Turn white pixels into transparent pixels?

[Stix_Hart]

This is probably really basic but...  I'm a printer and only really use Photoshop for changing RGB to CMYK, clear cutting (with Vertus fluid mask) and things like that.  However a lot of the photos I have to clear cut have been done already but not saved (or given to me to use) with the transparency still there.  Is there some easy way to turn all the white pixels into transparency?  Obviously you'd have to mask any white pixels in the image you wanted to keep.  A sample is attached.

[Phos_four_dots]

Have a look at the following link:

http://forums.adobe.com/thread/370989?tstart=0

Unfortunately, with the forum changeover we haven't been given easy navigation to this sub-forum...The Photoshop Lounge Resource Repository.

[Andrei Doubrovski · Accepted solution]

Steve,

Try the following.

1. Covert the Background to ordinary layer (Layer > New > Layer from Background)

2. Select the white area with the Magic Wand or Quick Selection tool

3. Mask the selected area (Layer > Layer Mask > Hide Selection)

4. Export the image  (File > Save for Web) to GIF or PNG format:

[Phos_four_dots]

Nice stair-steppy edges, Andrei!

Can you post an extended tutorial for getting that effect?

[Zeno Bokor]

can't help it when it's 1bit transparency with non-straight edges

[Phos_four_dots]

Zeno Bokor wrote:

can't help it when it's 1bit transparency with non-straight edges

Stupid GIFs, be more PiNG-y!

Steve never said he needed GIFs (only that he needed sorrounding white pixels turned transparent), and he also said he was mostly a print guy, so GIF would be about the last format I'd use in that capacity.

There's to much info missing about the final destination of the photos he's working on to assume which format-with-transparency would be best.

[Stix_Hart]

Thanks heaps for your help guys! Andrei's method works great for what I'm doing, and I'm playing around with that plugin now Phos, looks promising too.

I save images as psd native files for when I'm printing (they get placed in Indesign further down the track) and use PNGs if I supply them to the customer for their use in Office or similar. Are these the correct formats to use?

What other widely used program has such brilliant forums (the users & answers, not the ease of use!) as Adobe Creative Suite? <Rhetorical question

[Zeno Bokor]

for printing purposes you could try using clipping paths.

http://help.adobe.com/en_US/Photoshop/11.0/WSfd1234e1c4b69f30ea53e41001031ab64-7713a.html

[jethrobot]

Don't forget to use Layer >> Matting >> Remove White Matte. One of Adobe's goals with the release of CS3 was to make it good at compositing, so definitely don't forget these new features.