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03-20-2011, 11:24 PM   #61
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I'm right around that 20-25 second mark with my Silicon Power class 10 card as well, I'll have to time it. Smeggy, as for your drive by's maybe you need a second "gun" for when one is reloading

03-21-2011, 12:56 AM   #62
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QuoteOriginally posted by Christine Tham Quote
Pity Firmware 1.03 hobbles the write rate slightly
Isn't the difference only 1 fps? Fail to see what possible effect that could have in the real world!
03-21-2011, 01:18 AM   #63
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QuoteOriginally posted by ozlizard Quote
Isn't the difference only 1 fps? Fail to see what possible effect that could have in the real world!
The fps remains the same.

A slightly slower write rate (I'm guessing 5-10%, data is not conclusive, merely suggestive) just means it's slower to clear the buffer. That does affect usability, since when the buffer fills the camera is locked out until the buffer partially clears.

The difference is not really that significant. What is significant is a LACK of improvement.

What would have been nice is if the K-5 could improve sustained write rate to say 20 MB/s on this new card, which is supposedly able to reach up to 45 MB/s. The theoretical max transfer rate is 25 MB/s in HS mode. There ARE cameras that can write at 20 MB/s - for example the Canon pro cameras will on a good SDHC card.

17-8 MB/s is nothing special - lots of cameras can achieve that on even cheap class 10 cards.
03-21-2011, 02:27 AM   #64
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QuoteOriginally posted by Christine Tham Quote
The fps remains the same.
Yeah sorry my typo, I meant transfer rate not fps. Remember that the K5 is not really a "pro" camera in all respects and this is probably one of them!

03-21-2011, 03:47 AM   #65
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QuoteOriginally posted by ozlizard Quote
Remember that the K5 is not really a "pro" camera in all respects and this is probably one of them!
Actually, I think it's THE *best* high fps camera that Pentax has produced to date.

Previous Pentax cameras were not really serious contenders for continuous shooting. 7fps for about 20-25 shots in Raw mode is excellent, and better than any other camera in it's class.

The Canon EOS 1D can do about 28 shots in 10fps in raw mode. Yes, less than 3 seconds of shooting. [The saving grace is that the 1D can write out it's buffer at 30-40 MB/s on a good CF card]

For probably the first time in Pentax DSLR history, Pentax owners can finally have a taste of the joys of continuous shooting that Canon and Nikon pro camera owners have known for some time.

As an example, this is a shot that's relatively easy to achieve on a EOS 1D (the precise moment when the galah snatches the coin from the hand) but I've tried half a dozen times on the K10D without any success:


Managed to nail a similar shot on the K-5 on first try:


And here's one from yesterday - the bird spent less than a second snatching a bit of doughnut, but the K-5 captured it no problems:

Last edited by Christine Tham; 03-21-2011 at 03:52 AM.
03-21-2011, 08:28 AM   #66
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QuoteOriginally posted by Hound Tooth Quote
Some things worth pointing out: you can disable JPGs all you want, the camera still generates a JPG file for every shot (and embeds it into the the RAW file). So image processing still happens every time, regardless of your settings. Also, the embedded JPG is 16MP and heavily compressed, even if you set JPG files to be only 2MP. There's a lot more involved here than raw file writing speed. That's why I set the white balance to a fixed amount, that way the camera isn't doing its own WB calculations.
i wonder if this is something that could be fixed in a firmware update, so that if you choose to shoot RAW only it leaves out the jpeg all together. The amount of processing time for the buffer would definitely benifit, as it could start writing sooner and have less load on the processor in general.
03-21-2011, 08:37 AM   #67
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QuoteOriginally posted by Christine Tham Quote
Actually, I think it's THE *best* high fps camera that Pentax has produced to date.

For probably the first time in Pentax DSLR history, Pentax owners can finally have a taste of the joys of continuous shooting that Canon and Nikon pro camera owners have known for some time.
As a fan of FPS I can say I agree.
However, if I could nit-pick it on the K-5, it would be for a more modest mid continuous shutter. I find the 7fps vs 1.5 fps to be an all or nothing. But a 3 - 3.5 FPS would be so much better imo.

I wonder if they could do that in a firmware?

Anyways maybe that's just my K20D experience making me say that because I really didn't a problem with 3FPS tbh.
03-21-2011, 09:03 AM   #68
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QuoteOriginally posted by JohnBee Quote
I wonder if they could do that in a firmware?
They most certainly can change the FPS rate in firmware, they could let the user select anywhere from 1-7 FPS even in 1/2 or lower steps.

