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Photoshop Calculations = Math, right?

This is a goes post from the talented Janine Smith In my opinion the name "Calculations", in and of itself, is the biggest drawback of this really awesome tool. I think if the folks at Adobe had called the thing "Melvin" there wouldn't have been nearly the confusion over it. The name is daunting to those of us with Math Phobia, but the command itself is just nifty!

Even when I began to understand that Calculations might actually be a feature I could use in my work, I just wasn't getting it! I watched training videos, read articles, asked people to just wasn't getting through. For some reason, even the explanations were coming across as somewhat mathematical therefore they were bypassing the connection in my brain that would allow them access into the inner sanctum of my cerebral cortex. Until the day
Deke McClelland was guest-blogging on Scott Kelby's blog and the clouds parted and the sun shone through!

I'll say right off the bat that Deke's tutorial was dealing with Calculations as a masking tool. I think as a tool in photo restoration, that alone can be invaluable. But then I also started looking at the other use for Calculations for me, as a restoration artist. Just what is that, exactly?

Well, literally, it is what it is! Calculations is a Channel Blender! I see three main areas, so far, in which Calculations can benefit photo restoration. Analysis, channel blending and masking. Remember, since Calculations only work in RGB mode, always scan your photos, yes, even the black and white ones, in color! Calculations aside, it should be a part of your restoration workflow, lest you severely limit your repair options!

In case you've never seen Calculations, have absolutely no idea what in the world I'm talking about, you'll find this little gem in the Image menu. Image > Calculations...and this dialog box will appear.


You'll have the ability to blend different sources, different layers (I confess, up to now I've only experimented with "Merged" layers), and any two of the Red, Blue and Green channels. You'll have the ability to invert one or both of the channels .You'll also have at your disposal all of the familiar blending modes as well as two new ones: Add and Subtract. Then you can decide whether to make your blend into a new document, selection, or a new channel.

Regarding analysis, Calculations is a great way to take a photo, for instance, that's so faded it's not immediately clear what is even in the picture, and determining it's chances of restoration. In the example, below, from my families personal collection, I could see a couple people and had a good idea one was my grandfather, but wasn't really clear about the entire composition. After filtering it through Calculations using the green and the blue filters (the red was almost totally shot), I can see it's my grandfather standing next to my grandmother, with her holding up her hand to show off her wedding ring. Since she'd probably only being doing that at the time of her wedding, not only do I now know for certain it's my grandparents in the photo, but I also know the photo was taken in 1921. My mother was also thrilled to see her father was smoking his pipe in the photo, which is how she remembers him best!


By using calculations as an analysis tool, I determined in less than five minutes that, yes, this photo could be restored, given time and a lot of patience, and that it would very much be worth it to my family.
Over the next couple of weeks, I'm going to go over the two other photo restoration worthy benefits of Calculations, channel blender and masking tool.

Janine Smith is the owner of Landailyn Research and Restoration, a Fort Worth, Texas based company whose services include family history research and photo restoration. Janine honed her skills in restoring badly damaged photos as a volunteer with Operation Photo Rescue, a non-profit organization whose mission is to repair photographs damaged by unforeseen circumstances such as house fires and natural disasters. Janine’s work is well-known in the world of genealogical and historical societies, museums, libraries, university archives, and non-profit organizations; appearing on the board of directors for several organizations and institutions. She is a sought-after lecturer on photo restoration and preservation to libraries, genealogical and historical societies.


Lightening A Dark Photo


This is a guest post by the talented Janine Smith who is one of the best photo restorationists I know.

As a photo restorationist I'm given many types of photographs in all manner of conditions. Sometimes the image can be very dark and given to me as a 'lost cause'. This isn't always the case, here’s just one way to lighten them up.


Repairing An Aperture Library

This is a guest post from Scott Engel

I want to thank Richard for giving me the opportunity to be a guest blogger. I am a freelance photographer specializing in wildlife, but I do a lot of zoo photography as well. In a past life I also worked for Apple Retail as a Creative/Trainer and I hold an Aperture 3 Certification.

Aperture is a wonderful application. Sometimes, however, you might encounter an error with your library and it will not open. Aperture has a great set of troubleshooting tools in case your library becomes corrupt or fails to load.

1. While holding down the Option and Command keys, click on Aperture to launch it.

2. There are three tools to help you repair a library:
  • The first choice, Repair Permissions, will address a majority of issues and is the fastest.
  • The second Choice is to Repair Database. It takes a little bit longer but it’s more thorough.
  • If your library needs some extra attention, then choose Rebuild Database. This is the most time consuming, but is very thorough.

3. Click Repair to make the fix.

You can contact Scott on Facebook at | Twitter @Engelimages
He also has a small photo gallery at

The Eight Step Grunge Look

This is a guest post by the talented Glyn Dewis (who is letting me take more of a family vacation).

