D200 question

[Jeff]

Hi all
I am lucky enough to get a D200 for Christmas. Seems like a great camera lots of settings to come to terms with but all good though.
One question images in Raw can be compressed(about 10mb size) or uncompressed(15mb),in viewing and printing is there much difference and what do you experts use.

Jeff

[adame]

Hi all
I am lucky enough to get a D200 for Christmas. Seems like a great camera lots of settings to come to terms with but all good though.
One question images in Raw can be compressed(about 10mb size) or uncompressed(15mb),in viewing and printing is there much difference and what do you experts use.

Jeff

Jeff ive never compressed the Raw images as im not really ever stuck for space im sure someone here has tried it

[radar]

Congrats on the new camera Jeff, you'll love it.

I was wondering about the same thing when I got my camera. Reading Thom Hogan's D200 ebook, he says that Nikon describes the NEF compressions as "virturally lossless" or "visually lossless".

It supposedly is in the highlight range that it starts to miss out on some of the data but our eyes don't really notice. He goes on to say that it will be noticable with heavy PP and various compression along the way.

If you have the space, keep it to full NEF, if you are tight on space, go for the compressed NEF, you may never notice the difference. Myself, I keep the full NEF, that way I know that I have the true "negative".

HTH,

André

[Gordon]

Enjoy your new toy Jeff!
I started using compressed NEFs on my D200 a few months ago as I was sometimes running out of space on my 2GB CF. I honestly cant notice any difference at all in the image quality, but I sure as hell notice the doubled capacity of my CF card!
I can fit about 250 images on it now, compared with the ~120 in uncompressed. The counter still shows that space is available for 120 when the CF is empty, but it only decreases at about 1 count per 2 new images.
The amount of space saving varies depending on how much detail is in the image.

Right now I'm waiting on an 8GB Sandisk CF... and hoping its not a fake card despite the low cost... the seller claims it is genuine.

[Onyx]

One of the supposed cons of the D70 was that it offerred only compressed NEF format. If the same compression algorithm was used in the D200 (plus white balance encryption which the orig D70 did not feature), it would be subject to the same supposed criticism, which was the rounding of values from the analogue to digital converter from 12 bits of data into a 'best fit' semi-logarhithmic function that's slightly under 10.5 bit total. ie. in theory you lose a bit of information in the highlights, which might be more difficult to recover in the compressed NEF file. I'm sure the exact mathematical function can be found with a quick google if you're really keen... Edit: I've found it explained somewhat in Thom Hogan's D70 guide on pg 96.

However, we all know that no digital camera can handle blown data well, and we should do all we can to avoid exposures from clipping...

Additionally, I have been amazed at the level of highlight recovery available on the D70 - dependent upon choice of raw converter; which I would imagine is likewise applicable to the D200's compressed NEF files.

[Jeff]

Thank you guys for all your help.

Jeff

[Matt. K]

I could never see the difference so I only shoot compressed RAW. If someone could post a couple of images that illustrate any difference then I'd be very interested.

[Onyx]

http://forums.dpreview.com/forums/readf ... angemode=1

Matt, someone has answered your prayers. TBH I didn't know it was such a huge difference in filesizes between the two. I shall commit to compressed NEF for 2007.

[Matt. K]

Thanks Chi! That was pretty well my understanding of the difference.

[Greg B]

Interesting. I hadn't tried compressed NEFs but now.....

It isn't only filesize on the card, it is transfers card to comp, and then of course storage on the HDD ( and archiving etc.)

Tom Hogan doesn't favour using compression, but he does tend to assess things at the limits.

A standard NEF is 15.8 Mb, Compressed ~8Mb

That is 1 gig (of those stupid 1000Mb gigs) saved space per 128 shots

It is a huge difference. I'm going to do some testing too, although with my slap happy standards, I'll prolly never notice any difference at ALL.

[gooseberry]

http://forums.dpreview.com/forums/readflat.asp?forum=1021&message=21444356&changemode=1

Matt, someone has answered your prayers. TBH I didn't know it was such a huge difference in filesizes between the two. I shall commit to compressed NEF for 2007.

The problem with that "test" is that he shot a totally blown specular highlight. I would like to see a test where there is detail in the highlights - would like to see if there is a larger difference then.

I suppose it won't be too noticeable unless you process the image a fair amount, you'll probably get posterisation then. (if you look at it, using NEF compression, you are basically using 9 bits instead of 12 bit, so you have only 512 levels instead of the 4096 - if you use jpeg you only have 256), so if you process it, like changing the curves etc, you may get posterisation.