[derekkite]

I noticed this happening twice. When the sd card, a Lexar Platimun II 32gb gets over 500+ photos, raw format, the continuous shooting slows down by about half. I'll do a long sequence of continuous shots, filling the buffer until the camera slows down. I'll wait until it writes, then even a two or three shot sequence is slower after that.

I'm not certain the writing is slow, it feels almost like the buffer is smaller.

If I format the card, all is well.

Camera settings are constant. I get quite satisfactory continuous shooting speeds generally.

This on a K-5 with 1.11.

Forgot to mention. I got the card at London Drugs, a box store in Canada. I don't think it is counterfeit, been reliable otherwise.

[hcc]

In continuous shooting, your burst rate will slow down if:
- you have in-camera post-processing incl. lens distortion correction, high ISO correction, ....
- your buffer is full, or
- your card is too slow.

I do a lot of long hi continuous shooting, My experience suggest that:
- you must kill off all in-camera PP
- you must use JPEG for long sequence (simply because the buffer output rate cannot cope with RAW files at 5-7 fps (*)), and
- you must use a Class 10 card or faster.

Note: (*) A PF member measured the burst rate of the K-5 and find that it is often between 5 to 6 fps, shower than the official 7 fps. I measured myself the burst rate of the K-7 and I get between 5 to 5.2 fps.

From your description, I would say:
- you be better off to switch to JPEG for shooting continuously;
- get a fast SD card;
- after each sequence, wait until the shots are all written to the card and switch off any LCD preview.

Hope that the comments may help.

[Schraubstock]

Hi

Another possible reason for slowdowns:

When the card is full offload all pics to the computer after which you should FORMAT the card in-camera to make it ready for the next shoot.

Never selectively delete files, for example after you have taken a picture and you don't like it leave it on the card, because if you delete a lot of files that way your card will not be contiguous anymore. (Just like your hard drive in your computer) Read and write sequences will take longer and longer because empty spaces on the card are too fragmented. Also deleting, often if not always, leaves leftover bits behind.

So, never delete files off the card either in the computer or in-camera if you want to maximize read and writing speed. Always format and of course do this in-camera.

Greetings

[derekkite]

Both suggestions already implemented. Continuous shooting is fast and reliable until there are around 500 photos. Then it slows down by half.

I'll copy the images, reformat, and it works fine.

Looking at today's activity. I took 87 shots, outdoors cool weather starting at 3:33 till 4:00. At the end there were 531 images on the card, all raw dng. The first dozen were individual shots, then a burst of 14. 4 individual, then two bursts of 4. A dozen or so individual shots, some single shots repeated every couple of seconds. Then another burst of 8 or so. The camera was bogging down, about half the usual rate. The light stayed on for what seemed a long time and the camera was slow to respond.

The only other factor is that it was getting a bit dark. Sun sets at 5:36, and we are in a valley of deep shadow. I'm using manual focus lenses. Hmm. Something to do with focus confirmation?

[RonHendriks1966]

Maybe you are using AF-C mode, this slows things down (I think, but never put attention in meassurre it).

With RAW you can't keep shooting. A full buffer takes 32 seconds to empty, so the number of shots in one minute is down to a max of 50 shots.

[simico]

if you delete a lot of files that way your card will not be contiguous anymore. (Just like your hard drive in your computer) Read and write sequences will take longer and longer because empty spaces on the card are too fragmented.

I take it you have no idea how NAND memory and storage products (like SD cards) based on it work, and you've never heard of wear leveling.

[Michaelina2]

Do you have Focus Priority activated when in AF, C, Continuous Mode (K-5, Eng Manual, pp123)? This setting can slow things down as it requires the subject to be in focus before the shutter will fire.

My preference is "on" as I do not mind the trade-off of a slight slow down for almost always perfect focus.

Also, I've found that once your turn off all automatic in-camera image processing (it takes some deep digging into the Menus to make sure everything is off... Yes, even SR - I compensate by using shutter speeds above 1/500s which dampens blur from my movement and my subject's movement), things speed up considerably.

Cheers... M

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Last edited by Michaelina2; 11-02-2011 at 05:15 AM.

[derekkite]

Yes, it was set. So it was trying to find focus and having difficulty in low light.