fishnose said:
Note to Ron800: No, in FX mode you can never get more than 4fps. Regardless of grip/battery.
Oops, sorry. Edited my comment above.
D800 FPS hack?
(33 posts) (21 voices)-
Funny, my D4 at 8 FPS sounds a heck of a lot faster.... maybe the D4 has shorter seconds.... Actually in my test of listening to the video and timing, on about 10 trials the time for the "9 shots" was 1.3 seconds which comes out to less than 7 shots per second. Strange, a D300s does 7 FPS. A D300 does 6, or with the battery pack 7 on C,low, 8 on C,hi.
But the real issue is this. It is my experience one does not usually shoot a single second, but often will be shooting multiple bursts. Also, why does Nikon limit the frame rate unless one has the grip? Maybe it has to do with some other factor.
I find the video interesting, yet it would be my thinking to just shoot the camera at the 6 FPS rather than fiddle around to get some function the original design was not intended to do.
Of course, someone might say Nikon just wants to sell grips to make money, but I really doubt that is the whole story. Ah, the skeptic has spoken....
Posted 11 months ago # -
donaldejose said:
Oh, I wouldn't be quite so dismissive.Underlying this question is an assumption which I believe is valid: unlike the old 35mm film cameras which were mechanical devices the current DSLRs are more like computers in that they have hardware and software. If the FPS limit is a hardware limit it cannot be changed. If the FPS is a software limit it can be hacked. If the hardware can run at 5 FPS in DX it could also run at 5 FPS in FX. Most likely a software limit has been created so as to keep the buffer from filling up and disabling the camera while waiting to write to the CF card. Note this report of how many shots the buffer holds at various settings
"Shooting stills pictures in the FX format, recording NEF Raw files, at 14-bit and uncompressed, the camera generates a 74.4MB file, and the camera’s buffer memory has the capacity for 16 frames. Recording NEF Raw files, at 12-bit and lossless compressed the file size is reduced to approximately 32.4MB and the buffer capacity is increased to 21 frames. In the smaller DX format, when recording NEF Raw files, at 14-bit and uncompressed, the camera generates a 32.5MB file, and the camera’s buffer memory has the capacity for 25 frames. Recording NEF Raw files, at 12-bit and lossless compressed the file size is reduced to approximately 14.9MB and the buffer capacity is increased to 38 frames. While a JPEG file at the greatest resolution in the FX format produces a file of approximately 16.3MB, and 8.0MB in the DX format, with a buffer capacity of 56 and 100 frames, respectively."
http://www.pixiq.com/article/the-nikon-d800-official-announcement
I suspect the FPS limitation is not in the hardware but was deliberately set in the software to keep customers from complaining that their camera froze up after a few shots. If the buffer can only hold 16 RAW 14 bit files and you are shooting at 4 FPS your buffer will be full in 4 seconds. Lets use that 4 second buffer fill time as our goal. If the software allowed you to shoot at 6 FPS your buffer would be full in 2.6 seconds. Customers would feel the camera should shoot for more than 2.6 seconds before freezing up waiting for the buffer to clear. Hence the 4 FPS limit programmed into the software. Now just how fast would the hardware allow the D800 to run? Could it make 10 FPS, like the D4? We don't know. One would think the shutter and the autofocus could do it. One would think the real limit is file size. But, if you shoot JPEG 16 mb files and the buffer can hold 56 of those frames at 4 FPS you can now shoot for 14 seconds before the buffer is full. Well, why not have the option to shoot 8 FPS for 7 seconds in 16 mp JPEG format? See, it would be possible to shoot faster FPS and still not fill that buffer so quickly if you shot in a format which produced smaller files. Nikon chose to not give us that choice. Why? Because the camera is not physically able to perform it mechanically? Or because Nikon did not want to compete with the D4? Or because Nikon thought customers would not understand the higher FPS should only be used when shooting JPEG? Reasonable questions for which we will never get the answers!
