Lake Balaton Laser experiment to determine the curvature of the Earth, if any.

[Hama Neggs]

Sandor has been attacked here and not respected as a fellow scientist.

Wrong. He was given plenty of leeway to show his experiment. It was flawed. Very, very flawed. As Sandor would say.. argue the data, please. Can you?

 

[Mick West]

The issue here is claims of evidence. Sandor was given repeated opportunities to address the problems that were found - particularly the "direct hit" problem. He did not do so. He then claimed that a study supported his finding when it did not.

His claims have been examined in great depth, and they have been shown to be incorrect. Rebuttals were encouraged, but were not forthcoming.

 

[Rory]

Good because the feeling I get from reading the comments here, is that noway nohow is the earth not round so therefor we will pull our hairs out looking for the fault in the data. Hopefully that attitude will result in better testing procedures and not another round of "there must be fault somewhere, because we can't accept your conclusion" type of discussion.

I think one of the big problems for Sandor and his team is that they don't seem to understand what a real scientific experiment involves. You've got to admit, it was a bit of a Keystone Cops show, with bits of sticky tape, guys holding tape measures over water, slanted boards, taking readings off the backs of people's jackets.

All I know about experiments is based on university labs and reading. Real science looks mindnumbingly boring. Endlessly repetitive. Checking and double-checking and checking again.

I thought reading about the Arago and Biot mission to plot the meridian line was instructive: it took them years and they'd take readings day after day after day, calculated to super-accurate degrees, being very, very careful to understand and accommodate the effects of refraction.

It's not just a one shot thing. If he's serious about this he needs to be camped at the lake for a month, meticulously observing. One doesn't just send out one boat, come back with inconclusive data, and then decide two and a half thousand years of scientific understanding has been overturned.

Really, I don't see what the big problem is. He has a lake, he has a boat, he has equipment. Send the boat out over the horizon and work out why he can't see it. Do the Wallace experiment. Do them again and again and again, over the course of a week, if he has to.

At least something like that would be approaching what a real experiment would look like.

 

[deirdre]

He has spoken personally to them and posted what they said. You doubted his honesty so decided to contact them yourself. He never spoke to the individual you emailed and never stated such. That was just your assumption and is disingenuous.

Then give a name. Or are you looking to get banned for libeling the scientists of the paper?
because here he is saying that he did not speak to them at all.

we are not signing an NDA, but a cooperation agreement that needs director approval. Not with the persons or institutes listed in the LIDAR pdf - please don't take guesses here. Until that approval I am NOT suposed to tell the names of the participants (person or institute)

Sandor has been attacked here and not respected as a fellow scientist.

Sandor is a scientist? since when? And the only sicentist i know on this thread is Auldy. are other posters here scientists?

Yes it seems a common style of debate when one side can't accept the other sides conclusion as possible. That to me is not a open fair scientific debate that has the goal of getting to the truth.

Steve, even I know this experiment is not good and does not show what Sandors claims it shows. Are you saying that asking questions is not fair in a scientific debate? I do not understand this concept.

 

[mm1145]

No, the entire point of this site is to look at claims of evidence.

And I'd actually really like to see this test done well.

I semi-seriousley considered if I could redo it I have a boat on lake coniston and it is 8.8km long but I do not have a laser and I do nto know how you might so somthign simular.

I wandered if you could mark the mast of the boat and use somthign like a thoidlate to take meserments?

 

[Bruno D.]

Yes it seems a common style of debate when one side can't accept the other sides conclusion as possible. That to me is not a open fair scientific debate that has the goal of getting to the truth.

Steve, there are no conclusions to be accepted.

All the measures after C5 are not accurate. The experiment doesn't prove a Flat Earth and it doesn't prove a Globe Earth.

I really would like the experiment to be reviewed and re-executed, because the data Sandor has right now is not conclusive, at all, and is being used as definitive proof, what is completely dishonest. The next experiment is going to be treated with even more skepticism because Sandor and his team are using the current flawed experiment data instead of acknowledging that it's not enough and he needs to redo it.

Of course some of the people here got emotional and attacked the person, not the experiment, but this is an open public forum after all. On the other hand, more than half of the people pointed out flaws and what needs to be done to enhance the experiment, and all those criticisms were responded with bluntness and abruptness by you and Sandor.

If a new experiment is done the correct way (bigger board, more measurements, beam dispersion taken into account, documented process, etc), and it still shows a line, and not a curve, I can assure you that many people here will be very intrigued and willing to explore the reasons. Heck, I believe many real scientists will love to understand what's happening there.

