What exactly is RAW processing and.....

PSK said:

....should I look for a program with great RAW processing or one with great editing capabilities or separate ones for each task?

I have used Photoshop and Lightroom and am trying to get up to speed on Affinity Photo 1.5 for Windows. I have used Photoshop to adjust colours, change exposures, repair blemishes, etc. and am quite comfortable with that program. I've read that Capture One does a great job of processing RAW files. Does that mean that it is great at converting RAW files to other formats for further editing? Would the ideal combination be the "best" RAW conversion software combined with the "best" image editing software?

This newbie is confused!

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I respectfully suggest that you also consider workflow and learning curve.

You're already familiar with and use 2 Adobe products both of which have a very good raw processor included. Try out ACR (no need to purchase anything) and see if it fits your workflow and you can obtain desired results.

PSK said:

My response would be that I would want the best results, assuming that I was equally proficient in all of the software packages.

Also, I would compare BMWs to Mercedes..........

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You are trying to quantify "best" in what is, at its core, an art. Beauty is in the eye of the beholder. What one thinks is best, another will think is awful. We've been known to ADD grain or noise to an image, for artistic reasons. Some think that HDR looks real, while others think it looks garish.

Take BMW and Mercedes as an example. They manufacture competing models that essentially perform the same. They might make slightly different compromises in the final products. Materials are all top notch. Aesthetics can be different. Do you prefer walnut or carbon fiber? They both cost about the same. Do you prefer a 4-door or 5-door? Do you prefer a diesel or petrol power plant? Do you prefer a DCT or traditional TC tranny? Do you prefer more sport and less luxury or vice-versa? These are all emotional, subjective differences, not objective, though many try to objectify them.

You're trying to quantify human emotions. That doesn't work. I use both Capture One and Lightroom. The only difference in the final images is in the original files. CO gets my medium format workflow and LR gets my DSLR workflow. Why? Subjectively, I like the way CO works with "MF" and LR deals with "35mm". After all, CO was originally intended for distribution and compatibility with Phase One backs. LR was primarily developed from the ground up for use with DSLRs. If I edited identical Canon CR2s with both CO and LR, you wouldn't be able to tell which came from which. CO and LR are both tools I use to create MY vision. And that's, ultimately, what you see, my vision.

I'm not sure why we're discussing the "best quality" in photography. Are you shooting a $100k+ Hasselblad system? Everything in life is a compromise, especially art, even if photography has more or less been commoditized.

PSK said:

OK then. Dumb question #2. What does RAW processing entail? Is it the quality of the conversion to lossless formats, or is it the ability to manipulate the raw image prior to converting it to another format?

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I'd say it's more in the ability to manipulate the raw data to suit the photographer, and how much the RAW processor can do to make that manipulation easier for the user.

For example, some RAW processors have the ability to correct lens distortions and aberrations automatically for specific lenses they support; such things can be difficult and time-consuming to correct by hand.

Some photographers want the RAW processor to manage and organize their image files; others don't.

Trial a few RAW processors, then you'll have a better idea of how you want yours to work. Pick the one that does the most of what you want, and that annoys you the least.

The easiest and best for processing RAW is Bridge/ACR/Photoshop. It has all kinds of features for culling and very fast too for processing RAW.

"If I edited identical Canon CR2s with both CO and LR, you wouldn't be able to tell which came from which"



That's essentially what I wanted to know.

Raw processing is mathematically rendering or constructing an image relevant to human vision using a mathematical model.

Raw data is a spatial array of whole numbers that represent red, blue and green light amplitudes. This is the minimum amount of information required to compute an image to model the scene we photographed.

The information in a raw file is discreet. However our visual perception is a continuous, or analog, phenomenon. So the challenge is to reconstruct an image we perceive as continuous from discreet data.

The data alone is useless. A model is required to convert discreet data into continuous information content, or knowledge. The knowledge we need consists of the spatial distribution of light amplitudes, color hues and tonality (the range and gradients in light intensities).

With very few exceptions the Bayer filter is the model used to render discreet data into continuous knowledge. The success of Bayer filtering is a result of the very high degree of correlation between data and the model. The red, blue green color-filter array insures the data maps directly onto the Bayer image reconstruction model.

The mathematical models used for raw processing involve linear interpolation algorithms. The conversion process is called demosaicing. There are many different successful demoasicing algorithms. But all of them make use of the well-defined and high degree of correlation between the red, blue and green images in the raw data.

