You might not select only the iris when using the elliptical marquee tool, but also some parts above or below then. Switch back to selecting the Lasso tool and holding down the Alt key, drag around each area you did not want to select (by holding the “Alt” key, you will be using the “Subtract from selection” option). You will see that each time you release the mouse button, the respective part of the selection will disappear.

At this point you will only have the irises selected. You need now to copy the iris in the both eyes to a new layer. But before this, you should soften the selection. Go to the “Select” menu found at the top of the screen and chose “Feather”.

In the “Feather” dialog box, enter a value of around 5 pixels and press “OK”. Click next on the “Background layer” (select it from the Layers palette). Press Atrl+Alt+J on the keyboard to copy the selection onto a new layer above the “Background” layer. Rename the new layer “dodge”.

You will applying an Unsharp Mask filter to the “dodge” layer. Make sure you have the “dodge” layer selected and go to the “Filter” menu at the top of the Photoshop main window and select “Sharpen” and then “Unsharp Mask”. Use an “Amount” value of 500%, a “Radius” value of 2 pixels and a “Threshold” value of 4 levels.

Because after all these settings done, the “dodge” layer’s sharpening is too strong, reduce it to 50%.

You will now add a highlight in the lower right corner of each iris. Use the “Dodge” tool (select it from the Tools palette or press the O key). At the top of the screen you will see the “Options bar”. Modify the “Range” value to “Highlights” and the “Exposure” value to 50%.

Select a small soft-edged brush (its size should be around 10 pixels, again, depending on your picture’s size). Paint a few strokes in the bottom right part of the iris. You will see that with each stroke you increase the amount of highlight applied to that area. Be careful not to exaggerate, especially is there was some highlight in the iris to start with.