From: Scottdvoa@aol.com
Date: Sun, 20 Nov 1994 22:11:03 -0500
Subject: B maps are "real"maps
Message-Id: <941120215845_3798489@aol.com>
The only difference between an A map and a B map should be the terrain, not
the quality of the map. Your maps are your clubs most effective
advertisement of our sport. Offer your members quality maps and events
every week and you will soon find your membership growing. Two or three
good maps near your population center will be more effective than a dozen of
lesser quality. When you can get more people to your locals you can easily
justify the cost of some good photos and base maps....ed scott
From: Mitch Collinsworth <mkc@graphics.cornell.edu>
Date: Sun, 20 Nov 94 21:57:53 -0500
Subject: North America Ski-O Schedule
Message-Id: <9411210257.AA15911@toko.graphics.cornell.edu>
Thanks to everyone who sent me ski-O meet information. Info for all
North America ski-O meets I have info on can now be found on the OWWW
server under Orienteering/USA/Ski-O or Orienteering/Canada/Ski-O.
The OWWW server is at:
http://www2.aos.princeton.edu/rdslater/orienteering/orienteering.html
-Mitch
From: VJRH65A@prodigy.com (MR JAMES E HUGGINS)
Date: Sun, 20 Nov 1994 16:10:29 EST
Subject: "The Little Troll Program"
Message-Id: <013.01859240.VJRH65A@prodigy.com>
The Ark-La-Tex Orienteering Society (ALTOS) is interested into establishing
"The Little Troll Program" as another program offering through our club and
USOF. Does anyone have any experience in this area? Does the USOF still
support this program/activity? It sound like a good idea to me. Jim <H:)
From: Patrick.D.Dunlavey@williams.edu (Pat Dunlavey)
Date: Sun, 20 Nov 94 11:33:28 EST
Subject: Re: USGS data not useful for o-mapping
Message-Id: <9411201633.AB23116@hancock>
At 1:51 PM 11/19/94 -0800, Scott Donald wrote:
>I agree with Pat if we are talking about "real" A meet maps, but a lot of
>what I do is B meet maps. For those, there is no cost justification for
>the usual routine of air photos, and stereo plotting. If a local survey
>with a DLG file is available, that would be most welcome.
IF obtaining and converting DLG files to a useful form were easy and
inexpensive, I'd grudgingly agree with you. But it isn't. Does somebody
out there know something I don't?
-- Pat
From: Patrick.D.Dunlavey@williams.edu (Pat Dunlavey)
Date: Sun, 20 Nov 94 11:32:47 EST
Subject: Finding U.S. aerial photography
Message-Id: <9411201632.AB23116@hancock>
This discussion is probably of interest to many, so I'll include it to the ONet.
Finding aerial photography in the United States is a process that relies
upon equal parts luck and hard work. But first you need to know what
you're supposed to be looking for. Here's some qualifications that photos
for basemapping should meet:
Negatives are 9-inch (23 cm) square format, 78 to 155 mm focal length (3 to
6 inches, 6 inches is standard).
Diapositives (these are positive prints on FILM, contact-printed from the
original negatives). Enlargements or paper prints will not work.
Standard parameters for STEREO MAPPING (60% end-lap, 20% side-lap, vertical).
If the negatives are color, get color diapositives, else black and white is
fine, even preferable.
Photographs should be taken at a time of year when the ground is most
visible through the trees. For most areas, this is late winter/early
spring before the leaves have begun to emerge (even swelling buds can cut
down on the ability to see the ground).
The photography should be a recent as possible.
The scale of the photography should roughly match the scale of the finished
mapping, +/- 50%. For typical 1:15,000 orienteering mapping anything
between 1:10,000 and 1:20,000 is OK. Note that most American aerial
mapping firms refer to their photo scale in feet per inch, e.g. "1000
scale" would likely really mean 1:12,000.
