"Swirls" in the background
Sep 17, 2014 12:00:42 #
Bozsik wrote:
Relevant and accurate answer. :thumbup: :thumbup:
it was relevant and accurate but how does it explain this pair of images?
There is no shading in the background.
Sep 17, 2014 12:39:31 #
Thanks to all who assisted me in solving this problem. I had set the Jpeg resolution very low in PSE11.
Sep 17, 2014 12:41:30 #
Great to see the comparison + I love that shot :thumbup: :thumbup:
Sep 17, 2014 23:16:06 #
oldtigger wrote:
it was relevant and accurate but how does it explain this pair of images?
There is no shading in the background.
There is no shading in the background.
Since it is all but impossible to light a background exactly evenly, there were subtle variations in the exposure. They may not have been discernible to the naked eye.
When an image goes through jpeg compression the algorithm will look at adjacent pixels and make a determination whether they are close enough to display as the same value or are they different enough to show at another level. When converting to a low resolution jpeg, the algorithm will allow a rather wide range of values to be displayed as the same value. However, when the threshold is reached for the algorithm to display a pixel at a different level, the change can be rather abrupt resulting in the sharp edges seen in your backgrounds. An overall, random pattern is produced as the levels go up and down. In the end, the higher the resolution, the less abrupt those transitions will be.
Sep 21, 2014 11:13:24 #
Looks to me that your your colors are out of gamut for your colorspace. Your rendering engine is replacing the missing colors with colors that are in gamut for your colorspace causing the banding.
Under exposure will do this too.
My suggestions are to shoot in sRGB and in RAW start from there with a familiar lighting scenario. This image you supplied is underexposed. Us a higher ISO and wider aperture. Adjust you white balance.
Under exposure will do this too.
My suggestions are to shoot in sRGB and in RAW start from there with a familiar lighting scenario. This image you supplied is underexposed. Us a higher ISO and wider aperture. Adjust you white balance.
Sep 21, 2014 11:15:26 #
Looks to me that your your colors are out of gamut for your colorspace. Your rendering engine is replacing the missing colors with colors that are in gamut for your colorspace causing the banding.
Under exposure will do this too.
My suggestions are to shoot in sRGB and in RAW start from there with a familiar lighting scenario. Use a higher ISO and wider aperture. Adjust you white balance.
Under exposure will do this too.
My suggestions are to shoot in sRGB and in RAW start from there with a familiar lighting scenario. Use a higher ISO and wider aperture. Adjust you white balance.
Sep 21, 2014 15:12:17 #
GTinSoCal wrote:
That's called posterization.
It happens when a nice gradual fade from one color to another is redefined in fewer colors/shades.
It can make for an amazingly beautiful effect, but really sucks when you aren't looking for it.
GT
It happens when a nice gradual fade from one color to another is redefined in fewer colors/shades.
It can make for an amazingly beautiful effect, but really sucks when you aren't looking for it.
GT
Excellent explanation. Tks
Oct 10, 2014 08:25:59 #
Can't say for certain what caused those, but post production is the likely culprit. But, I have to say the bands or swirls if you like do have their own beauty!
Oct 10, 2014 11:18:14 #
Meryl08 wrote:
Can't say for certain what caused those, but post production is the likely culprit. But, I have to say the bands or swirls if you like do have their own beauty!
Thanks, birdpix nailed the problem. I had them at too low resolution.
If you want to reply, then register here. Registration is free and your account is created instantly, so you can post right away.