My coin process in Photoshop (3MB+ of large pictures)

We all have different processes of capturing coins. There's no such thing as "the right way" to get to the end result. Those with more photography skills tend to concentrate on taking multiple shots, adjusting lighting, etc., whereas those of us with less photography skill may compensate by way of image editing.

The bottom line is to use the tools and techniques that *you* feel most comfortable with and that get the job done in the most effective manner.

I thought I would outline the steps that I use for my finalizing my coin shots. I'm familiar enough with the image editing process now that I've gotten to the point that it takes about 1-2 minutes per picture from start to finish; fairly speedy.

The software I use is Adobe Photoshop CS for Windows.

I photograph in batches, 10-20 coins at a time. I usually take 2 or 3 shots per coin side, changing only the exposure. Once I copy all of the pictures to my PC, I'll load the 2-3 images into Photoshop at once, tile them, and choose the one that looks closest to coin in hand as a starting point to work with. I then close out the others.

Note: you may see some disparities between the screen shots and the final images I show, because the screen shots are done as GIF files, whereas the coin images are JPEGs. Computer screen captures render better as GIFs...

Here's the raw image from the camera loaded into Photoshop:




It looks fairly washed out and too brown compared to coin in hand, but we will fix this.

First thing I do is to crop the image, so I'm working with fewer pixels throughout the remainder of the process, which speeds things up.

I select the crop tool from the tool palatte:




At the top of the work area there is an attributes bar that shows the various parameters of the currently-selected tool. I like all my pictures to be exactly the same size, 500 pixels square, so I set the width and height fields to "500 px". The purpose of this is twofold: (1) the cropping area is constrained to a perfect square, and (2) whatever area I outline, upon cropping, will be resized automatically to 500x500 pixels. This is a MAJOR timesaver.




Selecting the area to crop:




After cropping:




Now a bit of tweaking. First, I find doing an auto contrast helps immensely; it removes some of that "washed out" look. This is done by going to the Image menu and selecting Adjustments > Auto Contrast. I prefer to learn keyboard shortcuts for all of these steps. The keyboard shortcut for this step is Ctrl + Alt + Shift + L.




The results of doing the auto-contrast step (the effect is more or less subtle on different coins):




Sometimes doing an Auto Contrast makes the overall cast of the coin darker than I really want, obscuring some of the details. While I don't necessarily think it is necessary for this particular coin, I will go through the steps to rectify that anyway.

If the Auto Contrast results in a coin that is too dark or shadowed, I set the levels, specifically lightening the midtones. This is done by Going to the Image Menu and selecting Levels. The keyboard shortcut is Ctrl + L.




This brings up a poup box like the one below with a levels histogram. The only tool on this screen that I will be using is the center triangle below the histogram. Moving it to the left will lighten the midtones without affecting the highlights or the shadows. I can drag it around and see the changes live; my changes are not committed until I click OK. If I want to compare what my changes will look like with the way the coin was before, I can uncheck and recheck the box next to Preview which will toggle the views.




For the sake of this exercse, I am going to lighten the midtones slightly, which results in the following:




The next step is to adjust the color cast of the picture. It's too brown, and not as red as the real coin. For these adjustments I use the Variations feature, which gives me a visual color balance palette to work with. From the Image menu, select Adjustments > Variations. The keyboard shortcut is Ctrl + Alt + V.




This brings up a screen showing the image as it is, along with variations in all directions.




Now obviously the shifts in each color direction are too much. By shifting the slider at the top of the screen to the left, it makes the shifts more subtle. I like to use a setting of one from the very left, which results in the following screen:




The changes I make on this screen will combine, i.e., if I click once on More Magenta it recalculates and redisplays all the coins so I can then go off in another direction. This allows me to "home in" on a desired color cast. None of the changes are committed to the image until I click OK, so this is a great way of experimenting. For almost all coins, I find that a single click on More Red is adequate.

In this case, it results in the following:




The final step is to delete the background to white. To do this I use the Magic Wand tool:




Once the tool is selected, I want to adjust the Tolerance field in the parameter bar at the top. I find that a tolerance of between 12 and 20 works best. This will vary from coin to coin. Copper and brass are easier to work with, since their color naturally contrasts more with the dull grey of the background. On silver and nickel this becomes a little trickier because the color tone of the coin is closer to that of the background.




Now I want to set the color to delete to. I like solid white, but I could choose black or any other color. I like white because (1) it doesn't skew the perception of the coin, and (2) any antialiasing effects at the edges of the coin fade easier to white than a solid color.

To set the color to delete to, click on the rightmost of the two large overlapping squares at the bottom of the tool palette. This bring up the color definition dialogue box below. I can either define the color numerically or simply click on the color in the area at the left.




Now that I have the color selected, I click in the background area of the coin. A dotted area appears showing the selected area of contiguous pixels within the tolerance range of the pixel I clicked on. I can adjust the tolerance and reclick to see what effect numerical adjustments have on the selected area. I want to pay attention that I am selecting background only and not elements of the coin. This is tougher than it sounds, especially on lustrous silver coins where portions of the rim come close to white. I don't have to get all the background in one step, just large contiguous chunks.




I can now delete to the chosen color by simply pressing the Delete key.





You can see that the dotted area is now all white. Now I click in the background on the other side of the coin to select the remaining background area to delete to white. As you can see, it selected the entire background, including the area I already deleted. This is not uncommon and does not cause a problem.




And now I press Delete again and I have the result below.




Now all that's left is to save the image. From the File menu, I select Save for Web. Keyboard shortcut is Ctrl + Alt + Shift + S.




This will bring up a preview dialog box showing a preview of the picture optimized as either GIF, JPEG, or PNG. By adjusting the level of JPEG compression or the size of the color palette for a GIF, I can preview what the image will look like. I like using JPEG with a quality setting of 50.




One last thing to do before I save the image. See the little black triangle pointing to the right within a circle at the upper right? I want to click on that and make sure that Use Document Color Profile is selected. Otherwise the image will render differently in different browsers and on different computer platforms. This was driving me nuts until I discovered this setting was the culprit -- I was seeing the images display slightly differently in Microsoft Internet Explorer as opposed to Netscape or Firefox.




And here side by side are the original image and the final result. The differences aren't as stark as they are on most coins, but you get the idea...