How to Use Preview App on Mac

If you had to choose the most understated app for macOS, Preview would probably be one of them. It’s so closely tied to macOS that you forget it’s an app, and most of the time, when you think of Preview, you think of a part of the operating system. In fact, Preview has a lot of power in its small body, and to use a less appropriate metaphor, Preview is the sweeper in the Eight Dragons.

Preview Can Do More with Images

In macOS, the first thing many people do with Preview is to view images. But in fact, Preview is not just limited to that. When it comes to image manipulation, Preview can do a lot more, too.

Resize Images

Usually, you need to upload your photo for various kinds of exams, and there are requirements for the size of the photo on these sites; some platforms also limit the size of the image, for example, WePai requires a static 2.5MB for the maximum image size. This problem can be easily solved by using Preview.

Click the “Show Marker Toolbar” button > “Resize” > enter the appropriate size, and then OK.

Removing the Background of Image

Whenever images are involved, keying is a must. For example, when I write articles or create PPTs, I often use a lot of images, and it is my habit to take pictures myself. However, one of the disadvantages of this approach is that it often requires post-processing of the pictures. The conventional post-processing is to remove the content that affects the subject of the picture.

Click on the “Show Marker Toolbar” button in the upper right corner, then click on “Instant Alpha” (much like the magic wand in PS), then mouse click on the background area and delete it. This removes the background from the image.

View and Remove Geolocation Information

Geolocation information is a hot topic recently. For a while, the work and life of many people are being more and more talked about.

About geolocation information, in the article “Awareness first, tools second: How to distinguish false information”, I mentioned that we can use it to distinguish the authenticity of messages. With the help of “Preview”, we can check the geolocation information of these images. Similarly, sometimes it is necessary to remove geolocation information from images to avoid giving away too much information in our daily life, and we can do this easily with “Preview”.

Click the “Show inspector” button above > “More info” > GPS to view or remove geolocation information.

Creating Images from the Clipboard

With “Preview”, we can create images from the clipboard. This operation involves two main aspects, one is converting a table to a picture, and the other is saving a picture from the web to your own format.

Let’s look at the former here first. Very often, we need to save a table as a picture, and the regular operation is rather complicated. With the help of “Preview” you can quickly get the picture you want. Select and copy the corresponding part of Excel with the mouse, Command+space to bring up “Preview”, create the file from the clipboard and save it in the format you want.

Sometimes, when you are looking for images on the web, you can use “Preview” to save the images locally in the format you need. For example, some apps do not have good compatibility with webp format images, so with Preview, we can avoid the problem of this format. Copy the image with the mouse, Command+space to bring up “Preview”, create a file from the clipboard, and save it in the format you want.

Extracting App Icons

Based on “Create image from clipboard”, we can go further to extract app icons.

App icons are often used when writing articles or making PPTs. We often have to go around to find them. In fact, you can use “Preview” to extract these App icons locally.

Find the app you want to extract icons from in “Apps”, and then “Show Profile”. In the app’s profile, select the icon and copy it.

Open “Preview” and execute “File” > “New from Clipboard”. Then you can see that the app’s icon is already in the file.

Usually, we can see the app’s icons in different zoom levels. 1 We can click the info button to see the pixel situation, and then choose the clearest one to export and save. When exporting, you can choose the appropriate storage format according to your needs.

Image Color Adjustment

In “Preview” you can quickly adjust the coloring of the image. This is useful when you need to simply work with image colors, especially when it comes to solid color images, or when you need to invert the color of an image.

To do this, go to Tools > Adjust Color and adjust the color in the Adjust Color panel that appears.

Drag the slider to achieve the color you want

Manage PDF File with Preview

In addition to pictures, another major function of Preview is related to PDF. Although compared with Adobe’s Acrobat, the functions may not be as comprehensive as the latter, but “Preview” is free, lightweight, and those trivial daily routine it can almost handle.

Specifically on the implementation of the function, through the “Preview” can be rearranged on the order of the pages of the PDF file, you can split a part of the file separately or a PDF file to the existing PDF file, you can also directly from a PDF file in a specific page directly to another PDF file. In terms of personal experience, “Preview” of the degree of convenience of these operations, the smoothness of the experience than Acrobat is much better.

In the following operations when you need to adjust the PDF interface to thumbnail mode. Through the “Display” > “thumbnail”, adjust to thumbnail mode.

Rearrange PDF Page

In the thumbnail mode, you can drag and drop the pages of the PDF to adjust the page order of the PDF file.

Select the page and hold the mouse to drag it directly

Split PDF File

In the PDF file split or the extraction of specific pages, as far as I personally feel, “Preview” is much more convenient than Acrobat. Just select the appropriate page, hold down the mouse and drag out directly, you can get the corresponding page.

Append PDF Page

In contrast to the page split, we can also “preview” the additional pages. This appending of pages is divided into two cases, one is in the PDF append existing PDF files, the other is a PDF file in a specific page directly appended to another PDF file.

Select a PDF file and drag it directly into a specific location in the PDF file that has been opened to achieve page appending.

Select a specific page of a PDF file and drag it directly into a location in another PDF file to achieve page appending.

Optimize Color in PDF File

In the process of scanning physical documents into PDF format, the text color is too light is a frequently encountered problem. At this point, many people’s first reaction may be to re-scan a, or search for special editing software to deal with. But the original document may not be on hand at this time, and with this function of PDF editors are often not cheap. In fact, “Preview” comes with a “filter” can be a good way to deal with such problems.

The operation steps are also very simple: open the PDF with Preview to deal with, and then “File” > “Export …”. In the pop-up dialog box below, keep the “Format” in the “PDF” does not move, and from the “Quartz filter” select “brightness reduction” (Lightness Decrease), and then save it.

For which the brightness (lightness) adjustment, the following figure is the effect of my test. The image is a PDF file generated by my phone’s photo scanning function. The left picture is the original PDF file, the right picture for the deepening of the document.

Similarly, if the contrast of the scanned copy is too high and you want to lighten the text color, then you can choose to “increase the brightness” (Lightness Increase) filter. If you are curious about what the effect of each of the other filters is, you can refer to the image below.

In a bunch of Quartz filter options, mixed with a fancy guy – “Reduce File Size”. This is the PDF file compression. I believe that we should not be unfamiliar with this feature, here not to do too much to expand. However, from a personal point of view, such an important feature is hidden in such a small corner seems very unwarranted.

Sign PDF Document

In addition to the above-mentioned features, through the “preview” of PDF files for signing operations is also very convenient. This also does not lose Adobe Acrobat.

Click on the upper right corner of the “Show Marker Toolbar” button, and then click on the “signature” (if there is no signature can be created in the meantime), and then the “signature” has been created to drag to the designated location.

Convert Files with Preview App

In addition to these functions mentioned above, you can also convert file types between images and PDFs through Preview. This conversion includes both the conversion between different image formats, including images and PDF conversion between each other.

Open the picture with “Preview”, and then click “File” > “Export to PDF” to achieve file to picture conversion. Similar methods can be achieved PDF to picture or conversion between picture formats.

Combine Multiple Images into PDF

In the mastery of the above-mentioned methods, we can combine the above methods to form a “big move” – a multi-picture merge to create PDF. This is a variety of methods, such as file type conversion, and then page appending, thus forming a PDF file.

The above is all the features of this article, I hope you can also use these hidden features in the Preview.