kenadams: yes, the clattering noise I have heard from the D4 doing fast FPS seemed to me also to be indicating that mirror was slamming up and down to create the noise. I tried firing my D7000 at its highest FPS (about 6 FPS) and the mirror definitely returns. Don't know if it has to return at 16 FPS though. Could stay up and just let the shutter fire away. But your viewfinder would go black and you could no longer track the moving object you were trying to freeze so I suppose you have to have those momentary glances at your subject through the returned mirror in between each exposure.

My guess is that Nikon engineers parts to different performance specifications for each model and the mirror mechanism in the D800 may not be the same as the one in the D4 just as the shutter in the D800 is not engineered to the same specs as the shutter in the D4.

Donald, thx for the reply, pretty much, yeah, although I was asking myself specifically why the D800 at DX is slower than the D4 at 16MP FX; on paper, this should produce a comparable amount of data

1. the sound the D4 seems to make when shooting fast (unless artificially generated) makes me think the mirror comes down again; it's pretty loud; the speed involved here could be a factor, that's what I meant with "mechanics" and where the D4 and the D800 may be different

2. as the spec states, the D800 has a faster fps rate in DX mode, so some steps along the way must be performed quicker (possibly towards the end of the chain of events); however, what you're saying makes sense to me; in that case the chip itself and the still huge data would be the slowdown factor

kenadams: It would seem logical that the D4 processor can process half as much data (DX mode) twice as fast as it can process the full (FX data). Hence, your thought that a D$ should be able to have faster FPS in DX mode. Understandable logic.

However, I think there are two other factors.
1. The mirror has to move up and down which takes time and creates a physical time limt: unless the mirror stays up during the FPS.
2. I suspect every pixel on the FX chip actually is working every time an image is captured. DX mode doesn't "turn off" pixels. When the D4 is set to DX mode and a DX lens is used all of the pixels in an FX chip are still seeing and measuring light. The corners will be dark, but the FX chip is recording that data. The processor than has to take the FX recorded data and extract only the DX center portion of that data and send only that "cut out" image data to the memory card. Thus, when you switch to DX mode you are requiring the processor to perform an additional step in image processing: "cut out" the DX data from the full FX reported data. DX mode puts more work load on the processor than FX mode. That extra step takes time.

Does that help?

I dont think the limitations are technical. Any camera has to built to a budget, so I suspect the limitation is cost

Sevencrossing, I'm trying to understand where the technical limitations are, not why Nikon built it that way.

kenadams said:
I wonder why the D800 doesn't have a substantially higher frame rate

If it did, would anyone buy the D4

they also need some improvements to incorporate in the D800s

PB PM said:
I also doubt it is a mechanical issue, since it can shoot 6FPS in DX mode with the grip.

I wonder why the D800 doesn't have a substantially higher frame rate when shooting in DX mode, can anybody shed some light on this? It's roughly the same MP count as in the D4 shot in FX (~16MP, a bit lower even), same image processor too - so unless putting it in DX mode takes away a serious amount of processing time on-thy-fly, that leaves the built-in buffer, the energy source, the mechanics or the memory card in my opinion.

The buffer, when designed to be sufficient for images more than twice that size, should not be a bottleneck in this case. The fps specs make no distinction between memory cards and both have compact flash, so I figure it's not that either.

I'm not talking about what it should be able to manage or what is a feasible fps rate, just wondering where this discrepancy comes from?

I'm only really shooting on continuous with my D7000 shooting folk dancing stuff... I usually don't shoot until the buffer is full so I'm ready in case something unexpected is happening, and having been shooting photos with the same general group of people for a while I have a good idea of what the regulars are going to do and who to focus on at different times. Earlier on I was just shooting until the buffer filled up, then moving to a different spot, repeat, etc. There are times, especially with the 'better' dancers that are doing faster and more intricate stuff, it would be nice to have more than 6FPS and a larger buffer though.

bjrichus: I found I have to anticipate the shot and start the FPS just before the shot is taken to catch that ball coming out of the hands. If I wait until I see the shot actually taken the ball will quickly be out of the frame. 10 FPS and an even shorter shutter lag would be great. So I would love to have a D4, but cannot afford the price of admission.

donaldejose said:
I have been using the D7000 CL and CH modes to "machine gun" high school basketball in 4 or 5 shot bursts to try to capture that ball just after leaving the shooter's hands. Even at CH, which is about 6 FPS, that ball moves a significant distance between frames. I can see the use for about 10 FPS to catch "the decisive moment" in sports.

YES!!! Exactly my situation too. I just cannot get that moment on CH as that darn ball moves so much. It is one of the reasons why D7000's are not pro bodies and at work, why we fight to buy the faster bodies - but as it's the dear taxpayer footing the bill, we can't always buy what we want. At football (the American variety), I am able to get the ball on CH, as there is just a little bit more time there, but with soccer (the English football, you know, played with the feet... FOOTball? LOL!) it's often harder again. I'm just too slow or out of sync with the flow of play!!!

At least this years budget will see major changes to our camera body stock and we'll see what we get then.

I think I am learning way too much on this forum. Having found my way to a NIKON site which actually gives the file sizes required
http://imaging.nikon.com/lineup/dslr/d800/features04.htm
and http://imaging.nikon.com/lineup/dslr/d4/spec.htm
I have discovered way too much. On the D800, shooting TIFF(RGB) Large, the file size is 108.2 MB. On a D4, this would be a 49.1 MB File. If one shoots with NEF(RAW) Lossless, 12-bit, compressed, on a D800 the files can be "only" 32.4 MB, and on the D4 one has 15.4 MB files at this level. It is obvious to see the struggle with attempting to cram 108 MB files through a buffer. I suspect I will be shooting my D4 at the 12-bit RAW, compressed to keep files manageable.
Maybe the D900 will have the XQD slot. Or maybe Nikon is intentionally trying to separate the two into studio/action and will continue to make changes on the D800, 900, etc. line so as to bring it into the D4, et al, price range as time passes. This would make a very dominant position if NIKON could be considered as a studio camera with razor sharp quality and color depth.
And for an historical note, some of you have pulled slides... I used to do this with 11x14 Ektachrome... twenty - forty second exposures. So these new cameras are still very exciting to me.

donaldejose said:
If the processing chip inside the D800 ran more than twice as fast as the processor in the D4 and if the D800 had more than a two times larger buffer than the D4 they should be able to shoot the same FPS unless there is some difference in the mirror mechanisms used in the two bodies. I think it is likely just the same processor having to handle more than twice the data which causes fewer FPS.

A good rule of thumb is data is almost always exponential in growth. In digital you can't just double, you must quadruple.

Simple math as an example-
D4 10 frames = 16 + 16 + 16 + 16 + 16 + 16 + 16 + 16 + 16 + 16 = 160mb
D800 4 frames = 36 + 36 + 36 + 36 = 144mb + 36 = 180mb

So we can assume the processing with the buffer can handle somewhere between 140-180mb per second of processing and transferring of files.

I'm really surprised the D800 does not have the new XQD card slot. I'll take that to mean that the "hold up" is in the processing and not the buffer or the download bus for the D800.

sevencrossing said:
I have used double dark slides . . . so the concept of shooting at 4+ fps is a novel idea to me but I am getting used to it . . .

I've pulled a few dark slides in my time as well, but, I didn't realize it was my quote that began the thread, or I would've replied sooner! I don't shoot weddings, but have started to shoot entertainment-oriented, red carpet events. I think I said this in another thread, but this is a rather specialized type of shooting. 'A'-list celebrities will only make eye contact with your lens (if at all) for only the briefest of moments, so a high-FPS rate is essential for this type of assignment. For most other types of events, I would think 6FPS is enough. The 4FPS maximum rate of the D800 gives me pause, however.

sevencrossing said:
. . . and how you cope with flash, do you all use Quantum's

Yes, every photographer on the arrival line has either a Quantum Turbo, 2x2, or Lumidyne high-voltage battery pack powering their SB-800 or 580EX. You can buy them used on Ebay for $100 or less, and have them re-celled for only about $30 at a BatteriesPlus location (applies to Quantum Turbos only--not the 2x2s which are NiMH). Once re-celled, they perform like new. I own two Quantum Turbos: my first, I bought new, over 15 years ago, and recently had it re-celled (takes about five minutes). I bought another one used that came with a Qflash Model T that I got off Ebay, and had that one re-celled as well. Both perform like new.

