I appreciate the long videos, which combine the different methods together in one video. This simplifies matters considerably by enabling the viewer to group the different techniques that are all related. It helps deduce the diversity of chartwork studies, by refreshing/teaching the various techniques together. Thank you for all your teaching either way!
All your videos are extremely useful - short or long - they are well narrated, the animation is great and the information is clear and concise - well done! I have been dancing around celestial navigation for years but the time has come and I will soon buy a sextant. I will be using your videos to get started with it. Thank you!
I'm in ...ahem...the same boat. I'm taking a basic nav/chartwork course starting next month and am going to be using Casual Animation's videos as an addition.
These videos are fantastic. I like the long format but whatever works for you is perfectly fine. I would love to hear about the use of precision for all of these approaches. Ideally precision would include human factors and a way to characterize the precision in various environments. With this our fixes could have a proper cocked hat or more likely a circle of probable location.
You have made this discombobulating subject become something earthly! Personally i think you are one of the very best teachers in this subject, your work on the Sextant was fabulous, and understandable, however, I perfer the long winded, obvious, and easy to grasp stuff, It needs to be tactile, hammered in and tangible for me, so I thank you all for your patience, but keep on with the videos, I find them very informative, and as a decendant of excellent navigators, you give me hope of understanding the details, perhaps you could tell me how you find the stars?! What where and how, how come, you would know etc!!!/
The deviation card is for the steering compass and is found by "swinging the compass", turning the boat through the points of the compass and noting the deviation. A handbearing compass will have a deviation depending on where you are in the boat and it cannot be corrected for as in the video - the position line shown at 5;55 could be 4 degrees in error. Either a neutral location is found in the boat (by experimentation), or several bearings made from different places in the boat.
@@mariusstan7258 The sailor took a hand-held compass bearing to the lighthouse and applied the steering compass deviation to it. They are two different compasses and the deviation does not apply to both equally.
This is by far the best video Yes less is best to answer your questions Yes... Far less is best.. less info per video. So my Sea scouts can go back to just the video they need to review. Also please be sure to TELL us first what your going to tells us NEW in the first 10 seconds, sentence and paragraph. Then show us then remind us. Be sure to show it to us mutiple times in a row slowly. Then tell us what you told us at the end faster ... Last but most important... always review old info multiple times while adding new info, words and techniques. All NEW things need to be said and shown multiple times before they sink into the brain These are just the basic S.O.P. of teaching today as you know. Great Job
Longer the better. Easier to review. If one video contains the full range of data, but you need to refer to two or more segments of the presentation in order to clear up a mis-understood concept, you can always open multiple copies of the video and "navigate" to the several sections needed to achieve understanding. Not unlike fixing your location using different techniques. IF the videos are long, however, it is necessary to divide them up into chapters that will permit easier seek and find. I really wish I had had UA-cam when I was 12 ! ! !
Error in your application of compass deviation. 60 degrees compass bearing does not give a deviation of 4 degrees West. The deviation card has compass bearing of 45 degrees resulting in 2 degrees W, and 90 degrees has 0 degrees deviation . I would therefore use 1 degree West as the deviation correction in the example shown.
That's a tough question to answer. I think both long and short are great. Depends on the complexity of the subject I suppose. Consider all of your audience as noobs or armchair sailors, and do your videos accordingly. They are very, very well done!
The length of video here didn’t bother me , the content is the importance in which case I enjoyed the information from start to finish , great job , liked and subscribed👍
All the clips are fantastic. long or short! I have been attending courses back and forth all over the UK for the last 8 months and I always come back here for reference....you couldn't come and do my Masters Oral Exam in Belfast on Friday could you???
The GPS does not have "several LOPs hidden away"!! The position it calculates is the apex of several triangles, pyramids, if you like, coming down from the GPS satellites whose distance it calculated. The apex moves around a little as the calculations are performed, giving the horizontal (and larger vertical) errors of position.
