Heath Carmody
Inferior Mirage - Symphony of Obstruction.
updated
There have been some questions floating around about inferior mirage such as: "Is an inferior mirage a vertical image or does it occupy the surface plane?" and "Does an inferior mirage obstruct the 'real' object" and "Can an inferior mirage obstruct more information than its own angular size" and "Why does the 'fold line' continue to rise with distance?" This video doesn't directly answer any of these questions, but it attempts to lay the foundation for a more productive discussion and more detailed demonstrations in the near future. You may be able to answer some of those questions yourself after watching, or you may have more questions. Either one is good in the comments. The next video will give my best answer for these four questions, ask a couple more big ones, and try to answer any good ones that come up in discussion.
This video covers the flat plane geometric expectations of the horizon at eye level, and points of equal elevation with eye level appearing in a straight line with perspective. From this baseline we can predict what the image would look like with curving (refracted) light paths, and better understand how apparent obstruction and a closer apparent horizon are both expected effects of upward bending light on a flat plane.
I tried to fit too much into the first 2 videos, since I was eager to get on to the more interesting mirage stuff. I really would like to see everyone on the same page with the basics. This is about as basic as it gets. Probably boring and repetitive for most. That said, since making the first two videos I've added and fixed a few things in my program so that it's a little easier to demonstrate certain things. Hopefully this video will help those who need it and are open to it.
Stretching and compression can also be considered "vertical magnification" and "vertical demagnification" respectively. We could also call these effects "towering" and "stooping", but apparently those terms, along with "sinking" and "looming" are only valid when describing refraction effects on a globe, which we are not.
I have at least 7 more videos planned for this series, most of which are dependent on new features of the program that I'm currently working on in my limited spare time. I'm aiming for each video to be about 5 minutes long. Tentatively, here are the next 7 video ideas.
Part 3 - Inferior Mirage (on a flat plane)
Part 4 - Superior Mirage and Fata Morgana (on a flat plane)
Part 5 - Atmospheric Refraction theory and my program vs. other ray tracers vs. reality
Part 6 - Refraction communication - necessary assumptions, agreeable terminology and causal factors required per model
Part 7 - Refraction effects at multiple distances on a flat plane
Part 8 - Refraction effects on a physical globe
Part 9 - Refraction and mirage on a flat plane vs. a globe - what would be different?
I realize that many of my subscribers are already familiar with the idea of light paths (or "rays") bending or arcing over distance, and how that effects the image we see. Starting with the basics ensures more people will be on the same page when it comes to analyzing mirages. I still have some features to add to the program so that I can demonstrate scenarios involving two objects at different distances.
If you don't understand something presented in this video, please leave a comment and I'll do my best to explain it differently, or clarify points in a future video or livestream. Also, if enough viewers think the concepts could be better explained in a shorter, narrated videos, I'm open to working with someone to make a similar video which would be easier to follow. I know subtitles are hard to read while paying attention to other stuff happening on the screen.
I started adding subtitles to this video to explain some fairly obvious things that I see happening. Then I thought maybe it would be better to not distract from the visuals and see what viewers come up with on their own. What do you see that stands out? What is interesting about the mirage and eye level? What do you notice that supports which (if any) model? If you have a decent understanding of refraction, what changes to the temperature gradient need to happen for this kind of transition to occur? What else do you need to know about the observation to use it as evidence for the model you believe to be correct? None of the things I've noticed require knowing the exact heights of landmarks at the campground, but I can provide more information if anyone wants to get real serious with this. Basically, I just want some points to discuss in a future live stream or narrated video before I give my take on how it supports my long running argument for why the Earth could be flat.
I placed two green lines for the longest segment where the camera didn't move (placed on a large rock). The lower line is my estimated camera "eye level" or horizontal. It's generous in that I think it could be a little lower, but I don't want that to be a huge point of contention. There's a few frames where you can estimate my camera height and compare to close targets yourself, if you doubt my camera line estimate. The second line is simply to mark the top of the highest tree (not quite highest but most visible) as it appears to show how much that height is displaced by the end of the sequence.
