Canon 40D shooting speed

[Greg D]

I have a 40D that shoots (as advertised) about 6 frames per second (shooting RAW).  It does not, however, do so for 17 frames (as claimed).  It will shoot 6 frames quickly then slow to about 1 -2 frames per second.  I had another 40D awhile back and I seem to remember that it would shoot about 12 frames without slowing before filling the buffer (which would be good enough for me).  There are two possibilities here:  1) My memory of my previous 40D is incorrect; or 2) There's something wrong with the one I have now.  I'm using the same 30 mb/s CF cards with this camera that I did with the previous one, so that's not a factor.  In both cases, my shooting parameters were similar - continuous hi drive, usually shutter-priority, auto ISO (or in bright conditions aperture priority and selected ISO), spot metering, center AF point.  So, questions for those of you still (or recently) shooting 40Ds are:  What sort of speeds are you getting, using what kind of cards?  Does the performance of mine seem normal?  Would a faster card make a significant difference?
Thanks much,
Greg

[DarkPenguin]

16 before it slowed...

[Ken Bennett]

I have two 40D bodies, and they both have a 6-frame raw buffer. That number is prominently displayed in the veiwfinder, and counts down to zero as I shoot. Using a Sandisk Ultra II card, I can shoot 7 frames very at full speed, then it slows to 1-2 frames per second. The small raw buffer was surely the result of Canon segmenting the market so pro photogs would buy the 1D Mark III instead.

I just tested with Large Fine jpegs and got the same result. Interesting.

[Greg D]

That's two very different results, like two different results from my cameras.  It would seem Canon has made two versions of the 40D and not told us??

[DarkPenguin]

That's two very different results, like two different results from my cameras.  It would seem Canon has made two versions of the 40D and not told us??

Lets just get the obvious out of the way.  You are set to the high speed mode and not the regular multishot mode, right?

[aduke]

That's two very different results, like two different results from my cameras.  It would seem Canon has made two versions of the 40D and not told us??

I've just run a series of experiments and found that it depends first on the quality setting. Raw shows 17 in the viewfinder while Raw + Large shows 13.

The actual number you can get at full speed depends on the ISO. Raw, at ISO 100, will shoot all 17 at the same speed. Raw + Large will begin to stumble towards the last ones.  

At ISO 1600, there is perceptible slowdown very early in the sequence.

Alan

[Ken Bennett]

I've just run a series of experiments and found that it depends first on the quality setting. Raw shows 17 in the viewfinder while Raw + Large shows 13.

OK, so this is really odd. Looking at the DPreview page, it claims the 40D has a 17-shot raw buffer. Their test page bears this out.

With both of my 40D bodies, setting them to RAW at ISO 100 I get a buffer of 6 frames. I am using Sandisk Ultra II cards -- not particularly fast, but they were when the cameras came out.

Any ideas?

EDIT: changing from raw to any jpeg size gives me the same maximum burst of 6 frames. Yikes.
EDIT 2: the user manual claims 17 raw files in a burst, and 75 large fine jpegs. I get 6 of either. Hmmm.

[Ken Bennett]

OK, a little digging and a random lucky read in the manual fixes this.

Go to Custom Function II-2, High ISO Speed Noise Reduction. Turn it Off (setting 0). This fixes the problem.

I just got 19 frames at 6 fps in a continuous burst of raw files.

--Ken

[DarkPenguin]

I've just run a series of experiments and found that it depends first on the quality setting. Raw shows 17 in the viewfinder while Raw + Large shows 13.

The actual number you can get at full speed depends on the ISO. Raw, at ISO 100, will shoot all 17 at the same speed. Raw + Large will begin to stumble towards the last ones.  

At ISO 1600, there is perceptible slowdown very early in the sequence.

Alan

I did my test at ISO 1600.  Is there a dark frame NR thing going on?

[DarkPenguin]

OK, a little digging and a random lucky read in the manual fixes this.

Go to Custom Function II-2, High ISO Speed Noise Reduction. Turn it Off (setting 0). This fixes the problem.

I just got 19 frames at 6 fps in a continuous burst of raw files.

--Ken

Of course you post this as I post my question...  Great catch.

[Greg D]

Lets just get the obvious out of the way.  You are set to the high speed mode and not the regular multishot mode, right?

Correct.

[Greg D]

OK, a little digging and a random lucky read in the manual fixes this.

Go to Custom Function II-2, High ISO Speed Noise Reduction. Turn it Off (setting 0). This fixes the problem.

I just got 19 frames at 6 fps in a continuous burst of raw files.

--Ken

Bingo! We have a winner!  Turned it off and now it shoots like a machine gun.  That wouldn't have occurred to me in a hundred years.  Thanks much!

Greg