More screengamma

Scott Rossi scott at
Mon May 5 18:39:41 EDT 2014

Honestly Jacque, I've never seen JPEGs affected by screenGamma settings.
The only reason I would imagine this happening is if something was done to
an image after it was imported (resized, edited, etc) that would change
the (I believe) paintConversion to PNG.

I posted a simple test stack here:
go url ""

On my Mac system, the PNG image at the top appears darker than the JPEG
below.  When the slider is adjusted, only the top image is affected (LC
6.6.1, OSX 10.8.5)

Are you seeing something different?


Scott Rossi
Creative Director
Tactile Media, UX/UI Design

On 5/5/14 3:21 PM, "J. Landman Gay" <jacque at> wrote:

>On 5/5/14, 4:03 PM, Roger Guay wrote:
>> The dictionary says "Use the screenGamma property to control the
>> color display of PNG images.² Could that be your problem?
>Yeah, maybe. Only it used to change everything so I've ignored that.
>Maybe they fixed a bug I was counting on.
>So does anyone know why jpgs that were created with a gamma of 2.0 would
>be so light that they are almost invisible on Windows, and too dark on
>OS X? (Do jpgs even have a gamma? Maybe they sent me converted images.)
>Everything used to be fine until somewhere around LiveCode 6.x.
>Jacqueline Landman Gay         |     jacque at
>HyperActive Software           |
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