fixed : quickly create a printable grayscale picture from a color photo using Preview.app

Question :

I often have color pictures (like photos) that I would like to print in grayscale, but I don’t have a grayscale printer.

What is the simplest way to do so ?

 

Answer :

Having a color printer is great, and the easiest way to print grayscale pictures is to just select the grayscale-option before printing :

  • open the picture (ussually a .jpg) in Preview.app
  • in the top-bar, go to File and select Print from the pulldown list ; or press the [CMD]+[P] key-combo on your keyboard
  • in the pulldown window that opens, click on Preview and select Graphics from the pulldown menu
  • then, at Color Mode, select “Grayscale” (instead of “Color”)
  • then click the Print-button and see what comes out of your printer
  • Note that if you would make a PDF now, that it’s not going to be a grayscale picture…

Sometimes this will do just fine, but often that isn’t enough, and you will need to do a few extra steps to get an acceptable result out of your printer :

  • open the picture (usually a .jpg) in Preview.app
  • click on the “Show Markup toolbar”-button (the circle with the pen-point in it, just left of the Search-bar top-right)
  • first, crop the image if needed :
    • then, click on the DashedSquare-icon (top-left) and select the “Rectangular Selection” option
    • on the picture, select the area you want to use (click the top-left of the envisioned area, than botom-right) and the selection area will be displayed
    • if you need to, adjust the selection area by dragging it’s edges
    • then, in the top-bar, go to Tools and select Crop from the pulldown list ; or type the [CMD]+[K] key-combo on your keyboard
    • now the picture will be croped to the smaller ‘selection only’ size
  • then, in the top-bar, go to Tools and select Adjust Color from the pulldown list ; or type the [CMD]+[ALT]+[C] key combo on your keyboard
  • in the AdjusColor-window that opens there is a ‘histogram’ (a picture with red/green/blue (a.k.a. RGB) graphs) with an AutoLevels-button, a list of 9 sliders and a ResetAll-button below it
  • attached to the base of the histogram, there are 3 slider-pointers (a.k.a. histogram-sliders)
  • set the middle histogram-slider lower (a little to the left)
  • then set the right histogram-slider lower (a little to the left)
  • then set the Exposure-slider higher (a little to the right)
  • set the Contrast-slider higher (a little to the right)
  • set the Sepia-slider in the middle
  • set the Sharpness-slider higher (a little to the right)
  • see if the (color) picture’s look is now clearer …if not go back and adjust the sliders until it is a brighter picture with more detail
  • then, in the top-bar, go to File and select Print from the pulldown list ; or press the [CMD]+[P] key-combo on your keyboard
  • in the pulldown window that opens, click on Preview and select Graphics from the pulldown menu
  • then, at Color Mode, select “Grayscale” (instead of “Color”)
  • then click the Print-button

that’s it !

Note : if you would make a PDF now, that it’s going to be a color-picture, not a grayscale picture… if you need a grayscale picture digitally, you will need to use Photoshop  or something similar…

Important extra note : once the picture is a PDF, you can no longer adjust the colors

enjoy 😉

 

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tip : quickly cut-out part of a picture in OSX

Question :

I have a nice picture I want to use in a presentation, but I don’t want the entire picture, just part of it.

Is there an easy way to cut the desired piece out ?

…even if I don’t have Photoshop ?

Answer :

Even if you don’t have Photoshop, cutting out part of a picture for (re)use in PowerPoint, Keynote, Word, Pages, your website, LinkedIn, FaceBook, etc. is very easy on your Mac :

1- open the picture in Preview app (usually that would only require you to double-click on the picture’s icon)

2- click on the Image-button (Edit button)

3- in the Editing-toolbar that appears, click on the Image-button (Selection button)

4- now the + (Plus sign) appears, so : click on one corner of the part of the picture you want to select and drag to the opposite corner [ you can do this rather ‘roughly’ ]

5- then the selection area appears [ normally a rectangle with dots in the corners and on the middle of the side ] ; drag the dots so, that the selection area exactly fits the part of the picture that you want to take out

6- then press the ‘Copy key-combo’ (CMD + C)

7- now choose “New From Clipboard” from the “File”-menu, or press the ‘New key-combo’ (CMD + N), and you will get a new window with only your ‘cut-out part’ in it

8- if that looks as you envisioned it, choose “Save” from the “File”-menu, or press the ‘Save key-combo’ (CMD + S), and save the cut-out picture as a JPEG or PNG (or TIFF)

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