Thinking about how RAW images compare to jpeg images led me on an experiment to try to replicate as closely as possible what you see in the low resolution jpeg thumbnail that is attached to RAW images. The operating system cannot directly display RAW images in the camera roll so RAW images must have a low resolution thumbnail image attached to them so the operating system can display something other than a blank grey box for you RAW images.
For my example I chose a hand held photo I made recently. I was using my tripod and switching between my iPhone and another camera, but the tripod had the other camera on it at the moment and the legs were fully extended and when I came to this situation the sun had already risen above the hills so the only way I could exclude the sun was to crouch down low and since I knew it was going to take too long to rearrange my tripod for this low level viewpoint I made hand held pictures instead. If I was to stand up from my kneeling position the sun would pop out from behind the land to the right of the lighthouse and ruin the picture. I’m using just the middle exposure from a 3-shot HDR RAW image set made using PureShot.
Here’s the problem: when you select a RAW image to view in the camera roll what you see is just the low resolution jpeg preview, not the full size RAW image, because the operating system cannot directly display RAW images. So what you see is completely different from what the RAW image actually looks like. The jpeg preview receives all the usual heavy handed processing jpeg images always get in the attempt to give you the best image possible on your screen, at least they way they think it should look. That includes a fair bit sharpening and noise reduction as well as brightness, saturation and contrast adjustments. So the challenge is to figure out how to make the RAW image look as close as possible to the jpeg preview image.
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This first image is the jpeg preview image. And of course both images were resized to the standard MobiTog image upload size. I’m assuming for the sake of this test that if I had made jpeg photos this is what they would have looked like.
If you try to edit a RAW image in the Photos app as soon as you tap “edit” the image changes drastically from the jpeg view to the operating system’s edit of the RAW file. To save a version of the jpeg preview you have to open the picture in an app that does not edit RAW files and switches to editing the preview image instead. I this case I opened the image in Instaflash Pro and made no adjustments at all and just saved the jpeg preview image as a separate jpeg image.
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This is my developed RAW image trying to replicate what I could see in the jpeg preview image. The most obvious difference is that the preview image is lower resolution so the bars around the top of the lighthouse are less clear. I was developing the RAW image on my iPad while looking at the reference jpeg preview image on my iPhone so I could see both at once. I think I came pretty close to matching the jpeg image with the RAW.
This is what I had to do to make the RAW image look like the jpeg preview image:
Exposure, 0 adjustment
Black Point, -3, in other words I reduced the depth of the blacks a bit
Brightness, +20%
Contrast +6% , increase in contrast
Clarity 0, no change
Saturation +42%, a substantial saturation boost was required to match the jpeg image
Vibrance +23%
White balance, no change
Tint, no change
Shadows -7%, darkened the shadow areas a bit
Highlights -90%, reduced the brightness in the highlight areas a lot
Sharpening: Radius 21%, Amount 34%
Noise Reduction, Luminance, 31%, I wouldn’t normally use noise reduction at all since my ISO is usually 20.
I confess surprise at how much fiddling it took to try to match the jpeg image. I don’t normally ever refer to the jpeg preview images when editing RAW images and they just go where they go to satisfy my feel for the image.
So I hope you found this comparison interesting and/or instructive. I think it means that in terms of “no edits” some discussion would be worthwhile about RAW images.
A secondary point I would like to make is that the so-called unedited jpeg image has, in fact, received a heavy dose of edits without your input, before you even get a look at it. So the term “no-edits” takes on a different meaning since there is nothing you can do on a mobile phone to avoid the set of edits performed on your behalf, like it or not, that the operating system does to your images. If you want a truly unedited image the only way to get it is to use RAW image format.
Just for reference, this is what the undeveloped RAW image first looks like when opened in the RAW develop module of Affinity Photo - rather dull.
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The RAW image starts out looking pretty dull until it is developed. Yes, this is the same middle exposure from my HDR set but rest assured, all the image data is in there ready to be worked with.