One Point Localisation

I’m new to Emlid and come from a Leica background in land surveying in the UK.

I am looking to perform a ‘One Point Localisation’ and struggling to see if its even possible with Emlid.

In case I am talking Leicalese its where I have a project that is on the UK co-ordinate system and thus has a local scale factor. I then wish to create a new co-ordinate system with a scale factor of 1 and apply it, thus flattening the surveyed points.

Does Emlid have this functionality? I understand the ‘Localization’ feature is just where I can apply known co-ordinates as pairs and trying to do this with just one pair does nor work.

If Emlid cannot do this is there a third party website or piece of software that I perhaps can upload a CSV file to and perform the one-point localization.

Thanks!

It’s amazing what a person can find just by searching in Emild’s documentation:

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Do you think I would have not searched this first without taking the time and effort to create a forum post?

I suggest you re-read my post as you have clearly misunderstood. If further clarification is needed please allow me to ask in another way -

The purpose of a One Point Localisation is to create a flat grid centered on a single surveyed point. The survey point can have any Easting Northing Height value but in this case, we are using the OS coordinate system to generate an ENH. We can then use these values to center our flat grid, creating a “pseudo” OS coordinate system without the scale factor inherent in the OS coordinate system files.

Th Elmid Localization feature does not allow for this function.

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Hi @mailsurveys,

Welcome to the forum!

Localization with one point in this way is not possible in Emlid Flow. The currently supported localization indeed requires point pairs. But thank you for sharing your request! I’ve noted it and will add it as +1.

Besides, it’s also possible to create your custom coordinate system, where you can specify the scale factor, too.

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Microsurvey FieldGenius.

Lots of chinese apps if you want to go that route. I.e. Surpad, SurPro, Nuwa, etc.

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Sounds like a base shift to me. There’s no such thing as a single-point localization because of what localization entails it requires at least 3 points.

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Do you have a report? I would like to see the factors it used. I can almost guarantee it is a simple shift just like Topcon and etc do. How is it scaling and rotating? Besides we are talking about Emlid Flow so not sure how this applies.

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Yes I have done this with base shift , even if the project is out in the middle of the ocean on the map

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He asked for a third party option also. I suggest 1 that does it ALL.

Yes, it’s just a 1 point shift basically… (so base shift may work?) not a full calibration with 3 or more points involving rotation, scaling and transformation. But he is asking for 1 point localization. Just options for him to look at decide for himself what he needs if Emlid Flow is insufficient as it usually is.

@mailsurveys you can try their demos which have a 30 point limit which may be sufficient for evaluating.

www.microsurvey.com

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How’s our resident “The Great One” @EBE111057 doing? Thank you always for your professional registerred land surveyor expertise here. Most of us would be lost without you. :wink:

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10-4, missed the part asking specifically for 3rd party options. Still, Base Shift is the answer and there is no such thing as a 1-point localization. Term blunder on their part. Surveying = Keep it tight.

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Hi @mailsurveys,

I’d like to leave an update here. If you have a project in Global CS and measure a point, you can apply the localization with only one point pair using any desired local coordinates. This way, the scale factor will be 1.

Would this be a workaround for you?

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If one was doing a base shift, you can still locate the points in question and additional points and perform a least square adjustment to the project your trying to “localize” to.

It’s not a hard thing to do… many times you can do this and in effect you are performing a localization.

Newbies coming into the survey world don’t think this way. They need to understand that there’s many ways to cook chicken. I try to help people but I’m not going to do the process for them.

I was raised in this profession by my dad and he showed and taught me many things ONCE. If you didn’t catch it on the first go around you were out of luck. His method taught me to also learn from BOOKS and other ways. It was hard to satisfy him but in his eye he knew I was learning any process he described.

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Amen.

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:100: :dart:

I’ll piggy-back on that with how grateful I am to the PLS that taught me 20+ years ago. I feel like I am at an age where the percentage of people who are actually learning fieldwork the right way has plummeted. Technology is amazing but ask someone to calc some coords in a field book and come back tomorrow. I can’t certify the exact figure but I would guess off all the people in the Surveying industry in the US only about 10% are actually licensed and that may be too high. Hopefully each of those 50K are teaching at least one more person to do it the right way, but I am skeptical that they have already been swept away by the tech. Now we come full circle and I am teaching aerial mapping and more complex GNSS to that same PLS that had me dragging a chain 20 years ago.

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Thanks for all the replies. I’m a little lost what a base shift is but I will look into that. Is it just a simple easting and northing shift?

All I need is to take out the local scale factor by scaling the points. No rotation no shifting just flatten the points about a central location. The site is around 1km radius so it’s not a huge site. I have sourced where I can find the lsf so all I need to do is reverse it and I can apply that transformation within my survey software. It’s a bit of extra work but not the end of the world.

It’s just one of those things I have always had the luxury of with my old Leica for the past 15 years but now I have Emlid and whilst I am learning its limitations so far I am pleased with it (best thing being the price!)

Hi @mailsurveys,

The base shift is for cases where you have a known point on which you usually place your base, but it’s not accessible anymore. You usually need to use another, unknown location for your base, but you’ll be able to place it accurately using the coordinates of the known point. It applies both a horizontal and a vertical shift.

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