RAW vs JPEG

FundyBrian

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Brian Townsend
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iPhone 8 Plus
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Since I mostly use RAW image format and RAW images require developing before they can be used, or even viewed at full resolution, it might be worth discussing what constitutes editing wrt. RAW images.
With a jpeg image the operating system applies some standard algorithms to enhance the appearance of jpeg images. Sharpening, noise reduction, white balance correction, contrast and saturation adjustments are all part of the standard algorithms.
Since a RAW image doesn’t have any adjustments made to it things like sharpening, noise reduction, etc are part of normal image development. Where is the line that divides regular development from editing?
 
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.

155483A7-67C9-4FB1-83AF-C8B66B422FC9.jpeg

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.

72A0A780-E046-4B68-AF4C-9D7AC35EB82F.jpeg

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.
269CF0BD-60EE-45F5-8011-25B53DF0BB56.jpeg

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.
 
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.

View attachment 148126
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.

View attachment 148125
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.
View attachment 148127
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.
I’ve avoided RAW partly because having to develop every image I take is frankly a pain but also because all the options available for RAW processing is rather daunting and I never seem to get the result I want. I know it’s all about practice and I have a niggle in the back of my mind that this is the way to go.

I am also painfully aware that I need to get stuck into learning a manual camera app so that it becomes second nature like the native app feels to me. However, none of them seem to do everything I want and I end up hopping from one to another without feeling competent in any. I think Camera2+ might be my final choice. I needed shutter priority when photographing vultures and this did quite a good job considering I wasn’t very proficient in getting the settings right.

I’m interested to see that you almost exclusively use Pureshot except for focus stacking when you use CameraPixels. I presume Pureshot can’t do Portrait mode? Does it work well with the Moment tele?
 
I’ve avoided RAW partly because having to develop every image I take is frankly a pain but also because all the options available for RAW processing is rather daunting and I never seem to get the result I want. I know it’s all about practice and I have a niggle in the back of my mind that this is the way to go.

I am also painfully aware that I need to get stuck into learning a manual camera app so that it becomes second nature like the native app feels to me. However, none of them seem to do everything I want and I end up hopping from one to another without feeling competent in any. I think Camera2+ might be my final choice. I needed shutter priority when photographing vultures and this did quite a good job considering I wasn’t very proficient in getting the settings right.

I’m interested to see that you almost exclusively use Pureshot except for focus stacking when you use CameraPixels. I presume Pureshot can’t do Portrait mode? Does it work well with the Moment tele?
As Brian has shown, it can take more than a bit of work to develop a raw image so that it improves on a straight-out-of-camera jpg. What I've settled on, for the moment, is using camera apps such as Camera+ and Chromatica that can save separate DNG and full-res/fully developed JPG images for each shot. That way, if the jpg looks fine, I can work from there. If there's a problem in the jpg -- blown highlights, oversharpening, too heavy noise reduction, etc. -- I can go to the DNG of the same image and try to work around those problems. (The DNG-only file has a low-res jpg preview, so it doesn't look that great unless you open it in an app that can handle raw.)

There are other camera apps, like ProCamera, that can save a high-res jpg combined with a raw DNG in one file. That file has a jpg extension and looks like a jpg to apps that don't understand DNG. Unfortunately, some apps that should handle DNG balk at these files. For example, Lightroom Mobile (my usual app for developing raw files) recognizes that these files contain a DNG but won't open them unless I upgrade to a subscription (no way). Raw Power, another raw developer, doesn't have any problem with the combined files, though.

Chromatica can also shoot Portrait mode (which it calls Depth mode), but with a quirk. To get a standard Portrait mode photo that Apple's Photos and other apps will recognize as such, you have to first review the photo in Chromatica and explicitly save it as a Portrait mode photo. If you don't do that, then the photo just appears in the Camera Roll as a regular image without the Portrait options.

One headache when working with raw is that the Camera Roll doesn't identify which images are DNGs and which aren't. (Grrr.)
 