Not with the current data and attitude though.

 

[Bernard Mc Donnell]

I see they're looking at his "NUDTZ" over there currently. This is a great example of skewing data and misrepresenting the results. We've talked about this term here, and I'd say it's going to get a good rollocking, because in science you don't just make up facts on the spot.

You present hypothesis, test it, look back over the hypothesis, test it some more, look back, test, etc. Eventually the hypothesis will have been tested to death and then when no fault can be found begins the peer review. If it passes that you may even be able to name new phenomena that peer review couldn't find fault with. All of a sudden you have something quite possibly resembling a scientific theory, which explains all the facts perfectly.

 

[Mick West]

I see Sandor has been banned. I also see that he has attempted to start the debate in another forum, http://www.scienceforums.net/topic/98386-laser-curvature-test-on-lake-balaton/

Someone should really add a link back to the OP here, which has the summary of the problems. They are just retracing old arguments there.

 

[Bernard Mc Donnell]

Someone should really add a link back to the OP here, which has the summary of the problems. They are just retracing old arguments there.

One of their moderators has asked to keep the two separate. That said they probably would appreciate the opportunity to browseover this thread. They've already pointed out a few of the same problems.

 

[Robert S]

I'm only on page 14 but I'll put perfectly good American pesos on the line and say the "direct hits" shown in photos from shore are the laser beam illuminating the patch of retroreflector placed on the back of sailing gear to make SAR easier. (I'll post an example of said patchs on a jacket later) If this is the case all the photos from shore show is the height of the patch above water.

 

[Mick West]

I'm only on page 14 but I'll put perfectly good American pesos on the line and say the "direct hits" shown in photos from shore are the laser beam illuminating the patch of retroreflector placed on the back of sailing gear to make SAR easier. (I'll post an example of said patchs on a jacket later) If this is the case all the photos from shore show is the height of the patch above water.

Page 18
https://www.metabunk.org/lake-balat...of-the-earth-if-any.t7780/page-18#post-190576

 

[Spectrar Ghost]

I'm only on page 14 but I'll put perfectly good American pesos on the line and say the "direct hits" shown in photos from shore are the laser beam illuminating the patch of retroreflector placed on the back of sailing gear to make SAR easier. (I'll post an example of said patchs on a jacket later) If this is the case all the photos from shore show is the height of the patch above water.

Some are. Some are just seeing the laser origin in the camera.

 

[Robert S]

Page 18
https://www.metabunk.org/lake-balat...of-the-earth-if-any.t7780/page-18#post-190576

Well crud, someone noticed it before I posted With the screencap showing the back of the jacket at least I don't need to go digging foul weather gear out of the closet.

You can see that glints from lenses and shiny surfaces are much less visible than the retroreflective patch so all the effort does have one useful result. (having a surveyor designate a target across the lake in line with local level where the laser is and just pointing the laser so it hits the target would be the easiest "leveling" method in case it ever comes up again)

 

[skephu]

Sandor was banned for a cumulation of violations of the posting guidelines, ending with his blatant misrepresentation of this paper, typified by the following post

But that is probably a simple misunderstanding on his part.
You know Hanlon's razor, do you?

 

[Landru]

But that is probably a simple misunderstanding on his part.
You know Hanlon's razor, do you?

Mick didn't say lie he said blatant misrepresentation which it clearly was. He claimed he had spoken on the phone with them in Hungarian and the said the LIDAR data showed flat (as in not round) surface. That's pretty blatant.

 

[skephu]

He claimed he had spoken on the phone with them in Hungarian and the said the LIDAR data showed flat (as in not rouns) surface. That's pretty blatant.

It can still be a misunderstanding. Flat can mean flat like a plain is flat. Even in English:

flat

1. having a level surface, not curved or sloping
2. (of land) without any slopes or hills
   • The road stretched ahead across the flat landscape.
   • The desert was flat, mile after mile.
   • He reached a flatter section of land near the river.

Wikipedia: Flat (landform)

A flat is a relatively level surface of land within a region of greater relief, such as hills or mountains, usually used in the plural.[1] The term is often used to name places with such features, for example, Yucca Flat or Henninger Flats. Flat is also used to describe other level geographic areas as mud flats or tidal flats.

Similar in Hungarian. They could have said the water is flat, meaning flat like a plain is flat.

plain (also plains [plural])
a large area of flat land

• the flat coastal plain of Thassos
• the Great Plains

Flat in geography has a different meaning than flat in geometry. This can easily lead to misunderstandings, probably in most languages.

