Sunday, October 12, 2014

Just an excuse

Having just purchased a pretty good laptop, this weekend I wanted to get all my photography-based software up and running on it.

As I mentioned in an earlier post, I intend to keep the laptop highly biased towards photography, ie I will not overload it with ‘non-photography’ software. Having said that, I think most of us make use of Microsoft Office, but is it an essential piece of software? Having done some research, rather than load up Office, I decided to opt for the WPS suite, that seems to give me the equivalent of Word, Excel and Powerpoint, but for free: This is my first post written in WPS Writer.

In addition to proving out my laptop blogging workflow in this post, I will, hopefully, also answer a Magic Lantern question that some have posed, namely: “ Dual-ISO really worth the bother?”

As a reminder, there are two ML ‘functions’ that make photography on EOS cameras standout from others. The first is a RAW-based Auto Expose To The Right (A-ETTR) exposure setting function. The other, which I believe fits seamless with the A-ETTR function, is Dual-ISO.

As I have posted about these two functions previously, I will not reiterate the basics again. Suffice to say, using an A-ETTR+Dual-ISO workflow will get you the best exposure for post-processing, ie tonal data distribution and dynamic range, ie nearly 15Ev.

So, for the skeptics, and you know who you are, here is what an A-ETTR+Dual-ISO photo shoot looks like. I have chosen the image not because of its composition beauty, but because of the initial shock value of seeing the out of camera RAW in Lightroom.

So here is what LR first presents you with. I have included the LR histogram to further illustrate that, initially, you may think all is lost with this image. The image (screen capture) looks extremely blown out and the LR histogram, pushed all the way to the right, only confirms our worst fears, ie this image is not worth working on.


To the uninitiated, zooming in further confirms our fears, as the image is ‘obviously’ corrupted; as this LR screen image shows. Afterall look at those horrible lines running through the image.

In case you are not aware, what we are actually looking at, in a single image, is in fact two images: one catured at ISO 100 and the other at ISO 800. The lines are the alternating sensor data at those two ISOs.

As I trust the A-ETTR+ Dual-ISO workflow, seeing such an image is of no concern to me, as I know the Dual-ISO plugin ( will process the RAW .CR2 data into a secondary (DNG) negative. The resultant (secondary) DNG negative looks like this before any LR or Photoshop tweaks. Look at the histogram, it is now looking like a perfectly captured ETTR image.

And here is the image after a few basic LR tweaks, including some sharpening.

Bottom line: I maintain that for Canon EOS shooters, the combination of Auto-ETTR and Dual-ISO represents one of the best DSLR enhancements for data capture. This combination of unique (ML) tools provides an 'optimum' data set from which to post process in LR or your favourite post processor.

No comments:

Post a Comment