`manyk WEB SHARPENING ACTION

PREAMBLE

When we want to make our digital photos suitable for online viewing there can be many factors to consider, but let me focus on two that I believe to be the most important.

1: Most digital photos need to be resampled to a much smaller pixel dimension. Whether the website we are submitting to has restrictions on size or simply because many cameras produce images far too large to view at 100% on our displays, the fact is we have to resample.

2: When resampling the image a lot of pixels are thrown away. When we resample we lose data that was in our original image and for the most part we lose a great deal of sharpness and clarity in our images. Therefore, we need to sharpen.

When it comes to resampling there are factors to consider. Some folks use the single-step approach which when used on a high frequency image [lots of details] loses a great deal of perceived detail. We might think that there is not a loss when we resample our images this way ... but therin lies the issue. WE took the image and therefore have the scene in our mind, as well as a full-scale image to remind ourselves the detail is there. For those who are looking at our web-sized image for the first time, they may be missing out on a great deal. The viewer has no reference, and as responsible photographers we need to keep that in mind.

Another approach to resampling is a multi-step process. Perhaps we will reduce our images in 5-10% steps until the desired image dimensions are met. The problem here is that not all images need this approach. We would have to carefully consider if each image we loaded into Photoshop needed this type of resampling.

Yes, there are other algorithms we could use to resample our image, but I'm focusing on Photoshop here and we are primarily 'stuck' with what Adobe has provided us with.

With regard to sharpening. There are many ways to go about this but it has become somewhat of a myth that we must always save this step until the very end. The reason, I believe, is because most people really hate taking the time and effort to selectively or creatively sharpen their images. They use a single-step sharpen in Photoshop and leave it at that. Now, let's say we have an amateur [not in a bad way] that loads their 6MP image into Photoshop for the first time. They look at the image and notice how inherently soft it is compared to their 2MP in-camera sharpened images. They might apply sharpening to this full-sized image and then resample for web. But, once resampled, the image becomes soft and they apply another round of sharpening to the image. Now they have halos around edges and mottled areas in what are supposed to be smooth patches of colour. This is not something they want and this is one of the critical reasons why the myth of last-step sharpening has come to fruition.

One of the main reasons we upload our images to the internet is to show others ... so why not give them the best image we possibly can?

What I have done here is come up with a Photoshop action that takes a great deal of the 'guess work' out of this entire procedure. I have put a great deal of effort into this, testing it on as many types of imagery as were avaliable to me. It has been tested on architecturals, macros, portraits, product shots and landscapes. It has been tested on images ranging from 4MP to 12MP. Basically, it should work for any type of image from any camera that needs to be resampled for web display.

CONSIDERATIONS

There are a few things I feel obligated to mention before we get started.

1: You must have a digital image that is as sharp as you could get it with your capturing device. If your image is out of focus or blurred from the start, I am afraid this 'technique' will not help you.

2: Because I am only familiar with Adobe Photoshop, this technique is geared towards that application. I am not familiar with Elements, Paintshop Pro, PhotoPaint, Gimp etc. so if you need to know how to get similar results with those applications, please try to ask someone who knows them.

3: If working from RAW, make sure you do not oversharpen in your converter. In fact, it is best to either not sharpen at all, or sharpen very little. If working from JPG/TIFF, make sure you are using the highest quality settings in your camera, and make sure that sharpening is not set too high in your camera settings.

Reasoning - Cameras and RAW converters do an ok job for single-step sharpening. But single-step sharpening is very limited, and often introduces artifacts as well as sharpening noise.

4: I have tried to make this as simple as possible. In fact it can be as simple as a single click in Photoshop. But for those who are very familiar with Photoshop, this can be enhanced or modified quite easily, and for each image you process you could tweak the settings if you were so inclined.

PROCEDURE

1: Download my action [Manyk_SRS_PSAction.zip], unzip it, and load the .atn action file into Photoshop's action palette.

2: Load your full resolution image into Photoshop and do all of your editing, cloning, toning, color correction, cropping or whatever you want to the image to get it the way you want it. Do not sharpen or resize your image, as that is what my action does for you.

3: Use my action to sharpen, resize and sharpen your image for web display.

4: Tweak the "Final Sharpen" layer ... if need be.

5: Flatten the image

6: Save the image using "Save As" ... do not overwrite your originals!

WHAT IT DOES

Here's an image with the complete action. The steps which are numbered with the blue circles in the image, are outlined below:

1: Takes a snapshot of the full document and names the new snapshot "Before Manyk SRS" [History Palette]
2: Converts the image to 8Bit color mode [We don't need 16 or 32Bit for web display]
3: Flattens the image to one "Background" layer
4: Duplicates the "Background" layer
5: Renames the duplicated Background layer to "Presharpen"
6: Adjusts the Blending options of the "Presharpen" layer
7: Applies a slight USM to the "Presharpen" layer
8: Merges the layers.
9: Resamples the image to fit within a 600x600 pixel dimension [Maintaining aspect ratio of course]
10: Duplicates the Background layer
11: Renames duplicated Background layer to "Final Sharpen"
12: Adjusts the Blending options of the "Final Sharpen" layer
13: Applies USM to the "Final Sharpen" layer.
14: Applies USM to the "Final Sharpen" layer.
15: Applies USM to the "Final Sharpen" layer.

