EZ Green Screen 4 - Software User Guide

Introduction

We highly recommend that you read through this entire user guide. There is a lot of really useful information in this document. We receive hundreds of questions each month about how to use this software. Almost all of the questions can be answered in this user guide (and answered better in most cases with pictures and illustrations). However, if you don't see an answer to your question in this document then feel free to email us your question.

First, there are a lot of available adjustments in EGS. However, don't be overwhelmed because adjustments are often not even needed. They are there if needed though.

EZ Green Screen simplifies chroma key extractions. Version 4 of the software now has a very advanced adaptive algorithm. What this does is analyze everything about your image and adjust how it extracts accordingly. Most of the time, you will get good results without needing to make any adjustments.

The software will auto detect your screen color. It works with both green and blue screens. Not only does it auto detect green or blue, the software analyzes the lighting conditions and shade of green or blue to extract. You can work with many green or blue backgrounds that are not even a true chroma key green or blue. For example, you can extract images that have a blue sky for a background.

Since the software is doing so much work behind the scenes, it normally takes about 10-15 seconds for it to extract an image. Yes, we could have written a simple program to do a simple color selection and knockout in about 1 second. However, this would never give consistent and reliable results for a wide range of image conditions. Embrace the fact the EZ Green Screen software spends a few extra seconds working on your images to save you a LOT of work.

Finally, don't forgot your are working in Photoshop. This is a good reason to use a plugin that works like EZ Green Screen does. EGS gives you all of the Photoshop layers that it builds. You have complete control over any touch-ups after the extraction. EGS does non-destructive extractions. What this means is that the original image has not been processed in ANY way. It remains untouched in it's own layer. All adjustments are mode in the mask and the blending layers.


Getting Started

Single Mask or Dual Mask?

Before running EZ Green Screen, you will need to decide whether you want to do a single mask or a dual mask extraction. To use dual mask, just make a quick selection around the hair area.

So what is the difference?

Single mask applies the same settings to the entire image. Dual Mask applies different settings to pre-selected area (typically the hair) than it does for the rest of the image. Also, when in dual mask mode, the Halo Chop and Foreground Recovery are applied OUTSIDE of the selection only. This protects the hair area from these adjustments because they are designed to make harder edges.

Running EZ Green Screen

New to version 4 - EZ Green Screen now has 2 menu items under the Photoshop Filter menu.

The menu item "EZ Green Screen 4" is the standard mode. It will run EZ Green Screen and open up the user interface where the user can make adjusts to the extraction or add a background.

The menu item called "EGS Pro 4 - One Click" will skip the user interface. With the software's new adaptive algorithm, it auto adjusts itself for each image. In many cases, you don't need to adjust anything so this is a handy feature.

The One Click option works with dual mask too. If you make a pre-lassoed selection, it will automatically fine tune each of the 2 regions.

Note: When recording EZ Green Screen in actions, the action will bypass the user interface regardless of which menu item you ran. However, if you use the standard menu item then the action will record the extraction settings that you use and apply those to each image. Also, if recorded using the standard menu item, you check the "show dialog" check box next to the EZ Green Screen step in the action if want the action to bring up the user interface when ran. With the EZ Click menu item, there is no way for the action to show the EGS user interface.

User Interface Overview

1. Manage Presets Button - Save or delete extraction presets

2. Presets Drop-down - This applies a saved extraction preset

3. Shows The chroma key color extracted

4. Reset Button - This applies the default extraction settings

5. Opens the mask adjustment window

6. Opens the spill adjustment window

7. Opens the light wrap adjustments

8. Add a background - You can also position your FG here

9. Changes the background solid color

10. Selects your preview mode

11. Zoom / Pan - Allows you to zoom and pan - CS5 and higher

12. Fit Screen - Fits the image to the screen size

13. Refreshes preview - if Photoshop isn't displaying it correctly

14. Views license - If running Free mode it will be "Activate"

15. Exit - Closes EZ Green Screen and doesn't apply extraction

16. Apply - This applies the extraction and closes EGS

17. User Preferences - Sets you custom options

18. Help Topics - Has some basic instructions for EGS


Mask Adjustments

Important Concept (Make sure to read this): When running Dual Mask Mode, the Dark Hair Recovery, Light Hair Recover, and Smart Radius adjustments are made to the HAIR REGION ONLY. Halo Chop and Foreground Recovery are made to the NON-HAIR REGION ONLY. The Mask Feather adjustment is made to the entire image.