I've been on an extended break from Earth shape discussion and YouTube in general, but still managed to get out to the lake a handful of times for some shorter than usual observations. Finally I have a little bit more time to put towards making some new videos and hopefully participating in the discussion again. I haven't totally figured out the approach that I want to take this time, but I'll be experimenting with different styles of videos and maybe some longer narrated videos that actually explain things better than subtitles. This fall I'll also start using my software again for observation analysis, comparison and demonstrations. Who knows, maybe I'll even start live streaming again, if I can get enough people interested in honest observation analysis.
I would like to request that the Flat Earth authoritative context box be inserted underneath this video. I'm hoping that using "Flat Earth" in the title and saying "the Earth is flat" in the description will be enough. I also hope this warrants the inclusion of my video into the 'special category' so that nobody besides a few of my long time subscribers will see it - if all my videos are not already included by default.
Thanks!
I'm well over my data quota for Cesium Ion, so unfortunately I have to work on some videos and other stuff for a while and give this a break. Starting in March I'll be taking requests for which locations/observations to model and see how it matches up with other comparison tools like Peak Finder, or the better one everybody uses that I can never remember the name of.
(youtube.com/@pablosdog2808)
No subtitles since I'm hoping the video will be somewhat self explanatory with these few notes.
The program I'm using is my own software in Unreal Engine 5, with the Cesium plugin enabled. This allows me to import 3D "tiles" for terrain simulation similar to Google Earth. This demo in particular uses Bing maps data and Cesium buildings, but there are other tile sets. I've been fully integrating the Cesium streamed terrain with my existing light curve calculator functionality so that I can do better demonstrations and more accurate analysis of observations. More on this in a full video soon.
The model of platform Henry is using my 2D model of "platform C" scaled up to be the approximate size of Henry. The comparison at the end didn't line up perfectly (horizontally) since I forgot to use the heading for Henry from the old location (where the video screengrab was shot). It makes a small difference, but I will line up a better observation from his new location to see if the headings work for both Henry and the new target, and the peaks in the background. They should. Also, things are out a few pixels from the center point of the screen do to a screen resolution limitation when using Cesium.
To clarify, I'm not asking for exact pixel layout of points to draw the lines, I'm only asking for a general outline of a procedure that would draw the appearance of a curve using only straight line segments (as many as needed to visually appear to be a consistent curve) using the dimensions of the triangle provided. There may be multiple ways to approach it, but I'll explain my way in the next video and address any feedback on this video.
Strong distortion along with strong upward refraction causing downward displacement. But how strong? I don't know yet. Eventually I'll get around to some proper analysis and comparisons between my 'strongest' refraction observations. I also have more footage from this day to present eventually, but unfortunately I only had one camera set up this time.
This video asks the viewer to determine which observation clip best matches the geometric expectations (ignoring refraction for now) of each Earth model, using only a rough eye level reference that I've estimated. It's a simple exercise that may hopefully lead to some discussion about observations over water and what we can actually evidence with them. I'll provide more information and footage from each observation on request, until I get more time to make longer videos about each observation.
I set up my camera looking across about 5 km to the far shore, from a height of about 7-8 inches. This is a continuous time lapse from mid morning to mid afternoon. The camera moved around a few times when I had to reposition the shade umbrella, but the height remained the same throughout.
Very hot day but still typical for the few weeks preceding it. Mornings are generally the best time to capture any sort of convex-ish illusions as a result of upward refraction, in my opinion. The expected strong inferior mirage eventually disappears, revealing near perfect flat geometry for a brief moment, before the concave compression sets in for the rest of the observation. Extreme 'heat distortion' accompanies the 'tiny concave' view. This was one of my better transitions, but still hard to compare and analyze, especially without the ferry in view. For that reason, this video makes no claims and contains no subtitles and no sarcastic globe evidence. Just lightly edited observation footage sped up and 'synced' to loud electronic music.