 

[Landru]

It can still be a misunderstanding. Flat can mean flat like a plain is flat. Even in English:

flat

1. having a level surface, not curved or sloping
2. (of land) without any slopes or hills
   • The road stretched ahead across the flat landscape.
   • The desert was flat, mile after mile.
   • He reached a flatter section of land near the river.

Wikipedia: Flat (landform)

A flat is a relatively level surface of land within a region of greater relief, such as hills or mountains, usually used in the plural.[1] The term is often used to name places with such features, for example, Yucca Flat or Henninger Flats. Flat is also used to describe other level geographic areas as mud flats or tidal flats.

Similar in Hungarian. They could have said the water is flat, meaning flat like a plain is flat.

plain (also plains [plural])
a large area of flat land

• the flat coastal plain of Thassos
• the Great Plains

Flat in geography has a different meaning than flat in geometry. This can easily lead to misunderstandings, probably in most languages.

Sandor did a whole thing about how, in Hungarian, he parsed the different Hungarian meaning of flat and level. He was blatantly misleading.

 

[skephu]

He was blatantly misleading.

He still may have acted in good faith. You are assuming malice.
Also, I don't think it is wise to ban him; you guys only make him a hero in the FE communities.

 

[Landru]

He still may have acted in good faith. You are assuming malice.
Also, I don't think it is wise to ban him; you guys only make him a hero in the FE communities.

It was Mick's decision but one I support. It was for many PG violations. His new forum is even stricter than us.

 

[Akantor]

He still may have acted in good faith. You are assuming malice.
Also, I don't think it is wise to ban him; you guys only make him a hero in the FE communities.

How did we make him a hero in their community?

 

[Hama Neggs]

His thread on the other forum seems to have gone pretty quiet.

 

[snaphat]

He still may have acted in good faith. You are assuming malice.
Also, I don't think it is wise to ban him; you guys only make him a hero in the FE communities.

If he had been acting in good faith, he wouldn't have been ignoring critical questions about his methodology or trying to misrepresent other work as in agreement to his. The levelness thing had been explained to him several times prior in this thread. It's actually a super common argument flat earth believers will make. In the past, I've actually discussed with a few who made the same claim for the term 'equipotential level' in the very paper that defines the WGS84 reference ellipsoid used in GPS. They also similarly refused to believe the term meant anything but flat.

I also have had a bit of experience with Sandor himself on FB threads before he did his experiment here and that's actually how I found out he was going to post the details here. To keep it short, he exhibited similar behavior to what he was doing here at the last end, but was much more rude in how went about dismissing discussion and criticism. The thing is, because this is metabunk and moderated, this thread was very useful in keeping the topic focused on the experiment and criticism of the experiment and not allowing this to divulge into a rabbit hole of deflection, red herrings, and other such irrelevant things. Mick and the moderators do a really good job here and their decision seems like the right one to me.

 

[Bernard Mc Donnell]

If he had been acting in good faith, he wouldn't have been ignoring critical questions about his methodology or trying to misrepresent other work as in agreement to his. The levelness thing had been explained to him several times prior in this thread. It's actually a super common argument flat earth believers will make. In the past, I've actually discussed with a few who made the same claim for the term 'equipotential level' in the very paper that defines the WGS84 reference ellipsoid used in GPS. They also similarly refused to believe the term meant anything but flat.

I also have had a bit of experience with Sandor himself on FB threads before he did his experiment here and that's actually how I found out he was going to post the details here. To keep it short, he exhibited similar behavior to what he was doing here at the last end, but was much more rude in how went about dismissing discussion and criticism. The thing is, because this is metabunk and moderated, this thread was very useful in keeping the topic focused on the experiment and criticism of the experiment and not allowing this to divulge into a rabbit hole of deflection, red herrings, and other such irrelevant things. Mick and the moderators do a really good job here and their decision seems like the right one to me.

Yes I've observed you in a couple of the Facebook groups and on YouTube, you did seem to do a good job at staying level headed and sticking to the points, which unfortunately, as seen here, leads to dismissive replies, or deflection. I saw you got kicked from one purely for giving your critique on this very experiment. You made some excellent points, some of which were also made here.

 

[deirdre]

or trying to misrepresent other work as in agreement to his

I do believe he does not understand the other work. I think he really does believe it agrees with his conclusions.

