Artifacting for Istockphoto I

Original Post

How to Remove Artifacts and Avoid Istock Rejection (Part 1)

Are you ready for this? I couldn’t use the actual words in the title because I was afraid I’d scare off those most in need of help. Today you’re going to learn how to create a useful (get ready for the scary words) photoshop action. This action will help you get your photos accepted into istock and then save you hours of labor because you’ll be able to run the action on each photo you submit to istock in the future. You only have to create the action once and then it’s yours forever, or at least until your hard drive crashes. If you have never created an action before don’t worry. It is easy. If you can’t figure it out by the end of this tutorial I’ll give you your money back.

Before we start let me first explain what this action will do for you… One of the primary reasons photos get rejected on istock is for artifacting. Artifacts are the little bits of digital noise that you can spot in magnified digital images in areas of shadow or large areas of even colors (a big blue sky for example). The normal way to get rid of artifacts is to run the reduce noise filter. The problem with running the reduce noise filter is it not only removes the noise, but also reduces details. Too much noise reduction is bound to get your photo rejected from istock for loss of detail. If only there was a way to preserve details and also remove noise… That’s where this photoshop action comes in. It creates a mask that preserves details when you run the reduce noise filter. And, since it’s so easy to add to this action I’m going to show you a great method for sharpening your edges in a way that won’t get your photos rejected from istock. Let’s Begin.

Start by opening a photo into photoshop. Pick a photo with some artifacting (you Nikon shooters will have lots of photos to choose from). If you don’t have an artifacty photo, don’t worry, open any photo. It doesn’t matter all that much.

Convert the photo to the LAB colorspace (image → mode → LAB color)

Here’s where the create action part begins – try not to be frightened. First to make sure we’re all on the same page go to the top menu and select window → workspace → default workspace Now that your screen looks correct, look along the right side pallet for the little triangle that looks like the play button on a CD player. Press it.  Below is a screen shot of the fly out menu you should see now see.

Press the create new action button. This brings up a menu. In the name box type “Create Two Edge Masks” (you can name it whatever you want actually, but for ease of understanding you’ll probably want to stick with the names in this article). Now press the record button. From here on photoshop is recording every button you push so be careful to follow the next steps closely. If you screw up press the stop button (the little square) and drag your messed up action to the trash. You can then start over and try again.

Next, go to the lower right and find the channels pallet. Open it up, find the lightness channel, right click the lightness channel, and select duplicate channel.

Another menu box will pop up. Name this new channel “Edge Mask”. Click OK. You should now see a new channel at the bottom of the channel pallet called “Edge Mask”. This is not the edge mask in its final form. We will modify it and turn it into an edge mask. This channel does not effect your photo in any way. It just sits there in storage waiting around for potential use later. We can do whatever we want to this channel and it will have no effect on your photo at all. Later, we’ll turn this channel into a mask – that’s where we’re headed, and that’s why we named it “Edge Mask”.

Click on the new channel called “edge mask”. This displays the new channel and none of the others. The little eyeball icon should be on the edge mask channel and none of the others. A black and white version of your original photo should be displayed.

Now, we’re going to start turning this channel into a mask. Go up to the top menu bar click filter → stylize → find edges. After running the find edges filter your photo will be nothing but black lines on a white background. These lines are the beginnings of a mask. Unfortunately the find edges command also finds the edges of artifacts. The next couple steps will fatten up the lines around actual edges and remove the lines from areas of noise and artifacts.  At this point your photo should look something like the picture below.

Press ctrl+M to bring up the curves dialog box. We want to make the actual edges solid black and turn the artifacts white. To do this move the curves sliders to the positions shown in the diagram below. Most of the noise and artifacts live in the area on the right side of the histogram. By sliding the top slider to the left we turn all the noise white. Moving the bottom slider right darkens the black on the areas of detail in your photo. This step is an art and as you get more experienced with creating edge masks you may later want to change these curves to better eliminate noise and protect your edges.

Next we’re going to fatten up the black lines. Go to filter → blur → guasian blur. Set the radius to 2.2 and press OK.

Now you have thicker lines, but they aren’t as dark black. To blacken them up again open up curves dialog by pressing ctcl+m and adjust the sliders like the example below.

Ok, your edge mask is complete. We’re just going to add a couple more steps so you can also have a mask to use for edge sharpening. This is a two for the price of one action. Right click on the channel named “edge mask” and select duplicate channel. In the dialog box that pops up name this new channel “Sharpen Edge Mask” Click OK. You should now see a new channel named “Sharpen Edge Mask” directly below your edge mask. It will be highlighted and active as long as you haven’t clicked on anything else yet. Press ctrl+I to invert the channel. The image you see displayed should now be mostly black. If you have done everything correctly so far your channels pallet should look like the example below.

We’re almost done. The last step is pressing the stop button up on your action recorder. It’s the little square button on the bottom left of the actions fly out menu. You can see it in the first diagram of this tutorial. Once you press the stop button photoshop is no longer recording your clicks and keystrokes, and your edge mask action is saved. If you want to create an edge mask for any photo in the future just select the action you named “Create Two Edge Masks” and press the play button. All the steps will run and two new edge masks will appear as if by magic in your channels pallet. There is one caveat though for this action. Before you run it you have to convert your image to the LAB colorspace (image → mode – LAB color) or else it won’t run. If you prefer working in RGB over LAB you can convert your picture back to RGB after the action runs and you will still have the new channels after the conversion. If you’re sharp and you like to use RGB, you could rerecord the action with the transformation to LAB and back to RGB as part of the action. I mostly use LAB so I leave my photos there until I save them.

Now that we’re done you’re probably asking yourself, “What do I do with these two extra channels?” I’m saving that for part two. Did I mention this is a two part tutorial? I might have left that out, sorry. I didn’t want to scare you off before we got started. The good news is Part 2 is where the fun stuff happens. We’ve gotten all the boring but necessary stuff out of the way. In Part Two we’re going to run noise reduction and do some Unsharp Mask (USM might get its own part 3). Most of you are probably familiar with that stuff so it won’t all seem so foreign. Don’t let your guard down though. I’m also going to teach you some scary stuff like loading a selection from a channel and transforming a selection to a mask. Try to get some sleep. You’ll need it.

Part two is now finished.  Part II