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Are all reflective targets the same?
Posted by landmanjohn on October 8, 2018 at 6:18 pmAt one end of the scale there are the really cheap no brand reflective targets on Ebay and then there’s the really, really expensive Leica ones.
I can’t afford the Leica ones. Are the cheap ones any good?
Many thanks, John
Adam1 replied 5 years, 5 months ago 7 Members · 6 Replies- 6 Replies
No they are not
I get the 40mm tartets on EBay 100 targets cost $30+, they are probably retro fitted and say Leica too.
The reflective strips found in auto parts stores to WallyMart for your trailer and other things will work just as well.
It depends upon how much you rely upon using sticky targets.
I put them on different sizes of PVC that I set around to get typical locations out of prismless range, usually fence lines. One size fits atop tpost and others fit different size iron rods and rebars and the fit the back of gammon reels on the string side.
I will half strip a card and softstick it on the corner of a building and use it that way many times.
I can plumb above a monument or measure a few straps and attach a sticker for a remote tie.
Multiple uses that an actual prism setup is more work and wasted time.
If I forget one, it is better than forgetting an actual prism.
Hey mate,
I’ve been using the cheap ebay ones for about a year now, using them as control for subdivision construction. I haven’t had any issues whatsoever with them, I’m getting the same accurate and repeatable results like I have with the more expensive Sokkia targets.
With all that said, if you’re doing high accuracy monitoring or set-out, in the realms of 1mm or less I would be using the more expensive targets to at least keep yourself covered if anyone was to ever critique your work practices. For civil construction I’ve found the cheap targets more than sufficient.
I have been cutting my own from 15 yard rolls of retro tape the adhesion seems to be much better than the cheap eBay ones. I do prefer the silk screened x on the ebay ones and will use when the can be fixed to new concrete that is very smooth or to a metallic pole. I did buy 8?x8? sheets but it seems to be the same material as eBay there is a layer of foam? That the adhesive is applied to instead of right to the back of the tape. I make a x on the tape with a oil based paint pen and punch a small dimple at the center of my x with a concrete scribe in case the marker rubs off.
My son-in-law works for a company that makes parking lot gates. He gives me all the scrap reflective tape he gets from the end of the roll.
My buddy works at a machine shop; he sharpened the end of a 1″ pipe for me. I use it to punch out 1″ disc’s. The adhesive is industrial strength. I drive by a signal pole, where I put one in 2009 and it’s still there.
I hope everyone has a great day; I know I will!I have both ‘leica’ and original sokkia ones. The price for each targets are night and day.
1. When I use the original Sokkia ones, my robot is able to automatically centre unto the crosshair of the target however for the ‘leica’ ones it is always slightly off. No problem to manually dial it in.
2. I mainly use this for quick targets during construction use where I know they will be gone in a couple of months but still useful for the time being.
3. The crosshair printed on the targets do fade on the ‘leica’ but not the reflective area after about 6 months of direct sunlight? if it helps.
I recently leared about just this topic. The short answer is no, not all prisms are the same quality. However, the major factors are the total stations specifications.
The biggest difference I have seen, between 360 degree prisms and standard 2 inch quality prism. A most 360 degree prisms have an accuracy of 5 seconds. Meaning your 1 second total station at best can measure to an accuracy of 5 seconds with this prism.
My suggestion for your situation, test your prisms. If the cheap ones return results thag are acceptable to you against the high quality prisms, then your good to go.
I tell all of my employees the same thing, “Don’t be a button pusher. Find out what its going on when you hit that button”.
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