To me, I agree that Mick's ban was appropriate (aside from multiple previous PG violations) because he was paraphrasing a "specific person" ie the authors of the paper he claimed , without naming the person and giving the person a chance to respond and correct his misrepresentation. So, in effect he was misrepresenting and tarnishing the reputations of ALL authors of the paper. That's not cool.

I also have had a bit of experience with Sandor himself on FB threads

But i dont think a lengthy discussion and repeated explanations are necessary. People can read the thread and see for themselves how he responds to questions and conflicting evidence. I dont think someone's behavior on FB is relevant, as that is a completely different type forum.

 

[DougW]

How about because he steadfastly avoided answering direct questions about his experiment and refused to acknowledge data gleaned from his own video which demonstrated problems with his experiment? Why let him continue with that?

I think Mick's reasoning for his ban was warranted and correct and the answer I was looking for! - it's one thing to not answer or avoid questions (which he had been doing for the last couple of weeks without any real warning) but to misrepresent another study/paper sealed it for himself. Personally after he started releasing his data and pictures etc and he started becoming aggressive in his tone and response (which surprised me considering his 'open attitude' before he collected his data) - that for me was the end of this thread.

 

[DarkStar]

Viral? It has 26 views.

Can I get an autograph?

Really you should just do a Wallace experiment. That would settle it.

At least 10m over the water please.

This validates the 118.5cm measurement, and hence is more evidence the laser was pointing downwards.

1m board length = 452 pixels
So you have 452 pixels/meter
Total vertical height to the top of tape marked (1.3m) = 536 pixels

Dimensional analysis:

So you have 536 pixels / 452 pixels/meter = ~1.186m

That checks out.

Margin of error check:

540 pixels / 450 pixels/meter = 1.2m
540 pixels / 452 pixels/meter = 1.195m

At least 10cm off even if you are a few pixels off.

Cross checking with your angular estimate of error:

Adjusting for the horizon, that's 24° of slope. Cos(24) = 0.91, so about 9% error.

This agrees with the pixel estimate.

At these points in their video:


Source: https://youtu.be/GBhDFO4NMrw?t=835


Source: https://youtu.be/GBhDFO4NMrw?t=862


you can clearly see they are putting the tape against the slanted board to measure height - this confirms that this slanted measurement method was used at those points.

I couldn't find where the 1.3m tape mark was made - that would be useful info to confirm.

But from the info we have it looks like a significant measurement error.

 

[DarkStar]

we will soon get to the point now, how 465 meters of curvature is impossible on the 77kms distance of the lake.

If it DIDN'T curve something close to that then one end of the lake would be about 465 meters higher elevation than the other end. It isn't, so it does curve over the 77 kms.


Also, an astute reader pointed me to another thread on this topic people might find interesting.

http://www.scienceforums.net/topic/98386-laser-curvature-test-on-lake-balaton
(someone already posted that, sorry)

 

[DarkStar]

Yes it seems a common style of debate when one side can't accept the other sides conclusion as possible.

Like when Sandor refuses to acknowledged the obviously large beam divergence (even after Mick showed this VERY clearly with the short video of the width of the reflection)? Or that it is hitting a reflector on the jacket causing a false positive? Or that 'camera hits' aren't reliable either (and is shown numerous examples of why)? Or when shown that the height of the mark is plainly wrong AFTER saying:

On the photos you can tell the height of the laser by calculating the number of pixels above the board and comparing them with the board size. If you use a high resolution photoshop you can calculate quite precisely.

Sandor was not able to present his case in good faith, I don't think he was malicious but had too much invested to be wrong.

On the topic of Mick contacting the author of the paper, Sandor had written:

WELL I did read the WHOLE article and it states that the water surface is level straight.
I will talk to them and get all final docs.

So he at least claimed to be in contact with the authors of that specific ('lidar') paper.

If you have a dispute with the evidence, Sandor is more than willing to answer any questions as he has been doing.

Not an accurate statement - he repeatedly ignored very valid questions and when he did respond he just offered assertions "no refraction!", "can't be wrong measurement", etc and didn't really work to get to the meat of the issue.

And instead of acknowledging the issues and trying again they publish their video as "Laser Test Proves The Flat Earth".

Not even close. Even if you PROVED the lake was 100% flat it doesn't prove the Earth is flat and you have experts in the field telling you it is curved.

 

[Miss VocalCord]

I've been lurching on this topic, and also seen it on the 'other' forum. I couldn't find it back in the thread anymore, but did they explain how they measured the height when the laser wasn't hitting the board?
I only saw talking about 'direct hit' but how did they measure the height of it?