Fixing position is important to the navigator a fix is a term is used in "position fixing" in navigation fixes are necessary part of navigation by dead reckoning because dead reckoning relies on estimates of speed course. The fix confirms the actual position during a voyage. As a freshman this will be a challenging and exciting topic to meet, I expect to learn more about this topic this topic.
Questions: 1. If you took a visual bearing of a celestial body and made a note of the time UTC you could calculate the azimuth of the celestial body using LHA, DR Lat and Dec. From the value obtained you could calculate the difference between the visual bearing (compass) and the azimuth (true) which would give you a Total Correction. With this Total Correction you could convert from a Compass Bearing to a True Bearing, and viceversa. Is that correct? 2. Regarding the range, could we use the water depths shown on the nautical chart as a second point / line of position to determine how far we are from the lighthouse if we used a handheld or ship's depth sounder? Thank you for this video. I am going through a learning curve, so any feedback will be much appreciated. Cheers.
you can convert those true bearings to compass bearings, and they are to be used to determine compass error at that heading at that time. consider measuring sun azimuths to be a way to swing the compass out of sight of land.
for your second question, you can use a depth as an LOP if you're very confident that it forms a line. look on your chart for very dramatic cliffs of depth.
I don't agree . If you take a compass bearing to a known feature ( the lighthouse ) from an unknown position ( your current location ) then you need to convert the final bearing you calculated to a " back bearing " ( add or subtract 180 degrees ) and place the protractor vertical against the grid line 0-360 to North and the center of the protractor is on the lighthouse and then draw the line from the lighthouse through the correct bearing figure on the protractor . You are then located somewhere along that line of sight . There is a slight convergence between the Grid on the map and True North. It's small at the Equator and gets bigger as the grid lines converge at the poles . If you are measuring aligned to the grid lines your not really using a true bearing . Just measuring on my screen that compass rose seems to be orientated to Grid and Magnetic variation and it's not clear if any Grid Convergence is added into the magnetic variation amount .
on compass deviations table: deviation from 000 to 45 are 4 degrees deviation, from 45 to 090 degrees the deviation is 2 degrees, so the Bearing (M) it is 58 degrees not 56 degrees...
I don't think it's correct, since is decreasing, so it should be 16deg15' minus 6minutes (considering it is only one year after the 2018)...Either way, you can't keep a steady course on the compass regarding minutes, you (or the auto-pilot) can barely hold degrees. So a round 16deg should be acceptable for to be taken in to consideration. BUT the theory behind is important, not the small figures. Also, IMHO, the DEV taken, should have been 1deg W, not 4, because the bearing was 60deg, so in between 45 and 90 (hence, between 2W and 0)
yep your are correct 16 degrees 15 minutes = 16 degrees and (15 out of 60)th of a degree = 16 degrees and 15/60 of a degree = 16 and 1/4 of a degree = 16.25 or there are 60 minutes or arc in a single degree or a degree is made up of 60 minutes of arc
15 'something' are 'minutes' from the sexagesimal division system; that was great for humans, but decimal points are better for calculations. 16°15" is equal to 16.25° as said @@sc6512
We were taught in marine college that there is a GYRO error (1-3 deg.) only ,in all GYRO compasses regardless if it's on a container SHIP or super-yacht.
Ships used to keep a Compass error book presume they still do?, when you swing the Compass (magnetic) off say Glasgow the errors will not be the same in Buenos Aires. Gyro error used to be checked daily by comparing the gyro bearing (usually off repeaters) to the calculated azimuth bearing of a body. Repeaters were checked for alignment prior to leaving port when 'testing gear'. In the UK it was part of the UK Master Mariners orals exam to swing and correct a compass, also presume they still do, good video.
Haha nice comment, - To be honest, I fully understand it all now luckily, but when I was learning it at marine college for the first time- OMG- IT LITERALLY DID MY HEAD IN , and I'm referring to just the basic plotting on a marine chart.Too much stuff to remember to be able to even make a simple chart plot, but once you understand it all, it all seems easy now.
