Raw Files Bigger Than Expected: I just started using raw files (after years of jpegs). My Nikon D200 bodies are rated at 10.2 megapixels but I end up with files that are over 15.

WayneW Loc: South Carolina

I just started using raw files (after years of jpegs). My Nikon D200 bodies are rated at 10.2 megapixels but I end up with files that are over 15. What's up?

R.G. Loc: Scotland

if you ever find out I'd be interested to know. My P7700 has a 12MP sensor but the NRW files that it produces are up around the 25MB mark :? .

TommyMoe21 Loc: Bartlett, IL

MP is the sensor size. MB is the file size.

Brucej67 Loc: Cary, NC

Raw files contains all the unprocessed data while JPEG are processed and are much smaller.

WayneW wrote:

I just started using raw files (after years of jpegs). My Nikon D200 bodies are rated at 10.2 megapixels but I end up with files that are over 15. What's up?

oldtigger Loc: Roanoke Virginia-USA

R.G. wrote:

if you ever find out I'd be interested to know. My P7700 has a 12MP sensor but the NRW files that it produces are up around the 25MB mark :? .

The image file has to describe the color and illumination for each of those cells on your 12mpx sensor.
Instead of wondering why the file is 25mb you should be amazed it isn't 250mb.

wolfman

25 is nothing, mine are 45-50mb.

Armadillo Loc: Ventura, CA

WayneW wrote:

I just started using raw files (after years of jpegs). My Nikon D200 bodies are rated at 10.2 megapixels but I end up with files that are over 15. What's up?

WayneW,

You are looking at two different specifications.

Your camera has a sensor that is 10.2 Mpixels. This is the image capturing device, similar to film. You have 10.2 million photo sensitive transistors to capture 10.2 million photons.
After the sensor captures an image it saves the image as a RAW file that may be well over 10Mbytes, the electronic equivalent of the photons. If you save the RAW file to a JPG file the compression reduces the file size to something around 3 - 5 Mb.

Mpixels is the specification of the image sensor.
Mbytes is the electronic file size of the processed image file, and states how much data will be consumed in a storage device (hard drive).

Michael G

SonnyE Loc: Communist California, USA

In a nutshell...
From Nikon's site

For example:
My camera, a D3300, under the i button, image quality, lists the maximum file sizes of the different files I can choose.
RAW+jpg = 46 MB
RAW = 30MB
FINE (jpg) = 15MB
NORM (jpg) = 7.8MB
BASIC (jpg) = 4.8MB
(Sensor size is 24.2 Mega Pixels)

So as you can see, the files can vary in size considerably. And those are typically the largest they might be.
Mine have not been that big usually. But I don't pay that much attention to their actual sizes.
Mostly, I shoot in jpg fine. Because if it isn't right in the camera, it get tossed. And most of my shots are viewed electronically and not printed.
Also, I don't shoot for what it could be; I shoot for what it is and do minimal to zero post processing.

Also, I use the biggest SD card recommended by Nikon for my camera, and the fastest. In that I have found great happiness as the files (pictures) store very fast. Allowing me more flexability with my shooting choices.

R.G. Loc: Scotland

oldtigger wrote:

....Instead of wondering why the file is 25mb you should be amazed it isn't 250mb.

I'm curious as to why the MB count for my P7700 RAW files is more than twice the MP count of the sensor, whereas the MB count of my D5200 RAW files is only slightly more than the MP count of the sensor (24MP).

oldtigger Loc: Roanoke Virginia-USA

R.G. wrote:

I'm curious as to why the MB count for my P7700 RAW files is more than twice the MP count of the sensor, whereas the MB count of my D5200 RAW files is only slightly more than the MP count of the sensor (24MP).

p7700 is NRW RAW, D5200 is NEF RAW compressed?

R.G. Loc: Scotland

oldtigger wrote:

p7700 is NRW RAW, D5200 is NEF RAW compressed?

I was assuming that that's what made the difference, but more than double seems like quite a jump.

Does the D800 generate NRW files? If the MB count was more than twice the MP count, it would be quite a storage guzzler.

Armadillo Loc: Ventura, CA

R.G. wrote:

I'm curious as to why the MB count for my P7700 RAW files is more than twice the MP count of the sensor, whereas the MB count of my D5200 RAW files is only slightly more than the MP count of the sensor (24MP).

R.G.,

It is because you are mixing bytes with pixels, like Apples and Oranges. They do not make the same juice.

Michael G

oldtigger Loc: Roanoke Virginia-USA

R.G. wrote:

I was assuming that that's what made the difference, but more than double seems like quite a jump.

Does the D800 generate NRW files? If the MB count was more than twice the MP count, it would be quite a storage guzzler.

800/800E are NEF RAW

Leitz Loc: Solms

WayneW wrote:

I just started using raw files (after years of jpegs). My Nikon D200 bodies are rated at 10.2 megapixels but I end up with files that are over 15. What's up?

Your expectations are too low. Set your sights higher. :)

R.G. Loc: Scotland

Armadillo wrote:

....It is because you are mixing bytes with pixels, like Apples and Oranges. They do not make the same juice.

I know that there isn't a direct one-to-one relationship - it's the comparison between the two types of RAW that I find odd. NEF consistently generates RAW files that have a MB count only slightly higher than the MP count, whereas NRW results in more than a doubling.

I don't know enough about the different formats to even start speculating about the reasons for that. But I do know that uncompressed RAW is a lossless format, and I'm left wondering why NRW is so much less efficient than NEF. I don't even know if that is something that is unique to the P7700 and similar cameras, or is it true of all cameras that generate NRW files.