How do you change a white to transparent?

[Mandy]

I have a simple thing to do and its driving me crazy. I have a black and white image which I have changed to bitmap and now I want to change all the white to transparent so that I can drop in different coloured layers in the backround. I know there is a simple way to do this but have just forgotten. Can anyone help??

 

[iDad]

select your white area >copy>delete>paste it back>you have separate layers go to layer palette >opacity levels lower transparency on new layer save as a.gif or .png done.

 

[iDad]

btw be sure to delete background layer first

 

[Mandy]

In my image there are large areas of black with white dots and visa versa so to select each dot will be a huge pain. Is there no way that I can say just replace all white with transparent?

 

[iDad]

depends on picture you can try using magic wand, select your white area then right click it > drop down menu>select similar you can try that then transform selection in drop down if it's not good enough

 

[Mandy]

Thankyou so much. I got it done with the select similar.

 

[iDad]

great glad it helped....... good luck!