Keep the" Long Aspidestra Flying" ...it is frustrating waiting on the next in a Short Series and there can be much that Intervenes until the Follow up .. At least with. lengthy version n a Range of Topics we can Scroll back and forward until we get the Gist.. Thanks in anticipation 👍👍👍👍👍
Good videos I don’t really care about the length. But I would like to bring everything full circle, and maybe you have already, if you have, send me a link to the video. So the full circle question. You’re in the middle of the Pacific Ocean, it’s 10 AM, it’s sunny, you have a compass, and a Sextant, and a large chart. You know that Hawaii is just over the horizon, but which direction? Hawaii is on your chart. And you know you’re on your chart. How do you figure out where you are?
GPS receivers are rather measuring ranges: They just measure the delays of reception of pulses from several GPS satellites, which are equivalent to their distance to the receiver. Then it's a matter of solving some equations that the receiver does for you, to give latitude, longitude, precision.
Here in the United States, we have the 5 Great Lakes, other places in the world have similar large bodies of water that are not at sea level. It is rather easy sail out of sight of land based objects on these lakes. Every tutorial I have seen on sextant use is for sea level only which doesn't work at the altitude of these lakes. And then that altitude fluctuates based on season and rainfall. Can we determine the altitude of the lake we are sailing on by sextant only? And then how would use that altitude to determine our position?
The altitude of the lake doesn't come into the calculations at all. Rather it is the level reference it gives when sighting the horizon. It is the height of the sextant above the water level that matters, as this is the "dip" to the horizon. If the shoreline is visible, then that is not a true horizon and there will be a big error, but as you can sail out of sight of the shoreline, then the lake horizon is equivalent to sea level. The "horizontal parallax" correction takes account of the distance from the centre of the earth to mean sea level, but the additional height of a lake above MSL will be a fraction of a second of arc, way below what a sextant can measure.
A fix is a position in which the navigator is highly confident. The act of establishing a fix is called "fixing a position" Fixes are already part of navigation by dead reckoning because dead reckoning relies on measures of speed, course. The fix proves the absolute position during a voyage. The fix itself can introduce errors if the reference point is not correctly identified or is inaccurately measured. As a freshman, this will be a challenging and fun topic to meet.
I'm just starting to learn this (63 yrs old) retired and I've always been interested. I'm a sponge !! So Bravo !!! Well Done !!! and thank you
I appreciate the long videos, which combine the different methods together in one video. This simplifies matters considerably by enabling the viewer to group the different techniques that are all related. It helps deduce the diversity of chartwork studies, by refreshing/teaching the various techniques together.
Thank you for all your teaching either way!
Superb series. Just the kind of systematic, linear process my brain needs to get this stuff. Love it.
Longer vids consolidate the info to one 'place' I prefer. Thank You for this. Well done, Sir.
All your videos are extremely useful - short or long - they are well narrated, the animation is great and the information is clear and concise - well done! I have been dancing around celestial navigation for years but the time has come and I will soon buy a sextant. I will be using your videos to get started with it. Thank you!
I'm in ...ahem...the same boat. I'm taking a basic nav/chartwork course starting next month and am going to be using Casual Animation's videos as an addition.
@@harbourdogNL so you're in ahem..,the same boat, in that you've literally been "dancing around the stars "?.
Dancing under the stars?
I like several techniques in one clip± can then stop and review and compare each one. Love this series-I only discovered it the other day. :-)
These videos are fantastic. I like the long format but whatever works for you is perfectly fine. I would love to hear about the use of precision for all of these approaches. Ideally precision would include human factors and a way to characterize the precision in various environments. With this our fixes could have a proper cocked hat or more likely a circle of probable location.
