From all 6 files in the above archive only the 2520x1304 Normal one seems to be free of focus pixels.
Maybe the application you are using can already handle this file. Here's how I check for focus pixels and create a map file. Note that no programming skills are necessary just a basic understanding on how to use the terminal. You'll also need mlv_dump installed on your system along with some common command line tools -- bash, sed, file, dcraw and Imagemagick.
First use mlv_dump to make some dng files. Use the --no-fixfp option to make sure mlv_dump doesn't attempt to fix the focus pixels. (Click on the screenshots if you want to see them at full resolution.)
Tip: You can drag the mlv file into the terminal window so you don't need to enter the path and file name. I'm working in the same directory as the mlv files to keep the illustrations simple.
If you open one of these dng files in Resolve or ACR you might have a hard time seeing the focus pixels because these applications tend to smooth them out. In order to get them to pop we'll use dcraw to convert one of these dng files to tiff.
Open the tiff in Photoshop or Gimp. It should look fine when looking at the whole frame.
However, zoom in and punch up the saturation and vibrance.
It is rather easy to create a new layer and hit these focus pixels with the pencil tool but first we need to make some adjustments in order to line up the map file.
The way the apps work with the focus pixel map files is that they first look at the full image buffer size and determine where the image is located on that buffer using the crop and pan information. We can do the same thing in Photoshop.
We are going to adjust the canvas size (not the image size!) so we need to turn that background into a layer.
Next, make the canvas size the same size as the full raw buffer. Use this command to easily scroll through the mlv_dump -v output:
mlv_dump -v 100D_Normal_2520x1304.MLV | lessThe full raw buffer size can be found in the RAWI block:
Adjust the canvas size so it is the same as the full raw buffer:
Next, the image needs to be moved around on the canvas so that it matches what is in the mlv file. Once again, using mlv_dump -v:
We're interested in the Crop. In many cases the Pan will have the same values but not always. For example, on the 700D full resolution 1x1 file it came out like this:
Crop: 72x30
Pan: 72x31
Ok--back to the one we're working on, move the image so that it is lined up according to the Crop data. Zoom all the way in on the upper left corner of the canvas:
Now we can make a new layer and start hitting those focus pixels with the pencil tool. Make sure the tool is adjusted to 1 pixel and black.
You'll quickly find out that there are lots of focus pixels and this is very tedious. You'll also discover that there is a pattern but if you try to copy this pattern to other areas of the image there might not be any focus pixels there or there may be focus pixels that aren't covered.
I have never seen an image that shows all of the possible focus pixels, however, by working over an area, looking for a pattern and extending it over the entire image area you will eventually cover all the focus pixels. The way I do this is by copying the layer then moving the copy to extend the pattern, merge the layers, make another copy -- rinse repeat until the entire image is covered.
You'll notice that with the settings that easily show focus pixels, like 14-bit lossless, the focus pixels are confined to a defined area. So why map out the entire sensor? We found out that settings that don't easily show focus pixels, like 8-bit lossless, focus pixels will appear in areas that are not confined to a defined area. They usually show up in high contrast boundaries. Since this is video and the image is constantly changing the focus pixels pop on and off and give a "sparkling" effect. Thus it is important to map out the entire image area.
Now make a new white opaque layer and place it under the layer with the focus pixels that you just made, zoom back a bit and you should see a definite pattern.
You'll note that the focus pixel layer extends to areas where the image ends. This isn't a problem though I prefer to remove the extra focus pixels that are in the out of bounds area of the full raw buffer.
Now save the focus pixels as a portable bit map file and name it with the camera model number and the full raw buffer size:
There are a few scripts and applications that can turn this pbm file into a fpm that can be used in MLVFS. I'm going to use my pbm2fpm.sh
[EDIT] I renamed it to img2fpm.sh because if you have ImageMagick installed it can use any image file format -- not because it is the best or fastest but I wrote it and know how it works. Photoshop saves what are known as P4 portable bit map files which are binary files. This is a bit of a problem with bash so the script uses ImageMagick to convert it into a P1 ascii file. The script is rather slow though I have optimized it so it isn't as bad as it used to be. I prefer running it with the -v option to see the progress.
[EDIT] The -v option is now the default. Use the -q (quiet mode) option if you are piping it through your own scripts.Ok--here we go:
Now take that 80000346_2592x1332.fpm we just created, drop it in with the other map files in MLVFS and let's check to see if it is working.
Starting with a pixel peeping view of the normal file without fixing the focus pixels:
Here is how it looks like in MLVFS using the map we just created:
Looks good. How about the dual iso example?
Oh no! Did we somehow miss those focus pixels that are showing up? I put this frame into the Photoshop project and turned on the focus pixel map layer we just created:
Looks like those stray focus pixels that are showing up are mapped so what is going on? In order to fill in the focus pixels we need to average in the surrounding pixels. Because of the way dual iso works, the line above or below will probably be so different that averaging the area immediately above or below a focus pixel won't work so we can only average pixels on the horizontal axis. This means that when we hit a contrasty vertical line, there just isn't enough information to fill in the focus pixel. At least that's how I understand this works with MLVFS, other apps may be different.
The best we can do with MLVFS is to turn on some chroma smoothing:
Yes, a tiny bit is still there and some users say that they can see some reduced resolution with chroma smoothing on (I can't see it) but that's the limitation we've got to work with until someone figures out something better.