This observation was a while before my last video (May 17th and June 4th) and from the same height/location, but when the water level was a few meters lower. Now that the lake water level has risen to its annual maximum, there is no beach at any of my observation locations since the water rises right up to the trees in most places. That, the heat and the bugs, makes summer a good time for a little break from observations. I have plenty of video projects to finish up in the mean time.
As for what we are seeing in this observation; brief inferior mirage with very slight obstruction at the mirage 'fold line' at the start, followed by full visibility of the land, and immediately into compression near the bottom, but with strong upward displacement that grows considerably through the end of the time lapse. The next video will go into more detail. The changing water surface effects are the real highlight of this video and something I'll try to capture more often from these higher vantage points.
From the same observation that I've been drawing my 'globe evidence' for my last few videos. I also did this for Observation #10, which I have a similar video that I'll publish in the next few days.
If you want to know more info about this observation location in specific, ask in the comments, or wait for a future video where I do some comparisons vs. the other day (#10), and comparing to the lower camera views. This might not be the best observation for detailed analysis, since I can't estimate my observer height very well, and the angle of view is too wide to get any details on the farther targets, obstruction wise. I also had to splice together 3 separate time lapse segments with different focal lengths, and the camera may have drifted slightly - especially during the final segment, which exaggerates the apparent upward displacement of the base of the close land. Still, I could do a rough estimate of the total displacement of the horizon, which I'm pretty sure was above eye level at the end. I underestimated the last green line horizon position, as technically water is visible higher than that, even if it appears distorted and mirage like. You'll see what I mean.
Tons of long projects still in the works, but I'm trying to get caught up on getting out a couple videos per observation, so I don't forget anything. Still so much to show and talk about, eventually..
I may continue this series after I make a few videos from the other footage from this day, which wasn't as good evidence of a globe, but still needs to be presented, to show I'm not biased.
When there's an inferior mirage limiting our view of some of the water (only the water), there is also sometimes obstruction at the fold line/assumed horizon-ish area. When the target appears to be far enough away for it to be calculated to be obstructed on a globe, we can safely assume that the obstruction is due to Earth curve. I mean, what else could it be? Upward refraction on a flat plane? Impossible. Upward refraction cannot obstruct things that are already behind Earth curve, unless they are obstructed more than they should be.
I've captured similar effects a few times, but never very well. This was no exception. These events catch me off guard because they usually appear first in the areas I'm not watching. They are easily visible to the naked eye at this distance. I've seen similar effects in some of @pablosdog2808 , @theplanetruth and @wideawake2814 's observations as well. I'll link some videos with similar effects in a comment if I get around to it.
I only capture this phenomenon when there is a strong concave appearance to the water surface (appearing elevated above horizontal). The effect is kind of like moving a magnifying glass across an image. The already 'looming' water gets even more displaced upwards, stretched and warped. It sometimes appears to fold back in on itself.
Some might describe this as a distorted superior mirage of the water surface. That may be the case, but I think more likely that the cause of 'classic' superior mirages involves both upward and downward refraction at different distances, and this is likely no different. The extra displacement is possibly due to a relatively cold air mass moving across the deep part of the lake, that dissipates as it mixes with the warmer air closer to land.
Each 'band' represents a slightly different viewing angle to the water. This is evident later in the video when you see how the first dark band is formed by downward displacement (we are seeing that water from a lower angle). I'll be releasing a few more videos from my first 5 similar observations at this location, and I'll explain more about the bands and displacement - the way I've been starting to understand it.
As for the overall strong upward displacement, my measurements are rough with the distortion of the campground, but give a pretty good idea of the geometry involved. If anything, I think my eye level estimate is a little high. Feel free to challenge me on anything if you can tell me how it makes a difference in the flat vs. globe debate. Like if someone said "The looming limit for the globe is 3x the expected drop, so 3.6x could only happen on a flat plane" then I would try to verify my numbers better.
Final notes: This was the hottest day of the week, hottest time of the day, and I went to the super busy boat launch in the early evening to capture this familiar high upward displacement/compression and distorted concave appearance. I also captured similar effects the first 4 observations here this year, and dozens of observations in the past years.