You have made this discombobulating subject become something earthly! Personally i think you are one of the very best teachers in this subject, your work on the Sextant was fabulous, and understandable, however, I perfer the long winded, obvious, and easy to grasp stuff, It needs to be tactile, hammered in and tangible for me, so I thank you all for your patience, but keep on with the videos, I find them very informative, and as a decendant of excellent navigators, you give me hope of understanding the details, perhaps you could tell me how you find the stars?! What where and how, how come, you would know etc!!!/
The deviation card is for the steering compass and is found by "swinging the compass", turning the boat through the points of the compass and noting the deviation. A handbearing compass will have a deviation depending on where you are in the boat and it cannot be corrected for as in the video - the position line shown at 5;55 could be 4 degrees in error. Either a neutral location is found in the boat (by experimentation), or several bearings made from different places in the boat.
Even if the deviation card it's corect (hand compass or not) you should always use the closest value to the course (in this case would be 2 not 4)
@@mariusstan7258 The sailor took a hand-held compass bearing to the lighthouse and applied the steering compass deviation to it. They are two different compasses and the deviation does not apply to both equally.
This is by far the best video
Yes less is best to answer your questions
Yes... Far less is best.. less info per video. So my Sea scouts can go back to just the video they need to review.
Also please be sure to TELL us first what your going to tells us NEW in the first 10 seconds, sentence and paragraph. Then show us then remind us.
Be sure to show it to us mutiple times in a row slowly.
Then tell us what you told us at the end faster ...
Last but most important... always review old info multiple times while adding new info, words and techniques.
All NEW things need to be said and shown multiple times before they sink into the brain
These are just the basic S.O.P. of teaching today as you know.
Great Job
Longer the better. Easier to review. If one video contains the full range of data, but you need to refer to two or more segments of the presentation in order to clear up a mis-understood concept, you can always open multiple copies of the video and "navigate" to the several sections needed to achieve understanding. Not unlike fixing your location using different techniques. IF the videos are long, however, it is necessary to divide them up into chapters that will permit easier seek and find.
I really wish I had had UA-cam when I was 12 ! ! !
Love your stuff. Definitely prefer one subject one tutorial. TMI on the longer vids. Cheers and thanks
All are Best -in-Class for clarity of communication. Short better than long for me. Thank you and congratulations.
Error in your application of compass deviation. 60 degrees compass bearing does not give a deviation of 4 degrees West. The deviation card has compass bearing of 45 degrees resulting in 2 degrees W, and 90 degrees has 0 degrees deviation . I would therefore use 1 degree West as the deviation correction in the example shown.
The deviation is based on the boat heading, not the bearing taken. One presumes the boat is heading North.
So soothing to watch..
That's a tough question to answer. I think both long and short are great. Depends on the complexity of the subject I suppose. Consider all of your audience as noobs or armchair sailors, and do your videos accordingly. They are very, very well done!
The length of video here didn’t bother me , the content is the importance in which case I enjoyed the information from start to finish , great job , liked and subscribed👍
Excellent!
I prefer long format with time stamps for reference!
Very nice, clear explanations!
All the clips are fantastic. long or short! I have been attending courses back and forth all over the UK for the last 8 months and I always come back here for reference....you couldn't come and do my Masters Oral Exam in Belfast on Friday could you???
Ahhh....- Bel-fast..., what if I'm scared of the IRA??
If you need this for your Masters ticket presume you failed? this is very basic stuff
Really like the sort vids, thank you very much.
Single and detailed !
Nice one, learned a lot. Thank you!
The GPS does not have "several LOPs hidden away"!! The position it calculates is the apex of several triangles, pyramids, if you like, coming down from the GPS satellites whose distance it calculated. The apex moves around a little as the calculations are performed, giving the horizontal (and larger vertical) errors of position.
Very helpful. Thanks
very helpful. Thanks
Yes please!!!!
Great job.
Fixing position is important to the navigator a fix is a term is used in "position fixing" in navigation fixes are necessary part of navigation by dead reckoning because dead reckoning relies on estimates of speed course. The fix confirms the actual position during a voyage. As a freshman this will be a challenging and exciting topic to meet, I expect to learn more about this topic this topic.