 

[snaphat]

I was looking at the data Sandor provided again because I was curious about the patterns in the data I mentioned earlier in the thread. I decided to plot the change in measured beam height from point to point for both the results he obtained and the flat earth nominal change. I found the results to be interesting to say the least.

• dRes is the change in Sandor's measured values from point to point.
• dNom is the change in "measured" values using his nominal flat earth calculation.
• dNom - dRes is the difference between the two.
• Coalesced - to be explained below.

If you take a look (at dNom-dRes), it appears that much of the time Sandor's results (for the change in height between points) deviate by 0.00 or 0.01 from nominal. This means they slowly diverge by 0.01 per point in general. At other points, they appear to deviate by more (marked in blue) but then subsequent data points appear to compensate for the discrepancy from the nominal values. Or to explain that differently, the red points in dRes add up to the same value as the green points in dNom. So, if you then treat these discrepancies as a single point (by adding them together) as shown in the Coalesced column (in yellow), what you get is is a deviation of only 0.01 maximum at any point. This would explain the patterns in the data (in the chart I showed a number of posts ago), as if someone were trying to consistently under compensate by 0.00 or 0.01 but wanted to spread it over multiple points to make it less obvious. That sort of thing would necessarily result in patterns in the data.

Let me know what you guys think (or if I didn't explain this clearly).

 

[Bernard Mc Donnell]

@DarkStar, you pointed out something very interesting in your last post. Showing yet more contradictions, and twisting of words when it suits/doesn't suit his methods.

On the photos you can tell the height of the laser by calculating the number of pixels above the board and comparing them with the board size. If you use a high resolution photoshop you can calculate quite precisely.

After this, @Mick West did exactly that. And then he was met with:

and now you think they measured the board wrong because you analyses it in photoshop? This doesn't seem like a serious debate aimed at coming to a conclusion

and this:

what does it tell you? photoshop is not a measurement tool. your hypothesis of laser pointing downwards does not match the measdured data:

and this again:

photoshop is not so accurate to measure a moving boat with bending to the side and perspective distorsion playing a role in the Canon camera.

I wonder if Mick had actually confirmed their leveling measurements were correct would they lauded Sandor's claim about Photoshop as some sort of "be all, end all". Sandor, and @Steve Torrence (someone who wasn't involved in the actual experiment and stated that he couldn't answer specific questions, except about his evaluation, he sure does seem to think he knows enough to criticize people who have given Sandor every chance to produce and improve something valid, not just for us, but for everyone), have been quite sneaky in their tactics here. Constantly liking each others posts, and disliking valid points (which is their prerogative I guess), purely because these points didn't say "yes!! You did it, I can't believe you did it!! Cue paradigm shift, and sign me up to flat earth!"

This video and the data taken does not amount to a proof, or even scientific paper. Sandor and Steve should actually be embarrassed by their behaviour here! It's clear that the only requirement from the start was, do it right. Why didn't you?

 

[Bernard Mc Donnell]

I was looking at the data Sandor provided again because I was curious about the patterns in the data I mentioned earlier in the thread. I decided to plot the change in measured beam height from point to point for both the results he obtained and the flat earth nominal change. I found the results to be interesting to say the least.

• dRes is the change in Sandor's measured values from point to point.
• dNom is the change in "measured" values using his nominal flat earth calculation.
• dNom - dRes is the difference between the two.
• Coalesced - to be explained below.

If you take a look (at dNom-dRes), it appears that much of the time Sandor's results (for the change in height between points) deviate by 0.00 or 0.01 from nominal. This means they slowly diverge by 0.01 per point in general. At other points, they appear to deviate by more (marked in blue) but then subsequent data points appear to compensate for the discrepancy from the nominal values. Or to explain that differently, the red points in dRes add up to the same value as the green points in dNom. So, if you then treat these discrepancies as a single point (by adding them together) as shown in the Coalesced column (in yellow), what you get is is a deviation of only 0.01 maximum at any point. This would explain the patterns in the data (in the chart I showed a number of posts ago), as if someone were trying to consistently under compensate by 0.00 or 0.01 but wanted to spread it over multiple points to make it less obvious. That sort of thing would necessarily result in patterns in the data.

Let me know what you guys think (or if I didn't explain this clearly).

View attachment 21359

I think I catch your meaning, but I'll have to reread a couple of times later to catch full understanding of the figures. Interesting thought.

