I have seen this problem with .png files in the past. See the image.

I just converted the file to a .tga and the background showed up as white. I thought .tga files could store an alpha channel, but why does it show as white.

So I selected the white with the magic wand tool in PSP and after promoting the background to a  layer deleted the white. 

Then I saved it as a .png file and now the  the background shows in Poser as all white instead of the black as you see here.

Originally I had deleted the background and saved it as  a .png file and this image is the result. Does Paint Shop Pro save an invisible copy of the original file that I can not access?

Tom

If you can see the "channels" you should be able to fix the areas you need to. I know if Photoshop you can.

It's not really that tga doesn't hold an alpha...it does. And so does png. It's just that Poser has a hard time having all that in one file ;). I always go in and make a black and white from the channel. ;). Most of the time they're flipped opposite anyway and are white where they should be black and vice versa.

The preview in Poser is going to show areas of a mask as a color..even if it's transparent in reality and technically there's nothing there. Even if it looks sorta messy, if you look at the image on the main node, you're still getting trans where you should be ;).

Laurie

I used to make .jpg files with a black and white but the pixelation is pretty bad in a jpg. maybe I should just paint the background of a tree and make it black. Then still use  .png so there is no quality loss.

Maybe a different extention as  .png files are pretty heavy.

Any suggestions?

Tom

Both jpg and png are lossy file types, only png not quite as much. Your best bet is something like an uncompressed .tif, but of course they're huge. There's a sacrifice in file size for quality :). png is a good compromise.

Laurie

As I suspected. Was not aware .png was lossy though.

Thanks for the help!

Tom

FWIW, png's aren't totally lossy...if you save them at top quality they are for all points and purposes not lossy. They just CAN be lossy depending on how you save them. I'm a Photoshop user so I don't know how PSP handles them.

Laurie

PNG has non-patented completely lossless compression, as zip files also do - not a single bit is lost on recovery.

PS: Oh wait - are you perhaps thinking of PNG 8 - that uses a palette of only 256 colors? Yes that could be termed "lossy" but it's not usually what people mean by lossy.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

 I don't know what PSP uses BB ;). I know ya can do both in PS..I always use PNG 24 which I use a lot ;).

Laurie

By default, PNG images saved from PaintShop Pro use lossless compression. If I save to PNG, it's because I want pixel perfect quality with a reasonable file size, so I've never had occasion to play with with the settings, or the PNG Export Optimiser, and it may be that lossy compression is possible. 

 

Lossy compression is not possible. PNG hasn't got one. However, some apps intentionally do various forms of preprocessing to make the data more compressible. This has nothing to do with PNG, per se.

There is one particular app called ImageAlpha that has this behavior as its only reason for existence - to make PNG files really small. It does this by blurring, quantizing colors, and using dithering against a custom color palette with 8-bit lookup. None of these techniques are part of the PNG 24 file format.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

It doesn't help our understanding when tutorials and explanatory articles you find on the web are written by people willing to twist the meanings of words, or they actually don't know what they're talking about.

Here is a fascinating one because it sets up the bogus idea of lossy png and then, in the second paragraph, acknowledges that there is no such thing:

http://www.websiteoptimization.com/speed/tweak/lossy/

First paragraph: "Lossy compression is a good way to squeeze extra bytes out of your GIFs and PNGs"

Second paragraph: "Lossy compression is actually a misnomer for GIFs and PNGs. The compression algorithms used in GIFs and PNGs (LZW and Deflate) are lossless, so there is no loss of data when compressing these palette-based formats. The lossiness comes in when a graphics program automatically prefilters or alters the image to compress more efficiently. The loss of data occurs in the prefiltering phase by  increasing redundant patterns along scan lines to improve compression (see Figure 2). Lossy compression has become a shorthand, yet somewhat misleading, phrase for this process."

 

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)

I just had a fiddle with PSP's so-called PNG optimiser - for the first time ever - and I see it does offer palette-based colours. Pre-compression loss, if you prefer to call it that. You can also change the transparency method (which doesn't appear to change file size), choose interlaced (which makes it bigger), and convert to greyscale.