Questions: 1. If you took a visual bearing of a celestial body and made a note of the time UTC you could calculate the azimuth of the celestial body using LHA, DR Lat and Dec. From the value obtained you could calculate the difference between the visual bearing (compass) and the azimuth (true) which would give you a Total Correction. With this Total Correction you could convert from a Compass Bearing to a True Bearing, and viceversa. Is that correct? 2. Regarding the range, could we use the water depths shown on the nautical chart as a second point / line of position to determine how far we are from the lighthouse if we used a handheld or ship's depth sounder? Thank you for this video. I am going through a learning curve, so any feedback will be much appreciated. Cheers.
you can convert those true bearings to compass bearings, and they are to be used to determine compass error at that heading at that time.
consider measuring sun azimuths to be a way to swing the compass out of sight of land.
for your second question, you can use a depth as an LOP if you're very confident that it forms a line. look on your chart for very dramatic cliffs of depth.
I don't agree . If you take a compass bearing to a known feature ( the lighthouse ) from an unknown position ( your current location ) then you need to convert the final bearing you calculated to a " back bearing " ( add or subtract 180 degrees ) and place the protractor vertical against the grid line 0-360 to North and the center of the protractor is on the lighthouse and then draw the line from the lighthouse through the correct bearing figure on the protractor . You are then located somewhere along that line of sight . There is a slight convergence between the Grid on the map and True North. It's small at the Equator and gets bigger as the grid lines converge at the poles . If you are measuring aligned to the grid lines your not really using a true bearing . Just measuring on my screen that compass rose seems to be orientated to Grid and Magnetic variation and it's not clear if any Grid Convergence is added into the magnetic variation amount .
on compass deviations table: deviation from 000 to 45 are 4 degrees deviation, from 45 to 090 degrees the deviation is 2 degrees, so the Bearing (M) it is 58 degrees not 56 degrees...
Can I consider finally gps position one of position fixing or not
Bearings are taken from ship to object not the other way around, so put arrows appopriate to that
Could someone please explain how 16 degrees and 15 something turned into 16 degrees .25? Is that because 15 is 25% of 60?
I don't think it's correct, since is decreasing, so it should be 16deg15' minus 6minutes (considering it is only one year after the 2018)...Either way, you can't keep a steady course on the compass regarding minutes, you (or the auto-pilot) can barely hold degrees. So a round 16deg should be acceptable for to be taken in to consideration. BUT the theory behind is important, not the small figures.
Also, IMHO, the DEV taken, should have been 1deg W, not 4, because the bearing was 60deg, so in between 45 and 90 (hence, between 2W and 0)
yep your are correct 16 degrees 15 minutes = 16 degrees and (15 out of 60)th of a degree = 16 degrees and 15/60 of a degree = 16 and 1/4 of a degree = 16.25 or there are 60 minutes or arc in a single degree or a degree is made up of 60 minutes of arc
15 'something' are 'minutes' from the sexagesimal division system; that was great for humans, but decimal points are better for calculations.
16°15" is equal to 16.25° as said @@sc6512
No more paper charts in the USofA
Great vid... just wondering, with Gyro, you can assume this to be true when plotting on the chart right?
Yes, because the gyro compass aligns with the axis of the Earth’s rotation, hence with true north.
We were taught in marine college that there is a GYRO error (1-3 deg.) only ,in all GYRO compasses regardless if it's on a container SHIP or super-yacht.
Ships used to keep a Compass error book presume they still do?, when you swing the Compass (magnetic) off say Glasgow the errors will not be the same in Buenos Aires. Gyro error used to be checked daily by comparing the gyro bearing (usually off repeaters) to the calculated azimuth bearing of a body. Repeaters were checked for alignment prior to leaving port when 'testing gear'. In the UK it was part of the UK Master Mariners orals exam to swing and correct a compass, also presume they still do, good video.