Now, I bet you are looking at the last three steps and wondering why the heck does this thing have three rounds of USM? Is this an error in recording the action perhaps? Well, it was not an error, it was most definately intentional. Read the next section.

ACTION DETAILS

I will now clarify, for those who need/want it, some of the steps the action performs.

1: This is a 'just in case' measure. It's always nice to be able to go back to the start.



2: Many photographers edit their images in 16Bit mode. And with Photoshop CS2 we also have the ability to edit in 32Bit mode for such things as HDRI imaging. These modes increase file sizes and generally are not at all needed for web display. Converting to 8Bit also speeds up the rest of the action.

6: Blending options for layers are powerful things. In the next step the action will apply an unsharp mask to this layer, but, we want to be able to control the appearance of the USM with much more control than USM on a flattened layer alone. The settings are shown in the image below.



With these blending options the USM mask in the next step will NOT sharpen extreme dark and light areas of our image. This will greatly reduce blocking up shadows and blowing out highlights in our resampled image.

NOTE: This is a dialog step in the action. So for those who wish to tweak, it is easily enabled. If you are a "novice" to Photoshop, you needn't worry about this dialog because by default it will not show up. I have tested these particular blending settings on a wide range of imagery and believe them to be the best "value for your dollar", so they should be fine if left alone.

7: The USM settings for the Presharpen layer are set at:
Amount-175%
Radius-1.0 pixels
Threshold- 5 levels

This is another dialog step which can be enabled in the action. And again these settings are a best "value for your dollar". Basically what these settings do is they sharpen the entire image enough to allow detail to be retained in the image once it has been resampled. The threshold is set at 5 to reduce the risk of sharpening any noise that may be present in solid tonal areas such as sky. Now, if you were to enable this dialog and see the preview of the USM on your full-sized image you will see that this 'appears' to be far too much sharpening. But keep in mind that with the previous step's blending options, as well as the fact that this image will be resampled, these settings need to take in to account the subsequent scaling.

9: This step resamples your image to fit within a 600 pixel long dimension. So if you have an initial 2:3 aspect ratio image it will resample that image to 400x600 pixels. I have set the action up to use the "Fit Image" automation because it makes it much easier for those who are resampling both landscape and portrait aspect images. To change the dimension to your preference for web display, simply double click on the "Fit Image" command in the action's list of commands and it will bring up the dialog for you to edit that particular command. For example, if you want your images to have a long dimension of 640 pixels, simply change the '600' in BOTH the Height and Width boxes to 640, then click "ok".



NOTE: Make sure that in your Photoshop preferences you have Image Interpolation set to Bicubic. The "Fit Image" automation resamples your image based on this setting and Bicubic is the least destructive when resampling your images, either on it's own or when used with my action.



DIFFERENT SIZES FOR DIFFERENT PURPOSES: Let's say you want each image you process to be for a different website's requirements. Well, all you have to do is enable the dialog for the "Fit Image" command by clicking on the square just to the left of that command.



What this will do is, each time the action is run it will pop up the "Fit Image" dialog so that you can input different dimensions each time. Once you click "Ok", the action will continue to the end.

12: Another Blending option. This time the options allow for more of the image to be sharpened. But extreme dark values as well as highlights will be untouched to reduce the risk of sharpening halos. The settings are shown in the image below.



NOTE: See NOTE for step 6.

13-15: Three steps of USM at low radius values are MUCH better for a final web image than any single step process. This can really make fine details pop out at you, especially when all the previous steps were taken into consideration! The settings for each step are as follows:
13:Amount-110% - Radius-0.3 pixels - Threshold- 0 levels
14:Amount-100% - Radius-0.2 pixels - Threshold- 0 levels
15:Amount-100% - Radius-0.2 pixels - Threshold- 0 levels

Now, these last three settings are as great as I could make them for MY imagery. They should be fine for most types of images, but this is why I have left the final stages somewhat editable. If you find that there is a bit too much sharpening you can simply go back a step or two in the history palette. OR, as you will notice, the action does not flatten the image and you are left with a "Background" layer and a "Final Sharpen" layer above that. The "Final Sharpen" layer is set with the blending mode at luminosity with a 60% opacity. You can adjust the final sharpening result by adjusting the opacity of the layer. If you want the image to be slightly sharper looking simply slide the opacity towards 100%. If you want it to look softer, slide the opacity slider towards 0%.



NOTE: Again I will state that for those familiar with Photoshop, the last three USM steps are dialogs that can be enabled within the action.

FINAL WORDS

The action is quite simple yet incredibly robust for those who want to add steps to it. Feel free to make it as useful to YOU as possible. Nothing here is new folks, it's all been done before. I've just put it together in a way I know has made things much easier for me with much better results ... and I thought I'd share it with you.

`manyk