delete all white area in photshop.

[malcolm]

Hi i have a graphic of black spotchy paint on a white background, However i really need this to be on a trasparent backroung so i can overlay it on a photo. Using multiply is not an option because it effects my CMYK levels of the black by bring the the photo thru the splotchy paint. If I could just turn all the white areas into transparent it would be perfect. It is too complex to just magic wand as some parts are black 50 opacity.

I hope this makes sence

Mal

[Ovaltine]

Makes perfect sense.

There are probably other ways to do this (probably better ones), but I'd do a color range selection of the dark areas you definately want to be opaque. Then feather the selection (how mich will depend on the resolution of the pict), and duplicate that part of the selection. Leave the duplicated section normal, and do the multiply on the original "splotchy paint" layer. Sometimes I do a couple duplicated layers (varying the amount of black/grey I seltct with the color range) and mess with the opacity until it all blends nicely.

[urstwile]

Sometimes, rather than doing multiply, darken or color burn works well (I'm not sure what you're underlying photo looks like, however, so this might be dodgy). Color burn seems to work well, kind of allowing the lighter areas to multiply, while the darkest areas don't.

http://img140.imageshack.us/img140/2798/image34li.jpg

Or set the threshold of your magic wand down to 1 and give that a try. The default threshold might just be set to high, and so would grab parts that you don't want it to. You'll still need to feather the selection a bit.

Then use select similar to grab the other parts. It'll use the threshhold settings currently in your magic wand.

An image sample might be nice. I could probably steer you towards some other tricks. :)

[cjoe]

if you do a colour range select, save it as an alpha channel, and adjust the channel from there; levels etc. Then use the channel to create a mask.

[urstwile]

cjoe,

You and I appear to be on the same schedule. :)

[malcolm]

Thank guys, the threshhold almost did it. very close.:)

here is the graphic without multiply
http://i12.photobucket.com/albums/a244/wal000/intune14.gif
here it is with multiply
http://i12.photobucket.com/albums/a244/wal000/intune13.gif
Because of the opaque parts this was very hard. I did not want to use multiply because it was changing the clck where the image underlied.

Obviously when i did the brush strokes I would have been best not to keep my white brush layer and simply delete it when i decided to go with the simple black.

[urstwile]

Hmm, so you needed the black brush strokes to be visible on the right hand side of the image as black, but on the left side, where the MERC is, you needed those to show through as white? Seems like you could have fairly easily masked this for your final effect, unless I'm completely misunderstanding the final result you're looking for. :confused:

[Broacher]

For years I've used this plugin: simple, fast... FREE!

http://www.edesign.com/filters/

Might as well get the black one while you're at it.

[Ghastly]

Can I assume the black & white stuff is on its own layer? by going into layer properties and adjusting the 'blend if' sliders you can knock out blacks, whites & greys without having to worry about blending modes etc...though the net result of this is purely visual without doing further work (ie: the knocked out colours still exist on the layer, they just have zero opacity) you can fix this by creating a new layer...and merging it with the black & white stuff layer.

[Jason Fraker]

^I concur.

[urstwile]

^Me too. I was going to suggest that, but wasn't sure how to say it in English. :)

[Gromit801]

Clipping paths once you've selected the proper color.

[malcolm]

the white part of the merc part is a seperate layer an masked so it does not creat an issue
however I think Ghastly's option is the bomb!

thanks

[cjoe]

nice call ghastly. Coincidently Thirsty Merc did their video for Summertime at the Stockton sand dunes, which are two minutes drive from my house.