Paul Coen wrote:
David Kilpatrick wrote:

accurate focusing and although the shooting speed is about the same
(2.8 frames per second or so, using either JPEG large fine or
RAW+JPEG) with a good card the A100 will shoot 9 or 10 continuous RAW
and - I have tested it.. - over 500 continous JPEGs in a burst! The 7D
will lock you out after a burst of only 3 RAW images or half a dozen
JPEGs. There's


Do you have the 1.1 firmware on the 7D? I'm getting significantly better
burst rates than that - at least double on RAW, more on JPEG. This is
with 1GB 80x Lexar WA CF cards, or a Sandisk Ultra 2 CF card of the same
size. I can do a couple of frames per second up to about 8 frames, and
it writes them out pretty quickly and I can start shooting again.

If I remember correctly, the image processing and the CF writes were
both improved in the updated firmware.


Yes, if you don't use continuous you can benefit from the fast buffer
write. I have the latest firmware and the 80X Lexar WA remains one of
the faster cards to use - it's what lives in my 7D. I have SanDisk
Extreme III and Ultra II cards but they don't offer any advantage. I
should have said continuous RAW+JPEG (though there does not seem to be
any penalty compared to RAW only) and that you don't necessarily get
locked out - just a delay - with a suitably fast card.

While the Sony A100 will shoot its recommended 6 RAW+JPEGs using the
MemoryStick Duo Pro adaptor and a Sony Pro card, put this adaptor in the
7D and the write speed is so slow it does lock you out. You can take a
couple of pix and then have to wait, almost like with the Dimage 7/A models.

One point about the Sony is that burst duration depends on the subject.
It uses raw file compression, and a simple subject (skier against sky
for example) can give you twice the number of continuous raw shots,
compared to a complex highly detailed one. You also get more shots and
faster shooting at ISO 100 (less noise) presumably because noisy images
are larger to compress. The 7D doesn't use RAW compression and is
unaffected by ISO choice or the type of subject.

David