GIMP Layer Blending Modes Explained In Detail Here
As well as discovering all aspects of Layers, this comprehensive GIMP (GNU) tutorial will teach you how to build a simple five-layered image. To work along, you are welcome to download my Four Transparent Beer Glass Images Here. Unzip the file and open the contents onto GIMP’s workspace. Then Link Here to lean how to arrange the Four Beer Glass Images into a Four-layered Image.
Ready-made Five-layered Beer Image File Download
If you prefer, you can skip the Arrange Layers step, and download my five-layered Beer Glass (including a single Transparent Layer) File Here. If you are utilising my pre-made
Five-layered Beer Glass Image, then Link Here to proceed to the start of my Understand Layers Tutorial.
My Other GIMP Layers/Blending Mode Tutorials
Understand GIMP’s Workspace
Blend Modes Explained - (With Mini Tutorial) Here - Beginners
Create A Transparent Layer & Fill It With Either A Solid Colour, Pattern Or A Gradient
Table Of Contents
Mask Layers - Intermediate
Deleting Layers - Beginners
Additional Panels - Beginners
Renaming Layers - Beginners
Duplicate A Layer - Beginners
Merge Down Layers - Beginners
Semi-Flatten A Layer - Beginners
A Layers Lesson - Beginners Plus
Toggle Layer Visibility - Beginners
The Anchor Layer Tab - Beginners
Changing Layer Orders - Beginners
Linking Layers Together - Beginners
Lowering Layer Opacities - Beginners
Expand The Layers Palette - Beginners
Reposition A Layer’s Object - Beginners
Accessing The Layers Palette - Beginners
The Lock Alpha Channel Tab - Beginners
Display GIMP’s Layers Palette - Beginners
Changing Layer Blending Modes - Beginners
Lower Or Raise An Active Layer - Beginners
Create A New Transparent Layer - Beginners
Merge (Visible) - Or Flatten Layers - Beginners
Quickly Scroll/Change Blending Modes - Beginners
Utilise The Layer Palette’s Vertical Scroll Bar - Beginners
Copy And Paste (Create A Four-layered Image) - Beginners
Adding An Alpha Channel To “Unlock” A Layer - Beginners
Fill A Layer With Colour, A Gradient Or A Pattern - Beginners
Applying Drop Or Perspective Shadows To Transparent Objects - Beginners
Open The Four Beer Objects (For This Layers Tutorial) Onto GIMP’s Workspace
Understanding Layers is fundamental to being able to produce sophisticated work within GIMP. They are the most essential feature it offers, and once the basics are understood - getting started is quite straight forward. After you have worked with Layers a few times, the more advanced features - such as Layer Masks, and Linking Layers, will fall into place.
Once you take your first step, you will never look back!
You may find it helpful to print this 50 page tutorial, please read my Printing Tips Here.
For most simple image retouches and corrections, you do not have to add any Layers; however, it is generally a good habit to Duplicate the Layer (by right-clicking the Layer in the Layers Palette and choosing Duplicate Layer from the subsequent drop-down list), before applying actions such as the photograph correction commands. By applying any changes to the Duplicated Layer, you will always preserve the original image on its own Layer. When you intend to do more complex work; such as add or remove elements; - create photo compositions, or add text and other effects - it’s good practise to utilise Layers for these tasks.
What Is A Layer?
When creating Layers, each Layer that you add begins as a transparent sheet over the Background Layer; as you add brush strokes, vector objects or text - you cover up parts of the Background Layer. Transparent parts allow you to see through to underlying Layers. You can stack up multiple Layers to create whatever effect you like - such as artistic compositions, collages - or complex illustrations.
The following (Photoshop Pen Tool) Vector Illustration Of My Dog Sacha Has Over 800 Layers
You can quickly Undo a step at any time by pressing Ctrl then Z. Alternatively, click a previous Undo History snapshot - Windows then Dockable Dialogues then click Undo History. In addition, to Zoom in (or Zoom out) of your image; from the top menu, choose View then select a Zoom Tool from the subsequent drop-down list.
