to me) condition where the preview becomes unavailable until all frames are flushed out from the buffer, but even then, 10+ sec for just 3-5 frames sounds too slow to me. Could it be the card or camera-card combination? I'm using Lexar Professional 2000x 64GB SDXC UHS-II card.

[sebberry]

Thanks kwb.

Looks like I was using a standard Class 10 card, I popped in a USH-1 card and it was a fair bit quicker. Might have to invest in a USH-2 card unless the difference is negligible?