This subject is of interest to me as well. The histograms on the camera, which are rendered on the JPG file thumbnail, are usually substantially different than the Histogram when I import the RAW image into LR.
On the camera the pictures seem to be more middle of the histogram exposures. When I import them into LR, the histogram tends to be bunched to the right, even when I have made sure that I get no "blinkies" when taking the pictures.
>I know we are looking at JPG to judge Raw. > >So, after I disable all those settings... the JPG preview >should be nearly the same as the RAW image.
The JPG rendered on the rear LCD is compressed and displayed at a lower resolution and a lower bit depth than the unprocessed NEF you view later on your higher res laptop screen or desktop monitor. You'll never get the JPG to look the same as the NEF.
I think that Nikon and the other makers want the rear LCD on any DSLR to be used for guidance and estimation purposes. The LCDs seem too small for anything else, and don't have the res or the color depth for critical analysis.
I have a new image cataloging program (Expression Media 2), and a fundamental feature is the quality of the previews. They give us a choice of using the embedded thumbnail or generating one during import. As you might guess, one takes quite a lot longer than the other. So I wanted to see if the embedded preview has enough quality for the features of Expression Media 2.
Sat 19-Mar-11 12:44 PM | edited Sat 19-Mar-11 12:47 PM by elec164
> >Does anyone know what the actual pixel size of the generated >jpg preview is? >Also, if shooting raw only, is there a way to >"extract" it from the raw file?
If shooting raw only, the camera embeds a basic full sized JPEG. That image can be extracted using a program for doing so. But keep in mind the out of camera NEF embedded JPEG is only basic quality meaning it is highly compressed (a lot of lost tonal information).
Just do a search for JPEG extractor and you will find one. This Earthbound Light article provides a link to the one I have used.
Edited to add:
OPPS! Sorry Brian. From the time I started to reply there was no other response. But I was called away from the PC from time to time and when I finally got around to finishing up, I see you also responded.
You may find it easier to prepare an Apeture preset that closely resembles what you see on the LCD screen, including histograms.
The camera is rendering a jpeg image (embedded) from a raw data stream to provide an image for you to judge. You already know that. Aperture is going to do the same thing, but since all raw converters interpret or process the raw data slightly differently, and use all, some, or none of the camera settings, there is still no guarantee that the "raw" image pulled up in Aperture is going to match what you saw on the LCD. In both cases, you aren't really looking at raw data - you are looking at an image interpreted from the raw data. Even if you think you have everything turned off in the camera, both the camera and the converter are going to make some initial decisions for you in noise reduction, color rendering, sharpening, etc, to render an image.
I like Aperture as a converter. However, if I want to ensure that the image I pull up in my raw converter is going to match the image and histogram I saw on the LCD, I use Nikon View or Capture.