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Question: Preview

In Apple Preview, scanned greyscale images show as solid black. Thumbnail in Preview shows correctly. What scan settings or Preview settings can correct this?

Mac mini, macOS High Sierra (10.13.1), Mac Mini OS X Version 10.10

Posted on


Dec 11, 2017 1:56 PM in response to P23P In response to P23P

Hello, P23P.

It's my understanding that your Preview app is showing your scanned images as black but the thumbnail image looks correct. I may be able to help with this but help me out, does this happen only with grayscale images or any document that you scan? Also, what type of scanner is this, flatbed or document feeding scanner? This article has a reference to why I'm asking: macOS Sierra: Scan images or documents

Scan with a document-feeding scanner

When you scan with a document-feeding scanner, the same settings are used for all the pages in the feeder. If pages need different settings (for example, some are grayscale and some are color), scan them in different groups.

  1. Place the pages in the scanner’s document feeder.

  2. Select Use Document Feeder.

  3. Set scanning options. You may need to click Show Details to see all the available options. You can choose any of the following:

    • Choose the type of image being scanned: Use the Kind pop-up menu.

      Choose Text for black-and-white images with high contrast, such as a document; choose Black & White for grayscale images; and choose Color for color images.

    • Scan both sides of a page: Select Duplex.

    • Choose a size for the scanned item: Use the Size pop-up menu.

    • Choose where to save the scanned items: Use the Scan To pop-up menu.

      If you choose a folder, the items are stored in that folder. If you choose an app, the items are opened with that app.

    • Adjust the colors or exposure of the scanned image: Choose Manual from the Image Correction pop-up menu, then adjust the controls.

      If you don’t see the image correction controls, scroll down or make the Scanner window taller.

  4. Click Scan.

    The scanner scans the pages one at a time.

Scan with a flatbed scanner

  1. Place the items on the scanner bed.

    If you want to save each item in its own file, make sure there’s empty space between each item on the scanner bed. If you scan an image that has lots of white space, the scanner may import it as more than one scanned image.

  2. Deselect Use Document Feeder, if it’s present.

  3. Choose where to save the scanned items from the left pop-up menu.

    If you choose a folder, the items are stored in that folder. If you choose an app, the items are opened with that app.

  4. Choose the size of the image or document you’re scanning from the right pop-up menu.

    You can choose a standard paper size or one of the following:

    • Detect Separate Images: Store each item in its own file and straighten crooked items.

    • Detect Enclosing Box: Include all the items on the scanner bed in one image that’s just big enough to include them all. Crooked items aren’t straightened.

  5. Click Scan.

If this doesn't help, then I would check to see if this happens using a test user account and safe mode:

How to test an issue in another user account on your Mac

Use safe mode to isolate issues with your Mac

Let me know if this helps.

Thank you for using Apple Support Communities.


Dec 11, 2017 1:56 PM

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Question: Preview