always i get color image degradation whenever i apply new gradient layer?
for example: i have green meadow with clear blue sky and i add new layer and apply black gradation filter on the sky
and then change opacity from (0-100) until i get the best look
and also change to overlay or soft light
i always get degradation of the color on the sky
i have tried everything and i work with TIFFs only and layers as well still and nothing?
i have checked the my CS4 system preferecnes/performance and i just can not figure it out what could casue color degradation of images?
please any help or advice how i can avoid this in the future
i add new layer and apply black gradation filter on the sky
It's not clear what you mean by this. What's a "black gradation filter"? If it's just adding black, no wonder it looks degraded.
Anyway, the way to do this is to add a Curves adjustment layer. Then fill the layer mask with the appropriate gradient (using the gradient tool).
This should, if anything, increase saturation in the sky. You can predict this (side-)effect by looking at the actual curve. Wherever the curve is steeper than it was, saturation increases. Wherever it's shallower than it was, saturation decreases.
It can also be done with Levels. Adjusting the midpoint slider is equivalent to a curve with one point.
All those saturation effects can be annulled by setting the adjustment layer to Luminosity blend mode. And combinations thereof.
i don't know how much you can see here
i posted the orig file
but they have skaled the image to fit it here
take a look at the sky you will see like horisontal lines (from the graduation filter in CS)???
OK. That's banding - happens with gradients when you work in 8 bits per channel.
In 16 bits banding is usually not a problem.
Sometimes adding a little noise and then a little blur can fix it.