Thunderbird email encryption and S / MIME

The device involves the following steps:

  1. Production of a certificate with the public and private keys in the web browser
  2. Export the certificate to a file
  3. Import the certificate into Thunderbird
  4. Configuration of the certificate in Thunderbird

On the Wiki Thunderbird, , the essential technical explanations mail encryption and signing using S / MIME.

Posted in Computer, Encryption, Encryption | Leave a comment

Possible causes for quality problems with laser printers

A poor quality, grazing on expression of laser printers can have several causes:

  1. The toner is (almost) empty.
    Then there are stripes, you are not black like other: bright stripes. This is the most common cause of quality problems.
    Solution: In this case, it often helps, the toner cartridge out of the printer to take and something to shake, distribute the remaining toner evenly over the whole width.
Posted in See all German articles, Computer, Other | Tagged , , , | Leave a comment

Demonstration of background blur by composite images

How I've calculated in my previous blog entry, is it quite difficult with digital compact- and bridge cameras thereby to highlight objects in the foreground, to make the background out of focus. Even with Aperture 2,8, who offer many good bridge cameras, is the background not so out of focus, that this an object clearly highlighted by 35 cm size.

Posted in Photography | Tagged | Leave a comment

Highlight Portraits on Photographs by Blurring the Background

It is a popular artistic means for portrait photos, to highlight the portrait, by bringing the background out of focus. If you do not care for all the technical details, but simply want to know, how to achieve it, can jumpt directly to the Results in brief jump.

Content

1. First approaches to unsharp masking

Posted in See all German articles, Other, Photography, Connect-4 | Tagged , , | Leave a comment

How does the RSA encryption work?

The question "How does the RSA encryption work?"Can be understood in two ways:

  1. What calculations are needed for the RSA-en- and decryption?
  2. Why do the corresponding formulas work?

Below I will for the RSA-en- and decryption explain the necessary calculations and then briefly outline, why these formulas work.

Posted in Computer, Encryption | Tagged , | Leave a comment