I've decided to do a series of very short videos highlighting my best evidence for obstruction caused by Earth curve. If you don't agree that this observation is strong evidence of obstruction behind a horizon caused by Earth curve, then please share an alternate explanation that does not involve perspective, angular resolution limit, or reflections off water. Also, do not claim "upward refraction", because that can only form inferior mirages if the Earth is a globe.
That said, I'll consider any constructive input on how to make this stronger globe evidence. Do you need to know how far the boat was? How high my camera was? How warm the air was? How warm the water was? How humid the air was? How far to the point on the left? How far to the shoreline behind that? I'll gladly provide my best estimates for anything I can, provided that you can tell me how that information will help make this obvious globe Earth evidence even stronger. Maybe even.. proof?
This is one of the more common refraction scenarios that doesn't seem to change much over a long period of time. I'm always disappointed when I see this condition right of the hop, because it means I've missed the transition from inferior mirage, and missed any potential obstruction. Mirage effects are seldom observed once that apparent 'horizon' has set itself up well above eye level.
In this case, I noticed at one point during the observation that the lowest camera was seeing inferior mirage well before 1 km, obstruction and no water past the mirage, while the slightly higher camera was seeing water all the way to the 5 km point and raised higher than it should appear if flat. Normally, when there is consistent inferior mirage, raising the camera just pushes the mirage starting distance farther away, and no water surface can be seen past the mirage. With multiple gradients doing different things from the surface up, we can sometimes see water 'above' (past) the local inferior mirage. The close gradient is acting as a lens, distorting (by bending light upward) the farther image that has been formed by different conditions (likely some bending downward).
I've shown this effect in many of my past videos, and it's the premise of "See Monster" - how complex inferior mirages are formed (not superior mirages). That will require more explanation, which I'm working on, but this is a good introduction of a close gradient bending light up - independent of how the rest of the distance is affecting light.
Sorry for the noisy background audio. I had to set up next to the gushing stream in order to see the far ferry dock. The camera scraping sounds are annoying and loud too. I tried to clean it up a bit with some filters and EQ.
This is shot with my new camcorder which I've already managed to wreck somehow. Now, after recording for an unknown amount of time, it will randomly stop focusing when I zoom. I mean it doesn't even try to focus, it just gives up and I have to cycle the camcorder off and on to get it to work again for another random interval of time. I think I left it out in the sun too long on the observation before this. Oh well..
This was in the middle of almost 3 weeks of extreme heat (for this time of year here). Data from a somewhat nearby hydrometric monitoring station indicates a high of 26.2°C for this day (May 13th), but my thermometers reached 30°C in the shade on the beach and close to that higher up in the trees. The lake is likely very cold in general and being rapidly fed by cold water from the mountain snowpack. The water temperature at the beach is surprisingly warm though. More on that later. One more hot day to go tomorrow and then it's supposed to cool down and rain a little, more typical of May weather. I'll try for one more hot day observation tomorrow.
The inferior mirage disappears gradually revealing more land and water, while the rest of the image remains virtually unchanged over the course. Except for the background blurring near the end, which might have been a focus thing. This is probably when the complicated mirage effects would have started, since the local lakes are a mixing bowl of vastly different temperature water right now. That combined with the extreme spring heat we've had lately should make for some very dynamic refraction effects after the initial inferior mirage phase.
This is shot at a fairly wide angle compared to most of my time lapse, so while the refraction effects may seem subtle, it's still a fairly big/strong inferior mirage at the start. Camera height wasn't measured but it's in the half meter range. I may research and post the distances of the 3 points of land, if anyone cares that much. Unfortunately, my battery died after just over 2 hours of recording, even though it was charging while recording. Being in the direct hot sun around midday might have been a factor as well.
No claims, comparisons or subtitles. Easy enough video to make that I don't even care if it only gets 50 views. Thanks for watching!
wateroffice.ec.gc.ca/report/real_time_e.html?stn=08NE104
Need to know anything else about the observation? Just ask!
No claims, no mirage to analyze, just a whole lot of big waves. Something a little different for content on my channel, since I've been pretty focused on the 18.6 km point at the ferry for my recent observations and videos, and that's probably not going to change anytime soon.