1/ Open The Four Beer Glass Images Onto GIMP’s Workspace
As an alternative to choosing File and Open and then pressing Ctrl to highlight all four Beer Image and then clicking the Open Image dialogue box’s Open tab: you may find it easier to drag the Start Images onto Elements’ workspace. You can do this by opening the Beer Images’ Folder, and then minimising the Folder’s Workspace. To minimise the Folder’s Workspace, click its top-right menu’s Restore Down tab.
Then navigate to and open GIMP’s Workspace: and then navigate to the Beer Images’ Minimised Folder. The Beer Images’ Minimised Folder will then appear over GIMP’s workspace, and you can then press Ctrl and simultaneously left-click to highlight all four Beer Glass Files. Now, left-click over a highlighted file - and then drag the highlighted files onto GIMP’s workspace - as illustrated below.
Now, arrange the images as illustrated below, by left-clicking over each image’s top
menu-bar, and then dragging them into position.
Then from the top menu, choose File and then choose New. And from the subsequent Create a New Image dialogue box, set the following Fill with (Transparency) settings, and then click OK.
Now, arrange your the Four Beer Glasses and the Transparent Image over your workspace - as illustrated below. I demonstrate how to rearrange your workspace in the next step.
Ready-made Five-layered Beer Image File Download
If you prefer, you can skip the following Arrange Layers step, and download my
Five-layered Beer Glass (With A Transparent Layer) File Here. If you are utilising my
pre-made Five-layered Beer Glass Image - then Link Here to proceed to the start of my Understanding Layers tutorial.
2/ Rearrange The Beer Images On GIMP’s Workspace
Rearranging the workspace can be a little tricky. You’ll need to activate each image’s respective tab - as illustrated below. I find the best way to do this is to activate the Base Layer’s Image, and then activate and arrange the First Beer Image, and then activate and arrange the Second Beer Image, and then activate and arrange the Third Beer Image, and then activate and arrange the Fourth Beer Image.
After you have repeated this workspace technique a couple of times, the procedure will fall into place.
Now you have organised GIMP’s workspace, it’s time to create a four-layered image: therefore, activate one of the Beer Glass Image’s by left-clicking its top men-bar. And then from the image’s top menu, choose Edit and then choose Copy.
Now, activate the Transparent Image by left-clicking its top menu-bar. And then from the Transparent Image’s top menu, choose Edit and then choose Paste As and then choose New Layer - as illustrated below.
Congratulations, you have pasted your choice of Beer Image into the Transparent Document - as illustrated below.
Now you have Pasted the first Beer Image onto the Transparent Image, first activate and then close the original Beer Image - File then Close - as illustrated below.
Now, repeat the previous instructions. You are looking to activate, and then Copy and Paste the Second, then the Third and then the Fourth Beer Images onto the larger Transparent Image. After the Second, the Third, and the Fourth Beer Images have been Pasted - remember to close the original beer images.
After you have completed this, Maximise your Four-layered Image by left-clicking its
Top-right Menu’s Maximise tab - as illustrated below.
Then activate the left-side Toolbox’s Move Tool.
And separate your Four Beer Images by left-clicking and dragging them to alternative positions.
Now is a good time to save your Layered image as a GIMP XCF File.
4/ Display GIMP’s Layers Palette
From GIMP’s top menu, choose Windows then choose Dockable Dialogues: - and then click Layers - Ctrl then L.
5/ Layers Palette - The Basics (Background Layers And “Unlocking” Layers)
When you open a photograph onto GIMP’s workspace, the image has a single Layer, and the Layer is usually named Background. The tiny linked chain (highlighted below), indicates that the Layer is “Locked”. A Locked Layer means you cannot remove its background, or apply certain commands.
Left-click over the Background Layer to display the Linked Chain.
Add An Alpha Channel To Unlock The Layer
To “Unlock” the Background Layer, so making it editable: right-click over the Background Layer, and from the subsequent drop-down list, select Add Alpha Channel.
Alpha Channel Note
Adding an Alpha Channel enables you, for example, to erase an image’s pixels using the Eraser Tool. If the Layer has an Alpha Channel, then removing the image’s pixels will reveal the Layer’s underlying Chessboard Transparency (Alpha Channel) - as illustrated below-right.
