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    Photoshop - Terminology


    Posts : 9
    Join date : 2010-09-10

    Photoshop - Terminology

    Post by ConJurer on Tue Sep 21, 2010 1:43 am

    As requested. Will be updated whenever i'm free.

    Image Dimensions
    DPI/Resolution - Dots Per Inch, indicates number of pixels to be distributed over one physical inch. Print default is 300 dpi, screen default is 72 dpi.
    Image Size - Measured in pixels unless otherwise stated by the software you are using. Do not confuse this with dpi.
    note>>> image size is not affected by dpi digitally. dpi only determines the print quality. higher quality print inversely gives you smaller print size, while on the screen, the image size is digitally unaffected.
    Canvas Size - Think of it as size of your paper. Sizing down means cutting and throwing away part of your pic. Also true for sizing up. Canvas size does not affect scale.

    Channels - Basic colour information, also known as Red, Green, and Blue. Your primary colours separated into individual components, displaying only value in their own terms. Other than the 3 channels RGB, one other channel exists, which is called the Alpha channel.
    Mask/Alpha - Mask is also known as the Alpha, is handled by the Alpha Channel. Alpha channel uses float values (from 0 to 1) to determine the transparency of an image.

    Value - Any number in between, and including 0 to 1, used to determine the intensity of a colour. 0 = black , 1 = max (white if its on the grayscale chart).
    Hue - The combination of a maximum number of 2 channels by a certain ratio. Primary colours RGB and secondary colours CMY are some of the hues. Measured in degree.
    Saturation - Purity of hue in a colour. Measured in percentage.
    Colour - [Value + Hue + Saturation] = Colour
    Eg, Gray(0.5) Value + Magenta (Red:Blue = 1:1 or 300°) Hue + 50% Saturation = Dull Purple (RGB = 128, 64, 128)

    Blending Options - determines how 2 elements interact with each other in terms of digital colour math. Multiply, dodge, overlay, difference, etc.

    Vectors/Pen Tool/Paths
    Vectors/Splines/Path - Path is the term used in PS. We generally call them vectors or splines. These are curves plotted between 2 Anchor Points/Vertices.
    Anchor Points/Vertices - Points you plot around the image to draw splines. Comes with handles to determine the direction of the spline.
    Vector mask - Alpha using a vector-based bounded shape.
    note>>> vectors are mathematically scale independent, so no matter how you scale up or down a vector image, it still retains its quality. It draws lines using an equation rather than given constants.

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    Join date : 2009-09-21
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    Re: Photoshop - Terminology

    Post by Gin on Tue Sep 21, 2010 10:27 am

    *eyes glaze over* Wtf, I'm studying Computer Graphics now, and seeing all these terms is like a walk in the park XD

      Current date/time is Thu Oct 19, 2017 6:56 pm