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View Full Version : Image Map with transparency - White halo?



dmack
12-05-2007, 02:55 PM
Hi All,

I'm surfacing an aircraft (Avro Lancaster) and need to add some grime to it. I need to add some grime that is partly black (sooty) and partly white (lead deposits). So, I've painted it in photoshop against a transparent background. Now when I apply that map in LW, it does it BUT where I've used the airbrush you can see a white halo, instead of the black gradually fading to transparent. You can see in the image editor that it automatically places the transparent image against white. So, whilst it obeys the alpha channel to a degree, anywhere between 0% transparent and 100% transparent gets an ugly white halo.

Any help greatly appreciated. I'm really stumped on this one!

Hopefully a little down the line I'll have some results to show you guys!

dmack
12-05-2007, 03:14 PM
Aha! It doesn't happen with PNGs! PNG's also have a much much smaller disk space requirement (I know same amount of mem when rendering). SO...Another question before I get too excited! Are there any issues with PNGs in Lightwave?

IMI
12-05-2007, 03:28 PM
Were you using a .tif? before? I've had some problems with tif's. No problems that I know of with PNG's, and PSD files work well too.

dmack
12-06-2007, 11:03 AM
I tried 32bit tgas and 32bit psds - both created the ugly halo - PNG's seem like a golden format! They work, take less disk space and show up as thumbnails in windows!

Lightwolf
12-06-2007, 01:02 PM
I tried 32bit tgas and 32bit psds - both created the ugly halo - PNG's seem like a golden format!
Blame Photoshop. It depends on how Photoshop interprets the RGB in conjunction with the alpha when saving.

PNG is cool though.

Cheers,
Mike

Red_Oddity
12-07-2007, 02:38 AM
I also noticed that when you save a file which conatins a single layer (with transparency) photoshop just adds a white background to it.
Best thing is to save a file that has a completely filled black image as the bottom layer and do the transparancy as an alpha layer...offcourse, being Photosop, this also gives a meriad of problems as all file import and exporters in photoshops behave differently (wow Adobe, thank you for your 1500 euro bloatware with bugs and issues that have been known since version 5, we're at version what, 9 by now?)

tcvivrant
12-07-2007, 03:00 PM
I also noticed that when you save a file which conatins a single layer (with transparency) photoshop just adds a white background to it.
Best thing is to save a file that has a completely filled black image as the bottom layer and do the transparancy as an alpha layer...offcourse, being Photosop, this also gives a meriad of problems as all file import and exporters in photoshops behave differently (wow Adobe, thank you for your 1500 euro bloatware with bugs and issues that have been known since version 5, we're at version what, 9 by now?)

10...lol

Red_Oddity
12-07-2007, 06:59 PM
Yeah, i lost count after the stupid CS branding, i still wonder why i keep paying these money grubbing lowlifes for every darn update.