@neodem You're welcome. I've been busy and unable to follow this discussion for the past day or so. Some of what I'm going to write might now be redundant, but...
You could use a level that has a horizontal circle, to measure directions to various topographic or other details — as long as the elevation change to a detail isn't too great. The level's line of sight can't tilt up or down, so the combination of the ground elevation at the detail, and the length of your range pole or leveling rod, or the height of the detail itself, has to be such that it falls into the level's field of view. In the small 200 meter x 200 meter area that you mentioned, chances are that this won't be a problem, but you should keep it in mind. A "fancy" plane table alidade will have a telescope that can tilt up and down, and a simple, sight-vane alidade allows you to angle your line of sight up or down.
A level's horizontal circle readings are rather coarse. As at least one other member noted, you might consider using a compass, like a Suunto plate compass. With good technique, your measurements might be comparable to what you could achieve with an inexpensive level's horizontal circle.
The plane table video from Scotland that another member cited is a good one. Note how simple their equipment was. In my previous comment, I suggested using a video tripod with a pan / tilt / etc head. But I'm pretty sure that the crew in Scotland were using a fixed-head, surveying-style tripod. They did all the leveling by means of adjusting the tripod's legs, and they oriented the plane table by simply turning it atop the tripod head before tightening the fastening screw.
I still think the best and most important thing for you to do right now is to do some more reading and studying. There have been good suggestions for various books. I'll add another: "Elementary Surveying" by Breed and Hosmer. It had editions from the early 1900s into the 1970s. You can find copies on abebooks.com for under $20, and there might be a free PDF on the Web for one of the early editions.
You haven't mentioned what kind of background you have in mathematics, science, or engineering. If you haven't looked at it since high school, it would be good to refresh yourself on plane trigonometry, and likewise on simple geometry.
With reading a textbook or two, and doing those math refreshers, you could start to answer some relevant questions for choosing equipment and planning your work. For example, how big a map do you envision making of your 200 meter x 200 meter area? A US Letter size sheet in a notebook? A 24x36 inch sheet that you'll frame and hang on the wall? That choice will determine the scale of your map. Then, think about the size of the smallest speck or difference of location you could discern on the map. Maybe 0.25 mm? Knowing the scale, you can translate that to a size on the ground. Then with a little trigonometry, and knowing the extent of the area you're mapping, you can figure out how finely you need to measure angles and distances. And that can help you determine what equipment would be adequate and what would be overkill.
As another member noted, you could take an entirely different approach to measuring the locations of details. Instead of measuring angles and distances, you could measure distances along a baseline and perpendicular distances from it to the details. I think you mentioned having a laser rangefinder or distance meter already. Depending on its characteristics, you might not need to buy any more equipment. Put two stakes in the ground to mark the ends of your baseline, attach a piece of white cardboard to one to serve as a convenient target for your laser, then walk along the baseline, eyeballing perpendiculars to your left and right. Shoot the laser to details on those perpendiculars, also shooting back to the beginning of your baseline. Then plot everything on graph paper. If it's not easy to shoot the laser directly to certain details, then have an assistant stand at those details, holding another piece of white cardboard as a target.
Anyway, enjoy the learning and the opportunities!
@neodem maybe you could trace a map from Google Earth? No need to survey. Kind of like what was done using aerial photos only from Google Earth, you don't need to orthorectify it because all corrections were done by Google.
@neodem I was curious about what other resources have been produced by the organization (Scotland's Rural Past) that made that plane table video from Scotland. Turns out they have a free, nice PDF book that covers plane table mapping and also baseline-and-offset mapping:
English Heritage / Historic England have a variety of free, worthwhile books:
Alidade_and_Tape_final_layouts_tagged.pdf
Not all of their books are about older methods; they also cover newer tools and methods such as total stations, GPS, LIDAR, laser scanning, and photogrammetry:
And this morning, I happened to notice an online listing for a simple, plane table alidade. It could use some clean-up, but the asking price is not very high, and the seller is willing to entertain other offers.
The level has an arc circle along the base. You could do stadia surveys with the level and rod. I did those with a T2 even after getting total stations for reservoirs cause they were actually faster. What you do is read the az, (the bottom circle) and the stadia readings. The level should have three horizontal wires to read the rod, one in the middle, one below and one above, you read all three, write them down, and you have your distance, the angle along the bottom of the level gives you the direction. From there you calculate your location (coordinate), plot the points and draw your topo. A problem with the amazon set-up is that the rod is in inches, for stadia you want tenths and hundredths of a foot. If the reading on the rod of the lower wire is 2.00 and the higher wire is 4.00 the middle wire should be 3.00 and the distance is 200'. Every extra .01' between the readings for the lower and upper wire means the rod moved 1' away. I wouldn't do it with an inches rod.
