How to go from bitmap to grayscale in photoshop?

[albabu46]

hey guys so i need to color a image i created in photoshop(using the paint scale) and it keeps telling me i need to convert the image from bitmap to grayscale. thanks guys! (im using photoshop CS3, i dont know if that matters for this or not i know it does to do other things) thanks!

[handrawn]

on the photoshop image menu select mode - then you should have the choice to select greyscale - after that, if you are colouring you will need to change it again to rgb [or index if you want limited colour, or cmyk if it is for printshop]

[Albacore]

Two methods I use: Under the Image Menu ---> Convert to Lab colour. --->If you have any layers bar "background" (get rid of that by dragging to trash before you convert to lab) then flatten the layers. ---> Once converted to Lab you will have 2 layers "Alpha a" & "Alpha b", delete "Alpha a" by dragging to trash can, this is done through Windows -- Channels, in the same palette window Channels delete Channel Alpha2, That just leaves the lightness channel which is renamed Alpha1 ---> Go back to the Image menu and go down to Mode then out to Grayscale.

The other method: This method we use the Channel Palette in RGB and we look at each of the thumbnails for each channel -->Red - Blue - Green. Now I always use the Red Channel for converting into the Grayscale but it will depend on your picture but never the Blue as it usually holds all the crappy parts of the file info. To save me typing all of the instructions out here is a link to a tutorial. http://www.photoshopessentials.com/p...olor-channels/

[gwpriester]

I'm moving this post to the Graphics forum.

Grayscale IS a bitmap. But it is a color space not an object or image.

[handrawn]

yes well, just to be confusing 'bitmap' is also what photoshop calls the colour space that is 100%black+100%white only, and is not anti-aliased

I took this to mean the OP had been working at pixel level and now wanted to convert to greyscale in order to add colour depth [albacore seems to have looked at it the other way round, going from colour to greyscale]

[gwpriester]

...and it keeps telling me i need to convert the image from bitmap to grayscale.

.

[handrawn]

exactly