Wimmel mit! From analogue to digital – Scanning 101

Wimmel mit! From analogue to digital – Scanning 101

Scanning 101

When I start an illustration project I begin with one or perhaps several sketches. Sometimes I illustrate completely analogue, but then the question arises about producing a print-ready file for it.

From my experience as a design teacher, I know that many students shy away from scanning. Their scans often have a color cast or they don't know how to scan the whole image because "the picture was too big for the scanner". This does't have to be; if you know the correct settings and take a moment to get to know certain functions of the scanner, you can learn Scanning 101.

That is what we going to talk about today. I am going to show you how to convert an analogue image that does not fit on the scanner into an editable file. For my experienced clients and colleagues who are read my blog, today is really for beginners, but I'd be happy if you continue to read anyway.

Even if cleaning isn't your thing, cleaning your scanner before each scan will save you work in the end

Neatniks have an Advantage

Those who tend to be part of Team Chaos must pull themselves together. You need to clean up now – but only the scanner's glass surface. (Don't worry, everyone else has to do that, too)


Even though the lid of the scanner is usually closed, tiny dust particles can find their way onto the glass. In addition, you can inadvertently leave fingerprints on the surface even if your hands are clean.

During your scanning session you will have to repeat the cleaning process before every scan. Without exception. The cleaning helps avoid later work in Photoshop because you won't be scanning dust particles and fingerprints in with your image. I speak from experience, this extra effort in Photoshop is preventable and these small particles can cause extra unpaid work.

Please don't use a window cleaning fluid, it can leave streaks. It is best to use a lint-free cleaning cloth with a few drops of isopropyl alcohol. Eyeglass cleaning towlettes can do in a pinch, but in the long run they are more expensive and worse for the environment.

Planning your scans with imaginary borders helps Photoshop stitch your image back together seamlessly

But the Glass is too Small... 

Of course, a scanner built for documents in the size of 21 x 29.7 cm (8 1/4″ x 11 3/4″) does not provide enough surface to scan a larger image in a single operation. But it is possible to scan several sections of the image and put them together in Photoshop. You have to plan a little in advance.

I calculate an imaginary frame around the glass surface of the scanner. Everything I scan in this frame area is actually scanned twice to give Photoshop a way to detect the image. The frame is used as an overlapping area when put back together.

In this photo you can see that my sketch was drawn on transparent paper, it is easier for me to see the glass surface and the overlap area. This allows me to see how straight my image is lying on the scanner.

But even if you scan a finished illustration, you can use a few hacks to help you scan. Sometimes I tape some masking tape to the scanner at the level of the edges that have to overlap. Then I make a pencil mark on the back of my picture where the glass and where the overlap area is. I can erase these marks later. I put large washers (you can get them from the hardware store) on the back of the image as a weight so that the paper does not slip or curl and remains flat. I wouldn't use them when I scan in a sketch on tracing paper, because the washers would show in the scan.

Even an A4 Document sized scanner can handle oversized scans if you take some time to learn how.

Shut the Lid and Scan

Just close the lid, because now it's time to scan.

For this illustration I made six (6) scans. Each scan takes about 5 minutes, sometimes longer if the paper is really big and being stubborn. Seldom less.

Choose Professional Mode and TIFF as your format and set the resolution to 300 dpi.

Even Scanning has to be Learnt

As a basis for this post, I used my sketch for "Wimmel mit! The Online Wimmelpicture Project", which is 35 x 49 cm (WxH)(13 3/4" x 19 1/3") big - too big for my A4 scanner to digitize it with a single scan.

What many beginners-and non-beginners do not know is that most scanners not only have an automatic mode, but a professional mode, too. My first scanner from Epson, which was an inexpensive model, and my new Epson Perfection V600 photo both have professional modes.

Since I want to create a high resolution editable file, I choose the professional mode. In the professional mode you have more possibilities of determining the settings for your scan.

For this scan, which is a sketch I'll illustrate in Photoshop, I choose the bit color depth '24 bit color' and a resolution of 300 dpi. I'd like to mention: If I had to digitize an analogue illustration, such as a watercolor, for a larger print format than the original, I might scan it with 600 dpi. But this is not the case, because the sketch is larger than the size of my print product. And a larger bit depth is not necessary for any print product.

I choose the 'unsharp mask' option to sharpen the sketch. Yes. I know. The term sounds confusing and contradictory, this process makes the image more clear by increasing the contrast in certain areas of the image. A rasterization of an original illustration or drawing is not necessary. We aren't scanning a finished print product. This setting minimizes the raster and moiré effect of printed images that are being scanned.

Last I choose the file format. I'll be editing the sketch in Photoshop, but the scanner cannot save the image as a psd file. I choose TIFF because this format provides a better result than JPEG.

