Tuesday, July 28, 2009

mapping preference

I've got a question for all you geologists out there (or whoever's left after my little blog break)...

if you have to create contours of some sort (bedrock elevations, water table, contaminant plumes), do you use software, or do you hand draw them?

I always contoured by hand, using a combination of triangulation and that elusive "professional judgement". Wherever I worked, we were too cheap to have any real contouring software, so I really didn't have much of a choice. I didn't even use simple software like surfer until I was in grad school.

At the same time, I've seen a number of astonishingly bad contours drawn by software. Here's a hint: in the real world, you tend not to have little divots and hills around all of your data points.

In the ideal world, I'd have some sort of software that would do a really basic set of contours, but that I could tweak by hand, using some sort of tablet and pen device. And the software (and peripherals would be not only cheap, but somewhat rugged.

Oh, well - a girl can dream, anyway.

7 comments:

BrianR said...

I use computers to QC and find busts, but usually prefer to hand draw for "final" interpretation ... for me, it's typically maps showing thickness of stratigraphic units

Suvrat Kher said...

used to by hand. I use GIS so now its a combination of converting point data to contours using software , but then mostly it does need some manual editing at the end.

Marciepooh said...

I have used software for a while now partly because I usually have too many data points to make hand contouring a real option. When I was doing environmental work I found Surfer did a poor job but the UST sites usually only had a handful of data points (i.e. wells), which could account for the bad contouring. The most frustrating part was that no one seemed to care that Surfer did a bad job (like contaminant plumes that looked like daisies) and I was discouraged from spending much time making the contours geologically reasonable.

The software I used in grad school (3DMove) and I'm using now (PETRA) generally do a good job but aren't cheap. I still have to fix contours by hand sometimes, usually where there are holes in the data, and that can be a pain. PETRA allows you to hand draw contours or add control points, or you can take the map into a drawing program and fix them there. Luckily I don't have to do any of this in the field. Structural cross-sections just about have to be drawn by hand everytime.

Jennie said...

you can plot contours in ArcMap and then one can import that into Adobe to tweak.

A Life Long Scholar said...

Does using Corel draw count as "by hand"? yeah, I suppose that it does. But I wouldn't do it on paper...

SilverRowan said...

on your pen and tablet comment: I can give some input on the wacom tablets. They are awesome and pressure sensitive, but there is quite the learning curve. I found the bluetooth model to be the most durable, as I had problems with cords wearing through (but as a student, those cords would be rubbing against table edges for at least 8hrs a day) My tablet is currently being held together by electrical tape, but still functions beautifully after a couple of years and some spectacular wipe-outs, however the pen is a touch less durable. I have a few (3?) due to my old tablets, and there seems to be at least 1 problem with them all. Most "eraser" problems can be fixed with some basic soldering skills though.

I love my tablet and use it all the time, and I frequently insist that they are wonderful things (mine also saves me from constant carpal tunnel)

A Life Long Scholar said...

I find the "learning curve" comment on the wacom tablet to be surprising, I recall being happy with how mine responded from the first moment I tried using it, back in '96 or so. But then at that point I was still having problems learning to use a mouse, and used key-strokes whenever possible to avoid the mouse. For some reason I never could get the hang of making such a huge item move correctly to control the tiny pointer. The pen, on the other hand, having a narrow point, made it easy for me to use. Well, that and the fact that I have the tablet set up such that if I touch the upper right portion of the tablet the pointer jumps to the upper right portion of the screen, but if I take the pen away and put it back on the lower left portion of the tablet the pointer jumps to the lower left portion of the screen. I like using a tool that actually behaves in the same manner as a pencil on paper.
The good news is that after more than a decade of using the pen, I have also developed the coordination to use a mouse, on the rare occasion I need to use someone else's computer. I may not like it compared to the pen, but at least I can now get the pointer to go where it should when I need to...