Thursday, April 17, 2014

Noiseless Post Processing: fact or fiction?



I have posted before about the ground breaking work being done by Alex and others over at Magic Lantern. For some, however, my posts must fall on deaf ears, ie Canon-specific. 

This post is different, it is about an ML-developed tool for all camera users, but especially those with Ligthroom.

It is an adaptation of a piece of software called Zero Noise: http://www.guillermoluijk.com/article/nonoise/index_en.htm . The ML adaptation is called CeroNoice. Basically it creates a 'new' RAW negative from a bracket set, with no noise!

I think it is an exciting tool, but, as many things over at ML, to use it requires some handraulic work: that is until now.

Until this week, I had never written a Windows .bat script, but I sensed this is what I needed for my workflow with CeroNoice and Lightroom. Thus what follows is how I have done it and got CeroNoice running for me. To be clear, ‘all’ I want to do is use CeroNoice to create a noiseless 32-bit (tif) negative, starting with a set of bracketed .cr2 files. That is, I’m not interested in .dngs and not using LR. I want an LR workflow.

So this is my LR-based workflow: I have appended the .bat file I wrote to the end of this post (which I’m sure will have the experts cringing, ie I’m sure it could be more efficient: but it works for me).

First, set up a Folder where you will do your ‘out of LR’ processing, eg a folder called CeroNoice, or anything you like.

In that folder place the following executables, which you will find references to on the ML site http://www.magiclantern.fm/forum/index.php?topic=9581.0: CeroNoice.exe, dcraw.exe, dng_validate.exe and exiftool.exe. Note: I’m not even sure you need all these, but there is no harm placing them in the folder. Also note: read the stuff on the ML site, you must have the right/latest versions, ie each piece of software needs to be compatible with the others.

Open up a .txt file, eg in NotePad, and paste in the .bat text below and save this file as a .bat file, ie with a .bat extension. You can call it what you like, but make sure it is in your processing folder.

The Folder is now set up.

Now go to Lightroom (you don’t have to use LR to get your .cr2 files into the processing folder, but this is how I do it.) Set up an export preset, with the following attributes:

  • Identify the processing folder as the export location 
  • Don’t identify any sub folder 
  • Select file naming as Custom Name – Sequence 
  • Enter “in”, without quotes or spaces, as the custom text (key point) 
  • Select Original as the File setting format, ie the .bat file works with .cr2 files. You will need to change the .bat if you use .dngs. 
  • Save this as an export preset, eg called, say, CeroNoice

You are now ready to process .cr2 brackets.

Go to the brackets you are interested in processing, say, x of them. Select the darkest one (key step!) and holding the Ctl button down left click on the other brackets you wish to select, in a darker to lighter manner.

You will now have x images selected. Now right click on the brackets you have selected in order, and choose export…

Select the CeroNoice preset and press export. If you are doing multiple brackets, you only need select export with previous next time (unless you have used another preset in-between), BUT, only process one bracket set at a time!

Now go to the folder you set up, where you should see x .cr2 images and x .xmp files.

Now double click the .bat file.

The .bat file will do its stuff and create a 32-bit Tiff called out.tif. All input files will be deleted.

You can now play with the 32-bit Tiff, say, in PS-CC or ACR. But, as I said, this post is for the LR users.

Go back to LR and the library module, select import… , select the folder where the .tif is, there should only be one image there, ensure move is selected, select your ‘To’ folder, ie where you wish to move the 32-bit file to, and press Import.

The file will move from the processing folder, so this is ready for another bracket set, and now it will be in LR, ready for 32-bit processing!

The file will be large! Very large!

The file will, at first, be green and dark!

It will have a +/- 10 Ev range!

However, all the LR processing tools work at the 32-bit level, including the WB. So it is easy in ACR or LR to get the look you want.

For example, here is a processed image from three brackets:


Finally, here is the .bat text. As I said it is far from perfect, but is functional (although I do get warnings, it appears to not matter!) 

@echo off



title CeroNoice Processor



set brackets=0



for %%n in (*.cr2) do set /a brackets=brackets+1



echo %brackets%



set /a brackets=%brackets%+1



set counter=1



set cero=ceronoice.exe



:begin



set  cero=%cero% in-%counter%.cr2



set /a counter=%counter%+1



if %counter% EQU %brackets% (

goto continue

) else (

goto begin

)



:continue



%cero%

dng_validate.exe -3 out out.dng



rem ensure all the input and working files are deleted

del *.xmp

del *.cr2

del *.dng



exit

 


Bottom line: please don't take my word for the noiseless claim. I believe if you decide to put a little effort in setting the above up, you will also be amazed at the quality of your (new) digital negative!

2 comments:

  1. I really like the blog.I have shared your site with many friends and family. It is always a pleasure to read..
    Shannons Point Of View

    ReplyDelete
    Replies
    1. Many thanks for the feedback. My aim is to try and help those looking for a slightly more technical insight, especially if you shoot with Canon.

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