When running single Mask Mode, all adjustments are made to the entire image, with the exception of the Smart Radius adjustment. The Photoshop Smart Radius feature tends to erase skin or clothing areas with green or blue spill. Therefore, it is disabled in Single Mask Mode.

Where the adjustments are applied when using Dual Mask mode

Dark and Light Hair Recovery Sliders

Important Concept - These adjustments use the new version 4 adaptive algorithm. Most of the time you don't need to adjust them (and usually should NOT adjust them). The default values are 50 and represent what the software determines the "best" adjustments for each channel was when creating the mask. Any adjustments made away from 50 is relative to what the software's adaptive algorithm sees the best points for adjustment.

Note: For single mask the default for the dark hair recovery is only 40 (to compensate for any shadows on the screen).

This is a HUGE difference from how version 3 works. In version 3, the mask channel levels were set to fixed values. It was up to the user to find the best adjustment point. BY FAR, the biggest feedback that we received is that the levels adjustments were too confusing and almost nobody used the adjustments. If there was any screen left in the mask then many people were left wondering what to do.

Based on the feedback, we decided to make this easier for the users so we created the new algorithm which can analyze all the channel histograms and "think" on it's own. With version 4, if your mask looks OK, then you can just ignore the hair adjustment sliders. Here is an example of how the adaptive algorithm adjusts the slider for two different images that have very different screen conditions. These levels adjustments (hidden from the user) are for the Dark Hair Recovery with the default slider value of 50. Again, if your mask looks good, then don't adjust the hair recovery sliders.

Smart Radius

Smart radius in ONLY available when running Dual Mask. This is because smart radius tends to erase areas on skin and clothing that have color spill. This uses Photoshop's Refine Edge / Smart Radius feature that is for CS5 and higher. Therefore, the feature is disable for CS3 and CS4. The smart radius calculations are blended into EZ Green Screen native mask. Sometimes this will produce really great masks. Other times, the masks may be better by turning it off. As a general rule, smart radius usually work really well for dark hair. For blonde hair, you will often see very little change, and sometimes the mask looks better with it turned off.

The default settings in EZ Green Screen are to use Smart Radius at a lower radius which is determined by the actual image size. The default size is proportional to the original image size. You can also adjust the smart radius from 1-250 pixels that is uses for the calculations. Additionally, there are 2 blending modes to apply it (default is set to Blend).

Blend Mode (default): This blends the native EZ Green Screen mask with the Photoshop Smart Radius mask. It keeps the foreground detail from both masks by utilizing "lighten" blending which keeps the whitest values from each mask. This helps to prevent Smart Radius from partially erasing areas in the hair which should be 100% FG (which smart radius tends to do at times).

Replace Mode: This replaces the entire hair region with the Photoshop Smart Radius mask.

Halo Chop

This feature does just what is says..........chops off the annoying edge halos that are common with chroma key photography. The edge halos are typically caused by the chroma key screen luminance. A really bright screen can cause light haloing while a really dark screen can cause dark haloing. The problem becomes exaggerated when the image has some edge blurring because the luminance from the screen will mix with the edge of the foreground. While spill correction can remove the green or blue hue on the edge, spill correction won't remove luminance issues. That is where Halo Chop comes in.

Halo Chop contracts (sometimes referred to as "chokes") the mask by either 1 or 2 pixels. When running Dual Mask, Halo Chop only applies itself to area OUTSIDE of the selected hair region. This is because it will "chop" away hair detail. For hair, the haloing tends to be more of a "glowing" and can be fixed better with a shadow or light wrap which will allow the mask to keep the hair detail.

By default, haloing is turned ON with Dual Mask mode (if the image is large enough) and OFF in single Mask Mode. The default radius when in Dual Mask mode is determined by the image size.