6/ Duplicate A Layer
For most simple image retouches and corrections, you do not have to add any Layers. However, it is generally good practise to Duplicate the Layer by left-clicking and dragging it over the following Create a duplicate of the layer icon. (Or by right-clicking the Layer and selecting Duplicate Layer). (Top menu, then Layer then Duplicate Layer). You can also Duplicate an active Layer by simply left-clicking the Create a duplicate of the layer tab.
By applying changes to the Duplicated Layer, you’ll preserve the original image - on its own Layer - this is known as Non Destructive Layer Editing. If you intend to do complex work such as add elements to the image, create photo compositions, or add text and other effects - it is much better in the long run, to utilise separate Layers for those tasks.
A Layer does not need to have an Alpha Channel before Duplicating.
Additional Layer Notes
Each new Layer begins as a transparent sheet over the background. As you add Brush Strokes, Vector/Raster Objects, or Text - you cover up parts of the Background Layer.
As long as you have created an Alpha Channel, transparent parts allow you to see through to underlying Layers, and transparency is represented by the following Chessboard Effect.
You can stack Multiple Layers to create whatever effect you like - such as artistic compositions, photographic collages, or complex illustrations.
Layers Tutorial For Beginners Plus (Confident Beginners)
In the following tutorial, I demonstrate how to a create a five-layered image; I will then show how easy it is to drag the Layers thereby creating different stacking orders. Amongst other edits, I demonstrate how to alter the Layer’s Opacity and Blending Modes, and how to apply Layer Styles - for example, Drop Shadows and Strokes.
Open the Four Transparent Beer Glass Start Images onto GIMP’s workspace. And then create a New Transparent Layer, and Copy and Paste the Four Beer Glass Images onto the Transparent Layer: - as fully demonstrated at the beginning of this Understand Layers tutorial here.
After you have completed this, your workspace will be similar to mine below, and you are now ready for the next step.
8/ Create A New Transparent Layer
Now, to create a New Transparent Layer: from the bottom of Layers Palette, click the following Create a New Layer tab.
Then from the subsequent New Layer dialogue box, enter a Name for your New Layer, for example, Background Pattern. And then click OK.
A new Transparent Layer will then be added above the active Layer, as illustrated below.
Another way of creating a New Layer is from the top menu, choosing Layer and then choosing New.
9/ Reposition A Layer
To reposition the (New Transparent) Layer: left-click over it, and then drag the Layer down to, and slot it into the bottom of the Layers Stack - as illustrated below.
Now is a good time to save your Layered Image as a GIMP XCF File.
Your Layers Palette now displays the Four Beer Glass Layers, and Two Transparent Layers. If you cannot see all of your Layers, elongate the Layers Palette by left-clicking and dragging the bottom of the dialogue box downwards.
Because the New Transparent Layer, (Background Pattern) is at the foot of the Layers Stack; it means, that the New Transparent Layer, (Background Pattern) and whatever it may contain, will display below (or behind) the rest of the Layers; for example, the Beer Glasses.
11/ Fill A New Transparent Layer With A Pattern (Complete Fill Layer Tutorial Here)
First, ensure the Background Pattern (the Bottom Layer) remains active. Now, from the
left-side Toolbox, activate the Bucket Fill Tool.
Fill The New Layer With A Pattern
To fill your New Layer with a Pattern: from the Bucket Fill Tool’s left-side Options Panel, mark Pattern Fill, and then left-click over the small pattern swatch, as illustrated below-left. And from the subsequent Patterns Library; left-click to select a pattern of your choice - as illustrated below-right.
Now, (ensuring the Background Pattern Layer remains active): left-click over your Layered Image. This fills your image with the Maple Leaves Pattern. And because the Layer is at the bottom of the Layers Stack, the Pattern appears to be behind the Beer Images - as illustrated below.
12/ The Opacity Slider
Now, to display the Pattern behind (for example) the Amber Coloured Beer Glass: first,
left-click to activate the Amber Coloured Beer Glass (Clipboard #3) - as illustrated below.
And then left-click over the Layer Opacity slider, then drag it to the left - as illustrated below-left. I have reduced my Layer Opacity slider to 38%, which shows the Maple Leave Pattern through the Amber Beer Glass Image - as illustrated below-right.
