[secateurs]

Hi everyone,

As a student on a budget, I was wondering what I can use for PP.

In the past, i've only used very basic functions in Irfanvew. I would like to up my PP skills and ability, and I think software is a first step.

How does The Gimp do for PP? Does it read Pentax RAW files? Are there any good starter tutorials out for manipulating photos in The Gimp?

Any other information or suggestions regarding free PP software would be great! Thanks.

[boriscleto]

Paint.NET - Free Software for Digital Photo Editing

Paint.net will import DNG files.

Tutorials

Plugins

[dosdan]

I've written 2 GIMP photo tutorials. You'll find them in
Post-Processing Articles - PentaxForums.com

You can install UFRAW to open raw files - it ties in with The GIMP. You can either open the raw file in the GIMP (UFRAW is invoked to import it). Or you can open the file in UFRAW and then send it to GIMP with a button that invokes The GIMP.


Dan.

[JoeGray]

Hi Secateurs,

I've used both Photoshop CS3 and The GIMP and often find myself choosing The GIMP because I find it faster and more intuitive to use!

As Dosdan pointed out above GIMP can be used in conjunction with UFRAW to decode pentax RAW files just fine. (In fact I'm surprised UFRaw isn't bundled with The GIMP it's so useful)

Some things I find superior with GIMP:
- I find the curves function far superior in GIMP (I use this feature a lot). Small adjustments are easier and all previous settings are automatically stored (in addition to being able to import/export favourite settings).
- Tool options are far more accessible (to me) in GIMP (eg. it's far easier to set a 1:1 crop ratio for an automatic square crop)
- The entire GIMP program (including all personal profile settings) can be ran from a USB stick for powerful post work where-ever you want.

Drawbacks:
- Top shelf plugins (such as de-noising software) are made to work with PS. They can be persuaded to work with GIMP (great for must-have plugins!) but the experience is often far from ideal.
- Adjustment layers are non-destructive and can be stacked and modified after the initial settings are selected (for me this is a double edged sword: when I'm masking multiple layers and want to apply adjustments to some layers only, the grouping of layers can get tricky)

If you'd like to give GIMP a go and want a head start I'm happy to dig up some of my profile files for you. Since I use GIMP primarily for photo work, these should arrange the most useful tools, give you presets for the curves (and possibly other) functions and I'll include a couple of the best GIMP plugins for denoising, sharpening, guides, etc.

I'll also write a brief tutorial of a basic (and probably terribly flawed) post-processing workflow if anyone's interested.

Feel free to ask any questions and I'll try to promptly get back to you.

Cheers,
Joe

[MetteHHH]

I have used the combination of file sorting in FastStone, RAW editing in UFRaw and basic adjustment in GIMP for years. I think it is a great combination and makes for a very good workflow.

Right now, however, I am struggling to learn to use the Pentax software for RAW editing, basically because I realised how far superior noise reduction is relative to that in UFRaw. I know new software requires some getting used to, but so far I hate the Pentax interface. The FastStone + GIMP combination is SO much more user friendly - in my view. Yes, curves work wonderfully in GIMP - one of my favourite tools also.

If you can get a better noise reduction program (Topaz?) to work with GIMP, like JoeGray sais, then it would be the winning combination in my view.

Then again, from this forum I have learned that the 8-bit colour space in GIMP is really destructive to colour depth. Something I have never noticed myself, but it makes me a bit anxious. Later versions of GIMP plan to use 16-bit colour editing, but they are not there yet.

[mmickey]

You could have a look at Photivo. In first place it is a 16bit RAW converter (but takes also bitmaps) like UFRaw and exports to gimp afterwards, but it has many more features...

To learn gimp, Meet the GIMP is a great page.

greets mickey

[jolepp]

I have been using the FastStone, ufraw & Gimp combination on Windows as I would like to have the option to use the two latter on Linux too. I'm quite sure the Adobe stuff is more convenient and the price for Photoshop Elements is not bad either, so I have been tempted to get that. However, after much tinkering I've found that the following works for me (most of the time :-):

1) Import pictures (I use .DNG) in FastStone,

2) for the better ones launch Gimp from the right mouse button menu,

2.1) This brings up the image in ufraw where I use the default settings mostly, except:

2.1.1) "Color Matrix", gamma=0.34 and linearity=0.063 under "Color Management", these seem to produce similar results to k-x's Natural preset, YMMV.

