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rgleason · 26-02-2018, 14:48

Note this post please. It works.

http://www.cruisersforum.com/forums/...ml#post2585887

Quote:

Originally Posted by boat_alexandra

I think the code it's broken for this case unfortunately. It might not be too difficult to fix.

Uwe, I'll make a PR for Sean of the additional Aviation images that you've completed.

HUR450502 · 27-02-2018, 03:44

Dear Rick and Sean,

sorry, I am not able to get the "sat_irbw_g.jpg" picture calibrated. Maybe I am doing something wrong here. Rick, for you it has worked, as I see, can you give me the steps you did, and the x and y values?

Also - I am using Weatherfax 1.8 - for some reason I downloaded that one. However, I do not think that there have been changes in the algorithms - am I wrong?

Maybe I should list my steps here:

1. I downloaded the picture
2. Started calibration using for the upper left corner 70°N; 020°W (the red lines)
3. Used for the lower right 0°N and 90°E (the red lines)
4. specified "Polar" projection
5. Adjusted the Pol "X" value to 387
6. Adjusted the Pol "Y" value to 30 (+30!!)

With this, the "blue lines exactly match the parallels of the sat image.

When I click on the button to get the "side-relationship" I get to a value of - (minus) 0.7084.

When I then press next, the calculator starts and I get a white "image" on the map. the picture seems to be mirrored outside the given values.

If I repeat all steps and press teh "get Drawing" button prior to going to next, the blue lines are completely distorted representing elliptical figures and the picture finally is created too in a distorted way.

So, something I am doing wrong here, or something is wrong - I was surprised that the Pol "Y" value had to be positive to get matching lines as well as the "side-relationship" got a negative value.

does this give you any hints as to what may be wrong with my attempt here??

Thanks a lot for your help. ....

Best regards,

Uwe

rgleason · 27-02-2018, 04:42

Uwe,
Polar files are calibrated slightly differently than using cross corners.
I often use the red coord centered on the middle of the polar file and at a high latitude.
Then I pick a coord crossing to the south and off to one side.
Then I start counting coordinates and trying to get them right.

INstalll the two files I provided. Then pick Aviation Weather / Sat Image Polar
Then select the one file and download it.

Then highlight it and go to edit, you will see how the coordinates are selected.

Quote:

Quote:

See the Manual Polar Wizard

https://opencpn.org/wiki/dokuwiki/do...ar_projections

rgleason · 27-02-2018, 06:35

Quote:

Originally Posted by boat_alexandra

Not yet. Suppose I supported date and time formatting in the url.

Which services besides just metservice nz would this give us?

HUR450502 · 27-02-2018, 07:00

Dear Rick, dear Sean,

Rick, I tried the values you used - and it works like a breeze ..... :-)

However, if you change the input just slightly.... e.g. use 80°N and 60°E (instead of 65° - which are not shown on the input picture - I have a tendency to "click" on the shown lines to avoid "estimating") you get slightly different outputs. I tried this with a number of different points - to avoid to get into negative longitudes, I only took either 0° or any easterly longitude as the first input point but still I got all sorts of errors, e.g. starting with the drawing program which tells me, that the drawing contans negative dimensions, or when clicking on "Get drawing" (sorry, I translate the German text here) suddenly the blue lines change as well as the values in the Pol "X" and Pol "Y" input fields etc. ....

So, there seems to be some problem in the code I would say. At least for a lay-man this is difficult to handle.

Anyway, it looks as if this can be circumvented by using the "correct" points in the first place and then do the calibration.

So, Sean, no "severity 1" problem :-)

However, I think - from my point of view - as said before, there is some problem in the coding. If you agree, I think - somewhere in the future - this should be solved....

For the time being, Rick, I think, yes, we should be using and publishing the "easier" mercator sat-images, so everybody can use them. Especially the Water Vapor and the NWS charts look very useful to me in estimating the weather to come ....

Thank you all again, for working on these excellent plugins, I use weatherfax a lot and I am absoluetely convinced of its value to sailors everywhere. ....

Best regards,

Uwe

seandepagnier · 27-02-2018, 07:57

Quote:

Originally Posted by rgleason

Page not found

Quote:

403 Forbidden

Quote:

Not Found

The requested URL was not found on this server.