The parameters used in demosaicing interpolation algorithms change for camera to camera because the cameras' color-filter array characteristics are not identical. Further customization is can be achieved by adjustments to the algorithm parameters.

After an image is reconstructed, selective changes in the RGB components can be made to optimize the image's aesthetics. This is not demosaicing.

All digital photographs are rendered from raw data. In-camera raw rendering uses proprietary demosaicing to create JPEG images. We can choose in-camera parameters to modify a reconstructed image's aesthetics. Post-production rendering is similar.

Each camera brand has complete knowledge of their cameras' color-filter array characteristics. They use this information to offer the optimum, in-camera image reconstruction for each camera model.

Post-production raw rendering software vendors use different proprietary demosaicing strategies. They reverse engineer the characteristics of each camera's color-filter array. These differences along with differences in the user interface and intended rendering workflows explain how come the wide diversity of opinions and preferences for digital image rendering platforms.

Since a raw file contains all of the data, the aesthetic rendering possibilities are unlimited. By contrast, rendering a JPEG irreversibly removes much of the original data. However in-camera JPEGs provide a significant advantage. They use the camera designers demosaicing and are more convenient.

There is no single answer to raw vs. JPEG discussions. Well-informed photographers will choose what best suites their needs.

PSK said:

"If I edited identical Canon CR2s with both CO and LR, you wouldn't be able to tell which came from which"

That's essentially what I wanted to know.

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Demosaicing a Bayer pattern sensor is no mystery. If you want to know how it is done, you can read open source software such as dcraw. I'll point you to the relevant files if you have any interest.

It has essentially come down to why some publications (such as NPhoto) review programs and claim that those programs' RAW processors are the "best". NPhoto reviewed Capture One, ACR and others and their conclusion was that Capture One had, by far, the best RAW processing engine. I am simply trying to figure out what one processor can do that another cannot, or whether the results from one processor are superior to the results from another. Are they saying that Capture One produces better results when using the same controls (contrast, lighten, shadow reveals, etc.) as ACR and others?

PSK said:

It has essentially come down to why some publications (such as NPhoto) review programs and claim that those programs' RAW processors are the "best". NPhoto reviewed Capture One, ACR and others and their conclusion was that Capture One had, by far, the best RAW processing engine. I am simply trying to figure out what one processor can do that another cannot, or whether the results from one processor are superior to the results from another. Are they saying that Capture One produces better results when using the same controls (contrast, lighten, shadow reveals, etc.) as ACR and others?

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I'm not in the UK and have never read nPhoto, nor visited their website, until now. Offhand I would not rule out payola in this case.

One way to compare Raw converters is to accept all the defaults and see what happens. But all or most Raw converters produce improved results with extra effort. Except for images with wide dynamic range, I usually prefer out-of-camera JPEG in the Dpreview galleries.

Lately I've been reading the Fuji X forum. It is very evident that Lightroom/ACR is the worst raw converter for X-Trans color array, especially when sharpening is set even moderately high. Many folks continue to use it however, because they appreciate the workflow. Capture One produces a very nice sparkle that I could not reproduce with RawTherapee. So for Fuji X-Trans, I would say Capture One is superior to Adobe. Many Fuji X owners say that X-Transformer, a Windows subset of Mac-only Iridient, is even better when used as a preprocessor to Lightroom. Not convenient however - you must save DNG files in addition to the original Raw. Space wastage! Some say that RawTherapee has an equally good X-Trans demosaicing algorithm.

I don't follow Raw conversion of Bayer pattern sensors, so that's the limit of my knowledge.

PSK said:

It has essentially come down to why some publications (such as NPhoto) review programs and claim that those programs' RAW processors are the "best". NPhoto reviewed Capture One, ACR and others and their conclusion was that Capture One had, by far, the best RAW processing engine. I am simply trying to figure out what one processor can do that another cannot, or whether the results from one processor are superior to the results from another. Are they saying that Capture One produces better results when using the same controls (contrast, lighten, shadow reveals, etc.) as ACR and others?

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They can say whatever they like. Whether it has any reality for others is another question, for which the answer is IMO likely no.

There are differences in RAW processor features, but I've never seen convincing evidence that any of the most popular ones are capable of consistently superior output over a wide range of images.

A poll was taken here about RAW processor preferences; I don't have a link to it, but I did find a snapshot of the results at one point in time:



Does this mean ACR/LR is the best RAW processor? No, it means it's the most popular. Adobe products in general have a huge market share.

