The compression is ‘lossless’ which means all of the original image data is usable by the photographer for subsequent editing. Nothing is discarded, even when the image processor compresses the raw file to make it smaller. Raw files contain the image data as it is captured by the camera’s sensor. Note how much more highlight and shadow detail can be extracted from this file. The lower image comes from a raw file recorded simultaneously with the JPEG. The enlargement on the right shows how both highlights and shadows have been ‘clipped’. The top image has been cropped from a high-resolution JPEG taken with a 16-megapixel Micro Four Thirds system camera. These images illustrate the main differences between JPEG and raw files. Each time a JPEG file is re-saved, more data will be lost and the discarded data can never be recovered. Photographers have some control over JPEG compression through the Image Quality setting.īut JPEG compression is always ‘lossy’. The processor then down-samples the image from 12 or 14 bits of information per pixel (as captured by the camera) to 8 bits (the default bit depth for JPEGs) and compresses it, discarding data that is unlikely to be missed by the human eye. These settings are locked into the image file. When recording a JPEG image, the camera’s microprocessor converts the raw image data into RGB pixel values (a process known as demosaicing) then applies white balance, saturation, sharpening and other adjustments according to pre-determined formulae. Advanced cameras let you choose the size and quality of the JPEG image so you can opt for the biggest and best JPEGs or the smallest JPEGs for online sharing and when storage space is limited. Sends him into a panic every time it happens, but he’s thankfull that I set up a workflow that means a hassle rather than a disaster.Photographers interested in printing their pictures will usually record raw files at the same time as the regular JPEG format, and most serious cameras include a RAW+JPEG setting for this purpose. If I hadn’t set LR to write XMPs he would have had to re-edit the whole shoot (remember, that’s 5k images!) and the job would have been late. Since I set LR to write XMP files and back up after each shot (day two shot three, etc) all I had to do was copy the photos to a new HD or grab the backup, make a new catalog and re-import the photos. Several times we’ve had drives go bad or disconnect during the editing process and it completely killed the LR catalog. When we get home from the shoot I set him up to edit, and he spends a full day editing and color correcting the shoot. If my photographer shoots 5k frames over three days with a crew of twenty and a budget of $125k I am going to do everything I can to make sure the data is safe. Once in a while I forget, since it isn’t on by default, and then have to go back and turn on the XMP setting. I make a new catalog for each job and always set the catalog preferences to write XMPs. Think about how much work is lost if a catalog goes corrupt and can’t be recovered! See ya!Īgain it comes up that Lightroom doesn’t write XMP files by deault.Īs a digital technician I can’t understand why. We’ll be back to normal next week with videos, and presets, and tips and all that fun stuff. I know it was a slow week here on the site but I had to jump in and teach a seminar for a co-worker this week and it kind of threw a wrench into my plans. XMP file because all of the changes are stored in your DNG file – not XMPs. PS: (you don’t see PS’s in blog posts often do you) It’s also worth noting that if you use the DNG format that this tip still applies but Lightroom won’t include a. Just grab both files and send ’em away and the recipient will be able to open your raw file with all of the changes. XMP file with the same name in the same place. Choose that option and Lightroom will put your raw file where ever you specify AND it’ll put a. But if you go to the File menu and choose Export you’ll get the export dialog and one of the export format options (in addition to JPEG, TIFF, and PSD) is Original File. You’re just getting the original unedited raw file. First, it’s worth mentioning that if you just find the original raw file that you worked with in Lightroom and just copy that file you’re not getting your Lightroom Develop changes with it – those are stored in Lightroom’s catalog. If you’ve ever wanted to take a raw file that you work with in Lightroom and send it to some one else to work with, but also include your changes to that file, here’s how.
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