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  # 1159703 22-Oct-2014 08:07
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You will have the answer in 2016




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  # 1159717 22-Oct-2014 08:34
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joker97: You will have the answer in 2016


Unless the answer is 42 - some clue as to what the question was may be helpful.

 
 
 
 


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  # 1159730 22-Oct-2014 08:48
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D810 is meant to be pretty awesome. If there are too many pixels to archive or process you can batch them to lower MP lossy DNG files, though I suggest making sure the white balance and exposure are in the right ballpark first as smaller dng renders some of those things and gives you less flexibility to adjust them later. Ideally do all your processing then convert.



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  # 1159736 22-Oct-2014 08:54
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I will indeed be binning most of the pixels and shooting in sRAW most of the time.

Unfortunately I had to buy what Nikon offer. They do not have what I want: the sensor from the D4s in a D800 series body. I'm not paying $8500 for a D4s, the D750 has unproven materials in the construction and the Df just isn't laid out right.

If you want a pro construction body you really only have two options now.

They have made some improvements that should aid getting sharp results hand held which was the bug bear of the earlier high mp cameras. It also has the Group Area AF setting from the D4s that will be very useful.

I actually wanted to switch to Sony but the A7 is not mature enough yet to rely on it for your living.





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  # 1159740 22-Oct-2014 09:00
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timmmay: D810 is meant to be pretty awesome. If there are too many pixels to archive or process you can batch them to lower MP lossy DNG files, though I suggest making sure the white balance and exposure are in the right ballpark first as smaller dng renders some of those things and gives you less flexibility to adjust them later. Ideally do all your processing then convert.

I agree.  The alternative Sraw option is not pixel-binned - I would avoid it.
The various crop modes may be useful at times.  Turn off AF-point illumination, and the entire cropped-off border becomes grey/blurred out - rather than a line.

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  # 1159744 22-Oct-2014 09:06
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Before you shoot sRaw to some testing head to head (ie one shot of a scene sRaw, one shot RAW) for a few varied scenes (maybe one with strong colors, one overexposed, one underexposed, one normal with skin tones) with full raw on adjustability in terms of exposure, color temp, etc. All sRaw files are a compromise and aren't quite full raw. I'd be interested to see the test shots if you can work out how to share 'em.

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  # 1159959 22-Oct-2014 13:17
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i never understand how sraw works. it's not an analog negative where lines are lines, rather a digital tri-colour pixel signal to noise data file that have some information removed!




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  # 1160124 22-Oct-2014 16:53
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joker97: i never understand how sraw works. it's not an analog negative where lines are lines, rather a digital tri-colour pixel signal to noise data file that have some information removed!


"Proper" sraw would pixel bin - average the value of the 4 red, 4 blue, and 8 green photosites to produce an unmosaiced raw file of 1/4 the dimensions of the original raw, with one red, one blue, and two green pixels.  As the photosite values are averaged, then the signal to noise ratio (from shot noise) remains unchanged.  For the Nikon D810, you'd get 9mp raw files (plenty for many purposes - even if half the linear resolution is lost) with very low noise.  But it's not so easy - as you'd certainly also get severe aliasing.  As far as I know the supposed "sraw" used by Canon and Nikon is already demosaiced, it has reduced bit depth in the case of Nikon's sraw, and because it's not "pixel-binned" but pixel / photosite data is dumped, then noise at the pixel level remains the same as it would have been for the full size image.  With sraw on a d810 you lose "about" two stops of dynamic range/high iso performance.  As mentioned above, downsampling and pixel-binning will result in aliasing, as will downsampling by dumping photosite data. So I have little doubt that as well as demosiacing the "real" raw data, it's interpolated / resampled on downsizing (adding "blur" to reduce aliasing) - which may give the appearance that noise isn't as bad as the 2 stops produced.  It's not raw, it's not useful in any practical way - it's a complete dog - a marketing gimmick from Nikon (Canon's implementation is slightly better).

If file size is an issue with the D810, the best solution is to buy bigger flash cards (it has dual CF/SD slots - so buy cheap high capacity SD cards - use a fast CF card for primary storage when speed is needed), use compressed raw, use lossy raw, use 12 bit compressed lossy raw if need be - as you'll still be losing a hell of a lot less than you would by using sraw. 


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  # 1160132 22-Oct-2014 17:07
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Large files still mean slower processing - on my i7 2600 with two SSDs D800 images were slower to load, slower to adjust, and slower to batch out, by 2-3 times usually.

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  # 1160134 22-Oct-2014 17:09
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is mRAW (around 8MP, from 23 MP) on my Canon 5d MIII any good?




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  # 1160141 22-Oct-2014 17:15
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joker97: is mRAW (around 8MP, from 23 MP) on my Canon 5d MIII any good?


I suspect it's better than Nikon's sraw, but it's still demosaiced, even if bit depth is enough to do exposure adjustments, white balance or other significant colour adjustments without too much loss (compared with the latitude offered by real full resolution raw).

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  # 1160143 22-Oct-2014 17:18
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I just realised, sometimes the file sizes were the same as a full RAW and I stopped using it. maybe it decides when to retain information and when to remove. who knows.




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  # 1160158 22-Oct-2014 17:25
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timmmay: Large files still mean slower processing - on my i7 2600 with two SSDs D800 images were slower to load, slower to adjust, and slower to batch out, by 2-3 times usually.


I can understand that from your perspective this would be an issue (wedding shots, many images to view/sort/post-process).
I don't have an issue with it being a bit slow - but for my uses.  For comparison, 36mp raw files on my core i7 render and edit at about the same speed as 12mp raw files did using the Core2 duo machine I was using when I had a D300.  Those 12mp raws were basically unworkable on the Athlon 2400xp machine I had in the spare room - but which handled 6mp raws from my Nikon D70.

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  # 1160163 22-Oct-2014 17:31
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Yeah 2000 images per day makes high megapixel cameras a bit of a pain.

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  # 1160169 22-Oct-2014 17:42
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joker97: I just realised, sometimes the file sizes were the same as a full RAW and I stopped using it. maybe it decides when to retain information and when to remove. who knows.


This is the crazy thing about "demosiaced" sraw.  Picture a "true" (unmosaiced) raw file, and each photosite come from under a bayer colour filter array - so the data recorded for each photosite only needs to carry one channel of colour information - consider it "greyscale".  The raw converter then converts data from each photosite, using mainly the green photosites to ascertain luminance data, calculate and apply an RGB value to every photosite.  Demosaiced - there needs to be a red green and blue value saved for every photosite.
So for a raw file, 36mp, uncompressed, 14 bit = 36 x 14 / 8 = 63mb (real raw files are larger than this - as there's metadata etc).
For a hypothetical "demosaiced" 36mp "raw file", uncompressed, 14 bit = 36 x 14 x 3 / 8 = 189mB - divide this by 4 for the small size version 1/2 resolution - and the file size is still 47mB.
Compression (lossless or lossy) is bound to work better on larger files (more redundant data).
What you report is no surprise.  From that POV (file size) Canon's "small raw" format is also a dog.

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