[dosdan]

Here are some measurements performed over 3 different sessions:

MF lens (to reduce focusing speed variations)
Continuous Shooting (Hi) operation
Transcend 8GB Class 10 class (unless noted)
PEF format (I don't shoot JPEG)
SR & levelling off
Firmware: 1.11

Speed can vary both in a burst (unexpected hesitation) and between bursts at the same settings. I've used a digital sound recorder to count the shots before large delays occur. I've also measured the time from the first to the last peak in this group to determine the average shot time & rate. (Using peaks means you don't have to worry about the problem of determining the exact start of a shot). All measurements were taken with both the camera and sound recorder on tripods, with the sound recorder situated on the left side of the camera (the right side has the battery bulge that probably shields the sound more) and a distance of 0.5m from the microphone to the lens mount centre.

Normally you'd be using large bursts when shooting sports/action. In the bright daytime, that's typically at a max. shutter speed of about 1/1000s.

1/1000s
25 shots were taken at a rate of 164 ms/shot (6.1 shots/s)
26th: 228 ms
27th: 1003 ms

1/100s
24 shots: 173ms/shot (5.8 shots/s)
25th: 991ms

1/4000s
26 shots: 164 ms/s (6.1 shots/s)
27th: 930 ms

I then switched to a 8GB Apacer Class 6 Card. Here is a comparison of the Write & Read speed as measured with a 7000 MB test file:

Transcend 8GB Class 10 - Write: 17.1 MB/s, Read: 21.4 MB/s
Apacer 8GB Class 6 - Write 8.5 MB/s, Read: 16.5 MB/s

There was no difference in the shooting rate at 1/1000s, but the effective burst length was reduced to about 24 shots. (I didn't look at recovery speed after the shot buffer was full as this was inconsistent.)

So, with PEF, the typical max. burst length at 1/1000s should be about 24-26 shots.

I then looked the typical & maximum acoustic peaks & RMS averages of these bursts. These are not A-weighted and this is a calibrated sound level meter, so use it as an indication of relative sound level in dB:

	1/100s	1/1000s	1/4000s
Max. Peak	-7.18	-7.1	-2.44
Typ. Peak	-9	-9	-3.5
Avg RMS	-29.17	-29.13	-27.6

You can see that using a high shutter speed increases the average sound level of the total burst by about 1.5 dB, but the typical peaks in the burst are 5.5 dB higher & the max. peak that occurred is about 4.6 dB higher.

Finally, a comparison of the K-5 & K20D shutter sound levels. Since there is some variation over the sound level of individual actuations, I looked at a number of these measurements. I think the typical difference is that the K-5 is about 3.2-3.5 dB quieter, with a different shutter noise frequency distribution (bassier & a little more midrange and less high frequencies). I'm not sure what the difference would be after A-weighting.

Survey of K-5 Continuous Shooting Speed
This table will be updated as submissions arrive

Raw, AF-C, Focus-Priority

User	Date of Manufacture (YMD)	Prod. ID	F/W	FPS
dosdan	2011-03-15	2	1.11	6.1
RonHendriks1966	2011-01-21		1.11	6.8

Dan.

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Last edited by dosdan; 10-22-2011 at 02:53 AM.

[hcc]

Dan
Nice tests. Hence your K-5 shot at about 6 fps, below its specs of 7 fps.

For info and comparison, I did some related test with the K-7 using JPEG (14 Mp [**]), MF at 1/50s all in-camera PP switched off. I found on average 5.2 fps over 30 s using a Sandisk Extreme III class 10 card.

[dosdan]

Dan
Hence your K-5 did not reach its specs of 7 fps.

I can't image how they can claim that figure. I just tried a burst of JPEG (*** Quality) and got 34 shots before the buffer choked, but the same shooting speed (6.1 shoots/sec).

Dan.

[RonHendriks1966]

Nice test. I think that with firmware 1.02 things changed. With the first firmware we had a small buffer buth in jpg we could make much more pictures (max of 273 in one minute) wich is now just a small amount more then with RAW (in one minute 104 jpg versus 99 RAW with fast PRO card).

I have no ideae wheater a faster card could give you just a little more or that there is no more juice in it?

From DPreview: although we have found that it wavers slightly, between 6.3-7fps tested with firmware 1.01

[RonHendriks1966]

Did you do a measurement in LiveView to see if this is different? It may be surprising, but never made measurements.

[dosdan]

Did you do a measurement in LiveView to see if this is different? It may be surprising, but never made measurements.

The only time I've ever used LV on a K20D or the K-5 is when doing moiré-pattern testing of AF accuracy, and that's because in that situation you're interested in seeing what's on the back LCD in real time.

If I was shooting macro more often I might be more interested.

Dan.

[rawr]

I wish camera makers included noise levels in dB in their normal spec sheets. Would be handy.

27-29db for the K-5 seems nice and quiet. A manually-focussed K-5 should be a very quiet camera indeed.

Any measurements for the K-x?

[dosdan]

I wish camera makers included noise levels in dB in their normal spec sheets. Would be handy.