As for the Jpeg part of it.. I don't see why they couldn't. Currently the firmware tells the camera to shoot RAW, process and embed the jpeg, write RAW file if user has it selected, then write the jpeg if the user has it selected, delete the RAW file if user has jpeg only selected. So I don't see why they can't let the second step be optional like the 4th and 5th step are. It would simply negate step 4 as well unless you selected RAW+

03-21-2011, 11:50 AM   #69
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The K-5 cannot take advantage of the Extreme pro because it is NOT compliant to the UHS standard (as stated in Pentax press release which came with firmware 1.02).
The card falls back on the normal bus which is a tad slower than the Extreme III as you can read on Rob Galbraith's site.
The Nikon D7000 does support the UHS bus and the D7000 reaches a 10% higher speed than the normal Extreme III:

Nikon D7000 RAW Burst Test

In Europe though the card is not more expensive or even a tad cheaper than the Extreme III so I would recommend the PRO because it is more future proof and the upload speed to your PC can be faster when used with an appropriate reader.
03-21-2011, 02:07 PM   #70
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QuoteOriginally posted by JohnBee Quote
As a fan of FPS I can say I agree.
However, if I could nit-pick it on the K-5, it would be for a more modest mid continuous shutter. I find the 7fps vs 1.5 fps to be an all or nothing. But a 3 - 3.5 FPS would be so much better imo.
Agree.

3fps is very useful for portraits - people tend to stiffen unnaturally when they pose for a photo, and by the 3rd or 4th shot they have loosened up just sufficiently to look nice (because they hear the sound of the first shutter and relax thinking it's all over).

I really like the 3fps "unlimited" JPEG mode on the K10D - great for street photography.

The Canon EOS 1D will allow the user to selectively dial in fps, but I must admit I have never used that feature. The camera will shoot over 100 frames in 10fps in JPEG mode - the shutter sound is so scary people have been known to move away from me!
03-21-2011, 05:32 PM   #71
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To be clear, I don't think this necessarily has anything to do with the camera's writing speed. I think what we're seeing is the image processing speed limit of the camera. As I mentioned above, even in RAW mode, the camera is still processing each and every image to generate an embedded preview in the RAW file. Only so many images can be stored in the buffer at any one time, and once that buffer is full, images trickle out as fast as the processing engine can push them. This is probably why shooting RAW and RAW+ both yield about 25 images before the buffer fills up, and the "writing" light only stays on for a tiny bit longer in RAW+.

If firmware 1.03 seems the tiniest bit slower (and negligibly so), it's probably due to some improved stability in the source code to prevent some of the lockups that have been plaguing early adopters.
03-21-2011, 05:36 PM   #72
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QuoteOriginally posted by JohnBee Quote
However, if I could nit-pick it on the K-5, it would be for a more modest mid continuous shutter. I find the 7fps vs 1.5 fps to be an all or nothing. But a 3 - 3.5 FPS would be so much better imo.
This came as a surprise to me when I got the K-5. The K-7 choices were 5.2fps and 3fps. For some bizarre reason, Pentax decided to make the K-5 choices either 7fps or... 1.5fps (wtf?)
03-21-2011, 05:39 PM   #73
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I agree, I hope in future firmware updates they allow a few more choices. I still do not see why we shouldn't be able to select anywhere from 1-7 FPS in at least .5 FPS stepings. Well maybe it will be something for their "to do" list...
03-21-2011, 06:20 PM   #74
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QuoteOriginally posted by Hound Tooth Quote
To be clear, I don't think this necessarily has anything to do with the camera's writing speed. I think what we're seeing is the image processing speed limit of the camera.
That can't be true, since the camera can process images (at 7fps) faster than it can write out - this is true for most cameras, where the camera can achieve a higher write speed in JPEG only compared to RAW, so the write speed is constrained by how fast the camera can write out the raw buffer.

In any case, the variance in write speeds between firmware revisions show that the current firmware is not at optimal writing speed (speculation about increased stability aside).

The actual write transfer speed is at 25 MB/s, which is driven off the HS clock rate at 50 MHz, so an effective write speed slower than 25 MB/s is a combination of card latency and wait time between blocks.

Since the K-5 runs a Fujitsu real time operating system, the slowdown in Firmware 1.03 could potentially be due to code changes that increase the wait time for some operations. As you say, potentially some of the code changes could be for increased stability, but equally it could be unintentional.

It may even be as simple as debug code left behind that could potentially be removed in the next firmware iteration. It depends on how serious Pentax engineers are about speed optimization - I suspect trying to fix the FF issue has probably taken up all their attention in this release.

Here's an idea for Pentax: release parts of the firmware into open source, and allow the wider community to hack it. Key routines that Pentax wants to keep away from their competitors can be in binary form only (encrypted if it's really critical).
03-21-2011, 06:50 PM   #75
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Just did a quick test, and can confirm the same card (Extreme Pro) inserted into my K10D resulted in an effective write rate of just over 18 MB/s (DNG).

Since we can assume the K10D has a slower processor than the K-5 (much slower fps, despite smaller image size) clearly the image processing speed is not a factor in the K-5 write performance.
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