Low Light Green Screen

Without Halo Chop

With Halo Chop

Foreground Recovery

When you have clothing that is "greenish", such as a teal or the common "Spartan" green in sports uniform, these can usually be recovered in the EGS version 4. Use the Foreground Recovery slider to recover these areas. When running Dual Mask, Halo Chop only applies itself to area OUTSIDE of the selected hair region. This adjustment can make the edges harder so it's best used in combination with Dual Mask. Just make sure that you don't select any of the clothing that you want to recovery in the hair selection. If using a stronger FG Recovery (over 40%), it's best to use a little mask feathering to keep the edge a bit soft so it blends nice into the new background. The default Mask Feathering value typically works fine.

You will typically need to use Foreground recovery together with the spill suppression settings to recover greens. Also, pure chroma key green or blue requires manual recovery. See our advanced tutorial for this.

Original - "Teal" Shirt

Without FG Recovery

With FG Recovery

Mask Feather

The Mask Feather feature blurs the entire mask from 0-1 pixel. This softens it a little so it blends better into the new background. If you want to blur it more than 1 pixel then you can do that in Photoshop after running EZ Green Screen. EGS outputs the mask so you can do whatever you want with it after running EGS. Well, that cover this one. It's good to have an easy topic 🙂


Spill Correction

Spill Correction Window Overview

1. Correct Color Spill Section - The adjustments in this section are the main spill correction adjustments.

2. Spill Correction Opacity - This sets how much spill correction opacity is used.

3. Spill Color Range: Warms - This sets where spill correction is applied. It determines the range of colors in the warm spectrum that are affected by the spill correction. See more details below.

4. Spill Color Range: Cools - This is the same adjustment as Spill Color Range Warms except it applies to the cool tone colors,

5. Edge Color Blending Section: These settings are optional to use and are meant to further aid in spill correction, especially around the hair. This is applied similar to how the Light Wrap is applied. The edge of the foreground is "stroked" with a color that is blended using soft light blending.

6. Mask to hair region (Dual Mask Only): This will apply the edge color blending to the hair region only. Since edge color blending is typically used to aid with spill correction in the hair, the default is for this to be turned on.

7. Edge Color Opacity: This is how much edge color that is blended. This is set to zero be default. Therefore, the Edge Color blending is normally off unless you change it.

8. Edge Color Hue: This sets the hue of the blending color.

9. Edge Color Width: This sets how far in from the edge that the edge color blending is applied.

Spill Correction Opacity

This sets the opacity of the spill correction layer. When EZ Green Screen runs, the software auto calculates the spill correction opacity. It usually does a pretty good job. Sometimes you may want to change the value a little to fine tune it.

By default, when EZ Green Screen is recorded into an action, the software will auto calculate the spill correction opacity for any image that is extracted from the action. If you want your action to use the exact spill correction opacity that was set when the action was recorded, then change this setting in the user preferences. It is only advisable to do this if you are running the action on images that were all shot under the exact same conditions.

When saving a preset, you will be given the choice whether you want to use auto spill correction opacity or to use the exact spill correction opacity setting. if the preset is going to be used for images with different screen or lighting conditions then you should select the auto spill correction opacity option.

When setting the spill correction opacity, it is pretty easy to see if it is too high or too low. If it is too low then there will still be some green color left. If it is set too high then it over-corrects the color and it leaves a pinkish color in the hair.

Spill Opacity Good

Spill Opacity Too Low

Spill Opacity Too High

Spill Color Range

This sets WHERE the spill correction is applied. Basically, it determines the range of color that the spill correction is targeted for. Although the software's algorithm is much more complex than this diagram, this is a decent illustration to help understand the concept of how it works. This diagram is for a green screen. Blue screen works the same but shifted to the blue tones.

The range of spill colors is centered around chroma key green. The spill color range warms is the hues left of this. When green spill gets on warm tones such as skin or hair it can turn it anywhere from yellow to green. When green spill occurs on blue tones it can turn these green to cyan. The software needs to shift these colors back to their original value. The spill color range tells the software how far away from chroma key green to target spill correction.