As Brian has shown, it can take more than a bit of work to develop a raw image so that it improves on a straight-out-of-camera jpg. What I've settled on, for the moment, is using camera apps such as Camera+ and Chromatica that can save separate DNG and full-res/fully developed JPG images for each shot. That way, if the jpg looks fine, I can work from there. If there's a problem in the jpg -- blown highlights, oversharpening, too heavy noise reduction, etc. -- I can go to the DNG of the same image and try to work around those problems. (The DNG-only file has a low-res jpg preview, so it doesn't look that great unless you open it in an app that can handle raw.)

There are other camera apps, like ProCamera, that can save a high-res jpg combined with a raw DNG in one file. That file has a jpg extension and looks like a jpg to apps that don't understand DNG. Unfortunately, some apps that should handle DNG balk at these files. For example, Lightroom Mobile (my usual app for developing raw files) recognizes that these files contain a DNG but won't open them unless I upgrade to a subscription (no way). Raw Power, another raw developer, doesn't have any problem with the combined files, though.

Chromatica can also shoot Portrait mode (which it calls Depth mode), but with a quirk. To get a standard Portrait mode photo that Apple's Photos and other apps will recognize as such, you have to first review the photo in Chromatica and explicitly save it as a Portrait mode photo. If you don't do that, then the photo just appears in the Camera Roll as a regular image without the Portrait options.

One headache when working with raw is that the Camera Roll doesn't identify which images are DNGs and which aren't. (Grrr.)


terse & brian -

I occasionally PureShot . . .


regards,

jsi
 
I’ve moved this to a new thread, as the other thread is challenge specific. :thumbs:
Thank you for sorting this out. I really did want to participate but since I avoid shooting jpeg like the plague I didn’t have any images to contribute unless there was a way to use my RAW images. But using RAW images necessitates development and then the line of what constitutes development vs editing or enhancement becomes rather fuzzy.
 
I’ve avoided RAW partly because having to develop every image I take is frankly a pain but also because all the options available for RAW processing is rather daunting and I never seem to get the result I want. I know it’s all about practice and I have a niggle in the back of my mind that this is the way to go.

I am also painfully aware that I need to get stuck into learning a manual camera app so that it becomes second nature like the native app feels to me. However, none of them seem to do everything I want and I end up hopping from one to another without feeling competent in any. I think Camera2+ might be my final choice. I needed shutter priority when photographing vultures and this did quite a good job considering I wasn’t very proficient in getting the settings right.

I’m interested to see that you almost exclusively use Pureshot except for focus stacking when you use CameraPixels. I presume Pureshot can’t do Portrait mode? Does it work well with the Moment tele?
I’ve tried all sorts of RAW camera apps looking for the features I want. Whenever I run into limitations with other apps I return to PureShot and everything there works exactly as expected.

The way to get good quality results from an iPhone is to treat it like a “real” camera and to me that means RAW image format, like all my other cameras. To me using jpeg keeps you in toy camera mode. Great for casual snapshots but not for good image quality. I don’t always need the best quality so sometimes jpeg is fine but I know when I’m making that choice. For instance, there is no point in choosing RAW if I also plan on adding grunge effects later.

The main functions I like in PureShot that are hard to find in other apps are ISO Priority, and good white balance control, in particular being able to easily make a white balance reading from a white balance card. It could safely be said I’m an old school photographer. I believe in getting the image “right” in camera at the time of exposure such that corrections in post are not required.

In particular, when you are at the photo location is the only time you can tell what the real white balance is. In editing there is no reference and adjusting the white balance is just guessing. Certainly there are occasions when you want to alter the white balance from true for the sake of artistic expression, but even then it works better to start from an unbiased white balance point.

For photographers coming to the iPhone after using other camera types (DSLRs etc.) PureShot is the app that is most like a “real” camera. As soon as you look at it everything looks familiar and makes sense. It even has a mode dial just like a regular camera. You can set Shutter Speed priority with that dial for action shots. I mostly prefer the ISO Priority mode.