No need to agonize about this decision; I don't think any of the top three RAW processors is terribly hard to learn, and much user knowledge is applicable to all of them.

I guess that a way for me to determine whether there are differences in processors is to generate lossless images from each of the highest rated ones without any enhancements and then compare. Conversely, some of the processors may do better jobs at highlighting, bringing out shadows, producing sharper images when their individual tools are used. Getting my hands on each of them may be a whole different problem though!

Someone suggested that all of the processors will do good jobs and that it wil come down to my personal preference. Unfortunately, I can get obsessed with analysis and usually try to find the "best" of anything I purchase, however subjective that may be and however long it may take to get to a final decision.

PSK said:

I guess that a way for me to determine whether there are differences in processors is to generate lossless images from each of the highest rated ones without any enhancements and then compare.

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Might be better to work with their adjustments and see how close you can get to what you think is ideal. Then generate the TIFFs and compare.

Also consider how much effort it was to make the necessary adjustments. You may be doing a lot of that over time.

PSK said:

Conversely, some of the processors may do better jobs at highlighting, bringing out shadows, producing sharper images when their individual tools are used. Getting my hands on each of them may be a whole different problem though!

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The last I heard, LR, DxO, and CO all have free trials to download.

PSK said:

Someone suggested that all of the processors will do good jobs and that it wil come down to my personal preference. Unfortunately, I can get obsessed with analysis and usually try to find the "best" of anything I purchase, however subjective that may be and however long it may take to get to a final decision.

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You won't know what's best for you until you try them all extensively, but that's the safest way to decide, especially since you're not in a hurry.

Thanks to everyone for their valuable input!

Now I just need to buy a camera.................(just kidding).

I would say there is no generally best RAW conversion program.

The RAW format is indeed is some representation of data captured by sensor. The information is very LOSSY. This is because of bayer filter before the sensor. You don't have complete color information for each pixel.

So essentially RAW conversion program has to fill the info somewhat, interpolate the values nearby. This is demosaicing. As you can think this will make problems in some scenarios, edges.

Therefore there is a lot of different approaches and algorithms.

E.g. in RAW conversion program darktable, you can choose from various algorithms, you can see what it does and compare which suits your photo best.

Of course there are also other things which modern RAW conversion programs do, but demosaicing is the essential one.

PSK said:

....should I look for a program with great RAW processing or one with great editing capabilities or separate ones for each task?

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This really is a matter of habit or taste if you will. I prefer to use separate programs for separate tasks so I can choose whatever works best for me, for my images and my personal kind of processing preferences.

I also do not want to be tied down if some other software appears that does one of those tasks better than what I normally use, I want to be able to select whatever works best at any given moment in time.

As an example on raw conversion, for many years I used UFRaw in a scripted 16-bit workflow until Darktable came of age. I slowly moved to Darktable which is now my goto raw converter. DT doesn't handle Pentax's pixelshift files though so for that I've started using RawTherapee in parallel. Great editing is the one thing I'm not looking for in either, I'll use Digikam/Showfoto or Gimp 2.9.5 for 16-bit editing simply because they offer a better editing toolkit (better for me, that is).

PSK said:

I have used Photoshop and Lightroom and am trying to get up to speed on Affinity Photo 1.5 for Windows. I have used Photoshop to adjust colours, change exposures, repair blemishes, etc. and am quite comfortable with that program. I've read that Capture One does a great job of processing RAW files. Does that mean that it is great at converting RAW files to other formats for further editing? Would the ideal combination be the "best" RAW conversion software combined with the "best" image editing software?

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If you are comfortable with a split workflow I do believe your last statement is correct. Photoshop is of course an industry standard for editing offering an ultra wide range of tools, scripts and plugins as well as infinite ways of pixel manipulation and layer handling - PS certainly is the bees knees in editing.

The same cannot be said for raw conversion with ACR in either PS or LR. The Adobe-standard raw conversion is severely limited to- and handicapped by- one single (almost antiquated) debayer algorithm, coupled with some heavy-handed (almost scripted) sliders which make you forget about the details of pixel and colour manipulation at a pixel- as well as wider-area level in the image.

It may certainly be to the liking of a large group of people but it has never seemed like a good idea to lock yourself in with one single solution provider, whether paid of free.

Thanks to everyone for your comments and contributions!