Spill Color Range Diagram

Here are examples of where the spill color range is set too high. When the warms slider is set too high then the hair color is shifted. When the cools slider is set to high then the blues jeans color is shifted.

Spill Color Range Good

Spill Range Warms Too High

Spill Range Cools Too High

The example below shows where a gold uniform gets affected by spill. When you see this happen, try turning the Spill Color Range Warms value down to 50. A value of 50 usually corrects spill removal on gold/yellow and doesn't have too much of an effect on spill removal on skin and hair. If you go too far below 50 then you start losing spill removal on skin and hair.

Original Image

Color Range Warms - 75

Color Range Warms Fix - 50

When turning down the color range settings, watch closely for spill to start coming back. The optimal spill color range warms for skin and hair is around 75. You can usually go down to 50 or a little lower without seeing too much difference. If you go too low then you can start seeing spill come back. The images below are a zoom in on the hair from the image above. On the bottom right image, the color range warms was turned all the way down. You can see a yellowish- green spill. When green mixes into hair it often become a yellowish green which is why those colors are targeted for spill correction.

Color Range Warms - 75

Color Range Warms - 50

Color Range Warms - 1

Edge Color Blending

This forces color blending into the foreground edges. The opacity default is set to zero. This feature is normally OFF. Edge Color blending is particularly useful for refining spill correction in the hair. For , the software needs to shift the foreground it back to it's original color. When spill spill results in a mix of the chroma key color and the foreground, the software can usually get the color pretty close. However, when spill turns a foreground pure green, which is often the case in the hair, the software has to "guess" at what the original color of the hair was. It always gets the green out. However, it can leave the color saturation a little low because it needs to "guess" at this when the hair is pure green and it has no information to calculate what the original color was.

Often, the hair will appear perfect in most background but could look a little desaturation in a warm tone background. This is mostly evident with blonde hair. In this example shown below, the spill correction looks good against a blue backdrop. However, against a red backdrops the hair edges appear a little desaturated from the spill correction. Add the edge color blending quickly fixes the hair.

Edge Color Blend OFF

Color Blend NOT needed

Edge Color Blend OFF

Edges Look Slightly Desaturated

Edge Color Blend ON

Looks Perfect With Color Blend


Shadow and Light Wrap

Light Wrap Window Overview

1. Mask to hair region (Dual Mask Only): If this is selected then the light / shadow wrap will only be applies to the hair region. This is helpful if you are trying to fix hair "glowing" and don't want the light / shadow wrap on the rest of the image. However, if you are trying to apply the effect for composition reasons, then you may not not want this turned on.

2. Light Wrap Mode:This is where you select between a Light or Shadow wrap.

3. Light Wrap Opacity: This is how strong the effect is applied.

4. Light Wrap Width: This is how far in from the edges the light / shadows wrap extends.

Shadow and light wrap is helpful for two main purposes. First it can help the FG blend more naturally into the new background. Edge shadowing can help give depth to the image and be really helpful to reduce the "flat" appearance that green screen compositions can have.

In addition, the shadow wrap can be really helpful to reduce "glowing" that can sometimes be in the hair in the extracted image when it is put into a darker background. This glowing appearance is caused by the chroma key screen luminance. The worst case for this is typically a bright green screen, a person has dark hair, combined into a dark background. The bright green screen with illuminate the hair. Then when the person is put into the dark background, the hair appears to glow. Spill correction can remove the green tint but it can't fix the illumination.

There are only 2 ways to solve the glowing hair. You can either mask out the hair or make it darker. Making it darker is the best choice if you want to retain detail. This is where a shadow wrap can really help out.

