# Tech blog

### This blog is for my future and past info and reviews on various tech stuff….

 Phones / Phablets Compact cameras Various tech stuff Reviews Resolution and Noise Batteries and usage PC Code examples Math Other stuff

Newer reviews can be expected to be ongoing projects, with minor additions or corrections.

Note: When I rate stuff, a 10/10 does not indicate perfect in an absolute academic sense, but as in (at least) as good as could be expected at the time, minor flaws allowed. For portable devices typically limited by the size and weight. Value for money also counts. An electronic device that got a high score in 2005, most likely would seem like pure trash ten years later….

• Length of round (carpet) roll

For some reason, surprisingly few know this extremely simple formula, please share it.

I have actually seen in a carpet store an employee unrolling the carpet to measure the length!!

[The formula is simple to prove too… r=kφ, L=∫r dφ=∫kφ dφ=½k(φ2²-φ1²)=½k(φ21)×(φ21)=½(r2+r1) ×n2π=(r2+r1) × nπ , q.e.d.]

• How to wait upgrading to Win10

If you do not want to be a first mover installing Win10, then this link have the recipe to delay it

(A few windows update should be uninstalled if already installed, and then hidden until you want them)

• Eye resolution test

I have made a simple test image to test the resolution of your eyes on a phone, phablet, tablet, laptop or PC!

The most common result is it is pointless to go beyond around 1/12000 of the viewing distance

Be SURE it is shown in the screens native resolution. e.g. 960 pixels should fill half a FullHD display. (or use one of the added ones with your screens resolution)

Be SURE that your browser or your windows settings doesn’t do any scaling/zooming/smoothing, i.e. one pixel in the image is one pixel on the display. (If in doubt take a magnifying glass -or macro camera- and look closely on the screen, it should be like the mock-up later in this post)

It is the point where the single line pair is indistinguishable from the double line we are looking for (that is where it is looks like one continuous thick line)

You will most likely find the finest resolution using the red or green figure.

Use any prescribed glasses that you normally would for the distance – we are testing resolution, not focusing ability.

NOTE: If you got a PenTile display, usually the green will do fine! Have a look at this on different subpixel arrangements. Several pixel arrangement exists out there, that could have similar issues…

• Principal ideas for smarter image sensor technology

Currently the limitation in the amount of photons that can be caught versus the noise, set a limit for the dynamic range.

But what if the sensor output could not be over saturated?

• Automower 330X, Husqvarna, Review

This Automower 330X is an upgrade from my 230ACX, See review here.

# Overall: Really satisfied. 9+/10, after software ‘update’: 7+/10

It is rather similar to the 230ACX with some important upgrades, and a few step backs