Single longer one
It says its for entertainment purposes only but my teacher used this as a study module.
Bunch them together
I like short videos
Working with a sextant video would be great. Thanks
I prefer really short videos
Prefer long format.
Single
long
I’d prefer shorter videos so you can mull over the single tutorial. Thick heads appreciate it.
Haha nice comment, - To be honest, I fully understand it all now luckily, but when I was learning it at marine college for the first time- OMG- IT LITERALLY DID MY HEAD IN , and I'm referring to just the basic plotting on a marine chart.Too much stuff to remember to be able to even make a simple chart plot, but once you understand it all, it all seems easy now.
This world is a terrarium, a built, and stationary growthhouse, not a planet freely in a space!
Keep the" Long Aspidestra Flying" ...it is frustrating waiting on the next in a Short Series and there can be much that Intervenes until the Follow up ..
At least with. lengthy version n a Range of Topics we can Scroll back and forward until we get the Gist..
Thanks in anticipation 👍👍👍👍👍
Single longer one
Good videos I don’t really care about the length. But I would like to bring everything full circle, and maybe you have already, if you have, send me a link to the video.
So the full circle question. You’re in the middle of the Pacific Ocean, it’s 10 AM, it’s sunny, you have a compass, and a Sextant, and a large chart. You know that Hawaii is just over the horizon, but which direction? Hawaii is on your chart. And you know you’re on your chart. How do you figure out where you are?
How do you measure a precice angle with a sextant onboard a moving vessel ?
i think its down to you in what you feel comfortable doing and to et the information you want over
i am happy with both
I like the longer versions, sometimes it’s hard to find the others or I find the second one first and watch them out of order. Great videos!!
Thank you so much for these tutorials! I always wondered how this works, I might even go and buy a sextant now just to play with it :)
GPS receivers are rather measuring ranges:
They just measure the delays of reception of pulses from several GPS satellites, which are equivalent to their distance to the receiver.
Then it's a matter of solving some equations that the receiver does for you, to give latitude, longitude, precision.
Longer video for me.
Here in the United States, we have the 5 Great Lakes, other places in the world have similar large bodies of water that are not at sea level. It is rather easy sail out of sight of land based objects on these lakes. Every tutorial I have seen on sextant use is for sea level only which doesn't work at the altitude of these lakes. And then that altitude fluctuates based on season and rainfall. Can we determine the altitude of the lake we are sailing on by sextant only? And then how would use that altitude to determine our position?
SandhillGuitar Interesting question. I’d be curious to know as well.
The altitude of the lake doesn't come into the calculations at all. Rather it is the level reference it gives when sighting the horizon. It is the height of the sextant above the water level that matters, as this is the "dip" to the horizon. If the shoreline is visible, then that is not a true horizon and there will be a big error, but as you can sail out of sight of the shoreline, then the lake horizon is equivalent to sea level. The "horizontal parallax" correction takes account of the distance from the centre of the earth to mean sea level, but the additional height of a lake above MSL will be a fraction of a second of arc, way below what a sextant can measure.
A fix is a position in which the navigator is highly confident. The act of establishing a fix is called "fixing a position" Fixes are already part of navigation by dead reckoning because dead reckoning relies on measures of speed, course. The fix proves the absolute position during a voyage. The fix itself can introduce errors if the reference point is not correctly identified or is inaccurately measured. As a freshman, this will be a challenging and fun topic to meet.
Great videos! This was awesome and you are amazing with your graphics. I love your channel!
Thank you
This format works
Single longer is great. Thank you.
Helps a lot! Thank you and please continue making maritime related videos.
thank you very much for your efforts
I would die out at sea in a vessel.
Ahh Bar Harbor...what a hole!
Super !
Thank you for these, they’re great. My preference is the shorter videos since often I don’t have time to watch very long.
I prefer 1 TOPIC and EVERY method used under same TOPIC,TYSM