Hair illumination is caused by the new background having different luminance than the original chroma key screen. But the screen was removed, right? So why does it matter how bright the original screen was? Here is the deal with fine strands of hair....... you are dealing with sub-pixel resolution. The actual width of a strand of hair is less the the width of one pixel. That means that those pixels are always a blend of the green screen background and the hair. To save the hair detail, the software need to partially erase these pixels and then remove the green hue. However, the luminosity is still a blend of the original green screen and the hair. The ONLY way to fix this WITHOUT erasing the hair is to then alter the luminosity of the extracted hair. This example shows the worst case where you have dark hair, a bright green screen, and then place into a dark back ground. As you can see, in the 50% gray background, the hair looks PERFECT and a shadow wrap is NOT needed. When the new background brightness is dropped to 20%, then you can start to see the illumination from the original green screen image.

No Shadow Wrap

Background Brightness = 50%

No Shadow Wrap

Background Brightness = 20%

With Shadow Wrap

Background Brightness = 20%

The zoom in shown below illustrates the sub-pixel resolution with strands of hair combined with slight edge defocus that is normal for any photo. As you can see, the strands of hair are green. In fact, the hue is almost identical to the green screen itself. The pixels are actually getting more information from the screen than from the hair itself, The hair is only darkening the pixels a little bit. This is why these types of extraction can never be made well with a hard selection tool (magic wand for example). It also why green spill removal will always be needed when you keep fine strands of hair. This also illustrates why the hair takes on the illumination from the green screen. To have a really great, detailed hair extraction, the software can only make this edge selection with luminosity and NOT color (that is what the hair recovery adjustments do). Also, the spill needs removed, and a shadow or light wrap may be needed depending on original screen color, hair color, and new background color.


Adding Backdrops

In version 4, you can now add backdrops from the EZ Green Screen user interface. Of course, this is optional as you can always add backdrops right from Photoshop. However, it's ofter helpful to use the EZ Green Screen's software adjustments while viewing the foreground against the actual background that you intent to use for the final composition.

Backdrops Window Overview

Note: You must add a backdrop before the resizing and movement option are available to use.

1. Add Backdrop Button: This allows you to add any background of your choice. If you add a backdrop more than once, it will replace the current backdrop with the new backdrop. The background image is converted into a smart object and scaled to fit the foreground image.

2. Scale BG: This scales to background image in relationship to the foreground image size from 50-150%. Note that the 50-150% is in relationship to the FG size (the size that the BG was when first added). When scaling a BG, the FG appears to be a different size in relationship to the BG. However, the FG is NEVER resized. All resizing is done with the BG. Also, since the BG is contained in a smart object, all resizing is done non-destructively.

3. Move FG Left / Right: This moves the foreground image left and right in relationship to the background image. Zero value is referenced to the center of the BG.

4. Move FG Down / Up:This moves the foreground image left and right in relationship to the background image. Zero value is referenced to the BOTTOM of the BG.

The background is always converted into a smart object and then resized to fit the foreground. Even if the foreground looks to change size compared to the background, the scaling always occurs ONLY on the background. This is to preserve the FG and all of it's associate layers.

The default placement of the FG into the background is bottom-center. The foreground movements are referenced to this point. Also, when the background is scaled, the movements are scaled according to the according to the BG size.

Original Image

Background

Default Image Placement

Default placement - FG with portrait aspect ratio, BG with landscape aspect ratio


Photoshop Adjustments

Remember, you are still inside of Photoshop! While EZ Green Screen generally does some pretty awesome extractions, we still give yo all of the layers just in case you need them. In fact, EZ Green Screen is completely non-destructive to the foreground layer. Nothing is changed, no data is lost. Everything is done in masks and blending layers. You have complete control over all of these after extraction should you ever need them.

EZ Green Screen Photoshop Layers

1. Extracted Image Group: Contains all of the foreground layers

2. Manual Spill Correction: This is an Empty Layer, set to color blending at 50% opacity for manual spill correction.

3. Edge Color Blend: Contains the Edge Color Blending.

4. Spill Correction: The layer contains the spill correction blend colors. The Mask is created with the Spill Color Range in EGS to determine where the correction gets applied.

5. Light Wrap: Contains the light or shadow wrap

6. Foreground: The layer is the original, untouched chroma key image. The mask contains the transparency.

7. Add Backdrop: Contain the backdrop that you added or will be empty if no backdrop was added

4. Color BG: A solid color layer with the color selected in EGS