 

[deirdre]

I only saw talking about 'direct hit' but how did they measure the height of it?

they said something along the lines of (paraphrased) 'Nick is 6 feet tall so the camera at eye level would have been x feet' . in one night shot (which that experiment isnt discussed in the video) someone held their hand up and there was light on the hand, so i guess they again figured 'man with light on hand is x feet tall and so with his arm raised the hit would be about x feet high.

 

[Miss VocalCord]

they said something along the lines of (paraphrased) 'Nick is 6 feet tall so the camera at eye level would have been x feet' . in one night shot (which that experiment isnt discussed in the video) someone held their hand up and there was light on the hand, so i guess they again figured 'man with light on hand is x feet tall and so with his arm raised the hit would be about x feet high.

Ah, I see. The reason I was asking is that they claim rather precise measurements, even when the laser wasn't hitting the white board (which I think stopped at 135cm).
E.g. C13 = 1.59cm , C14 = 1.60cm, C15=1.61cm
it really looks like 'made up' data to me then.

 

[deirdre]

it really looks like 'made up' data to me then.

i got the impression that they really believed if they saw any light that meant it was a direct hit. but as has been shown, the beam was really a cone and what they were considering direct hits was really the bottom edge of the cone of light.

but even as far as the bottom edge of cone they thought they were seeing, there was no real measurement. With a tape measure or anything.

 

[snaphat]

Ah, I see. The reason I was asking is that they claim rather precise measurements, even when the laser wasn't hitting the white board (which I think stopped at 135cm).
E.g. C13 = 1.59cm , C14 = 1.60cm, C15=1.61cm
it really looks like 'made up' data to me then.

Based off of the unexpected behavior seen in the results as I indicated above, I think it's safe to say they are suspect.

 

[NoParty]

@DarkStar...more contradictions, and twisting of words...

Great post, Mc Donnell.

I think these two excerpts, alone, sum up the Sisyphean task of trying to discuss
something with someone who is seemingly more dedicated to promoting an ideology
than getting at the truth.

Sandor Szekely said: ↑
"...If you use a high resolution photoshop you can calculate quite precisely."

Sandor Szekely said: ↑
"...photoshop is not a measurement tool."

 

[DarkStar]

as if someone were trying to consistently under compensate by 0.00 or 0.01 but wanted to spread it over multiple points to make it less obvious. That sort of thing would necessarily result in patterns in the data.

Meh, I prefer to think they let their bias unconsciously guide their 'eyeballing estimates' rather than purposefully faking the data.

I think Mick identified the major methodological flaws pretty well, I think they suffice to consider this a bust.

A quick summary/review:

1) measuring height along the slanted board, likely resulting in ~9% error in 'slope corrected leveling' method [link1, link2] - confirmed by observing measuring methodology used for other heights and also by photo analysis. This likely resulted in a slight initial downward slope on the laser.
2) laser beam divergence is clearly much greater than they are admitting, creating false hits (shown in #3 & #5)
3) reflective patch on back of jacket and glints off camera lens giving false 'hits' [link1, link2]
4) 'direct hit in camera' is also demonstrated as not reliable (combined with #2 & #3) [link]
5) evidence that the laser is initially pointed slightly down (data at C5 & C8) [link]

I hope that Sandor and team will take the issues seriously and simply try again with the knowledge gained in the process.

It might be interesting to try and take the series of photos between C4 and C8 and maybe one or two past that and see how things line up using Mick's estimates of beam spread and ACTUAL height of the marks on the board and slight initial downward angle?

 

[deirdre]

2) laser beam divergence

one thing i'd like to point out as a layman. i thought 'divergence' means the entire cone of light.
But then it was pointed out to me that 'divergence' is really just the whitish bright spot in the middle and the outer green light is 'atmospheric refraction'.
i don't personally want to call it refraction because the area above the water is also 'refraction' so i think it makes the terms confusing.. so i'm going to call it 'spread'.

So i think one bit of conversation with Sandor (in my case) might have been that i was saying divergence to mean the whole cone and maybe he was thinking i was just talking about the bright spot in the middle?

so i'm wondering if your sentence there should be changed to "divergence and spread" ??

 

[Hama Neggs]

By the height of the guy holding the camera.

Ah, I see. The reason I was asking is that they claim rather precise measurements, even when the laser wasn't hitting the white board (which I think stopped at 135cm).

This was pointed out numerous times with screen shot examples included. It was steadfastly ignored.