I also doubt it is a mechanical issue, since it can shoot 6FPS in DX mode with the grip.

If the processing chip inside the D800 ran more than twice as fast as the processor in the D4 and if the D800 had more than a two times larger buffer than the D4 they should be able to shoot the same FPS unless there is some difference in the mirror mechanisms used in the two bodies. I think it is likely just the same processor having to handle more than twice the data which causes fewer FPS.

msmoto said:
For those of us who are still in the D90/D200, we have gotten used to 4 frames, then pause as the buffer clears, 4 frames, if one is lucky, but by then all the action is gone. The fps rate is not so much an issue as the total number of frames available. If a bike is going into a high speed shake and bake into a corner, one wants to be able to follow all the way into the sand trap and up into the air, into the sand, into the air, etc. Also, catching the rider where ever she or he may go... Then after maybe 20-40 frames, one can edit in the camera, as TaoTeJared says, dumping 90%, leaving five or six for final edit in the computer. and this is why a D4 will do what a D800 most likely will not, and it is a matter of file size into the card. I THINK?

Yes, that is what I do. With regards to the substantially reduced frame rate of the D800, I too presume that this is simply an issue of file size and nothing to do with mechanical differences. Am I right in thinking that there is no 'mechanical' reason why a D800 or D3x couldn't shoot at a much higher frame rate?

I will say the D90 has a faster fps than the D200 when the buffer is full...

I agree, msmoto. It's the eyes that make the shot and the lips that can ruin it. I have to get the shot where the eyes and lips are both perfect. Singers can get some pretty weird expressions with their lips when hitting the notes. They remind me of carp lips! lol

as for my approach, my shooting style is very similar to the one of skinbritt, prefer the reportage style on weddings, where occasionally I shoot in a series of max 10-15 images, usually w/o flash.
although in wildlife shot, it works a little bit different as I very often fire 15-20 images (especially when shooting birds), but I also delta them respectively leaving only with the one with good composition. with bigger animals, I'm trying not to exceed 5-7 images, as their speed is usually low.

Yup, and those eyeballs open and close as well! Sometimes out of four or five, the eyes are only perfect in one exposure and that is IT!

I like using the 4+ FPS when shooting certain concerts, I just don't like going through all of them choosing what to edit but the results are always worth the extra effort when I use it. I've got a concert this evening I'll be shooting multi frame. It's amazing how many times a singer's feature changes in one second.

For those of us who are still in the D90/D200, we have gotten used to 4 frames, then pause as the buffer clears, 4 frames, if one is lucky, but by then all the action is gone. The fps rate is not so much an issue as the total number of frames available. If a bike is going into a high speed shake and bake into a corner, one wants to be able to follow all the way into the sand trap and up into the air, into the sand, into the air, etc. Also, catching the rider where ever she or he may go... Then after maybe 20-40 frames, one can edit in the camera, as TaoTeJared says, dumping 90%, leaving five or six for final edit in the computer. In these cases, 6 or 8 fps is nice as things are moving very fast... like from 180 mph down to 20 mph in a few seconds. and this is why a D4 will do what a D800 most likely will not, and it is a matter of file size into the card. I THINK?

As to hammering in tent pegs, Look at the Photo-A Day and you will see one of my old cameras which may just have been used that way, ha, ha, ha!

PaulR said:
Buy a Nikon V1 and shoot at 60 FPS or video at 1200 FPS if want to slow things down

Anything is possible with a Nikon V1

I don't find that they are as good at hammering in tent pegs as a D3!

Buy a Nikon V1 and shoot at 60 FPS or video at 1200 FPS if want to slow things down

Anything is possible with a Nikon V1

I used bursts most when at an air show and at the zoo shooting big cats yawning. For the latter there's usually one frame in the bunch where they look misleadingly vicious. ;)