can you elaborate? I thought purple pen handles this automatically. I have changed scales many times this way. Is this wrong?
The old wording said 1:15k map has magnetic lines 500m apart, and if you do not change it and change scale to 1:10k then they are 5cm apart which is a bit too much, I usually prefer something closer together. So with the old ISOM I'd often change the magnetic lines and it's always a mental effort, just one more thing to remember. Hence my base maps sometimes are without magnetic lines, hence Nitrogaine did not have them this year since I forgot to put them on.
With the new standard, it says the lines are 300m apart which works out to 2cm on 1:15k and 3cm for 1:10k, so you can just have them always at that and (mostly) forget about them.
Not sure how PP handles them automatically and then you asked me to put them on? If they are present you won't have to do anything. :)
Yes, I meant if they are already present on the base map, that it auto scales them, when you change the scale in PP. I was confused at first.
Ok, I understand now, you're talking about that actual size of how it auto scales them as a preference. I got you. I guess I don't recall off hand if 5cm feels like too much or if there's been maps like that in the past. I suppose most base plate compasses have at least a 5cm ruler, although thumb compasses probably only have 2cm usually? That's what mine has. So I could see where 5cm might be problematic there.
For me, I just prefer they be on there in most cases, as any CPs off trail to off trail, really make for anxiety when you can't take a good bearing. Also just so it's easy to figure out scale fast.
Even though I have relative experience at this point, there are still many times off trail I get easily confused by rolling terrain with subtle differences. This happened to me mostly memorably recently at Monks Rd on the streamers pre-run. There were several CPs that I was standing at, trying to figure out which way to depart to the next one and the fore view just did not visualize properly for me and I ended going off in a slightly off bearing, which then magnifies the error as terrain you go by that doesn't match you convince yourself these are the right features when they are not, or vice versa. For me when it's a particularly difficult leg, I like to take a precise bearing and confirm what I'm seeing visually. I know others are concerned with speed, I'm more concerned with accuracy (which I think was recently apparent in the Green Corn, in that our paces were not that dissimilar, it was more the magnitude of my errors). While I get this article and it makes sense for speed, I'm not at that level of accuracy for difficult legs, to be able to skip over features and recover when I make mistakes. I do try to employ this as much as possible, but I also know when to pump the brakes and make sure.
So when there are no magnetic lines and you can't properly lineup your compass, it complicates because that it what I learned on, is all that I meant. It's nice to be able to fall back to taking an exact bearing when you are really unsure of things. So I can only imagine, those who have less experience, also struggle with this and we should keep them in mind by honoring the standard.
This feels like a good opportunity to plug my idea again, that we should create curriculum based around these ideas, and offer a series of classes covering many topics. Because I'm sure there are things I do that are not ideal, perhaps even don't fully understand, because I've never had formal proper training.
Hmmm see those are items, I did not really know, but now that I think about make sense. Although, not sure about marshes, all the maps I checked for an example show them as horizontal lines.