Photoshop Question

Discussion in 'Digital Photography' started by Apple Corps, Oct 21, 2008.

  1. Apple Corps macrumors 68020

    Joined:
    Apr 26, 2003
    Location:
    California
    #1
    I have a photo of an object that is on a black background. I so want to outline the object and "cut" the black ground away. I've tried using the magnetic lasso tool but am finding it very difficult to outline the object precisely.

    Am I using the proper tool? Yes, I am a beginner with CS3 - can you tell :eek:
     
  2. Pieface macrumors newbie

    Joined:
    Sep 14, 2008
    #2
    If it is completely black, then maybe just try a background eraser tool? Or just take your time with the normal lasso tool?
     
  3. FrankieTDouglas macrumors 65816

    Joined:
    Mar 10, 2005
    #3
    What is the object?

    You can try a Select: Color Range and select the black, then mask that out. Use a fine brush to clean up any extra remnants on the mask.
     
  4. Apple Corps thread starter macrumors 68020

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    Apr 26, 2003
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    California
    #4
    Yes totally black. I'll try to find he background eraser and report back.
     
  5. 66217 Guest

    Joined:
    Jan 30, 2006
    #5
    In those cases (tho showing us the photo could help) I use the Quick Selection Tool. Then I modify the selection to make it look natural.
     
  6. ChrisA macrumors G4

    Joined:
    Jan 5, 2006
    Location:
    Redondo Beach, California
    #6
    You are going at this correctly. Your pproblem is that you are expecting to much of the tool. To make the selection first use the tool. It will do a decent job by itself but then you have to refine it. Zoom way in close and then add and remove parts of the selection. You can spend a lot of time of this but that is just the way it is. You canuse any of the selection tools to refine the selection all of them have modes to add or to remove selection.

    One trick is to select the black background as the first step then to "invert" the selection and then refine that.

    Finally when you are done. Zoom in to 100% and give it a good look then find the menu pick Refine Selection and maybe shrink it by 1/2 pixel or passably feather the selection slightly. It all depends on why

    Selecting objects in Photoshop is a skill you build up over time and is one of the most impotent and basic photoshop skills to develop. It is not easy. I think your only problem is that you are expecting to much of the automated tool. It's easy to spend 30 minutes getting a selection "just perfect". In most Photoshop books making selections of a full chapter to itself
     
  7. Apple Corps thread starter macrumors 68020

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    California
    #7
    It is a photo of the earth against pitch black space. How do I mask the black out - the select worked well - very nice active circle around the image I want :)
     
  8. Apple Corps thread starter macrumors 68020

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    Apr 26, 2003
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    California
    #8
    ChrisA - that helps - this is very tedious. I am using a trackball and it is testing my hand / eye coordination.

    It is so clear that I need to purchase a tutorial book on this software. The Adobe on-line tutorials assume you know more than I do - not very helpful.
     
  9. Apple Corps thread starter macrumors 68020

    Joined:
    Apr 26, 2003
    Location:
    California
    #9
    Frankie - The globe (the part I want to have w/o a background) has a dotted line active around it. What are the next steps to "mask the black out"?

    I sure would not want to do this for a living 8 hours a day
     
  10. vigorblade macrumors member

    Joined:
    Jul 6, 2008
    Location:
    New York, NY
    #10
    Not sure if you already found your answer, but if you have the area you want to keep selected. The next step, if you don't have a second layer you should make one (You can use this layer for whatever you want to use to replace the black) after that make sure you have the earth layer selected and click the "add layer mask" button at the bottom of your layers palette.

    Hope that helps.
     
  11. FrankieTDouglas macrumors 65816

    Joined:
    Mar 10, 2005
    #11
    Yep, exactly. Make sure your image is unlocked in the layers palette. When the black sky is selected, add a layer mask. Go to Layer: Layer Mask: Hide Selection. When you click that, a box should appear next to your image in the layers palette. It will resemble a black and white version of your image. Whatever is black in that box (the one on the right) will be hidden and whatever is white will be visible.

    It's a bit to get your head around, but if you use a white paintbrush on that side box, it will reveal elements in your image. If you use a black paintbrush, it will hide elements in your image. This is a way to hide the sky while keeping the earth.

    Check out the attached image. I forgot to unlock it at first and did it later on, but for you, first thing to do is double click the layer and select "Ok." This will unlock it. Also, the fourth image is just me goofing around in the layer mask, so you can see how brushing in the mask alters the image you see.
     

    Attached Files:

  12. Apple Corps thread starter macrumors 68020

    Joined:
    Apr 26, 2003
    Location:
    California
    #12
    vigorblade and Frankie - thanks much - I'll get on it in the morning.

    BTW - that is the exact image I'm working with.

    So much to learn :rolleyes:
     
  13. jv-iphone macrumors newbie

    Joined:
    Jun 29, 2007
    #13
    an even simpler way to do this is.. And this works great if you want to remove a black background from an object,

    make sure your image is on a separate layer not the background, double click on the layer, it should open up layer style, you should see blending options, go to the bottom of the menu where it says This Layer under blend if - drag the black slider towards the right and the black background should disappear

    I know you can also use blending modes to remove white backgrounds using multiply in the layers palette that is what I do for objects with a white background

    Everything in photoshop revolves around layers a great book I have bought is called Layers - the complete guide to photoshop by Matt Kloskowsi, great for beginners or advanced users and everything about layers you will need..
     

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