Warning! - the "music" seems really loud, especially on my phone, even though I had it lower than most of the tracks in my videos. Are they all too loud? I don't want to reupload it just for that. The loud song only lasts from 1:35 to 3:50 or so. Also, I didn't choose the song, the observation did.
Now I think I know why it never appears concave above a certain height, and rarely appears flat shortly above that height range. I mean, I've been thinking this for years, and showing bits and pieces in my videos, but finally I have the footage I need to put it all together and explain a few very important things, the way I see them. Not in this video though.
This video gives a very rough geometric comparison of each model (using my earlier "less compressed" reference shot, cropped to the actual water level) to the apparent image assuming approximate eye level, but that's not the main point. There's something going on with refraction here but it might not be exactly what you think. I want to know what my subscribers see and who has been thinking the same things I have, especially about refraction gradients. If nobody sees what I see, then I have more explaining to do than I thought. But I expect a few to pick up on it..
I may start doing live streams again, or at least narrating some videos. I'll see.
You might be thinking these have to be superior mirages forming at the top of the cliff. I still don't think so. I will explain/model this at some point to show the alternative to superior mirages.
I've done 11 observations so far this season, so I'm playing catch-up with these short highlight videos as reminders of the conditions of the day. Seriously thinking about doing a weekly live stream again. Would anyone be interested in watching or joining if I do?
From Observation #5, same observation as this video: youtu.be/FnsU_wj57j0
This is pretty much all of the footage from my low (and not very good) camera during this 4.5 hour observation, set to loud electronic music that Bobby Shafto probably won't appreciate. There were significant mirage effects occurring higher in the trees at first, with a regular inferior mirage near the surface, until the transition which started with a "double inferior mirage" for lack of a better description. After that, a short relapse to normal-ish inferior mirage, and then the crazy refraction show starts and keeps on going..
I added some very rough reference lines. I'm not claiming them to be 100% accurate. A more accurate analysis will come later when I time sync the footage from 2 or 3 cameras at different heights. There will be some debate about how I established eye level. It was based roughly on what appears obstructed above the fold line of the initial inferior mirage, even though the part I compared was already starting to 'double up'. Knowing the rough scale of the target (based on a horizontal measurement) and the distance, I'm pretty confident about the 27 meter (globe "drop" at 18.6 km) lines in relation to eye level. With that expected geometric difference between models, moving eye level up or down a bit shouldn't change the overall point of this demonstration.
The point of this demonstration is to see if we can generally classify the mirages appearing in the sequence. Inferior and superior mirage, ignoring the full definitions (for now), could be simply described as a mirrored image appearing either below the 'real' or upright object (inferior) or mirrored above the object (superior). By that definition, technically even on a globe everything in the image (except for the water and the first foot of the shoreline) is above my camera elevation. Therefore almost every mirage seen here 'could' be classified as inferior, whether globe or flat, except for the effects happening on the water or at the very base of the land. These should be superior mirages by that general definition. Of course, it gets more complicated when we introduce the actual 'modelling' of these mirages on either model, beyond the fact that the mirages themselves are often complicated sequences of rapidly changing effects. That's really the point of this video, to highlight the mirage effects over time. Whether or not we can actually learn anything from observations like this is still to be determined.
Also interesting to note that the lower trees seem to 'sink' as we see a higher displacement of the water surface causing massive compression from top and bottom.
The main song is called "Moving On" by Marika Schanz. I thought it was suitable in more than one way.
This is a short highlight from one of 3 cameras that were positioned at various heights for a long duration time lapse, all with close height references in frame the entire time. There is a fair bit of analysis work to do, but I think it will be very useful when presented with actual measured displacement over a 5 hour period and a 3 camera time synced view. I don't know why I didn't do this before. I plan to do this a few more times this year too.