Tip: Quickly Change The Opacity Using The Arrow Keys
To quickly change the Opacity setting: first, click over the Opacity slider’s numerical values, and ensure they are highlighted, as illustrated below.
Then, whilst the Opacity values remains highlighted: immediately tap your Keyboard’s Upwards-facing or Downwards-facing Arrow Key.
Return the Amber Coloured Beer Glass’s Opacity back to 100%, and ensue the Amber Coloured Beer Glass remains active.
13/ Blending Modes
Directly above the Opacity slider, you will see a tab named Mode: Normal. This is referring to your Layers’ Blending Modes. Click the tiny arrow next to Normal, as illustrated below-left, to reveal a drop-down list. The Blend Mode’s drop-down list displays your choice of Blending Modes. Normal has no effect whatsoever. Normal is therefore GIMP’s default Blending Mode.
You need more than one Layer to be able to alter (the Top Layer’s) Blending Mode.
(What Are Blending Modes? A Complete List of Blending Modes - And Their Effects, Plus A Mini Tutorial Can Be Found Here).
Blending Modes alter an image’s pixels depending on the Blending Mode and the image beneath it. For example, if you activate the Amber Coloured Glass’s Layer, and then click open the list of Blending Modes. And then change the Blending Mode from Normal to Dodge - the Amber Coloured Beer Glass would change to the following.
Experiment with different Blending Modes to see how they change your image.
Blending Modes can be excellent when applied in conjunction with Background Removal Tools and various Commands. Additionally, reducing the Layer’s Opacity further changes your Layer’s appearance.
Quickly Scroll Through And Change The Blending Modes
To scroll through, and quickly change the Blending Modes: first left-click to highlight any Blending Mode - as illustrated below.
Then, whilst the Blending Mode remains highlighted, scroll through the Blending Mode choices by tapping either the Top or Bottom Keyboard Arrow - as illustrated below.
Return the Amber Coloured Beer Glass’s Blending Mode back to Normal.
14/ Delete Layers
To Delete a Layer: right-click over the Layer, (for example, the Amber Coloured Beer Glass’s Layer). And from the subsequent drop-down list, click Delete Layer.
Alternatively, left-click - and then drag the Layer you want to delete over the following Delete Layer bin icon. (Simply left-clicking the Delete Bin will delete an Active Layer).
You can return your image to a previous state by pressing the Ctrl Key, and then tapping your Keyboard’s Z Key. (Ctrl then Z).
15/ Reposition The Beer Glass Images
To reposition an object within a Layer. First, activate the Object’s Layer - (the Amber Beer Glass’s Layer, for example). The active object will then be isolated by a Rectangular Shaped Selection - as illustrated below.
Then from the left-side Toolbox, activate the Move Tool.
Now, left-click over the Amber Beer Glass Image, and then drag it to a different position - as illustrated below.
Continue repositioning the remaining Three Beer Glasses to you liking. After you have repositioned the Beer Glasses, (and have set a Blending Mode of your choice): you are ready for the next step.
Tip: Reposition Objects In Layers
To reposition the Beer Glasses so they are either in front or behind their neighbours;
left-click and drag the appropriate Layer either up or down the Layers Stack. This is a little like shuffling a deck of cards.
Now is a good time to save your Layered Image as a GIMP XCF File.
Blending Modes Note
The following example demonstrates what happens when I change Beer Glasses’ Blending Modes. I changed the Top Layer’s Blending Mode to Screen, the Second Layer’s Blending Mode to Hard Light, the Third Layer’s Blending Mode to Addition, and the Fourth Layer’s Blending Mode to Screen. Remember, Blending Modes react to the Layer that is beneath the targeted Layer.
16/ Rename Layers
To Rename a Layer: right-click over the Layer you want to rename. And then from the subsequent drop-down list, choose Edit Layer Attributes - as illustrated below.
And from the subsequent Layer Attributes dialogue box, clear the name already there, and then type in a name of your choice, and then click OK.
Tip: Rename The Remaining Layers
If you like, go ahead and highlight, then right-click and Rename the remaining Layers (one by one).
