K5IIs and K3 Write speed.

I don't have any scientific tests to prove my findings, but having switched to SanDisk many years ago and having tried several types within SanDisk I find that the Extreme Pro cards are the quickest with my K5iis.

Make sure you buy from a reputable source though as it seems that SD cards are a counterfeiters favourite - there's even a buyers guide on how to spot fake SD cards on Ebay

These are some tests done on various cards. Only the K-3 ii was tested......

http://www.cameramemoryspeed.com/pentax-k-3-ii/fastest-sd-card-comparison-test/

So 37MB/s (SLOW!!!) should be possible meaning a RAW of 28MB would take 0.75 secs and 6 shots fully written to the card should take 4.5secs.

Slower cards such as the Ultra 40MB/s cards can take over twice as long.

Note that up to filling the buffer the speed of the card does not matter it's after that that things slow down.

On RAW files the K-5 should be slightly faster than the K-3 for a given number of shots.

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If You have lens correction turned on, it slows processing time significantly!

The K5-II (and s) have pretty much exactly the same processing engine and internals as the K5, which was limited to ~20MB/sec card writes. It doesn't matter what card you use over a certain limir the bottle neck is the camera. Having camera lens distortion and lens corrections turned on will significantly slow down the picture processing as well.

I would still buy decent Sandisk cards. I recently had some of the "ultra" cards rated at 40MB/sec, that is the read rate, not write! Write is significantly slower and I did notice a difference when shooting in burst mode.

I believe for the K3 onwards they started using better/faster internals which can take advantage of faster cards.

The D7100 is not a good camera to demonstrate write speeds...in fact, it is appalling... the appeal to me of Nikon was the very responsive AF and access to the Nikon flash system...however, in CH mode you get a burst of 5-6FPS - Raw and JPEG - but buffer fills within 1 second. You can't use the camera until it has completely cleared and it takes ages. The D3 only tends to manage 9-11 shots before it is out of space... And I have up to date cards. I've joined the D500 club to get over this little issue.

The K-3 and K-5 have always been quite quick to write, I've not noticed much difference between the two. It is nice that, despite the AF not being as responsive as the Nikon, that once you are locked onto the subject you can fire away for over 20 shots, pause and then keep going. Class 10 cards too.

I use a K-5iis side by side with a K-3 at my local kart track. Both are loaded with the Sandisk Extreme Pro 95mb/s and at the end of a burst I am lucky if the card in the iis has completed writing before the karts come round for the next lap. However with the 3 write is well and truly over and I usually have time to review a few shots before the kart come round for the next lap. The difference in write speed is huge!

Thanks for all your replies guys, I finally have made up my mind and not going to get the K3. I don't think I will ever sell my K5IIs and the excellent DA300 but going to invest in another system. (Unless Pentax announces their answer to the D500 very soon:mrgreen.

Most card manufacturers quote read speed, rather than write speed which is often considerably slower.

My 64 GB Lexar Professional 633x SD SC advertises itself as 95 MB/s but that's only read speed, it's write speed is less than half that at 45 MB/s,
Recently bought a 64 GB Panasonic SD SC which correctly labels itself with both read speed of 95 MB/s and more importantly write speed of 90 MB/s

I believe the SanDisk Extreme PRO UHS-I/U3 SDHC Flash Memory Card recommended by Algi also has a read speed of 95 MB/s and a write speed of 90MB/s

I dare say most people knew about this, but it caught me out because some manufacturers, like Lexar, are rather sneaky and only give one number without telling us what that number refers to. If you have checked your cards have a sufficiently high write speed, then the only option is a camera with faster writing ability.

I did get frustrated photographing kayakers going down white water rapids recently with my K-3 II which, like the K-1, uses UHS-I standards. The D500 uses the much faster UHS-II which in theory can write at approx 250MB/s.

PS Nice summary of SD card technology for Pentax cameras here:

I read in an article on PF recently that my camera, the K7, has a write speed maximum of about 25mbps, so I don't bother spending extra money on the fastest ... At present, cards offering 30-40 mbps speeds are considerably cheaper than the latest and greatest, so that's all I buy.

There is actually considerable variation within the 'Class 10' category ... It's really a sort of minimum rating really.

I guess that would be the K1 - full frame I know but designed to write 42mp files but if you prefer you could always set it to cropped aps-c for smaller files, and you could use the DA 300 in both formats.