Pre-scan using Preview (in this picture ‚Vorschau‘) Leave a generous border around your image for the scans to overlap in Photoshop.

The Scan before the Scan

Before I click and scan and save, I create a pre-scan that shows me what I'll see in this section of my sketch.  In this example, I not only have two edges that will overlap the other scans later, but I also make sure that the borders of the scanned image are wide enough. You'll see why in a moment.

When I am satisfied with the result of the pre-scan, I scan to file.


If your computer RAM allows it, you can open all the scans together in Photoshop

The next Stop is Photoshop

From an oversized image I made six scans that have overlapping areas and wide borders. To create a work file, I drag all my scans directly into Photoshop. Warning: Your computer must have enough memory to do this, otherwise it could crash. There's a second method that I'm going to explain to you in a moment.

This Warning is Harmless

This Warning is Harmless

This warning can unsettle a beginner. Don't let yourself get confused. It provides information about the current color gamut of the document and the color gamut that is set for the Adobe programs.

Nod and Click OK.

You can change the color gamut later. In fact, it's better that way. In a later blogpost I'll show you how.

The Adobe sRGB can display more colors than the Epson sRGB or the normal sRGB color gamut. Not all output devices can represent nor reproduce the Adobe sRGB color gamut.

Once you realize that you can deal with color gamut at a later stage, you just have to accept the warning

Wave the Rest Through

As in the previous picture, just click on 'OK'. We'll take care of the color gamut in a later blog post. Repeat this step for all scans.

Photoshop offers a powerful time-saving tool called Photomerge


When I first started out, I had to put my scans together in Photoshop manually. That was a very elaborate work. Today, this is much easier and more convenient with the automation function in Photoshop.

Select File > Automate > Photomerge. A new window will open.

You can edit the Photomerge settings in a separate window and add the scans to be stitched together

Marrying the Scans

Since all of my scans are already open in Photoshop, I just have to click on 'Add open files'. Be sure to put a tick on 'blend images together'. Leave the radio button in the layout at 'auto.'

If your files aren't already open in Photoshop, you only need to click ‚browse‘ to add them to the list. I'd recommend this if your computer is a little older or does not have as much working memory (RAM) as you would like. However, the scans must all be facing in one direction to successfully stitch the image together. If not, you should set them up in advance.

Although Photoshop marries the scans seamlessly, it is often rough around the edges

Photoshop works Its Magic

While Photoshop stitches the picture together, you can go ahead make me some coffee. Actually, Photoshop is pretty fast, so there won't be time to brew any coffee.

Do you see how the edges look a little crooked and unclean? This is the reason I leave a wide border when scanning. It is easier to remove something afterwards, but what is not there cannot be added or added only with difficulty. We'll turn the sketch in the next steps.

An obvious, albeit underestimated step is saving your file to the correct format

Save your File. Often

Before the image is rotated for further editing, it should be saved as a Photoshop file. Remember: Save it often using COMMAND + S. If the program crashes, then the work won't be completely lost.

Choosing the optimal file format is key to your further work


Everyone knows how to use hashtags in social media. You can do something similar with your own files on a Mac. This is easy with the 'tags' tab. The advantage is that if you are looking for a specific illustration or sketch at a later time, you can enter a keyword in the Finder and speed up your search.

Since this picture is wimmelpicture for Wimmel mit! The Online Wimmelpicture Project, I use related tags like wimmelpicture, wimmelbook, Wimmel mit!, sketch, illustration, etc.

My scans are married, but, they aren't supposed to be on their honeymoon

Rotate or Help! My Picture is Upside-Down!

My picture is sideways. To use it for a print file, I need to upright it. To rotate the file, I use this path: Image > Image Rotation > 90° counterclockwise.

Of course you can enter a different rotation angle. If you chose the wrong angle you can always use command + Z to undo the rotation. You can also use the protocoll window: Just drag the command into the bin.

Once the scan is uprighted, the real work can start.

È voila!

Hurrah! You did it! And the image is standing upright like a soldier. Now look at the layers window. Here you can see that Photoshop has masked parts of the individual scans. To reduce the file size somewhat and to create a clear structure, I recommend merging these layers together.

There are a few ways to do this, either

  • Layers > Merge to background layer
  • Layers > Merge visible

The advantage of the merge to background level is that the layer is automatically locked and therefore cannot be edited accidentally. ‚Merge visible' allows immediate editing.

I usually choose the second option and create a background layer and fill it with white. I create an empty transparent layer above my sketch and lock my sketch.

And now the image can be edited in Photoshop. Join me in my next posts to see how I create a wimmelpicture.

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