Now, how do you find the best photography of the area you're interested in
mapping? While the USGS does have photography covering the entire country,
it is mostly pretty dated, and usually at too small a scale to be really
desirable. Other government agencies like the Soil Conservation Service
usually like to see the vegetation with leaves on, so they're not generally
very useful. Nine times out of ten, you'll find the best photography with
a private aerial mapping company. So how do you find it? A very useful
resource that is virtually free is something called the Aerial Photography
Summary Records System (ASPRS). It is available from USGS
(1-800-USA-MAPS), and you can order microfiche at $2 per state. It's a
voluntary system where all owners of aerial photography are invited to list
their photography. It's updated about once a year, so it's reasonably
up-to-date. In addition to the actual photography listings on the
microfiche, you also get some useful printed materials including a list of
all the contributors with their phone and fax numbers.
Once you've identified a potential source, it's time to rev up the fax
machine. Identify yourself as a member of a tax-exempt organization (if
that applies). Include in your letter a list of the photography
requirements (as above) and a copy of the portion of USGS map outlining the
EXACT area that you are interested in acquiring coverage of. Make sure you
write somewhere the name of the USGS quad. Finally, you ask that if they do
not have coverage to please suggest a company who they think might have
coverage of this area.
That last part is the key to this process. You could very possibly strike
out with a half dozen or more companies, but if they can keep suggesting
new ones to try, then the search is still alive. The aerial mapping
business, is a pretty tight-knit community, and they usually do not
hesitate to send business to one-another as long as it's not cutting into
their own business. They can often provide contact persons to ask for, and
that can save a lot of time.
Typical prices for black and white diapositives run around $25 each, but
it's extremely variable. Some outright refuse to sell aerial photography,
others insist that you pay a "library fee". This sort of behavior has
become less common over the past few years. Make sure that you explain
that you are making an orienteering map, and not using the photography for
engineering purposes! Most aerial photography is performed as a sideline
to businesses whose primary interest is engineering mapping. They don't
generally make money on the photography per-se, instead they make their
money by mapping. So, you might have to overcome this natural
defensiveness. If you're lucky, they will have dealt with orienteers
before, and be relaxed about it. So... when you get your bill - PAY IT!
I'll be happy to write explainations of other parts of the mapping process,
either for general consumption or "offline".
Pat Dunlavey pdunlave@williams.edu
{dba Pat Dunlavey Cartographics, TopoMagic}
40 Oblong Road, Williamstown, MA 01267
voice (413) 458-9836 fax (413) 458-9273
From: joseph.huberman@mms.raleigh.nc.us
Date: Sun, 20 Nov 94 11:05:28
Subject: USGS DATA NOT US
Message-Id: <9411201105.0FKXI00@mms.raleigh.nc.us>
-=> UA145@CIAO.TRAIL.BC.CA wrote 11-19-94 regarding RE: USGS DATA NOT
US <=-
U>I agree with Pat if we are talking about "real" A meet maps, but a lo
U>what I do is B meet maps. For those, there is no cost justification f
U>the usual routine of air photos, and stereo plotting. If a local surv
U>with a DLG file is available, that would be most welcome.
U>
U>Scott
The super high quality map that we have become accustomed to at "A"
Meets is our most important tool for attracting new members. I think
the quality is more important for the local meets, particularly since
it makes setting courses *much* easier improving life for our
volunteers.
Joseph Huberman
Treklite Inc. Orienteering and Outdoor Equipment
904 Dorothea Drive, Raleigh, NC 27603-2140
Phone - (919) 828-6068
InterNet - Joseph.Huberman@MMS.Raleigh.NC.US
11/19/94
From: Knut.Wiig.Mathisen@hrp.no (Knut Wiig Mathisen)
Date: Sun, 20 Nov 1994 10:50:32 +0100
Subject: Spikes in Mass starts
Message-Id: <9411200951.AA10850@merckx.graphics.cornell.edu>
I think modern everlasting round spikes involve no danger to orienteerers, even
in mass starts. Some years ago several runners were severly cut from spikes,
but these incidents were (to my knowledge) all caused by old, athletic
type extremely sharp and long (12-15 mm) spikes that you would wear out and
had to change every 2-5 races. (Typically in Tiomila and Jukola most runners
would use new spikes for maximum grip).
After everyone has started to use the modern,
very hard steel spikes with rounded tips, I haven't heard of anyone being
injured.
Unless anyone out there know better, I think one should ban sharp spikes, not
spike shoes in general. Not even on first legs in the big relays.
Knut W. Mathisen, Halden SK