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Another Javad convert  

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Nate The Surveyor
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Actually, with a bipod, I do leave the point, go to lunch, and come back, to find a nice cluster of shots! (But you probably meant, taking the LS with you).

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Tom Bushelman
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I meant that my I would be charging more for what I do with newer and better equipment. 

Through discussions and hearing the opinions of real gurus, I've been told that 20 minutes causes enough of a constellation change to validate a new shot with different multipath conditions.  I have not run into a situation that required that sort of redundancy yet.  After the day is done, the points have been submitted through DPOS (Javad specific post-processing), you can look at all, and I mean all of the data pertinent to a point that you shot.  If you have a pin that does not lay in where it should on the plat and you start second guessing the validity or accuracy of the shot, you can look at the data, see how long you were on the point, how many epochs were collected, I believe you can even look at each satellite that was used.  I am skipping over some of the pages of data available, but it is a very detailed set of "fieldbook notes" so to speak, which can give you a warm fuzzy feeling about it or know to go back and shoot it again.

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Duane Frymire
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20-30 minutes is a good ballpark for really tough conditions.  But with even moderate sky view constellation changes enough now days in 3-4 minutes.  Validate being an 2 engines solution redundant repeat within 0.13' in my testing.

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Norman Oklahoma
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"....I've been told that 20 minutes causes enough of a constellation change to validate a new shot with different multipath conditions...."

I read several sources on this subject including one that mentioned the 20 minutes recommendation.  It's not a direct mathematical relationship. What works is going to depend on the multipath conditions present at the site and the orientation of the constellation of the moment. 20 minutes is always going to be better than nothing, 2 hours is always going to be better than 20 minutes, and 6 hours is going to be about optimum - given the +/-12 hour orbital period of the satellites.    

I'm not saying that you need to tie everything twice, time offset. But it is something worth doing if higher precision is wanted.

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Rover83
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Agreed. If I remember correctly, that 20 minute recommendation is for network RTK, not single base, and assumes multi-constellation tracking under ideal conditions, i.e. upwards of 12 SVs tracked and used in solution.

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MightyMoe
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Multi-path geometry can be changed rather quickly in timber/brush areas. Slide the rod up or down and the geometry changes. I've never been able to get two bad locations on a point that matched. Two locations that are different make me reject both locations until I know otherwise, but if they both check with different fixes and different multi-path geometry I start thinking that I have something.

On another note, I either seem to be able to get a shot with the R10 or not. I've not been able to get a bad shot with one yet, all my independent checks on points have shown the R10 locations were good, even in very bad brush, timber areas. If it won't take a shot I will either try at a later time or break out the robot. Sometimes both, I've struggled with the 4400, 4700, 4800, 5700, 5800, but not the R10. The R8 is good also, just not as good as the R10 in timber.

I figure the Javad is similar, but I still have memories of the old days where bad fixes were a daily occurrence.

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Stephen Ward
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I just got a base & rover set of R10-2's.  They are phenomenal in full canopy and the internal batteries are lasting close to six hours on the base while driving the internal radio at full power. I also have yet to get a bad shot. They're  good and repeatable or it will cry foul before you're allowed to store the shot, at least that's what I've seen so far.

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Plumb Bill
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I got a bad shot just last week.  Brand new and updated base/rover R10 pair.  But this was possibly even more difficult than canopy, it was next to a 10' tall ballistic security fence.  The distance between the "store another" was 25 feet!  That's the worst I've seen in some time.  I stayed well away from the fence after that and broke out the S7 for those locations.  I too, though, have noticed it's nearly impossible to get the same bad fix twice in canopy.  I wouldn't say it CAN'T happen, but I've yet to see it.  In the deep dark hollers of SW VA there's still plenty of places an R10 won't fix at all.  Forget trees, sometimes dirt and rock are blocking half of the sky.  I have noticed that the more birds go up the point of failure gets deeper and deeper in the holler.  I chuckle when I read from some people "more than 20 doesn't help accuracy at all".  Forget accuracy (a foot is usually good enough for LOD), I'm trying to overcome multipath - and it sure seems like the more the better.

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MightyMoe
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It was fixed? I know fix is different with an R10, I can store points with bad geometry all day long, but they aren't good points that I would trust. 

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Plumb Bill
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Yes it was fixed.  I was surveying rapid with auto-store once fixed.  My SOP is to count the number back and "store another" to review the deviation between the two.

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Nate The Surveyor
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@plumb bill

"there's still plenty of places an R10 won't fix at all."

I have yet to find a place I cannot get the shot. I suppose I could put aluminum foil on it, or stick it under a carport, up against the inside roof.

When I say "a shot", I mean a verified, and for real shot. I described this elsewhere.

The proof is always in the pudding.

N

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Norman Oklahoma
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These Javad threads always have a P&R feel. Tribal. 

Hey - Javad is great gear, at a great price point, and they give great customer service. Along with a healthy dose of propaganda.  Leica, Trimble, Topcon, and several others are also great units. They all solve multiple, concurrent, redundant fixes in one fashion or another.  That's been a thing for quite a while.     

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Nate The Surveyor
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These Javad threads always have a P&R feel. Tribal.

Whell, ok, I feel like a kid may have felt, in 1820, who just rode the train to Boston. It beats walking.

And, the sights are amazing, to this country boy.

N

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BlitzkriegBob
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That definitely would have been quite a feat since the first passenger railroad didn't run until 1827!

