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View Full Version : Curves. Graphic examples



Geoff Chandler
12-05-2007, 04:01 AM
After chatting in other threads, I decided to give some basic curves examples for those who find them a mystery.
I have kept it as simple as possible - so I am NOT including the associated histograms, I am not covering saturation, and I am not doing the simple brightness and contrast adjustment - all of which can also be an important contribution.
To understand and see - visually, how curves work, first, is my aim.
Those who saw my thread on Dealing with difficult yellows will recognise the example photo.
Sorry - but the easiest way for me is to perform about 12 posts ...

1st example is the untouched image

Geoff Chandler
12-05-2007, 04:03 AM
Increase shadow/lowlight detail/level

Geoff Chandler
12-05-2007, 04:04 AM
Decrease shadow/lowlight detail/level

Geoff Chandler
12-05-2007, 04:06 AM
Increased highlights

Geoff Chandler
12-05-2007, 04:07 AM
Decreased highlights

Geoff Chandler
12-05-2007, 04:09 AM
Straight line brighter

Geoff Chandler
12-05-2007, 04:12 AM
Curved line brighter

Geoff Chandler
12-05-2007, 04:13 AM
Straght line darker

Geoff Chandler
12-05-2007, 04:14 AM
Curved line darker

Geoff Chandler
12-05-2007, 04:15 AM
Straight line shadows lighten

Geoff Chandler
12-05-2007, 04:16 AM
Straight line shadows darker

Geoff Chandler
12-05-2007, 04:19 AM
Finally - using the whole curve.
Anchoring the darkest point and lowering the shadow zone, fixing the mids and raising the highlight and also the overall top brightnes = 5 points of control.
NB- this example was purely all colours - you can also do this in Red, Blue & Green independantly.
Again - I didn't include the histograms as I didn't want to confuse newcomers to the art.

Hope this was helpfull to some people.
Best wishes
Geoff ;)

downtrodden
12-05-2007, 06:25 AM
thank you! it's easier to scrool back and forth on some examples and see what the apporopriate change did exactly to the image instead of trying to do it in Gimp and wonder exactly. Thank you for taking the time to show exactly what each point on the curve is used for!

toriaj
12-05-2007, 08:10 PM
How do you use those curves? Do you have each one on a separate layer? Or do you actually only use the last one?

Phill D
12-05-2007, 10:19 PM
Geoff looks like you were up late doing that little sequence. It was well worth it though certainly for me as that has really explained how to start with curves. I had played before with borrowed editing software but just found it too confusing so had given up. I think you might have just sorted out a Christmas present my wife can get me ;). Thanks again for taking the time to post these.

Geoff Chandler
12-06-2007, 02:26 AM
How do you use those curves? Do you have each one on a separate layer? Or do you actually only use the last one?

Simply open the image in your graphics package.
Open curves (however that is executed in your particular package)
Adjust the curves until your image looks OK - notice on the example
(Serif Photo Plus) I had the preview ticked.
Save as - and I always rename so I can go back to the orig if I change my mind.
Bingo - job done

Geoff Chandler
12-06-2007, 02:28 AM
Geoff looks like you were up late doing that little sequence. It was well worth it though certainly for me as that has really explained how to start with curves. I had played before with borrowed editing software but just found it too confusing so had given up. I think you might have just sorted out a Christmas present my wife can get me ;). Thanks again for taking the time to post these.

Brilliant!
Which software will you get??
I must treat myself to something new sometime
- My main two packages are both limited.
Glad to have been of some help
Geoff;)

Phill D
12-15-2007, 12:43 PM
Geoff I have just tried to tweak your original flower shot Geoff to see what I could get by way of a trial o the curves feature in photoshop Elements 6. As you had shown so many stages I could compare what I got with your examples. This is what I ended up with what do you think?

Geoff Chandler
12-15-2007, 02:40 PM
Obviously without the benefit of seeing the flowers in the flesh you are working blind
With that in mind - I reckon that is top notch!!
I really should treat myself to a similar program - i dodge between Serif Photo Plus and my KM Dimage Viewer - which has the benefit of NOT destroying the exif data. Serif Photo Plus is a touch slower but more precise. Dimage Viewer does grreat quick fixes - but there is no noise tool and the sharpening is crude.
So - more examples of Photo shop elements please - I think that could be top of my lost!!

Phill D
12-15-2007, 11:03 PM
Thanks Geoff I've still got 27 days of the demo trial to play but I don't expect to get much free time before Christmas. I've pretty much decided I'll buy it though so will play over the holiday. The interface is very easy to use & nice on the eye. I'm sure someone has done back to back comparisons with other products somewhere but it seems to do what I need for now fairly easilly & there are lots of tutorials & help in the magazines to explore. Those changes on your flowers took less than 5 minutes & I don't know what I'm doing yet! So I'm afraid life's too short to go downloading any more of the competitors programmes & do a proper comparison. I did look at Serif 6 which seemed OK but it just didn't have the versatility, maybe the newer versions do but as I said I'm going to stick with the market leader for now.

Geoff Chandler
12-16-2007, 12:51 AM
Photoshop elements would be better than Serif 6 - and also almost certainly better than Serif 8
Serif 8 doesn't seem to have any easy form of redeye reduction, neither does my Dimage Viewer - for that I switch to 'Arcsoft Photo Impressions 4'
Which also destroys the Exif data :eek:
Only Serif Photoshop 10 is up to the standards we are talking about - they did offer me it for 26=uk a while back - so I may well consider that instead when the time comes

hokeyguy
12-16-2007, 11:44 AM
Here's a nice little link (http://www.adobe.com/go/lr_dc_tutorial_adjust) for a video showing Adobe Lightroom's curve adjustments. Lightroom has an interesting limiter to help prevent you from going too far.