This video highlights a particular 'refraction' effect that I don't really have a name for. Similar effects can occur fairly often on warm afternoons. The water appears extremely concave, like, strong downward refraction on (in?) a concave Earth size sphere concave. Of course, there is considerable compression as only the lowest 5-10 meters appear consistently displaced that much. I'll save the model comparisons for the longer videos though. No subtitles to distract from the real time and some sped up footage. If you want more info on this observation, check out most of my last 10 videos, or ask anything, or wait for the full analysis video that may be a while. Otherwise, just enjoy the effect without over analyzing it. And know that eye level is somewhere around or below the middle between the ring thing and the average 'horizon' appearance.
This effect seems to occur when the apparent horizon is well above eye level and the image seems 'slow' compared to other broad refraction/distortion effects. Wispy bands may start to appear and large vertical displacements can be quite localized. The clarity of the 'actual' water reflection is interesting at this height and distance. The water was very calm this day. Objects can appear in different places on the water surface without a distinguishable mirage effect. I've done a few other videos with this effect which I'll post in the comments soon.
Of course everyone is welcome to give their answers/explanations in the comments.
No claims or model comparisons for this one, since I don't have a good eye level reference from that height. The rough angular scale provided should give you an idea if you want to do your own rough analysis. I'm also working on a longer video or series about the "double inferior mirage" seen in many observations including this one from the lower cameras. It will go into detail about the specifics of this observation, and challenge the classifications of inferior and superior mirages.
I don't know what caused the lateral movement in the first main scene, or what makes it return near the end. The OIS was turned off. The breeze wasn't strong enough to move or gradually pivot the camera sitting on a rough aggregate concrete slab table. But I guess anything is possible. I'm leaning towards refraction on this. Considering the range of displacement on the vertical, I think a little bit of temporary horizontal shifting could occur. This small degree of movement would not be noticeable by eye, especially spread over that long of a duration.
I also don't know what is causing the focus issues. This was auto focused nice and clear, then locked and set in manual focus for the time lapse. If there were some kind of rapidly changing non-physical lens between the camera and the target, that might explain it. I'm open to discussing alternate theories for any perceived "full frame" movement, and I will get it sorted soon.
There's a few other interesting things happening in this time lapse. The distant lake water so calm it's hard to tell reflection from inferior mirage at times, possibly some "gravity waves" on the farthest visible land, and a strange look to the water surface as the sun was departing.
This is a typical "black swan" observation, where the water surface appears concave (rising up with distance) from lower elevations. There is considerable compression, miraging and distortion, but no obstruction. Nothing can be obstructed above eye level, although targets can be compressed and visually obscured beyond recognition.
I've been working on this video off and on since March 19th (Shelter Bay observation #3) and I keep going back to make things more accurate as I confirm heights and remeasure everything. Still, I can't guarantee the accuracy of this analysis. It's a good starting point and I'm confident that everything is close, but I'm also open to any suggestions for getting more accurate results. At some point I'll provide a more detailed look at how I determined the rough heights of everything.
These are the best days for visual effects. Similar to observation #2 and #3 (which I have multiple longer videos still in the works), strong downward refraction conditions made for some very interesting and dynamic refraction/mirage effects. Observations #5-7 (yes, I'm at 7 already this season) were also similar, but each day was unique in its own way.
Observation #4 was a 6 hour day that just didn't stop after the inferior mirage lifted. I time compressed many clips to pull from for this heavily edited video, but still have a ton of good footage from the final couple hours of the observation. The clips in this video are roughly in chronological order, but a few might be out of place, not that it matters really. If requested, I can compile all 'steady' footage from each camera and do one long time lapse, since most of the videos have already been sped up and rendered.
So much to show, analyze and discuss, but I had to get as many observations in on these nice early spring days before the rain and cold returns for a few weeks. Not to mention full time work starts now too.
As much as I love time lapse, sometimes the real-time refraction effects are good enough that they don't need to be sped up to show the dramatic changes.
I picked one 20 minute segment out of over 6 hours of recording on this day, to present raw and without any context, comparison, analysis or music. Hopefully, it is interesting enough on its own. If enough people like this I'll start doing the same for each observation.
