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Datum issue?

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(@md-surveyor)
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Nevermind.....I was halfway through typing a lengthy post trying to figure out why all of our control was shifted approximately 22' compared to the ortho imagery we downloaded but, it occured to

 
Posted : 21/10/2016 5:34 am
(@md-surveyor)
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Ignore this thread, I meant to cancel it, not post it. The problem was one of our guys converted all of the opus solutions to international feet instead of survey feet.

 
Posted : 21/10/2016 5:37 am
(@nate-the-surveyor)
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Well, there is alot I could say about the Javad LS here.
You can set up 10 different coord systems, in the LS. Different scale factors, different rotations, different projections, and NEVER modify the core coords! It allows you to set that page current, (I think it is a 2 button presses) and BANG, your are looking at it in that projection or coord system. Local system, whatever...

 
Posted : 21/10/2016 6:12 am
(@nate-the-surveyor)
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It can happen to anybody... An LS as well, but you can set one page to Int feet, and one to Survey feet, and compare, without messing up the core coords. Really, it makes me want to go to college, and learn more about geodesy.

 
Posted : 21/10/2016 6:23 am
(@thebionicman)
Posts: 4438
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Nate,
Your college comment reminded me of an event years ago...
Our company was developing work flows and I hit a wall. I called Leica tech support and explained what I wanted to do. The guy on the phone loved my idea and asked what the problem was. I told him it was a struggle to express the process in standard terms so others could use it. His response was short and sweet, "Read a book".
That response stung just enough to work. My point is, there is tons of free information out there if you look for it. Read the papers on the NGS site. Look for white papers on Transportation Department and University sites. Unless you need the degree just fill your gaps with s handful of classes.
This plan isn't for everyone, but it's worth a try. Good Luck, Tom

 
Posted : 21/10/2016 7:32 am
(@nate-the-surveyor)
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Tom, you are right on target.
It's been the bomb around here.
I'm busier than I can stand. Turning away work. Wife is due any minute. With home schooling, and all, no time to fish. Daughter and son in law are here visiting.
I am not keeping up with all the Stuff that is getting installed in the Javad LS.

I HAVE bought some books. I have even read SOME of them... But, it's like driving a car, and you are too busy to stop for gas.

Fish or cut bait.

N

 
Posted : 21/10/2016 7:51 am
(@nate-the-surveyor)
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My point was that: When you FIND a problem with your SPC, and you want to check and SEE if it could have been _____ (Fill in the blank there) Say, Int feet, or US feet, you can set up a PAGE to be that item... and the RESULT is that you can LOOK, without changing the whole file. It does NOT mess up your original coord file. My point was that you can make a NON committal look, at possible solutions. One fellow I know, was TOTALLY opposed to localize... UNTIL he found out that you did not mess up your original coords... My point is that kind of freedom works very good for me.
You CAN mess things up, in an LS, and in any other computer... however, the ability to try something, without messing things up, frees up mental space. For me. In fact, I HAVE messed up lots of things. It is this non commitment to a guess, (at the problem) that lets you simply move fast.

Nate

 
Posted : 21/10/2016 8:07 am
(@thebionicman)
Posts: 4438
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I get that. After 37 years of raising kids, my last one turns 18 next week. Life will find things to fill up your time. You have to figure out what works for you, even if it means hiding geodesy books in the bathroom..
Good luck, Tom

 
Posted : 21/10/2016 8:14 am
(@james-fleming)
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thebionicman, post: 396333, member: 8136 wrote: even if it means hiding geodesy books in the bathroom

Just be careful what you store your geodesy textbooks next to in the medicine cabinet

 
Posted : 21/10/2016 8:25 am
(@jp7191)
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MD Surveyor, post: 396298, member: 10081 wrote: Ignore this thread, I meant to cancel it, not post it. The problem was one of our guys converted all of the opus solutions to international feet instead of survey feet.

I love this post! Shows we are all human, and can all make a mistake but now with the internet it can be pretty hard to take it back. Glad you figured out the problem by just beginning to compile the question. Good day, Jp

 
Posted : 21/10/2016 9:33 am
(@md-surveyor)
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Jp7191, post: 396344, member: 1617 wrote: I love this post! Shows we are all human, and can all make a mistake but now with the internet it can be pretty hard to take it back. Glad you figured out the problem by just beginning to compile the question. Good day, Jp

It really was the organizing all of my thoughts into the post that made the mistake jump out at me. It's funny how that works. One of our CAD drafters thinks it's funny that I will occasionally walk into his office and say "Just listen to me for a moment" and then I will start to talk through a problem that he doesn't have any idea about but, just discussing it out loud will trigger something in my brain that solves the problem. At that point he always says "Glad I could help" as I walk out. It's the times I walk out still mumbling Sh** that he knows we have a real problem.

 
Posted : 21/10/2016 10:01 am
(@shawn-billings)
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MD Surveyor, post: 396349, member: 10081 wrote: It really was the organizing all of my thoughts into the post that made the mistake jump out at me. It's funny how that works. One of our CAD drafters thinks it's funny that I will occasionally walk into his office and say "Just listen to me for a moment" and then I will start to talk through a problem that he doesn't have any idea about but, just discussing it out loud will trigger something in my brain that solves the problem. At that point he always says "Glad I could help" as I walk out. It's the times I walk out still mumbling Sh** that he knows we have a real problem.

I've done the same thing with my wife. Helps. Also, typing things out helps. It's handy to know certain numbers that indicate blunders, the FTi vs USFT is handy to know for a locale, but if you travel around it's not a static value. Knowing the shift from ITRF to NAD83 is handy too. When I hear 4' vertical error with GPS, my go to question is datum related. No shame in unraveling the mystery!

 
Posted : 21/10/2016 4:12 pm
(@john-putnam)
Posts: 2150
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US Feet vs International Feet, this is why real surveyors use the metric system. Try working up and down the west coast were every other state uses a different version of foot.

 
Posted : 21/10/2016 5:40 pm
(@shawn-billings)
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Metric system is for sissies.

 
Posted : 21/10/2016 6:12 pm