17/ Add A Drop Or Perspective Shadow
To apply a Drop Shadow to a Beer Glass Layer: first left-click to highlight (activate) a Beer Glass’s Layer of your choice.
Now, from the top menu, choose Filters then choose Light and Shadow and then select your choice from either Drop Shadow, Perspective Shadow or Xach-Effect - as illustrated below.
And from the subsequent dialogue box, enter settings of your choice, and then click OK.
I am applying the following Xach-Effect Script.
On this occasion, make sure the Keep Selection box is Unmarked - as illustrated below.
If you like, go ahead and activate each of the Beer Object Images, (one by one), and apply a Drop or Perspective, (or a Xach Effect) to the remaining Layers.
Tip: Utilise The Scroll Vertical Bar
By now, you will notice that you have accumulated a long list of Layers. You can however, scroll through the Layers by moving the following right-side Vertical Scroll Bar either upwards or downwards - depending on your requirements.
Now is a good time to save your Layered Image as a GIMP XCF File.
18/ Lower Or Raise An Active Layer
You can quickly Raise or Lower an active Layer by left-clicking either the Raise, or the Lower this layer one step in the layers stack tab.
19/ Merge Visible - Or Flatten - Layers
Prior to Merging, or Flattening your Layers, you have the option of saving your image with its Layers intact - this is important if you wish to edit your Layers at a later date. To save your Layered document as a GIMP XCF File: from the top menu, choose File then choose Save as, as demonstrated in my on-line tutorial Here.
Only after you are completely happy with your Layered work. From the top menu, choose Image then choose Flatten Image - (or choose Merge Visible Layers). Your Layers will then be Merged (crunched) together as one Layer, and they will no longer be editable. Choosing Flatten Image crunches all Layers into one Background Layer. Flattening or Merging Visible your Layers results in smaller file sizes, subsequently saving precious PC resources.
Alternatively, right-click over the Layers Palette, (over any Layer). And then from the subsequent drop-down list, choose Flatten Image - (or select Merge Visible Layers) - as illustrated below.
Choosing Flatten Image crunches down all Layers into one Background Layer - as illustrated below.
Merge Visible Note
If your image has a Transparent Background, choosing Merge Visible will retain it. You can then save it as a Transparent Gif, or apply a Fill Layer.
20/ Layer Masks (Blend Two Images Using A Mask Layer Tutorial Here).
When you select part of an image, the area that is not selected is “Masked” or protected from editing. Consequently, when you create a Mask, you isolate and protect areas of an image as you apply colour changes, filters, or other effects to the rest of the image. You can also use Masks for complex image editing such as gradually applying colour or filter effects to an image.
To add a Mask Layer to your Layer, right-click over the Layer you would like to add a Mask to. And then from the subsequent drop-down list, click Add Layer Mask - as illustrated below.
Alternatively, from the top menu, choose Layer and then choose Mask and then choose Add Layer Mask - as illustrated below.
Once you have clicked your choice of Add Layer Mask tab - from the choices above. You will see the following Add Layer Mask dialogue box. Now, ensure White (Full Opacity) is marked: and then click Add.
After clicking Add, your Layers Palette will then display then following White Rectangular Mask Layer.
Press your Keyboard’s D Key to set the default Black and White Foreground and Background Colour Swatches.
Then from the left-side Toolbox, activate the Brush Tool. And begin painting a Mask onto your image. The golden rule to remember when masking is, Painting with Black removes pixels, and Painting with White brings pixels back.
(Blend Two Images Using A Mask Layer Tutorial Here).
Paint With Solid Black To Erase Pixels.
Swap The Foreground And Background Colours
To swap the Foreground and Background Colours, either tap your Keyboard’s X Key, or click the following Double-headed Arrow.
Paint With Solid White To Bring Back Erased Pixels
A Transparency Mask can be added to each Layer, it's called Layer Mask. A Layer Mask has the same size and same number of pixels as the Layer to which it is attached. Every pixel of the Mask can then be coupled with a pixel at the same location in the Layer. The Mask is a set of pixels in Greytone on a value scale from 0 to 255. The pixels with a value 0 are Black and give a full transparency to the coupled pixel in the Layer. The pixels with a value 255 are White and give a full opacity to the coupled pixel in the Layer.
