>> http://www.dpreview.com/news/0910/09102004lexar600xcf.asp

>>90 MB/second is "quite good".

> Hmm, what does that represent in '35mm frames/sec' ??? I guess it is that
> fast that it is sensor readout speed that will become the limiting factor.

My A700 does 5 fps.
D700 is about 7fps+
Very top 35mm is 11 fps I think.

File size depends on save format.

Raw compressed + fine JPEG <=~ 20 MB for me so that would almost stay
ahead of my camera.
Shooting JPEG extra fine only it would be much more than enough and
compressed raw only = enough.

For any 20+ MP FF DSLR you'd be getting under 5 frames per second.
Maybe about 2 fps for a Sony A900.
Which is silly.

Camera buffer size then becomes pivotal.
My 2003 KM 7Hi "prosumer" had almost 100 MB of internal buffer RAM
which was of extremely great use occasionally. In their later
notionally better but actually worse downgraded this to an unspecified
much smaller amount. Very naughty.

My A700 will take about 14 RAW photos continually before 'stuttering"
when using a 133X drive. Strangely, perhaps, it stutters sooner using
JPEG fine - possibly the JPEG rendering task and storage tasks compete
for overall resource. The RAW data could perhaps stram directly to
Flash if desired, with the data from a single image not having to be
in the memory at the same time, whereas the conversion to JPEG may
necessitate the storage of the whole image in RAM so that the JPEG
algorithm can process it. So - reasons unknown, but you need to know
what your camera will do to avoid bad surprises. At least film is a
bit more predictable :-).

One more nice touch - after itstarts stuttering with a fullish buffer
my A700 blanks the rear LCD and does not show an image again until the
CF write light extinguishes - typically about 5 seconds later.
HOWEVER, unlike some other cameras that I have owned, the camera will
still take pictures in this mode - you just have less secondary
information available. I imagine that the cemera is in 'shut down to
core faciklities' mode as it attempts to get the data stored and that
operating the LCD is not on its priority list. I also suspect that
this may have been a feault decision or even non decision along the
way and that nobody ever went back and revisited it.

I don't know how much CF write speed would influence the blackout time
or where the camera write speed becomes the limit. I have known this
for other of my cameras but there is a vast amount to learn amidst
actually taking photos.


       Russell
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