View Full Version : PP; Raw versus Jpeg


bestremera
08-10-2006, 04:24 AM
Currently researching RAW versus JPEG for post processing and seen some surprising results that claim that visually, manipulated JPEGS are surprising close in quality to files that start as RAW to say nothing of the excessive non-standardization of the RAW format.

I plan to do use a Nikon D50 a perform a fair amount of post processing Photoshop work with my photos from IR manipulation, b&W conversions and compositing.

Please advise on comparitive experiences with post process using JPEG and RAW.

Thanks all, Bob

Swampy
08-10-2006, 11:43 AM
I get a lot less luminance artifacting with RAW.

Hint.. use the DNG format. You can download the free RAW<->DNG converter from Adobe with built in auto naming and numbering as you offload your shots. You'll save about 1mb per shot storage space with no loss of information.

DannyRaphael
08-10-2006, 11:49 AM
Currently researching RAW versus JPEG for post processing and seen some surprising results that claim that visually, manipulated JPEGS are surprising close in quality to files that start as RAW to say nothing of the excessive non-standardization of the RAW format.

I plan to do use a Nikon D50 a perform a fair amount of post processing Photoshop work with my photos from IR manipulation, b&W conversions and compositing.

Please advise on comparitive experiences with post process using JPEG and RAW.

Thanks all, BobHi Bob:

I moved your thread to this forum since it is general in nature and will get more "looks" here than in the Photo-art forum.

Regarding your question, based on what I've read about RAW (I don't actually shoot RAW):
* The files can be a lot larger than .jpg = ramifications regarding disk space needed and time to batch process folders of files at a time
* One has ultimate control over correcting things like exposure and white balance, but WYSIWYG pretty much with sharpening -- just like .jpg. Seems this would have great appeal to those doing BW conversion, however I get good results doing 8-bit conversions of this nature.

If you haven't yet, try Googling something like:

"raw vs. jpg" -or-
"advantages of raw"

...for a boatload of other info and opinions on this topic.

~Danny~

mistermonday
08-10-2006, 01:40 PM
There are some major differences between RAW and JPG files and formats that are worthy of note.
RAW files contain raw data right off the camera's sensor. The settings you chose in your camera (like exposure, contrast, sharpening) are NOT applied until you import them through either the manufacturer's edit s/w or a converter like Adobe Camera Raw AND you have the option to change or nullify or accept those settings. In otherwords, you have the option to import the raw data into your image editor as the camera sensor detected it. It is usually in 12 bit to 16 bit data width per pixel.

On the other hand, an image which has been converted by the camera into JPG has already had all of those settings applied by the processor in the camera. These settings may be great BUT the camera may also have oversharpened, overboosted the saturation, made the image too contrasty, etc. Most of the damage in not easily undoable. JPG images are 8 bit max, therfore the extra data is thrown away and along with it goes subtle data which can not be recovered. JPG is also a lossy compression. Each time you save the image, you degrade it - only slightly if compression setting is high (12) and moreso as you lower the setting (increase the compression).

Making a curve or level adjustment to a 16 bit RAW file vs and 8 bit JPG file has major noticeable differences. Transitions in RAW are much smoother leaving fewer gaps in a typical histogram.

If you feel uncomfortable archiving files in proprietary RAW formats (I feel the same way), save archival copies as TIFF with lossless LZW compression as this is a universal format that has been around forever, or as .psd. If you decide to save as jpg for space considerations, use the highest settings (11 or 12).

Regards, Murray

Doug Nelson
08-10-2006, 04:41 PM
JPG and Raw are at opposite ends of the file spectrum. JPG is designed to provide the smallest file size possible, and does so by discarding data. Raw is the actual full data captured by the camera sensor. Nothing has been applied to it, or will ever be applied to it. No sharpening, no white balance, no color correction, nothing. However, all these things (and much more) can be applied while viewing, with all the settings data (amount of sharpening, exposure changes, etc.) stored in a separate file from the Raw file. So everything you do to a Raw file is completely non-destructive (even cropping, rotating, etc.). All that data will always be there, untouched, for you to rethink and reuse in the future.

gi1976
10-07-2006, 01:13 PM
RAW vs. JPG (http://digital-photography-school.com/blog/raw-vs-jpeg/)
:cat: