My apologies if this video is a bit too extemporaneous in delivery. My purpose is to review some key points about the T2 to make sure I have the proper understanding and to receive correction from individuals with a deeper knowledge of this equipment than I have.
Having used a T2 and T2E I am probably more familiar with the T2 and the methods behind Class I and II standards. By following these protocols it’s possible to achieve consistent raw closures of 1/million. To learn these protocols required a one term class in geodesic measurement systems using T2 and T3 instruments. Those protocols are too complex to discuss here and require a strong background in observational mathematics. Thanks for the video. Doc
We had a T2, but I only got to use it once when our total station was in the shop. It was nice to use because of the craftsmanship and quality of the movements movements, but too slow without an EDM. That was at least 25 years ago so I don't remember enough to help you.
To your final comments, when the apocalypse comes, the guy with the functional pocket scientific calculator will rule the world! Those who will be directly under him are those with the mechanical instruments and the know-how to use them. Beneath them are going to be the people with slide rules and log tables who know how to do math and science the old fashioned way!
It's pronounced like Bill. Vild. I'm a retired Land Surveyor. I worked from 1970 to 1997. Those instruments are like a Rolls Royce. Thanks for the time you put in to make this video. We had a Kern DKM1. Inverted image and a Lenker Rod. Nightmare material. Thanks again.
Im a survey student at UMaine. My professor let me sign out a T2 for the weekend. this video was extremley useful as there arnt any youtube videos specific to this instrument. Thank you for putting in the time to make this video is was a huge help!
Just bought one of these and can't wait to try it out! Love the 'ole split-bubble level! Get yourself a vintage K&E theodolite or something like that from the 1930s or thereabouts along with a vernier compass. Something without a micrometer and a one minute scale and see how it compares to this and to your total station. (Use of pocket loupes is allowed! 😁) Explore what levels of accuracy and precision are possible. I find it fascinating to find out what people of earlier eras were capable of doing (right down to learning how to do the calculations with only what was available at the time) if they were careful vs what we can do today. Often, I'm surprised by what I find! For example, I've been trying to figure out what the expected closure accuracy of a 1 minute theodolite ought to be. Clearly, you're not going to get down to 1:100000 (or 2mm +/- 5 ppm or whatever.)
I have a T2 where the index offset (offset is not error) of 3 minutes. And by doing the arithmetic reading F1/F2 it returns a Zenith angle accurate to 1 second compared to my other instruments. Reducing index offset to near zero is just convenient allowing for F1 only reading, as in topo shots, or distance reduction. For elevation determination, F1/F2 reading is always done, regardless of how small the index offset is. The vertical circle level vial is many times more sensitive the horizontal level vial. The main reason for the the ‘split bubble’ is the bubble changes size drastically with temperature. The fluid is alcohol. And as it heats up, the bubble is compressed. By using the split bubble, that change in size of the bubble has no effect.
The astronomic measurements you found mentioned aside in the Wild T2 manual are an interesting application of the instrument. I acquired a similar vintage "analog" theodolite, the Topcon model AG-30B, specifically for an astronomic calculation: to plummet benchmarks for a precise true-north line on a concrete slab for an observatory, allowing polar alignment of the telescope equatorial mount. I couldn't find any instructions on this topic, and had to re-invent the procedure. It's not difficult. You sight Polaris on the theodolite crosshairs (on a clear night), lock the horizontal angle to zero, and quickly note the date and precise time of day of the sighting. Running Stellarium on a computer, you set it to the date and time of the sighting, and it will report the azimuth angle of Polaris, which will be slightly off zero since Polaris is not precisely on the north celestial pole (this Polaris azimuth would have been calculated with an ephemeris in the old days before software methods). You apply that azimuth as a correction to the theodolite horizontal angle, and the scope now points true north, within the limits of accuracy of the instrument! You can then plunge the scope to mark two or more colinear benchmarks on the floor, aligned with true north. It occurred to me that you can use any star in Stellarium's extensive catalog for this purpose, preferably low on the horizon; you just have to note the precise time of the sighting. If you have the patience to wait to make the sighting at the time of the stars ""transit" (when it crosses the celestial meridian), then you don't need the azimuth calculation, which is zero at the transit time. Essentially, the point of light of a distant star is your surveyor's rod and turning point! You've made a primary measurement using only natural objects, without depending on prior surveys or benchmarks.
Been rediscovering our T2 (c.1980) while cleaning up. My surveying career is just at the point where this with bolt-on EDM and/or a measuring band, and astronomical observations for meridian were still in use when I studied and started work. Joyfully, we have the illumination kit and backlit targets, and with some futzing around they work too.
Many thanks for your video and the links! after 35 years of using one in the university I found a 1960 model and are now struggling in learning how to work with it.
Glad I could help! The manual is very helpful, but I found I had to read some sections several times to understand it. But, after several sessions of operation, I've found that the T2 is every bit as accurate as the very best modern total stations.
A total station, digital theodolite, is not more accurate than a T2. A total station is just faster. T2 is the best. The battery pack is mostly to accommodate night work. But in daytime it’s nice. I use the battery lighting about 99% of the time.
Thanks for the intro. This should be a fun journey. A couple of questions. Are you saying “face 1” and “face 2” or phase? Is that the same as shooting from 1 to 2 and then 2 to 1? Sorry, no civil engineering ☹️
Thanks, Potterma63! I’m saying Face 1 & 2. It means to point at the target, read the angle. This is face 1. Then turn the instrument 180 degrees, and reverse the scope and aim at the target in this reversed position. Read the angle again. This is face 2. The horizontal angle will be 180 degrees different between face 1 & 2. The zenith angles in face 1 & 2 will add up to 360 degrees. (There will be error in each axis that needs to be corrected, but I’m speaking generally.)
@20:40 is the bottom reading (2) tell you the low digit of minutes (e.g 2'43".6", 12'43".6" ,22'43".6" etc.) and you make which i is by which the upper degrees reading is it closer to?
Hi! When reading hz and vz angles with the vernier scale (not the micrometer yet) , do you confirm that your dividing mark can only fall on a tenth of gradian or 10 minute interval? Meaning that in the upper window, your dividing mark will only ever be on a line, or exactly in between a line, but never, say, 1 quarter of the way?
On some survey supply websites, the Leica NA2 auto level says "Wild Heerbrugg" on the side. www.allenprecision.com/leica-universal-series-automatic-levels
Here is the vertical bubble coincidence. The misalignment in this vid shows about 3 arcseconds. So, 1 second is easily resolvable. ua-cam.com/users/shortsnPhOZmGuTNg Note, a manual level uses the same method of leveling. Auto levels have their own set of issues. ua-cam.com/video/nut5MEGxXcg/v-deo.html I have 6 subtense bars. They’re fantastic but really tedious. At 300 feet, 0.01 feet is achievable, but takes time. To get 1:30,000 distance accuracy, the Subtense angle has to be accurate to 0.15 arcseconds. And there are procedures for that level of accuracy. In the 1950s, measuring across a rivine: definitely worth it.
I'd love to own a Wild T2. I used one at university, and in the first few years of mining. I enjoy the field adjustments that are available. I picked up Sokkia TM1A this year, which required some adjustments. The silvering on the vertical and horizontal circles has flaked off over the years, making them difficult to read.
The numbers on my horizontal circle are a bit faint, but legible. The vertical scale, which is what I really wanted the T2 for, is bold and dark, very easy to read. I'm very happy with it, overall. I tried to buy a Sokkia off a guy last year, but even though he doesn't use it, it was the first instrument he ever purchased. He couldn't let it go for sentimental reasons, which I get.
@@TheMaineSurveyor I completely understand. My wife was a little surprised when a large orange box arrived and I spent many hours in my workshop, fettling.
@@b0b5m1th I'll bet! They're so much fun! Before I got the T2, I asked the seller if the image was inverted, if it had the split-bubble vertical collimation level, and if it was graduated in DMS, grads, or mils. Additionally, if I ever buy another one, I'll ask the seller to take a photo through the microscope of both horizontal and vertical scales. It helps to get as much info as possible if buying one of these instruments online.
@@b0b5m1th Inverted. I've worked with it for several hours over the last few weeks. It's still strange aiming at the target through the inverted view. How about yours?
My apologies if this video is a bit too extemporaneous in delivery. My purpose is to review some key points about the T2 to make sure I have the proper understanding and to receive correction from individuals with a deeper knowledge of this equipment than I have.
Not at all. Great stuff.
Having used a T2 and T2E I am probably more familiar with the T2 and the methods behind Class I and II standards. By following these protocols it’s possible to achieve consistent raw closures of 1/million. To learn these protocols required a one term class in geodesic measurement systems using T2 and T3 instruments. Those protocols are too complex to discuss here and require a strong background in observational mathematics. Thanks for the video. Doc
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We had a T2, but I only got to use it once when our total station was in the shop. It was nice to use because of the craftsmanship and quality of the movements movements, but too slow without an EDM. That was at least 25 years ago so I don't remember enough to help you.
To your final comments, when the apocalypse comes, the guy with the functional pocket scientific calculator will rule the world! Those who will be directly under him are those with the mechanical instruments and the know-how to use them. Beneath them are going to be the people with slide rules and log tables who know how to do math and science the old fashioned way!
It's pronounced like Bill. Vild. I'm a retired Land Surveyor. I worked from 1970 to 1997. Those instruments are like a Rolls Royce.
Thanks for the time you put in to make this video. We had a Kern DKM1. Inverted image and a Lenker Rod. Nightmare material. Thanks again.
Im a survey student at UMaine. My professor let me sign out a T2 for the weekend. this video was extremley useful as there arnt any youtube videos specific to this instrument. Thank you for putting in the time to make this video is was a huge help!
Just bought one of these and can't wait to try it out! Love the 'ole split-bubble level!
Get yourself a vintage K&E theodolite or something like that from the 1930s or thereabouts along with a vernier compass. Something without a micrometer and a one minute scale and see how it compares to this and to your total station. (Use of pocket loupes is allowed! 😁) Explore what levels of accuracy and precision are possible. I find it fascinating to find out what people of earlier eras were capable of doing (right down to learning how to do the calculations with only what was available at the time) if they were careful vs what we can do today. Often, I'm surprised by what I find! For example, I've been trying to figure out what the expected closure accuracy of a 1 minute theodolite ought to be. Clearly, you're not going to get down to 1:100000 (or 2mm +/- 5 ppm or whatever.)
I have a T2 where the index offset (offset is not error) of 3 minutes. And by doing the arithmetic reading F1/F2 it returns a Zenith angle accurate to 1 second compared to my other instruments.
Reducing index offset to near zero is just convenient allowing for F1 only reading, as in topo shots, or distance reduction. For elevation determination, F1/F2 reading is always done, regardless of how small the index offset is.
The vertical circle level vial is many times more sensitive the horizontal level vial. The main reason for the the ‘split bubble’ is the bubble changes size drastically with temperature. The fluid is alcohol. And as it heats up, the bubble is compressed. By using the split bubble, that change in size of the bubble has no effect.
The astronomic measurements you found mentioned aside in the Wild T2 manual are an interesting application of the instrument. I acquired a similar vintage "analog" theodolite, the Topcon model AG-30B, specifically for an astronomic calculation: to plummet benchmarks for a precise true-north line on a concrete slab for an observatory, allowing polar alignment of the telescope equatorial mount. I couldn't find any instructions on this topic, and had to re-invent the procedure. It's not difficult. You sight Polaris on the theodolite crosshairs (on a clear night), lock the horizontal angle to zero, and quickly note the date and precise time of day of the sighting. Running Stellarium on a computer, you set it to the date and time of the sighting, and it will report the azimuth angle of Polaris, which will be slightly off zero since Polaris is not precisely on the north celestial pole (this Polaris azimuth would have been calculated with an ephemeris in the old days before software methods). You apply that azimuth as a correction to the theodolite horizontal angle, and the scope now points true north, within the limits of accuracy of the instrument! You can then plunge the scope to mark two or more colinear benchmarks on the floor, aligned with true north. It occurred to me that you can use any star in Stellarium's extensive catalog for this purpose, preferably low on the horizon; you just have to note the precise time of the sighting. If you have the patience to wait to make the sighting at the time of the stars ""transit" (when it crosses the celestial meridian), then you don't need the azimuth calculation, which is zero at the transit time. Essentially, the point of light of a distant star is your surveyor's rod and turning point! You've made a primary measurement using only natural objects, without depending on prior surveys or benchmarks.
Been rediscovering our T2 (c.1980) while cleaning up. My surveying career is just at the point where this with bolt-on EDM and/or a measuring band, and astronomical observations for meridian were still in use when I studied and started work. Joyfully, we have the illumination kit and backlit targets, and with some futzing around they work too.
Many thanks for your video and the links! after 35 years of using one in the university I found a 1960 model and are now struggling in learning how to work with it.
