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DMC-FZ50 RAW files from our own camera


We've now bought a camera, and we're in the process of getting the hang of it. Text below is the stuff we've managed to learn before we had the camera.


My love needs a 10 mega-pixel camera for some project, so we've found out that Panasonic DMC-FZ50 was pretty cheap for a 10 meg box, and got a nice review at DCRP that also happened to be the only page on the net [at least at the time this was written] that gave an example 20MB raw file produced by such a camera.

Here is a reduced version of the 10 mega-pixel monstrocity:

It so happens that this photo was deliberately shot at ISO 800 (which is something that guarantees noise) in order to explain how you can solve noise problems [if you happen to have an operating system that costs money and are willing to buy software that costs some more money].

[ Of course, you can now download example DMC-FZ50 raw files here ]

This, then, made some people doubt whether we (being GPL-heads) could deal with such RAW files at all.

Here are some experiments we did with the command line dcraw and the gui-enabled ufraw, in order to show the results they deliver to adobe-oriented friends and get some estimate whether our solutions are good enough for print, and if not - what we should improve. Anyway, both dcraw and ufraw

For the rest of this page, we'll work on a 800x600 rectangle of the image in order to enable viewing at 100% zoom without choking the browser. The pictures are also reduced by 50%, so click on them in order to enlarge (since the fine details are what this is all about).

Dcraw - command line interface

Although a command line tool does not give you the real time feedback of "when I make this number higher, the flower becomes too orange", but we've started with it and we've learned some interesting things.

Most important lesson we've learned: Always use Four Color VNG interpolation for Panasonic DMC-FZ50 RAW files (probably true for other models).

Here's how it should look when you simply do

dcraw -v -T -f -w myphoto.raw (switches are: verbose, Tiff, four color VNG, camera white balance)

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Here's how [ugly] it looks with the default AHD interpolation (i.e. without the -f):

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Noise reduction with dcraw (the -B option) looks like:

dcraw -v -T -f -w -B 2 4 myphoto.raw

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Ufraw - graphic user interface:

Since graphic designers tend to sneer at the command line interface, ufraw gives a look-and-feel user interface for fine-tuning dcraw's parameters, as well as some non-dcraw features it computes by itself in 3x16-bit "raw color-space".

One minor snag, though: Ufraw does not support dcraw's noise reduction. This means that [as far as we know] if you have any noise reduction to do, you'll have to do it in the 3x8-bit color-space of the tiff result. On the other hand, we're not planning to shoot at ISO 800 :)

Here's an example ufraw output:

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Note again that all this is done on a photo taken at ISO 800, which is something I thought you only did in bat cave research and such ;)

For less noisy shots and the way we've developed them with ufraw, see DMC-FZ50 RAW files

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changed February 22, 2008