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JohnGG
28th May 2008, 10:10 PM
I have only ever used the simplest of post processing tools; Olympus Viewer with the E-1 and, more recently, Master 2 with the E-3. I have mainly confined myself to "Brightness & Contrast" and "Sharpness & Blur". I decided to get adventurous the other day so I loaded the trial version of Studio 2 that came with the E-3 and opened up a raw file to process.

It quickly became apparent that I was deluding myself if I thought I had any idea how to proceed :mad: I hadn't a clue which of the myriad tools I should be using or in which order they should be deployed. Neither was I sure what I was trying to achieve with the image or even what was possible :o

In short, I need to find a good book on digital darkroom techniques or a good tutorial on the web. I have had a Google and have found many links but I have no way of telling whether they are nuggets of information or dross :(

I wonder if anyone could suggest a good book or tutorial that will help me make a little progress into this mysterious realm *read

Cheers,

JohnGG

Scapula Memory
29th May 2008, 06:54 AM
No doubt there are many good books you could get for learning about PP but a good start might be the free raw converter program rawtherapee http://www.rawtherapee.com/

It may be free but it is fully functional and has all the features you could possibly need at the moment, plus a few more.

It has a very good easy to read manual that does not blow the average user away ( only about 30 pages ) but explains stuff more or less in laymans terms. It also suggests a workflow which is apt not just for rawtherapee but most other PP applications. It goes along the lines of process in this order.

white balance
resize
rotate
distortion correction
Chromatic abberation correction
vignetting correction

The above settings, it suggests influence an image the most, then the basics

exposure and or luminance curve
colour changes/saturation/shift
shadows/highlight changes including highlight recovery if required
noise reduction ( luminance and colour )
sharpening.

Then conversion to chosen format.

I found it very helpful. For most images under many conditions only slight changes are needed.

Naturally many others might suggest different approaches but this one is a pretty good start. I feel it is something worth learning because shots you thought were not keepers can all of a sudden be transformed into very pleasing images. Raw files at least give you the headroom for change in the knowledge that the originals are always there unscathed to go back to.

One other neat aspect of Rawtherapee is that it can be run from a memory stick. No install required, something I have found extremely useful.

good luck!

PeterD
29th May 2008, 07:27 AM
Hi John

That sounds like a damn good stear to me. One of the many tasks I have not yet mastered is PP. I think I mentioned it some months back. Although I have bought Lightroom and Photoplus, I too need that bridge between the detail and the practical side. I shall have a look at what you have offered.

Many thanks

Nick Temple-Fry
29th May 2008, 08:00 AM
white balance
resize
rotate
distortion correction
Chromatic abberation correction
vignetting correction



Re-size 2'nd - must admit it's about last on my list, even cropping is likely to be further down the priorities. Just nit picking but I like to get the best 'full' image from the biggest possible file.

(good list though - but do we have abberration or vignetting with Olympus Zuiko lenses - perish the thought;))

Nick

Scapula Memory
29th May 2008, 08:17 AM
Hello Pete,

Hope it is of some use! Good start with the blog, some nice images there and a great idea to add some notes and story to the pics. Also the settings are easy on the eye unlike some other blogs I have seen that are full of flashes and bangs:)

Scapula Memory
29th May 2008, 08:32 AM
Re-size 2'nd - must admit it's about last on my list, even cropping is likely to be further down the priorities. Just nit picking but I like to get the best 'full' image from the biggest possible file.

(good list though - but do we have abberration or vignetting with Olympus Zuiko lenses - perish the thought;))

Nick

Not sure, would you lose the same detail if you crop at the start of the workflow as you would the finish?

One other thing about Rt is that Olympus users should set the demosiacing alogorithm to the VNG-4 standard as this reduces mazing artifacts caused by the other alogorithm.

Barr1e
29th May 2008, 08:35 AM
I seemed to have developed a simple routine with my pp (Elements 5) and found gradually over time to expand what the program can do to help my images.
One of my favourites after correcting is to try and make the image pop.
I make a layer (Ctrl J) then using the drop-down menu on the right (Normal)
choose 'Overlay'.
Next to the drop-down menu box is shown a slider symbol '100%'.
Using the slider I drop this setting down to about 30% or so until I think the image pops or not then flatten use usm and crop.

Hope that might be of some help.

Regards. Barr1e

Nick Temple-Fry
29th May 2008, 08:48 AM
Not sure, would you lose the same detail if you crop at the start of the workflow as you would the finish?

One other thing about Rt is that Olympus users should set the demosiacing alogorithm to the VNG-4 standard as this reduces mazing artifacts caused by the other alogorithm.

Well crop and resize are different - resize alters the number of pixels as it sets the image size in pixels - therefore if you resize you lose information and the file becomes smaller.

Crop is when you harvest part of your image - so no you do not lose detail, merely through away all those expensive pixels outside of your crop you paid Mr Olympus an arm and a leg for.

Thanks for reminding me about the Rawtherapee documentation - I'd downloaded and forgotten about it.

Nick

JohnGG
29th May 2008, 09:41 PM
Thank you all for the useful information. I have had a look at the Rawtherapee site and the manual and workflow diagram are more than helpful; for instance, the explanation of colour spaces makes a lot more sense to me than anything I've seen before ;)

I will install the package and see if I can make some progress. A couple of further questions.

Am I right in thinking that Rawtherapee is purely for the conversion of RAW files and that further more complex manipulation of, say, selected areas of an image would be better addressed with Photoshop, the Gimp or something similar?

To do further processing in another package, what is the best format in which to save the image files and can separate channel information be preserved?

Cheers,

JohnGG

Scapula Memory
29th May 2008, 10:45 PM
Am I right in thinking that Rawtherapee is purely for the conversion of RAW files and that further more complex manipulation of, say, selected areas of an image would be better addressed with Photoshop, the Gimp or something similar?

To do further processing in another package, what is the best format in which to save the image files and can separate channel information be preserved?

Cheers,

JohnGG

Yes, whatever raw converter you use you are preparing a finished article to be converted to a format of your choice for more trickery in Photoshop or equivalent.

Your choice of conversion format will depend on what you want to do, TIFF is a good choice with your final image as a jpeg.

JohnGG
30th May 2008, 11:23 PM
I've now installed RawTherapee and it already looks rather impressive. Some of the pictures from my visit last weekend to the Strumpshaw Steam Fair were taken in a red marquee so they had a very strong colour cast. I'd struggled to remove this effectively using Olympus Master but it was ridiculously easy by comparison and with vastly better results using RT.

Thanks again everyone for all of the useful pointers :)

Cheers,

JohnGG

HughofBardfield
2nd June 2008, 11:04 AM
I think if you have a good RAW converter, the amount of PP work you need in A N Other application diminishes greatly.

I like Lightroom, probably because I've got used to it, and the V2 Beta suggests the next version will mean even less recourse to Photoshop as it adds vignetting and dodging/burning tools.

However, I find Raw Therapee is particularly good at highlight recovery (much better than Adobe Camera Raw) as it can use the DCRAW converter. However, I also use Lightzone on some "difficult" images, and find it's particularly good for B&W.