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sealhead
13-02-2014, 9:19pm
Hello,

Has any D800 owners noticed poor buffer performance? My new D800 only gives my about 7 to 8 continuous shots shooting in 14 bit raw before it fills up and stops shooting. My cards are fast so I'm putting it down to the camera buffer. NR is off. I don't want to resort to jpegs to get better performance if possible.

Regards, Tony

ameerat42
13-02-2014, 9:24pm
Have you checked out this (or similar) table?
http://www.dpreview.com/reviews/nikon-d800-d800e/14

Am.

sealhead
16-02-2014, 7:21am
Thank you Am, tested my 800 at home and it was within the table's range you sent so I'm thinking on the day I must have had something incorrectly for the buffer to fill so quickly.

Chookman
16-02-2014, 8:47pm
The D800e has a similar problem and would also cause the camera to lock-up
Buffering is no longer a problem but does still lock-up every now and then but nothing like before.

Chook

arthurking83
16-02-2014, 10:25pm
I'm sure I get about 16 continuous images at 14bit(bit rate actually makes little difference), with my fastest card(Lexar 800x) before the buffer fills and Ch slows down a bit.

Using my older not so fast fast cards from yesteryear tho .. Sandisk UltraII .. and you notice the difference .. about 5-10 or so frames before the card write slowdown begins.


Something to note too with settings.
Check Custom Setting Menu(CSM) d3(pencil icon)

d3 is the max continuous release setting. If this is set to a lower value than your cameras write capability, then you aren't making full use of the system bandwidth.

What this means.

(these are just randomly made up values!!)
lets just assume that your card is say 800x(or so) and can write at 40Mb/s.
and the buffer full capacity on the D800 is say (an example, not a tech spec!!) 1200Mb, and the camera can produce 4 images at 75Mb's every second.

So, in 4 seconds, the buffer is technically full, but as it writes and clears the buffer it has the ability to add more data again due to the cards write speed.

4 sec at 4fps = 16 frames. But this also assumes that the card can write a bit quickly too.

Even if your card writes speedily, if you have CSM item d3 set to 7 or 8, then the camera literally stops shooting quickly at 7 or 8 frames, and then slows down.

The reason I mention CSM d3 is because of your description:


...... before it fills up and stops shooting

This appears to be related to CSM d3 limited in some way.

if the camera was limited by a slow card write speed, you get a buffer filled up, but it doesn't stop shooting, it simply slows down to about 1fps after that point.


Rob Galbraith has a good card performance chart on his old site
(http://www.robgalbraith.com/camera_wb_multi_page89d8.html?cid=6007-12451&sort_col=raw&sort_dir=DESC)

of note is the buffer values he lists on the chart. I'm not sure of his methods, but those numbers look like just jpg numbers, not NEF+JPEG as he states.
I can't imagine a D800 shooting 30 raw files to the buffer full limit!

sealhead
20-02-2014, 10:43pm
Thanks Arthur, I have my max release set to 100 so that would not be an issue.
Sitting in the office at home I can squeeze out 16 frames on continuous high with no sign of it slowing or stalling. Must have had something set wrong on the day that caused the buffer or the card to choke. Buggered if I know what though. Will try to find the conditions that caused it report back to you.

Cheers, Tony

arthurking83
21-02-2014, 8:52am
Note too that IQ settings in camera can make a difference.
Think of the issue as a data bandwidth one, not a pure frame rate issue.

That is, how large are the files in Mb's. The more in camera processing(high ISO nr, active lighting settings, etc) you have set in camera, the larger the files.

An all black or white frame will have less data(Mb's) than a properly exposed scene(say a colourful landscape using grads and other filters that capture a huge range of colour/tones)
These aspects sould be considered in parallel to the topics of card speed, and write speed and buffer limits.