Decal color problem

[DJBREIT]

For the last day or so I have been trying to render a simple scene with a decal. But I cannot get the decal to render correctly.

origenal

render

[Rodney]

Need more information...

 

Are you rendering out this Decal in a Choreography, Action or Model window?

 

The same issue may be behind the problem so I'll offer the following:

If you are in a Choreography window consider the lights you have shining on the decal.

The Modeling window has a default lighting setup that can alter the image also.

 

On a duplicate version of your Chor (don't do this on your original) delete the default Three Light Setup and render again.

If anything the decal should be darker than your targeted color.

 

There are a few ways to alter the color/brightness of a decal. One of the methods I like to use is to add a second stamp on the decal to color the brightness. This way you can match the target color perfectly in any lighting condition without adjusting your lights.

[robcat2075]

The washed out color?

 

Is there a light shining on the surface the decal is applied to? I guess there is because you're using AO for the drop shadow? That may be it.

[DJBREIT]

Need more information...

 

Are you rendering out this Decal in a Choreography, Action or Model window?

 

It was happening in all the windows.

 

After testing with some other formats (TGA and jpeg) in the image section it became apparent A:M has a problem with (PNG files colors) I will add it to the report section.

[Rodney]

I've found that when in doubt TGAs are still be best of the best image format to work with for images/decals.

I don't often use JPG, etc. for production work because they don't support Alpha Channels.

 

I'd be tempted to standardize on .EXR but I'm so use to TGAs and their compatibility with other programs

TGA has a solid reputation and time tested foundation but can be degraded to PNG for online viewing as necessary.

There are a few things with PNG that still need to be worked out.

Whereas TGA is ideal for compositing, PNG's primary usage is for browsers.

[DJBREIT]

At least I know now.

Thanks

It looks a lot better. Now I can work out the rest of the scene.

[HomeSlice]

After testing with some other formats (TGA and jpeg) in the image section it became apparent A:M has a problem with (PNG files colors) I will add it to the report section.

Did you save the png out of Photoshop? If you did, Yves Poissant addressed this a couple of years ago. It seems Photoshop (and perhaps other programs) sets the gamma of png images in some strange way. I think on Windows, the gamma is set to 2.2. Yves suggested removing the gamma information altogether using a program like PngCrush ( http://pmt.sourceforge.net/pngcrush/ ).

 

You can also use IrfanView to gamma correct a png image. Open the image in IrfanView and go to Image > Color Corrections. Then set "Gamma Correction" to 1.00.

You can also Batch correct a bunch of png images at once. Open IrfanView and go to Fle > batch Conversion. For "Output Format", choose "png". Then hit the "Advanced" button. Then check the box for "Gamma Correction" and enter a value.

http://www.irfanview.com/

 

The problem is more widespread in the web browser arena. Here is a brief overview of the problem web browsers have with correctly rendering png images. http://morris-photographics.com/photoshop/.../png-gamma.html

[Rodney]

Thanks for that Holmes, the resources you've linked to explain the problem nicely.

It's a shame really. I'm a fan of the PNG format and would love to use it (and PNGs animated formats) more often.