Digital Earthworks RGB Mask alpha channel problem (reflex)

[orakix]

So im using photoshop cs2 and digital earthworks v0.8.1.8 and no matter what I do to the psd file the track is still 100% wet. I do have my alpha channel pure black. I've tried with gray, white, and everything in between. I've tried having it in a different file then my Height map. changed layer order. Changed from using black for my track path to all the different colors. Tried hiding the alpha channel, showing it and no matter what I do it is still 100% wet. I did get it to be black, or dry, once but that was when I had a completely blank .psd. Soon as I started painting color into it, it went right back to white/wet. This is my first and reflex track however I used to make tracks for mcm2 a looooong time ago. If there is any additional info you need to help solve this problem just let me know and I will get it for you asap. Thank you in advance.
OrakiX

[JamieT]

Hi orakix,

Are you importing the .psd directly into Digital Earthworks or are you saving the RGB Mask as a .bmp first, before you import?  Importing the .psd should not give you this problem, so it's very strange why this is happening to your .psd.  However, if you are saving it as a .bmp first, and then using that to import, you may see this problem.

It can happen because you have previously saved the .bmp in the past without an alpha channel.  Even if you add an alpha channel later, and you save over the previous file, Photoshop can still think that you are saving a file with no alpha channel (24-bit Bitmap).  To solve this, you should "File > Save As..."  This will then create a new file which will save the alpha channel (creating a 32-bit Bitmap).

The wet look will always comes from the alpha channel in the RGB Mask, so that is the only one you need to work on.  Hiding the alpha channel should not make any difference either.

So hopefully if you go "Save As.." it will create a new file which should save the alpha information for your .psd or .bmp.  I hope that helps!  Let us know how you get on.

[orakix]

Unfortunately I am doing it straight from the psd. The tutorial I was using stated to put my dpi at 4000 which my Photoshop will not save a bmp with that high of a resolution. (At least I believe that's why. Either way it will not let me save as anything but psd) The very first thing I do when making the file is make a blank layer, add the alpha channel, and save. If I import at this point it works just fine but of coarse, the track is one solid color at this point but at least its dry. If I add any solid color to the mask it makes the alpha go white (in digital earthworks anyway, in Photoshop it still shows a black alpha) I've even tried using a older version of earthworks and I ran into the same problem. Could it be that Photoshop cs2 just saves its files differently then other versions and that's why I'm having issues?

[JamieT]

I assume you're following AL167's tutorial where he has his resolution set to 4000 pixels per cm..  As far as I'm aware, resolution settings are only needed for when you're printing something out on paper.  You don't need to worry about it when what you're creating is digital content.  I use 96 pixels per inch in Photoshop 7.

Not being able to save in other formats is a big issue, so something's definitely wrong there.  If it is as you think, related to your resolution, I suggest changing it to the same as what I have.  I'd put money the problem being something to do with how Photoshop is saving the files, rather than a problem with Digital Earthworks.

If changing the resolution doesn't work, there could be something else wrong with Photoshop... An alternative is to use a program called GIMP http://www.gimp.org
It can do pretty much the same thing as what Photoshop does.

Hope that helps!  Once again, let us know how you get on!


Edit:  I also notice AL167 has his channels set to 16-bit per channel.  This is most likely the reason why you can't save files in a different format.  8-bit per channel is what you should use.

[orakix]

Yes!!!! That worked. I don't know if it was the dpi or the bit because I changed both and then tried it but either way.... IT WORKED! Thank you so much. I appreciate the help.

[al167]

yeah its gotta be 16 bit as 32 bit doesn't save the alpha

[JamieT]

Glad to help you out orakix!  It was definitely the bits per channel that was preventing you from saving in another format, and also must have messed up whatever was going on with the alpha channel.


I think you might be getting confused Al,

You had your image set to 16-bit per channel.  Digital Earthworks will only read images which are 8 bit per channel.  Even though you imported an image which was 16-bit per channel, it will automatically read it as 8-bit per channel.  Or on the other hand, your version of photoshop may have just saved it as 8-bit per channel without you realising, depending on which format you saved.

The amount of bits per channel determines what "bit" your image will be.  For example, an image that uses 8 bits per channel in the RGB (Red, Green & Blue) channels will result in a 24-bit image.  Adding an Alpha channel to that, will result in a 32-bit image.

The bits per channel is all to do with how many colours there can be in an image.  8-bit per channel means that there are 256 variations of colour in each channel.  This is because 2 to the power of 8 (bits) = 256.  You will notice in photoshop in the colour picker that there are values in the R,G,B boxes ranging from 0 to 255.  0 being the 1st, 255 being the 256th.

The colour picker in Photoshop and every other program I've used, will only pick colours that are 8 bit per channel.  Over the three channels (RGB) this will results in over 16 million colours, 256 x 256 x 256.  The human eye can't even detect that many colours, so for most things you'll do on a computer, 8 bits per channel is more than enough.  I think 16 bits per channel is probably used by photographers maybe...

The only time I've ever used an image with 16 bits per channel, is with Greyscale images that are exported from a 3D terrain editor.