Luminous Landscape Forum

Raw & Post Processing, Printing => Adobe Lightroom Q&A => Topic started by: dreed on May 19, 2012, 05:00:23 am

Title: LR4: Fringing/border of dark vs lighter background = blown highlights?
Post by: dreed on May 19, 2012, 05:00:23 am

The attached image is a cutting from my screen with 100% view in LR4 Develop.

I don't understand why there is this red "fringe" or "border" where everything is highlighted as a "blown highlight".

Is this just a bug in Lightroom or is there some magic required?

Title: Re: LR4: Fringing/border of dark vs lighter background = blown highlights?
Post by: Bart_van_der_Wolf on May 19, 2012, 05:42:11 am

Quote from: dreed on May 19, 2012, 05:00:23 am

The attached image is a cutting from my screen with 100% view in LR4 Develop.

I don't understand why there is this red "fringe" or "border" where everything is highlighted as a "blown highlight".

Specular reflection from backlight? Sharpening halo?

You need to zoom in further and tell us what the RGB percentages are at such 'clipped' positions.

Cheers,
Bart

Title: Re: LR4: Fringing/border of dark vs lighter background = blown highlights?
Post by: Rendezvous on May 19, 2012, 06:47:32 pm

Sharpening increase local contrast - maybe this has caused blown highlights in close proximity to the edges?

Title: Re: LR4: Fringing/border of dark vs lighter background = blown highlights?
Post by: dreed on May 20, 2012, 10:14:45 am

Quote from: BartvanderWolf on May 19, 2012, 05:42:11 am

Specular reflection from backlight? Sharpening halo?

Possibly sharpening halo - reducing the radius to 0.5 reduced the effect but...

Quote

You need to zoom in further and tell us what the RGB percentages are at such 'clipped' positions.

Some of the red still remains and the values are nothing like what I would expect for clipping: 43.7/61.0/78.6 (for example)

Do the RGB %'s represent post-rendering or pre-rendering?