Glad I could help! The manual is very helpful, but I found I had to read some sections several times to understand it. But, after several sessions of operation, I've found that the T2 is every bit as accurate as the very best modern total stations.
If you’ve only ever been using a TS with a DC, a T2 is whole ‘nuther ball game:
Pencil and paper notes. And angle sheets for newbies is a good idea.
Aw, the old Wild T2, great instrument.
Even if you do have to stand on your head to use it! 😉
A total station, digital theodolite, is not more accurate than a T2. A total station is just faster.
T2 is the best.
The battery pack is mostly to accommodate night work. But in daytime it’s nice. I use the battery lighting about 99% of the time.
Thanks for the intro. This should be a fun journey. A couple of questions. Are you saying “face 1” and “face 2” or phase? Is that the same as shooting from 1 to 2 and then 2 to 1? Sorry, no civil engineering ☹️
Thanks, Potterma63! I’m saying Face 1 & 2. It means to point at the target, read the angle. This is face 1. Then turn the instrument 180 degrees, and reverse the scope and aim at the target in this reversed position. Read the angle again. This is face 2. The horizontal angle will be 180 degrees different between face 1 & 2. The zenith angles in face 1 & 2 will add up to 360 degrees. (There will be error in each axis that needs to be corrected, but I’m speaking generally.)
@@TheMaineSurveyor Great, thanks!
Phase one is face 1, and phase two is face 2.
Face 1, Face 2 means the same thing as Direct Reverse. Also face Left, face right, same thing.
@20:40 is the bottom reading (2) tell you the low digit of minutes (e.g 2'43".6", 12'43".6" ,22'43".6" etc.) and you make which i is by which the upper degrees reading is it closer to?
I enjoyed this
Hi! When reading hz and vz angles with the vernier scale (not the micrometer yet) , do you confirm that your dividing mark can only fall on a tenth of gradian or 10 minute interval? Meaning that in the upper window, your dividing mark will only ever be on a line, or exactly in between a line, but never, say, 1 quarter of the way?
Yes, Wild Heerbrugg became Leica, then Hexagon acquired Leica.
On some survey supply websites, the Leica NA2 auto level says "Wild Heerbrugg" on the side. www.allenprecision.com/leica-universal-series-automatic-levels
Here is the vertical bubble coincidence. The misalignment in this vid shows about 3 arcseconds. So, 1 second is easily resolvable.
ua-cam.com/users/shortsnPhOZmGuTNg
Note, a manual level uses the same method of leveling. Auto levels have their own set of issues.
ua-cam.com/video/nut5MEGxXcg/v-deo.html
I have 6 subtense bars. They’re fantastic but really tedious. At 300 feet, 0.01 feet is achievable, but takes time. To get 1:30,000 distance accuracy, the Subtense angle has to be accurate to 0.15 arcseconds. And there are procedures for that level of accuracy. In the 1950s, measuring across a rivine: definitely worth it.
Where can i get the pdf manual? I have the T1 but no manual.
Same. I'm having problems getting it level. A manual would be handy. I think I need to find someone to rebuild it.
how to clain theodolite wild T2
I'd love to own a Wild T2. I used one at university, and in the first few years of mining. I enjoy the field adjustments that are available.
I picked up Sokkia TM1A this year, which required some adjustments. The silvering on the vertical and horizontal circles has flaked off over the years, making them difficult to read.
The numbers on my horizontal circle are a bit faint, but legible. The vertical scale, which is what I really wanted the T2 for, is bold and dark, very easy to read. I'm very happy with it, overall.
I tried to buy a Sokkia off a guy last year, but even though he doesn't use it, it was the first instrument he ever purchased. He couldn't let it go for sentimental reasons, which I get.
@@TheMaineSurveyor I completely understand. My wife was a little surprised when a large orange box arrived and I spent many hours in my workshop, fettling.
@@b0b5m1th I'll bet! They're so much fun!
Before I got the T2, I asked the seller if the image was inverted, if it had the split-bubble vertical collimation level, and if it was graduated in DMS, grads, or mils. Additionally, if I ever buy another one, I'll ask the seller to take a photo through the microscope of both horizontal and vertical scales. It helps to get as much info as possible if buying one of these instruments online.
@@TheMaineSurveyor is yours an upright or inverted?
@@b0b5m1th Inverted. I've worked with it for several hours over the last few weeks. It's still strange aiming at the target through the inverted view. How about yours?
("Vilt")