In part 1 of this series, I promised to show the tone curves for the various raw developers that I'm looking at. Here they are:


The Lightroom curves, for various settings of brightness and contrast - brightness has by far the most pronounced impact the image. In Lightroom, to get to a linear curve, you need to do three things - set brightness to zero, set contrast to zero, and select "Tone Curve - Flat" from the presets.


Then the Aperture curve showing the effect of the Aperture boost setting; the effect is essentially the same as the Lightroom brightness setting. To get a linear curve from Aperture, all you have to do is to set boost to zero.


Finally, the Capture One V4 setting; Capture One is a bit different to Lightroom and Aperture. Where Lightroom and Aperture have slider settings that are non-zero by default (brightness and boost respectively), on Capture One all settings default to zero. However, also by default, Capture One loads a "Film Standard" tone curve, which has a very similar effect to the other two program's non-zero settings. To get rid of the curve, all you need to do is to select the "Linear Response" Curve setting.


The last set of curves show a comparison of the default curve for each program, all referred back to a sRGB/2.2 gamma curve to make them comparable. While all the curves are about the same shape, there's a distinct difference in the "aggressiveness" of each curve. Lightroom/ACR adds the most brightness in the mid tones, and Capture One the least, and Aperture's about in the middle. We'll come back to this issue later in this series, but the next step is to use these tone curves to allow us to calibrate colors from the GretagMacbeth test chart.

And actually using the tone curves to calibrate colors is quite easy. All that's involved is the following two steps:
  1. Convert the l*a*b* color values for the GretagMacBeth patches to RGB in the color space of the program in question
  2. Use the tone curve to adjust the RGB values in accordance with the curve
Once we've done this, we have RGB values that are what should be displayed for each program, if the color calibration is correct. I've done this for the three programs I'm testing - a spreadsheet with the values is posted here: http://chromasoft.googlepages.com/calibrationspreadsheets.

In the next post in this series, I'll take a look at how each program compares.
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Good news in a difficult year - all the macOS apps that I support - AccuRaw EXR, AccuRaw Monochrome, pcdMagic, CornerFix, dcpTool (both the GUI and command line version), DNG cleaner and pcdtojpeg - now are all available with native Apple Silicon versions for blazing fast performance on Apple's new
There's a whole slew of new camera support, including for Canon's new CR3 format.

Updates of AccuRaw EXR, AccuRaw Monochrome, PhotoRaw are now available on the Apple App Store.
pcdMagic for Windows - the only currently available app that can convert Kodak Photo CD images with correct color and at full resolution - is now available on the Microsoft Windows Store.
As usual when new Leica cameras come out, I took a quick look inside a DNG from one of Leica's new Leica CL  cameras:

The camera name shows as "LEICA CL" The image data is 14-bit. There is no compression used in the DNG I looked at.  The DNG version is 1.4, with a "backward version" of 1.3.
Those of you that have read the Leica M10 raw file analysis post will know that M10 DNGs have more baggage in them that is typically the case for a Leica DNG. I've put together a little app to clean them up, called DNG Cleaner (Mac only for the moment).
AccuRaw users might have gotten a bit of a surprise recently - AccuRaw has turned into AccuRaw EXR, and is now at version 3.

The reason for the name change is that the focus of the AccuRaw product has changed a bit, based on what users were actually doing with it.
Good news - AccuRaw, AccuRaw Monochrome and PhotoRaw now have support for the compressed raw format that Fuji use in the new GFX 50S. Previous versions of AccuRaw/PhotoRaw had support for the regular uncompressed RAFs, but not the compressed version.
Updated: AccuRaw and PhotoRaw now have support for compressed and uncompressed RAFs.