In the DSLR world, unless you are just a snapshot photographer virtually every serious photographer uses RAW format. The advantages are too great to ignore. And if you use RAW format then you soon enough get used to developing RAW files. The RAW controls are just the same as on the iPhone so it is a fairly universal experience. A good deal of the controls are the same as the familiar jpeg adjustments.

If you think you might want to go further at some time with your photography than the iPhone then PureShot is the training ground. Once you are used to PureShot you can pick up most cameras and make sense of everything on them.

Yes, PureShot handles any of the Moment lenses with no problems with the exception of the anamorphic lens used for video. The anamorphic lens requires a conversion phase to decompress it into a wider image. PureShot does not have any portrait mode. Maybe it will someday. However, there is no RAW in Portrait Mode.

If you look at the adjustments made to every jpeg image by the operating system the two most damaging to image quality are noise reduction and sharpening. Whenever the ISO gets high, as it often does on a mobile device, then a fair bit of noise reduction is required to deal with the image noise. Noise reduction could most simply be described as blurring the graininess to make it look smooth. Blurring equals loss of image detail.

However, if you deliberately use the lowest ISO then image noise is very low and doesn’t need any noise reduction in most cases, especially in regular daylight conditions.

Here is THE most important thing to understand about ISO in any camera. The camera sensor has a base ISO rating. It is usually the lowest ISO setting you can set on that camera. EVERY higher ISO setting you select is simply underexposing the image and then electronically boosting the image data by the same amount of underexposure. This electronic boosting doesn’t just boost the image data, it also amplifies any image noise in the system.

Let’s take a typical camera with a base ISO of 100. When you set 200 you are underexposing by 1 stop and electronically boosting by 1 stop. At 400 you are underexposing by 2 stops and boosting by 2 stops. At 1000, we’ll you get the idea.
The base ISO on an iPhone is 20 or 22 depending on the device. You can usually get away with ISO 40 or 60 but by 80 image noise is a real issue.

This means that for good image quality you want direct control over ISO. For anyone using RAW format choosing the lowest possible ISO is the best way to minimize image noise, thereby greatly reducing any need for noise reduction in development. I want to set the ISO to 20 and not have it change unless I do it manually.

Just about every iPhone app uses shutter speed priority and then adjusts the ISO for exposure. A lot of the time apps don’t even tell you what the ISO setting is.

PureShot has an ISO Priority mode and this is a very rare feature. I want ISO 20 and I generally don’t care much what the shutter speed is as long as it isn’t unreasonably low. In PureShot the camera settings are always visible onscreen so if I notice the shutter speed has gone too low I will raise the ISO until I get an acceptable shutter speed.

Gotta go now. More later.
 
Well this made me :lol: Brian !! In one sentence you've just trashed most of our images on Mobitog !!
I’m glad I was able to provide some entertainment.

But seriously, on any camera, using jpeg gives you about 70% of what you could have in RAW. If that is good enough for you, then fine. It’s just a personal choice and let’s face it using RAW on a phone is more work than most people want to be bothered with. Most photography enthusiasts want to maximize what they can get from their equipment.

Most of the time I think there is some potential for the pictures to find uses where the image quality is important, then RAW is the route.
Another factor is that some of the benefit of using RAW is diminished when using the reduced images sizes necessitated when posting to a site like MobiTog.

Something that greatly interests me is the type of image that can be greatly degraded 50 or even 80%, for instance with grunge effects or Hipstamatic, and they still hold up. You can make them blurry, wreck the colour, make them crooked, add scratches and textures, fog, whatever, but the underlying image is strong enough that people ignore the veil of destruction to appreciate the essential content of the image. In other words, all the effort to add effects is wasted because people look beyond it to the essential nature of the image.
On the other hand, when you have an image that relies on fine details for it to make sense it can easily be turned into meaningless muck by the same destruction bestowed upon the other image.
 
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