You just have to make the picture fit the measurement of the window.

Measure the finder window background size, in pixels, with free ruler Free Ruler for Mac OS X

Then open your image in Preview and in the Tools menu, do Adjust Size...

And then put it in the little box.

Fixed.

Settings>General>Accessibility>Increase contrast>Reduce Transparency. Switch it off.

Simple really. Can't remember it being like that in iOS 10 with the same settings though, but that may be just me. I thought that setting only affected the dock, etc.

Fixed.

Settings>General>Accessibility>Increase contrast>Reduce Transparency. Switch it off.

Simple really. Can't remember it being like that in iOS 10 with the same settings though, but that may be just me. I thought that setting only affected the dock, etc.

You can poke around in the accessibility settings, however it’s also possible that your iPad is dying. The equivalent of the graphic’s card is going out which is messing with the colors.

I would be sure to keep your iPad backed up in case you do lose the screen totally

It's a bug. If you swipe up too fast, the background does not blur properly.

Try swiping up more slowly until the bug is corrected on Apple's end.

There should be no negative affects, given the nature of the liquid crystal display you may see some temporary burn in also known as ghosting, but as far as permanent damage you should be fine.

If you do see a little bit of ghosting changing your display to an all white background should help to reset liquid crystals to there natural state.

~Cheers

Hi Sarah! Thanks a lot for your tip, it directly solved my problem! Never heard of this functionality, and therefore neither that it actually impacts the Safari graphics / BR Roland

There is no need to do this on either device and it can actually be detrimental to the performance of your iDevices.

In answer to my own question:

How to Change Auto-Lock on iPhone with iOS 11:

• Open Settings.
• Tap Display & Brightness.
• Select Auto-Lock.
• Set the sleep timer to the time that works best for you or select Never to turn of Auto-Lock on iPhone.

Although I don't see other of its components, this could be the cause:

3rd Party Preference Panes: ⓘ

    Flash Player (installed 2017-12-14) [Lookup]

    Rapport (installed 2012-04-25) [Lookup] <<<<<

Rapport has never worked properly on Macs in spite of what appear to be honest efforts on the part of the developer to cure its ills. Plus your version will be six years old soon. Completely remove it using the developer's instructions here:

http://www.trusteer.com/en/support/uninstalling-rapport

Adding more RAM might be appropriate but, at the time of the test, your iMac was not starved for RAM. Therefore adding RAM will not miraculously make your computer twice as fast. Yours can hold up to 32GB RAM but I suspect adding two 2GB modules (to make a total installed of 8GB) might help a little. We have an iMac and a MacBook Pro of the same time period as yours but with slightly slower 2.5ghz i5 processors. They have no issues running well with High Sierra and 8GB RAM.