Most, and I mean most, of our time in the last days has been spent fooling with computer mapping. The problem, introduced a couple of posts ago, is that for parts of a long route for which you do not have a guidebook with good maps or a guarantee of good route marking at every intersection, you still need some sort of map.

The need for a map is still there even if you have GPS, because unlike in a car, you can not follow a GPS continuously. The reason is that by and large in the sun you can not easily see the screen, and you can not listen to the guidance voice if there is road noise. If you put on earphones, you may also miss the bus bearing down on you. Finally, battery power can be an issue if the GPS guidance is coming from a typical smart phone.

Ok, so maps. Actually, it's not just a map that's wanted, but a route marked out on a map. The best really is to have a GPS track marked out on a map, and the same track in the GPS device. That throws you into the world of software, usually websites, that can develop a cycle route, or display an official route, or a route uploaded by another cyclist, and then finally download a file of the same route for your GPS device.

But when that route is shown on your big monitor at home, how does it get into your map case?

Our answer has been to screen capture from the monitor and print on a colour laser. And of course, it's not one screen capture - right now we are on number 378!

Now this is where things really get hairy, and it would bore you no end to have to read the gory details. But suffice it to say there many sites that in general can plot, display, and download bike routes. The thing is, each one has subtle but critical differences. Some of the issues:

What colour is a track displayed in - too dark and it will blot out critical road numbers and names beneath. Too wide - ditto.

What file formats can the site upload and download with.

Which underlying base maps are available - terrain? roads? cycle ways?

Does the map show its scale as you zoom in and out, for consistency across many captures?

What algorithm is being used when the site suggests a bike route. Does it know what it is talking about?

If you do not like the suggested route, in part, how snarly does the algorithm get when you try to drag it around?

If it does look like you succeeded in moving a route, does the program sneak around behind you (outside where you are zoomed in to) and secretly change it?

If you use nails ("pins" "waypoints" ) to fix a route in place, how many will the program allow?

...and etc. Suffice it say that we have an "intermediate" understanding of all this, and can be heard to say stuff like " Let's take that gpx track from biroto.eu and convert it to kml. Import it into Google My Maps and reposition it a bit. Then we can export as kml and convert back to gpx using kml2gpx.com. Then upload it to the (quite wonderful) Crazyguyonabike map function where we can choose a Violet (Hi Violet!) coloured line for the track and make sure it's thin. Screen capture that and see how it prints. Oh, of course, it will print all washed out looking, so first we'll use Irfanview colour correction and set the contrast to -50, the Gamma to .83, and the saturation to +50. Since this is not our first try at developing a good map for this part of the trip, we'll name the resulting files "Orleans to Gare de Lyon final- second try 001" etc. and put them in the folder Grampies Go on Their Knees/Maps/Screen captures/Latest Ones/Even later ones/ or somesuch.

That description was a bit stylized, but it gives the idea of why our eyes are crossing.

Probably many readers will have no idea of what all this ranting is about. And many will have had similar problems and will sympathize. A certain number will have navigated on bikes all over the place with no problem. If there are any in that category, they should drop by right now to clue us in, before we go blind in front of our screens!

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