White (full opacity): the Mask is white in the Layer Dialogue. So, all pixels of the Layer are visible in the image window since painting the Mask with white makes Layer pixels fully visible. You will paint with Black to make Layer Pixels Transparent.
Black (full transparency): the Mask is Black in the Layer Dialogue. So, the Layer is fully transparent since painting the Mask with Black Makes Layer Pixels Transparent. Painting with White will remove the Mask and make Layer Pixels Visible.
Layer's Alpha Channel: the Mask is initialised according to the content of Layer Alpha Channel. If the Layer still contains Transparency it's copied in the Mask.
Transfer Layer's Alpha Channel: Does the same thing as the previous option, except that it also resets the Layer's Alpha Channel to full opacity.
Selection: the Mask is initialised according to pixel values found in the selection.
Greyscale Copy Of Layer: the Mask is initialised according to pixel values of the Layer.
Channel: The Layer Mask is initialised with a Selection Mask you have created before, stored in the Channel dialogue.
Invert Mask: This tickbox allows you to invert: black turns to white and white turns to
When the Mask is created it appears as a Thumbnail right to the Layer Thumbnail. By clicking alternatively on the Layer and Mask Thumbnail you can enable one or other. The active item has a White Border (which is not well visible around a White Mask). That's an important point. Always keep the Layers Dialogue prominently when working with Masks, because you can't see, looking at the canvas, which of the Layer or the Mask is active.
Pressing Alt (or Ctrl+Alt and click on the Layer Mask Thumbnail) is equivalent to the Show Layer Mask command: the Layer Mask border turns to Green. If you press Ctrl the Border is Red and the result is equivalent to the Disable Layer Mask command. To return to normal view, redo last operation. These options are for greater convenience in your work.
21/ Anchor Layer
When the Active Layer is a Temporary Layer (also called Floating Selection) as illustrated by the following icon; this button anchors the Layer to the previous Active Layer.
22/ Additional Commands
At the top-right corner of the Layers Palette, you will notice the following tiny black triangle. If you click it, you will see the following drop-down list that includes commands that can further edit your Layers.
23/ Toggle Layer Visibility
There will be times when you need to temporarily hide your Layer’s Visibility if you want to see another Layer clearly, for example. To do this, click the following Layer Visibility eye icon, and the contents of that Layer will then be hidden - as illustrated below.
To return the Layer’s Visibility, click back the eye icon.
24/ Linking Layers (Chain Layers)
The Chain Icon allows you to Group Layers for operations on more than one Layer at a time (for example with the Move Tool). This is a handy tab to utilise when you want to apply an Effect, or a Filter to more than one Layer, press Ctrl and hold. Then left-click to highlight two or more Layers. Now, release your mouse button, and click the following chain link icon.
25/ The Lock Alpha Channel Tab
The Lock Transparent Pixels tab confines editing to the opaque portions of the Layer.
Clicking the Lock Transparent Pixels tab prevents modification of the Layer’s pixels using the Painting Tools. For example, if you mark this option, the transparent areas of the Layer will be kept, even if you have marked the Fill Transparent Areas option for the Bucket Fill Tool.
26/ Semi-Flatten Images (For Web)
When saving Transparent Images for the web, in order for them to blend with any background colour, it’s important to optimise them correctly. To optimise your image for its new background, from the top menu, choose Filters and then choose Web and then choose Semi-flatten, as fully demonstrated in my GIMP tutorial here.
27/ Flatten Image
When you are happy with your Layered Image: from the top menu, choose Image and then choose Flatten Image. Congratulations, your work is complete and is ready to save.
Merge Down Layers
There will be times, when for example, you are repositioning Layers, that you will want to Merge Down a Layer with its Underlying Layer. To Merge Down a Layer (with the Layer directly beneath it): right-click over it, and select Merge Down from the subsequent
drop-down list - as illustrated below.
Now you are more familiar with GIMP’s Layers, there’s nothing stopping you from expanding your creativeness and producing any type of work, from simple Layered Images to sophisticated multi-imaged artwork and designs.
Wendi E. M. Scarth. Top of Page.