The images above show the 'out of camera' and 'final edit' versions of a photograph that I took of a 'Rough Sleeper' when out on a photo walk in the coastal town of Brighton, UK, and in this post I want to show you each of the stages I went through in Photoshop to achieve the final look.

Panorama and Content Aware Fill for Photoshop CS5 and Photoshop Elements 9

First of all, can I say what a privilege it is to be appearing on the Richard Harrington Blog. Rich has been a major contributor to for some time and I've been a huge fan for much longer than that!

When Photoshop CS5 was released one of the stand out new features was Content Aware Fill. This function could be used to remove unwanted objects or, as we see here, fill empty space around a panorama with new content.

Photoshop Elements 9 came shortly after and boasted the Content Aware Spot Healing brush but not Content Aware Fill, so there’s no way of filling in those blank spaces in panoramas right? Wrong...


Luminosity Sharpening 3 Ways

Guest post By Michael Hoffman

The Luminosity Blend Mode allows us to use the brightness values from one layer to make adjustments to the brightness of underlying layers, without creating unwanted shifts in the hue of the underlying layers.
This can come in useful with our sharpening workflow.the image below is an example of an image that was sharpened heavily, and the resulting halo along the edge boundary. This has developed some weird color shifts as a result of the sharpening:

Let’s take a look at three ways to use the principles with Luminosity Mode blending to eliminate the color shifting, and leave the hue intact as we add brightness and darkness along the edges to sharpen our images. You may have seen recommendations that you convert your image from RGB to Lab and sharpen the L channel, then convert back to RGB. This technique will achieve essentially the same result, without the conversion – and without having to flatten a multi-layer image.

Sizing Images in Photoshop

Guest blog post by A.J. Wood

Thanks to Rich for having me here as a guest blogger. I’m not one to mince words, so let’s jump right into the tutorial. We’re going to discuss Image Sizing. Often overlooked, sometimes confusing, easily dismissed, but oh so important. First thing is to get to the Image Size command: Press CMD+OPT+I (CTRL+ALT+I) to open the Image Size dialogue or choose Image->Image Size from the Photoshop menu.

Pixel Dimension for Screen / Document Size for Print

Notice the two distinct areas for sizing an image – Pixel Dimensions and Document Size. Pixel Dimensions are used to size an image for a display, e.g., monitor, overhead projector, television. Document Size is necessary when outputting an image for print.

Resampling Changes All Field Values (Resolution x Size = Pixel Dimensions)

When “Resample Image” is checked, changing values in any field effects the entire dialogue. If you look closely you can see that the resolution of the image (300) multiplied by the height in inches (5) gives us a requirement of 1500 pixels to print. (300×5=1500). Resampling changes the pixel dimensions and total pixel count.
Whenever I size an image, I always set the resolution field first. Once that’s set, then I move to the appropriate width & height field for outputting my image.

No Resampling Means Image Integrity is Maintained

When “Resample Image” is unchecked notice how the Pixel Dimensions become locked. Adjusting resolution will simply increase or decrease the size of an individual pixel. The integrity of the image does not change because the pixel count stays the same.
Notice how the image went from being a 5×7 print to less than two inches in size. (300×1.667=500).
In the above figure any attempt to get a 5×7 print results in lower resolution. Because “Resample Image” is unchecked, there are only 500 pixels for width & 357 pixels for height.

It’s the Total Number of Pixels, not Resolution You Should Watch

I often hear folks argue about resolution in terms of printing, but what’s most important is the total number of pixels when the image is first opened. An image from a digital camera measuring 3500×2400 pixels gives you a lot more options for output then one taken off the Internet at 400×250. It will always be easier to take a large image, and reduce the size, then to take a small image an size it up. Resampling is not bad, but you are either deleting existing pixels (downsampling) or creating new pixels (upsampling). Some resolution values to keep in mind:
Screen resolution – 72-96ppi – PowerPoints, websites, emails, TV Office printing – 150ppi – laser or inkjet printing, drafts, proofing Professional printing – 240-300ppi – can be higher, but these values tend to work just fine
Keep in mind, resolution can be set TOO HIGH. If your desktop printer is rated at 240ppi you receive no benefit from outputting an image at 600ppi. In fact, you offload the resampling onto the printer which will result in a pixelated image.

 Quick Crop Tool Tip

As a final tip, if you really dislike the Image Size dialogue, you can skip it and use the Crop Tool instead. Simply specify the width, height AND resolution, and your image will be resampled appropriately. (Keep in mind, all the rules still apply, the Crop Tool just executes commands quicker)
I hope you found this information useful. You can follow me on Twitter
@aj_wood where I post daily Adobe tips Monday through Friday at 12PM CST or feel free to visit my blog