I suspect the FPS limitation is controlled by the software and could be changed by "hacking." I am sure it could be pushed from 4 to 5 FPS in FX and most likely to 6, 7 or 8 FPS when shooting JPEG if someone "hacked" into the software. Most likely no one will do it because it won't be worth the time and effort required.
Interesting post. All images (RAW or JPEG) have to go through the ADCs and other hardware within the EXSPEED imaging processor on the camera .Some idea as to the throughput of EXSPEED 3 (quite crude I know):
The D800 can deal with 144MP/s effectively at FX mode (4fps/36.3MP) , and 91.8 MP/s in DX mode (6fps/15.3MP)
The D4 can handle about 162MP/s in FX (10 fps/16.2MP), and 79.2 Mp/s in DX mode (11 fps/7.2MP).Assuming the same throughput rate at FX and DX then the D800 should be theoretically capable of 10FPS @ 15.3MP. Wonder if it's the sensor which is limiting the frame rate?
Posted 11 months ago # -
OK, Throughput is a limiting factor. Does the D800 have a buffer before the Expeed processor? There is one after the Expeed processor. If the camera buffers then processes then buffers then writes to CF or SD card the processor throughput itself may not be the limiting factor. Just as CF or SD write speed is not a limiting factor because the buffer fills if the card is too slow.
Posted 11 months ago # -
It does have a 2MP 30FPS setting... :-P
Posted 5 months ago # -
I dont think nikon is doing it to sell grips. I believe that its to do with having to balance several factors especially the rigorous requirements of a Pro that needs reliability.
We all know that we can overclock our PC but in doing so it risks system failure in several ways.
1) overheating
2) Motherboard failure from brownout due to insufficient power supply wattage/voltage.
3) Other components not being able to keep up, like memory, video, hardisks, etc..
4) CPU failure. this will be due to sample variation... as they say YMMV.Having said that I have always over clocked my PC :-) but I then don't run Patient monitoring software or Air trafic control systems.
Also how many points of functionality do you need? and what are the compromises will you accept? I may like 20 FPS to shoot my baby first steps! So what if with that functionality the camera may fail after 50K shots? I will never reach that number. So why cant I have a camera with the 20FPS capability? just over clock the cpu already! give me a turbo button! LOL !
Or maybe give me the capability to have 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.7, 7.2, 7.7 FPS..
Posted 5 months ago # -
msmoto said:
Funny, my D4 at 8 FPS sounds a heck of a lot faster.... maybe the D4 has shorter seconds.... Actually in my test of listening to the video and timing, on about 10 trials the time for the "9 shots" was 1.3 seconds which comes out to less than 7 shots per second. Strange, a D300s does 7 FPS. A D300 does 6, or with the battery pack 7 on C,low, 8 on C,hi.But the real issue is this. It is my experience one does not usually shoot a single second, but often will be shooting multiple bursts. Also, why does Nikon limit the frame rate unless one has the grip? Maybe it has to do with some other factor.
I find the video interesting, yet it would be my thinking to just shoot the camera at the 6 FPS rather than fiddle around to get some function the original design was not intended to do.
Of course, someone might say Nikon just wants to sell grips to make money, but I really doubt that is the whole story. Ah, the skeptic has spoken....
The FPS limit without grips comes down to the batteries used. The EN-EL15 does not have the same voltage as the EN-EL18 or 8AA batteries (which are required in the D800 for faster FSP). The same issue arose with the D300, D300s and D700 with the EN-E3e without the grip, vs the EN-EL4a or AA batteries in the grip. The grip itself adds nothing, if all you put in is a EN-EL15 (or EN-EL3e).
You also notice that, with the right batteries in the grip, that shutter lag was reduced on the D300 and D700. It all comes down to the voltage of the batteries.
Posted 5 months ago # -
I think that if I had a D800, the last thing I would do is a hack to 'up' the FPS. You may find that there is a mechanical resonance that will destroy your mirror assembly or whatever - I don't like that 'cross your fingers and hope' approach - remember the six P's?
What I am saying is that a hackers skills are not in any way a replacement for an engineers!
Posted 5 months ago #
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