This was after after a long period of strong inferior mirage, but a somewhat unique transition where the higher areas seemed to stretch before the entire water surface and land became visible. After this point, refraction went kind of crazy (again) and I captured a ton of good footage from 3 cameras. Even though this was similar effects as my last 2 observations, there is always something unique and interesting about each day, and more to learn (and to try to remember), as long as I can stay long enough to capture it.
Camera had a few issues. There's some strong but gradual vertical drift which I like to blame on the tripod, but since there was no wind whatsoever and very strong local refraction, I'm not so sure. I was away from the camera the entire time too. Why did it move and reset back gradually like that? Either way, it's a poor segment to do any real analysis on, but still worth looking at closer. Also, it had trouble focusing a few times and I realized after that the motion stabilizer was on, not full but on basic. I try to keep it off for tripod recording.
If you want to know anything about this observation please ask or check out my last few videos with some basic info on the location. I will be making more videos of this observation soon. Still working on a long video from observation #3 and more stuff from all 4 days and counting..
I recorded about 3 hours of footage from 3 cameras. This is only the time lapse from the 4K camera. I placed it on a concrete picnic table to ensure there would be no tripod movement from wind, even though there was barely a breeze.
The camera was about 13-15 meters above the lake. I'm still trying to pin down my heights and the exact scale of the 18.5 km point of interest, but this observation is mostly about the dynamic visual effects of refraction, rather than empirical measurements. That water sure does consistently remain visible an awful long way past the point though..
I should note that I measured a considerable temperature inversion from near the surface to the camera location right before the end of this observation, which I'll talk about in the next video because there was an unexpected anomaly. As you can imagine, there were some giant 'black swans' from the lower cameras, where actual eye level is more measurable. I'll be featuring those as soon as this lucky spell of nice sunny early spring weather runs out.
This was a warmer day than my first observation, although still cool for the first few hours and towards the end. Temperature readings showed a moderate inversion from near the water to the high camera location. I also had an even stronger inversion the next day. Details in a future video.
5 or so hours of observing but I had to cut up the footage since I panned around so much. There was a light breeze, stronger higher up. It made for some annoying tripod movement, but it's not my worst footage by far.
Now that it's finally warming up, I'll be doing a true first observation this weekend. I don't know what I will see, but I can guarantee it will be more interesting than this footage.
This is basically just a quick introduction of the location, some highlights and time lapse of a 2.5 hour observation with very 'standard' conditions and a stable inferior mirage. Windy up higher and fairly clear conditions, but still a fair bit of refraction distortion looking over 18 km. Nothing new or exciting and no claims related to Earth shape. Next one though..
Fun fact - the Swanalyzer was developed years ago as a tool to analyze so called "black swan" observations, which is a description generally given to observations with a 'concave' appearance of the surface. It originally could only analyze points of known distance along the surface. I added elevations a while back so that 'non black swan' observations could also be analyzed. However, as this video touches on, there is still room for improvement when it comes to determining accurate ray radius values for the entire height of the image. But let's keep it simple for now..
No claims of Earth shape are made in this video. This is simply a demonstration of localized refraction effects and their effects on more distant targets.
It seems any mention of sphere, curve, radius, and even 'orthographic renderings' can make certain flat Earth proponents weary and defensive. Please know that anything I demonstrate here is in reference to geometry, not reality. We are comparing geometric shapes; a plane vs. a sphere, not a flat Earth vs. a globe Earth. All rules of perspective still apply to any predictions made about how those geometric shapes would appear if viewed through a camera lens at a specific height. My only intention is to demonstrate that there is a geometric difference between a sphere and a flat plane, and that difference can be observed and measured in a model. The same differences can be observed in reality, but they cannot be used to determine the shape of the Earth because of refraction, or some other unknown light path bending factor. A model just gives us an agreeable starting point for reasonable discussion.
The main point is that a spherical appearance cannot be blamed on perspective. Perspective only knows straight lines. Understanding and agreeing when something 'looks curved', is not the same as agreeing that the Earth is a sphere. I do this for my own benefit as well, to review my thoughts and make sure I didn't miss anything.