Ok, I'm not an expert at this but I've been doing some research and played around last night with a couple of images taken in Gran Canaria last year. Was interested in learning how to rebalancing the colours to counteract the loss of certains colurs at depth. These images took me less than an hour in total and I know they ain't the greatest but they show what can be achieved with relatively little experience or time.
The trick is to know what is happening when you alter something like Hue / Saturation and Intensity. A trick for you, try to alter a colour in RGB using gamma and contrast only. Gamma alters the linerarity of the gray scale of the chosen channel without removing any information of the channel. Hue will alter the actual colour and can create uncomfortable effects. Also, the reason most compression techniques make altering colour difficult is they actually remove colour information by "bining" colour pixels together. The theory is that the eye is less effective at seperating subtle colour changes than changes in colour satuation or greyscale intensity.
Unsharp masking works by first bluring the channel using a low pass filter, then subtracting the blured data from the original file then applying a multiplication to increase the intensity values of the de-blured data. It can be very harsh. Try to increase the radius and use the threshold to protect the values in the image data.
If you want more information please ask, this is what I do for a living, it has fascinated me for the better part of 15 years.
Ohh great,
even thou i have bugger all time left at night, now I am going to have to start learning photoshop, Which has sat untouched on my comp since new...
Gee thanxs Jay,
I suppose I can sleep between 2 and 4am lol
awesome improvement thou, I am most impressed
well time to start learning
Steve
The trick is to know what is happening when you alter something like Hue / Saturation and Intensity. A trick for you, try to alter a colour in RGB using gamma and contrast only. Gamma alters the linerarity of the gray scale of the chosen channel without removing any information of the channel. Hue will alter the actual colour and can create uncomfortable effects. Also, the reason most compression techniques make altering colour difficult is they actually remove colour information by "bining" colour pixels together. The theory is that the eye is less effective at seperating subtle colour changes than changes in colour satuation or greyscale intensity.
Unsharp masking works by first bluring the channel using a low pass filter, then subtracting the blured data from the original file then applying a multiplication to increase the intensity values of the de-blured data. It can be very harsh. Try to increase the radius and use the threshold to protect the values in the image data.
If you want more information please ask, this is what I do for a living, it has fascinated me for the better part of 15 years.
Superb Andy - don't suppose you fancy doing a PS Tutorial using examples to show us how its done? I'm just starting to scratch the surface and I have seen some stunning images elsewhere.
Just got back from lanzarote and will be posting some more piccies after I`ve run em thru photoshop.
Great hol, good diving and trip report will follow.
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