27-29db for the K-5 seems nice and quiet. A manually-focussed K-5 should be a very quiet camera indeed.

Any measurements for the K-x?

The figures aren't taken with a calibrated SPL meter, so they're not relative to a 0 dBA SPL value. Just take them as a relative indicator.

Originally, I tried to do this in a field to get quasi-anechoic conditions (birds & there's still a sound bounce off the ground, but grass reduces MF & HF reflections), but it was too windy. I might try again on another day, perhaps pre-dawn.

Avg. RMS is probably not a good indicator of the perceived loudness - the longer the sampling period, the lower the average. But peak level probably isn't that useful either as it's of relatively short duration.

I think what's more representative of the perceived loudness of a single click is the energy of the click, so I might look at the Total RMS figure in a short sampling window around each click, perhaps a 50ms or 100ms sampling window. (I did try a 300ms sampling window, but I think that's far too long.)

I don't have a K-x, but I do have a K100D Super. But I think a K20D vs a K-5 comparison is sufficient.

Dan.

[RonHendriks1966]

I do see and hear that my K-5's (I own two, but I also used two others that I don't own anymore) have some variation in speed with Hi-speed continious shooting. Never paid attention to it in measurements. Sometimes it is anoying, but then again the next time it isn't, or I still have a dsecent shot and who cares about the rest.

So I did a little test for writespeed in my new K-5 black, because some-one was complaining about the speed of writing away a picture with his K-5 and a slow card. I use SanDisk Pro 45MB/s cards, so no problem here. The writespeed on average is around 18-19 MB/s for a bunch of RAW+jpg files.

Now it comes. I took the pictures of the clock on my PC:











So when this clock works and the timer is around the same when you see the second wiser with a shadow one then I'm counting 9 fps. Give or take one less. I'm not coming near 6,1 fps!

[RonHendriks1966]

Well made a video of it:

You Tube

You Tube

Turns out as 6.8 fps (thanks Dan for messuring!)

I did a few more bursts and it does vary a lot. I did have one other that looks more like 9 fps and others that are much closer to 6 fps.

It runs on firmware 1.11 and I use SanDisk PRO cards 45 MB/s and UHS-1 support wich is very responsive.

[dosdan]

I'm asking for submissions from K-5 owners to see how much the burst rate varies. PM or email me at dosdan @ gmail . com (remove spaces) and send me a MP3 of the sound of your burst or a link to a YouTube video of it if you're not comfortable with audio recording/separation. (240p is fine - it's only the audio I'm interested in.)

The settings should be raw, AF.C (I think the typical burst user would be shooting movement), no lens correction (don't think it affects raw speed anyway) & Focus Priority (C.3 - 16).

Also, if you don't already have it, please download PhotoMe.

PhotoME - Exif, IPTC & ICC Metadata Editor

Get the Beta version - the standard version has had no recent updates, and after installation do an update (Settings | Online Update) to get the latest Pentax Manufacturer notes (includes K-5), load a recent PEF file and include in your submission:

1. Firmware version - top right of screen.
2. From the Tag-ID 0215 (CameraInfo) section, tell me the Manufacture Date & Production ID.


I'll then publish a table of results.

Dan.

[Ex Finn.]

Your FPS measurements make for good read, how did you come up with the SPL readings, no lens just an open body or same lens on both bodies?. And if I missed it , my apologies in advance.
And just looked at my most recent burst of 10 shots, JPEG, highest quality, AFS, IS off, all processing off. SanDisk glass ten 16 gig.
Looks like it did it in one second. I am happy.
FW is 1.11.
MFG date 2011-03-22.
Service bit not set.
Product ID 2.
Cheers. Mike.

[dosdan]

how did you come up with the SPL readings, no lens just an open body or same lens on both bodies?. And if I missed it , my apologies in advance.

I looked at the peak height and also marked a selection (one peak to the next one) and then had Adobe Audition (a sound editor) perform a statistical analysis on the selected area. A Pentax M50/F1.7 lens was mounted and I was in M mode. Same lens used in all tests.

These are not SPL measurements. To do that I'd require a calibrated mic or a calibrated SPL meter. Rather, they are relative measurements.

So we can say that 29 dB is 50% louder than 23 dB. (6dB is approx. 1.5x as loud; 10 dB is 2x as loud - see Loudness volume sound level change factor of perceived loudness formula calculate power level noise levels volume logarithm dependence three four fold loudness sound - by what factor does level decrease dependence comparison decibel levels 3 dBSPL 6 ).

But we can't say that 29 dB here = 29 dB SPL which is is relative to a "0" sound pressure level of 20 µPa = 29 dBA SPL which has been A-weighted to more closely represent the audibility of the sound (the ear is not as sensitive to low level bass, and to a lesser extent, to high frequencies).

[dosdan]

I've inserted a table into the end of the first message in this thread and will update it as submissions come in.

Dan

[Gimbal]

The settings should be raw, AF.C (I think the typical burst user would be shooting movement)

Why AF.C paired with a manual focusing lens?