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Nate The Surveyor
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Yer hurtin me. 😉

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Jim Frame
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These Javad threads always have a P&R feel. Tribal. 

I think that's because the typical user of the Triumph-LS is new to current-generation receivers.  He may have some experience with older equipment, but may also be new to RTK.  He's a small-time operator for whom the price point is important, and has been skeptical about the value of RTK.  As a result of all this, he tends to be quite impressed with the performance of the unit and therefore likely to sing its praises.

This doesn't describe all Javad users, of course, but it captures a lot of them, including me.  I'm not suggesting that our enthusiasm is misplaced, but it does take on a tribal feeling at times. 

And the  platform is truly different from the rest of the pack, as is the support model, which offers a pretty direct connection between end user and developer.  Javad Ashjaee himself even weighs in on support threads now and then. (I've had some experience with Trimble support over the last 20 years, and the difference is stark.)

 

 

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Rover83
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Good points. And on the opposite end of the spectrum, consumers tend to expect much more of the larger manufacturers (higher price point and marketing help with that), and because they have been around for a while with ups and downs, users tend to be a bit jaded. Add to that the variability in support due to regional differences...

Having worked tech support and training for one of the large manufacturers, I interacted with numerous individuals who had some wildly unrealistic expectations of their equipment, especially GNSS. It's hard to please everyone, and it's especially hard to convince everyone that there is no single perfect workflow to get perfect results every single time. Most people don't like being told that their expensive new toy still requires a high level of technical knowledge, and careful judgment about when and how to use it.

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Nate The Surveyor
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@Norman Oklahoma

"Healthy Dose of propaganda"

I don't really think so.

If you took your favorite GPS into impossibleville, and set it up, let it get a fix, stored that fix with a temporary name, then, turned the pole over, loosing lock, then set it back up, and did this 10 to 15 times, (in challenging location, this could use a lot of time), then, took the average of the statistically strongest group of temporary coords, and used this for your init position, then gathered for several more minutes, and then flipped your pole over several more times. To double check the init location. If this test fails, then start over. If it passes, then you save the coord. To attempt all this checking with any other scheme would be difficult.

Whereas, this is a brief summary of one boundary shot, and all the above is automated.

Observing multiple times, ONLY refines this coord, by hundredths. It has a weighted average program in it, which is quite good.

I have heard of one instance of the above coord being wrong by 0.8'. Another user was set up against a 30" tree, and it gave an answer that was wrong by 0.8'. The surveyor (as is his practice) re-shot it, found the 0.8', then observed it a couple more times, to be sure.

So, any time I'm close to a tree, I observe multiple times.

I personally have NEVER gotten a wrong init.with the above system, that's fully automated. Believe me, I've tried to break it.

So, the reaso we like it, is it works. Propaganda is NOT a part of this. We flushed propaganda long ago. That's WHY we bought Javad. I thought on this a while before posting it. Propaganda is NOT something we like.

Ps... I'm just a user. Unpaid.

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Norman Oklahoma
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Perhaps you just don't like the word. But a rose by any other name would smell as sweet..... 

Simultaneous parallel solutions have been a routine thing for 20 years at least. Not unique to Javad. Your Javad is a good unit at a good price and I'm glad you like it. It is undoubtedly significantly better than earlier generation units, particularly GPS only units held together with multiple layers of duct tape. But  that's all it is. Modern units sold by other major vendors are as good, or very nearly so, and in some cases better.

You've got a good unit there, Nate-ster. But it's not a box full of miracles.    

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Duane Frymire
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Smells like stuffy to me:)  Some don't like the fun way of advertising, think it's unprofessional.  To be propaganda it would need to be untrue at the time it was said.  I've not seen anything like that from the company.  Enthusiastic users are just that.  I haven't seen users in these threads talking down other brands, just users of other brands bothered by the enthusiasm for some reason.

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Bill93
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Posted by: Duane Frymire

To be propaganda it would need to be untrue at the time it was said. 

Propaganda doesn't have to be untrue.  I'm not weighing in on whether the subject matter here is propaganda, but just to keep the logic clear.

"Propaganda is information that is not objective and is used primarily to influence an audience and further an agenda, often by presenting facts selectively to encourage a particular synthesis or perception, or using loaded language to produce an emotional rather than a rational response to the information that is presented."

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Duane Frymire
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In other words, untrue.  I didn't say it needed to be an outright lie, although that would qualify as well.

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Norman Oklahoma
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"To be propaganda it would need to be untrue..."

Propaganda is biased or misleading, but not necessarily untrue.

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Duane Frymire
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I argue propaganda is necessarily untrue.  That is the nature of biased or misleading.  Even splitting hairs like a politician, I haven't noticed anything other than having a little fun with advertising. 

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Norman Oklahoma
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Then you are arguing with the dictionary. Good luck with that. 

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Duane Frymire
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Well it's just interesting to see the Tribal reaction to the newcomer in the context of surveying equipment.  I mean, all kinds of praise for equipment by users on here over the years.  But haven't seen this kind of reaction to any other brands being praised.  I try to ignore but the attempt to marginalize a user's story with claims of propaganda had to be responded to.  I don't think it's fair; you do.  We've both had our say now so I'll drop it.

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Randy Hambright
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Wow, this went from a pat on the back for Javad (which I also own) to a dog pile on the guy for his billing practices. Reminds me of another board from long ago!

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Andy J
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not really... I asked a question and he answered it.   The other discussion was about other people's biz practices, not the OP. 

 

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