Advice on Sizing in Photoshop for Creating Decals...

[Laconic]

Hello All!

 

I have created my first model mesh and I'm happy with it. I created the model in centimeter measures, and now I'm ready to add my decals. I plan to create the decals in Photoshop. Here are my questions:

 

1) If my model is 1000 cm tall according to the rulers in A:M, should I also start with a 1000 cm file in Photoshop, so that when I'm decalling, the proportions are correct? (Ignore the fact that I might only decal some parts. I just want to know if the measurements in Photoshop should be the same as in A:M).

 

2) If the answer above is yes, what should the pixel density/resolution of the file in Photoshop be? (300 dpi? 72 dpi?)

 

3) Finally, is the .tga format the correct format to save into, in Photoshop, for importing into A:M?

 

Thanks for your help!

 

Tim

[KenH]

Hey.

 

1) Not exactly sure if the two systems line up, but it all depends on how close you want to get to your model. A good starting point is 1024px. That's another point....deal in pixels not cms.

 

2) As high as possible. Though a monitor can't display more than 72dpi. Another starting point is 100dpi.

 

3) Yes...for highest quality. It also accepts jpeg, png, etc.

 

These are just guides. You should do some render tests to see how large they should be.

[luckbat]

1) If my model is 1000 cm tall according to the rulers in A:M, should I also start with a 1000 cm file in Photoshop, so that when I'm decalling, the proportions are correct?

No. Like Ken said, only the dimensions in pixels matter. The "correct" resolution of a decal depends on a spectrum of factors, including:

* The resolution of the final image

* How close the model is to the camera

* How much detail is in the decal

* What rendering method is being used

* Your lighting scheme

* Motion blur/Depth of field

...and many more!

 

The bottom line is, start with low-res textures and do some test renders. If you notice some pixelation, swap in some larger textures. Keep increasing the resolution of any texture that isn't smooth enough for you until it renders acceptably.

 

So why not just use 32768x32768 textures for everything? Because it'll slow your project down to a crawl. Try to use the lowest-res textures you can get away with. Some people even maintain multiple versions of their models--one for general use, and one for closeups.

 

2) If the answer above is yes, what should the pixel density/resolution of the file in Photoshop be? (300 dpi? 72 dpi?)

DPI--dots per inch--is a print term which is meaningless for screen images. Use "resolution" instead.

 

3) Finally, is the .tga format the correct format to save into, in Photoshop, for importing into A:M?

Yes. Don't use JPEG; the compression artifacts will ruin the texture.

[MMZ_TimeLord]

Yes. Don't use JPEG; the compression artifacts will ruin the texture.

 

You are partially right luckbat. You will only see artifacts on JPEG images that have quality settings on anything but 100%. I always set my quality to the highest when dealing with photoshop or paintshop pro.

 

If you turn the compression up, you will get more artifacts, that's the trade-off with JPEG. It's the same as using a lower quality setting on a codec for a movie file (MOV or AVI). The lower your quality, the worse the artifacts.

 

Again, if you are never close enough to see artifacts a slight compression may be acceptable.

 

All the textures I did for my Project Earth were saved in JPEG, but the compression was set on 100% quality (lossless) so my JPEGs were a bit large but WAY smaller than BMP or TGA files.

[KenH]

I think even a 100% quality jpeg is less quality than the targa or bmp it came from. Hence the lower MB.

[MMZ_TimeLord]

Check this out...

 

Specifically this part ( I realize this is an older FAQ, but it is still relevant. )

 

It's worth repeating that cranking a regular JPEG implementation up to its

maximum quality setting *does not* get you lossless storage; even at the

highest possible quality setting, baseline JPEG is lossy because it is

subject to roundoff errors in various calculations. Roundoff errors alone

are nearly always too small to be seen, but they will accumulate if you put

the image through multiple cycles of compression (see section 10).

 

Many implementations won't even let you get to the maximum possible setting,

because it's such an inefficient way to use regular JPEG. With the IJG JPEG

software, for example, you have to not only select "quality 100" but also

turn off chroma downsampling to minimize loss of information. The resulting

files are far larger and of only fractionally better quality than files

generated at more reasonable settings. And they're still slightly lossy!

If you really need lossless storage, don't try to approximate it with

regular JPEG.

And another... JPEG

 

With all of that said, I stand corrected. PNG or TGA would probably be the way to go if you want or need a truely 'lossless' compression.

 

The images I was working with on 'Project Earth' were very high resolution and downsized from even higher resolution TGA images, therefore I felt that maximum quality JPEGs would do just fine.

[Laconic]

Thanks, All!

 

Your help is much appreciated!

 

Cheers!