2.1.2) under "White Balance",

- adjust exposure keeping an eye on the preview and the histogram (try to bring it to the middle, avoid overexposure)

- adjust WB if camera setting doesn't look good (lower K values to correct yellowish tint typical for tungsten light, higher K for bluish tint typical for shadow light outside, or pick a reasonably white/grey spot and use the eyedropper button to set based on that and adjust to suit)

- "Apply color smoothing" (have the button with the paintbrush icon 'down')

- Denoise if needed (high ISO), a rule of thumb could be: 20-40 "slight", 40-80 "moderate", 80-160 "heavy"

2.1.3) "Correct luminosity, saturation"

- Use auto black point and maybe adjust the curve for more contrast (see attachment)

3) Launch Gimp (with the OK button)

- crop and resize as needed

- sharpen with unsharp mask (try e.g. radius=2, amount=0.5, threshold=5.0 to get started, adjust amount first)

- save as JPEG (70% = "*" quality, 95% ="***" quality)

At all points I do saves as JPEG to the same directory where the DNG is for convenience and use FastStone's full screen view to see the results.

Note: by default ufraw uses the settings from last time, so look out for that.

---

Last edited by jolepp; 03-16-2011 at 08:57 AM.

[Lowell Goudge]

I know it is not what you asked, but what about Corel's PSO X3.

It supports pentax RAW (PEF files) although they can be a little slow updating for new releases of cameras, but more importantly, it can do everythign that photoshop can do, and I have even noticed now that popular photography is starting to make reference to it in PP discussions, by giving the photoshop equivelent menu functions.

I have used it since I went digital starting with JASC software's version 8. Corel bought Jasc after version 9

[boriscleto]

I know it is not what you asked, but what about Corel's PSO X3.

It supports pentax RAW (PEF files) although they can be a little slow updating for new releases of cameras, but more importantly, it can do everythign that photoshop can do, and I have even noticed now that popular photography is starting to make reference to it in PP discussions, by giving the photoshop equivelent menu functions.

I have used it since I went digital starting with JASC software's version 8. Corel bought Jasc after version 9

The OP is looking for free, not commercial SW. PaintShop and Photoshop Elements cost money. These don't.

Best Free Paint Program

Freebyte's Guide to...
Free Graphics Software

[secateurs]

Thank you everyone for your ideas. I had no idea that The Gimp was limited to 8 bit colour. That could be a deal-breaker for me.

I will have a look into some of the other suggestions.

[dosdan]

Thank you everyone for your ideas. I had no idea that The Gimp was limited to 8 bit colour. That could be a deal-breaker for me.

I will have a look into some of the other suggestions.

A 8-bit image has 24-bit colour (3 bytes per pixel i.e. 3 x 8 bits). This is the the same as used in JPEGs, BMPs & 8-bit TIFF. It allows 2^24 tonal variations in colour which is way above what the human eye can perceive. RAW converters use 16-32 bits internally so if you do your major tone curve adjustment, colour adjustments & exposure boosting in the raw converter before importing to GIMP you should be fine.

Sharpening, cropping, resizing, geometric distortion & NR operations do not need 16-bit (48-bit colour) images.

The symptom of lack of bits is posterisation (e.g. banding in the sky) caused by large level boosting of an 8-bit (24-bit colour) image.

Dan

[Lowell Goudge]

The OP is looking for free, not commercial SW. PaintShop and Photoshop Elements cost money. These don't.

Best Free Paint Program

Freebyte's Guide to...
Free Graphics Software

Paint shop pro is on sale for a very good price on the corel site

[boriscleto]

Paint shop pro is on sale for a very good price on the corel site

Not in Australia.

[secateurs]

A 8-bit image has 24-bit colour (3 bytes per pixel i.e. 3 x 8 bits). This is the the same as used in JPEGs, BMPs & 8-bit TIFF. It allows 2^24 tonal variations in colour which is way above what the human eye can perceive. RAW converters use 16-32 bits internally so if you do your major tone curve adjustment, colour adjustments & exposure boosting in the raw converter before importing to GIMP you should be fine.

Ah, thanks. I understand a bit better now.