Without going into too much detail, I am suggesting you lay out an equally spaced grid marked on the ground with stakes or pin flags. The grid points are labeled as to how many feet north and east they are from the axis origin. If you use a 20 or 40 foot grid, the data points are then easily plotted on your map with an engineers scale. It becomes very easy if you have access to gridded paper.
The grid can be measured in easily with a 200 foot cloth tape. Features you want to locate then are simply measured off the grid as being xxx feet north and xxx feet east of the beginning base line. To make the map more correct, the base line can be aligned with a compass.
To get contour lines added, you shoot level rod shots at all grid points and important breaks. Once they elevations are placed on the map, contour lines are easy to interpolate.
In my early years as a survey crew member, many topographic surveys were done just this way. Some encompassed hundreds of acres.
If you use the principal of the 3,4,5 right triangle, the grid can be laid out?ÿ without a helper or a survey instrument.
This system is described in most beginner survey texts. All the gear you need is available at the local building supply.
BTW... becoming proficient with a plane table is not that easy... IMHOTI.
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Good Luck.?ÿ
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I mean no disrespect, but this board and previous iterations of it have experienced trolling such as I am positing. Call me cynical, paranoid or whatever.
I must say that I am blown away by the responses posted to your thread. Good Luck with your hobby. I used to trust this community to be virtuous and forthright in the desire to share experience and guidance, but the years have proven that desire has meant nothing in the past.
Maybe our Head Cheese and board master, Wendell, has been able to police this board to the point where none of that negative vibe and energy is getting through. Thank you Wendell!
Please, excuse my lack of faith in the land surveying community, of which I have been a member since 1972.
JA, PLS SoCal
I mean no disrespect, but....
When you start a conversation with those lines.
it only means one thing,
you mean to disrespect the other person. 🙂
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@jt50 thank you for that idea. In all the research and reading I've done so far, I think my interest lies in the surveying part and not the mapping part. I'm an engineer by trade and far from an artist so I think when I first starting thinking about this I mistakenly said I wanted to learn "mapping" when all along it was "surveying" that intrigued me the most!
@bill-c Wow. So much to dig into here. Thank you for all of your research into this for me!
By trade I'm a software engineer. I have considerable background in math and engineering so I'm fairly comfortable with the simple trig here. In fact, that's why in my first thought was that I wanted a level instead of using the plane table method. But, what you mentioned about the compass readings being course changed that idea considerably. I thought precision on the compass scale in a level was the whole point though?
For the challenge, I'd prefer to use the angles and math instead of just sighting straight lines with the plane table so I'm still thinking of heading in that direction but since everyone is insisting the plane table is the right path, maybe I should listen to all of your experience!
Here is the level I was thinking of buying. It's cheaper than a plane table setup : https://amzn.to/2HN2RJ9
In terms of the accuracy, as a software engineer I'm very familiar with the concept of iteration in design and implementation. What we do is build a super simple thing that accomplishes the goal and then we refine it over and over again into something fault resistant and of high quality. I was hoping to do the same for this map. Remember, this is just a learning experience for me. I was hoping to come back to the same place year after year and improve the detail of my map each time..
Thank you again!
@beartow Thank you so much for the offer. As this is a part time endeavor I don't know when I'll actually get into the field but when I do, I'll look you up!
@mightymoe that is super useful to know.. So the rod can be used for distance as well. I hadn't thought of that. I was planning on measuring that with a tape.
Wendell, has been able to police this board to the point where none of that negative vibe and energy is getting through. Thank you Wendell!
Stadia is a tried and true method for close work topo. Using a T2 like we did was quick and simple.
However there are some problems with using a level.
The T2 can read vertical so the way it was done was to lay the bottom wire on an even foot, read the top wire, write it down, read the middle and wave off the rodman, then write down the lower one, the AZ and the vertical reading.
With that instrument you are looking at, everything for stadia will need to be level so you can't pick an even foot reading.
But yes, most levels have three wires that will allow you to get the distance. With a typical construction 25' plastic level rod you can go to about 800' with the T2, with our wild automatic level I would say 500' is more realistic. But understand since it's a level you need the site to not have much slope or you are looking over the top of the rod, or at the ground. Of course if you can see two of the wires you can double the reading for the distance.
I have been making maps since I was six years old, some of us just like it and it led to surveying. Others became surveyors and just had to make maps.
When will we see the results of the mapping project????ÿ Curious minds want to know.?ÿ?ÿ