For those that have been asking me about AccuRaw and Fuji GFX 50S support, I'm pleased to say that the version on the App Store as of today has support, although only for uncompressed RAFs.
As usual when new Leica cameras come out, I took a quick look inside some DNGs from one of Leica's new M10 cameras. Usually, there's not much to see with Leica DNGs - they are typically text-book vanilla DNGs. But with the Leica M10, things are bit more interesting.
AccuRaw EXR is a new version of AccuRaw with support for HDR (High Dynamic Range) images in OpenEXR format. OpenEXR is a high dynamic-range (HDR) image file format developed by Industrial Light & Magic for use in computer imaging applications that uses floating point data.
For those eagerly awaiting the opportunity to be able to process Olympus OM-D E-M1 II raws, the latest version (4.4.2) of PhotoRaw has support, including for the 80 megapixel raws. AccuRaw and AccuRaw Monochrome support will follow in a day or two in version 2.5.1.
New versions of PhotoRaw and AccuRaw became available on the App Store today with support for the new Canon EOS 5D Mark IV.

New to the Canon EOS 5D Mark IV is what Canon are calling ‘Dual Pixel Raw’.
Good news - AccuRaw, AccuRaw Monochrome and PhotoRaw now have support for the compressed raw format that Fuji use in the new X-Pro2. This is thanks to Alexey Danilchenko and the folks over at LibRaw, who reverse engineered the format, and published the results in open source form.
Yes, AccuRaw and PhotoRaw now supports the Nikon 5, all ISO 3,280,000 of it. The new versions are already available on the App Store.
LFI has recently published an article stating that the sensor in the new Leica M262 differs from that in the older Leica M240. This has generated a fair amount of comment on various forums because the M262 is, at least in principle, just a simplified version of the M240.
Mostly, I use this blog to write about photography related issues, but today I'm making an exception, and writing about email apps. Apologies to regular readers, but never fear, normal service will resumed soon.

Email is important to me.
CornerFix was one the the first imaging apps that I wrote. Written originally for the Leica M8 to fix the M8's "pink corners" problem, it corrects for vignetting, both in luminance and in color dependent form. In photographic circles, this is known as "flat fielding".
I've just found out that, to my regret, Photosmith has ceased development. In short, Photosmith allowed images to easily be uploaded to an iPad, sorted, rated, and the ratings etc transferred to Adobe's Lightroom.
(Edited 23 October to include information on how M lenses are handled.)

As usual when new Leica cameras come out, I took a quick look inside a DNG from one of Leica's new Leica SL (Typ 601) cameras, using one of the new Leica L mount lenses:

The camera is using what appears to be production softwa
Affinity Photo isn't one of my products, but I have been following it closely, and trying out the betas as they came out. It is now out of beta, and I know that a lot of readers of this blog are looking for alternatives to being forced onto the Creative Cloud model.
As usual when new Leica cameras come out, I took a quick look inside a DNG from one of Leica's new Leica M Monochrom (Type 246) cameras:

The camera is using what appears to be production software - version 1.0.0.4. The camera name shows as "LEICA M MONOCHROM (Typ 246)" The image data is 12-bit.
I don't often talk about pcdMagic because, well, there's seldom much new to say about it. For those that don't know, pcdMagic is my software package for converting old Kodak Photo CD images to modern formats.
PhotoRaw version 4.2.1 is now available on the Apple App Store with new camera support including the Sony A7 II (ICLE-7M2), Sony QX1 (ICLE-QX1), Panasonic DMC-CM1, Pentax K-S1, Olympus E-PL7, Fuji S1, Kodak C330, Leica D-Lux (Type 109), Leica V-Lux (Type 114), Samsung NX300M, Samsung NX3000
I previously wrote about a nasty bug in iOS 8 that prevented PhotoRaw from accessing any images that were shot as raw+JPEG.
While Adobe's DNK SDK has been a great asset for the imaging world, allowing all sorts of useful open source software, including my CornerFix and dcpTool packages, as written it only supports Windows and OS X.
So you can stop emailing me :)

The versions of AccuRaw and AccuRaw Monochrome on the App Store as of this morning (V2.2.8) have support for the Canon 7D Mark II, Canon SX60 HS, Canon G7 X and Fuji X100T.
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Author of AccuRaw, PhotoRaw, CornerFix, pcdMagic, pcdtojpeg, dcpTool, WinDat Opener and occasional photographer....
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