Quote:

<!-- UK MET
Metoffice requires year month day time to set correct url
http://www.metoffice.gov.uk/weather/...1405240600.jpg
http://www.metoffice.gov.uk/weather/...1405240000.jpg
http://www.metoffice.gov.uk/weather/...1405231800.jpg

Not found

Quote:

How do I determine the product id??

Quote:

seems to work

Quote:

Despite the date after the ? I only get the latest forecast for febuary 28 2018
This is no changing url, we can already use it

Quote:

Global Model Interactive Forecast Maps
Interactive Weather and Wave Forecast Maps
12utc Tues 1 Today
http://www.bom.gov.au/charts_data/ID...png?1501588800
12utc Wed 2
http://www.bom.gov.au/charts_data/ID...png?1501588800
12utc Thur 3
http://www.bom.gov.au/charts_data/ID...png?1501588800
http://www.bom.gov.au/charts_data/ID...png?1501588800
Nope they are not unique.
Interactive Weather and Wave Forecast Maps
http://www.bom.gov.au/charts_data/ID...png?1501588800
It is just swapping the new image in using the same name!

Southern Hemisphere MSLP Forecast Maps
Surface Pressure & Rainfall
Interactive Weather and Wave Forecast Maps
http://www.bom.gov.au/charts_data/ID...png?1501588800
MLSP & thickness
Interactive Weather and Wave Forecast Maps
http://www.bom.gov.au/charts_data/ID...png?1501588800

Indian Ocean MSLP
Indian Ocean MSLP Analysis
Pacific Ocean MSLP
Pacific Ocean MSLP Analysis
Asia MSLP Analysis
Asia MSL Pressure Analysis Valid 00UTC

Gradiant Wind Analyis 00z
Gradient Level Wind Analysis Valid 00UTC
Gradiant Windd Analysis 12z
Gradient Level Wind Analysis Valid 12 UTC
Pacific Ocean Gradiant Wind 00z
Latest Pacific Ocean Gradient Level Wind Analysis Valid 00UTC
Pacific Ocean Gradiant Wind 12z
Latest Pacific Ocean Gradient Level Wind Analysis Valid 12UTC
Indian Ocean Gradiant Wind 00z
Latest Indian Ocean Gradient Level Wind Analysis Valid 00UTC
Indian Ocean Gradiant Wind 12z
Latest Indian Ocean Gradient Level Wind Analysis Valid 1UTC

These are not images, they are .shtml.

rgleason · 27-02-2018, 09:57

Well Sean, what can I say. These a worked at one time, but are now outdated.
Here are some new

https://www.meteoblue.com/en/weather/map/pressure/asia#

sailing singapore asia indonesia surface pressure (gfs) + 6 utc

Gradient Level Wind Analysis Valid 12 UTC

Japan Meteorological Agency | Weather Maps
http://www.jma.go.jp/en/g3/images/asia/18022721.png
http://www.jma.go.jp/en/g3/images/asia/18022715.png
http://www.jma.go.jp/en/g3/images/asia/18022721.png
http://www.jma.go.jp/en/g3/images/asia/18022703.png

Japan Meteorological Agency | Weather Maps
http://www.jma.go.jp/en/g3/images/24h/18022709.png

Japan Meteorological Agency | Weather Maps
http://www.jma.go.jp/en/g3/images/24h/18022709.png

sailing asia japan sea of japan wind (gfs) + 6 utc

rgleason · 27-02-2018, 10:50

http://www.weatheronline.co.uk/daten...2018022706.gif

rgleason · 28-02-2018, 11:11

Sean, thank you for the Japan,http://www.jma.go.jp/en/g3/ UK and other examples with strdate.
I downloaded and compiled it and tried it.
The first Japan "Analysis" is searching for
http://www.jma.go.jp/en/g3/images/asia/18030103.png which is not found.

From the xml file

HTML Code:

  <Server Name="Japan Meteorological Agency" Url="http://www.jma.go.jp/en/g3/images/asia/">
    <Region Name="Japan">
      <Map Url="%y%m%d%H.png" Contents="Analysis Now" Area="1" Hour="6;6;3" />
      <Map Url="%y%m%d%H.png" Contents="Analysis -6" Area="1" Hour="0;6;3" />
      <Map Url="%y%m%d%H.png" Contents="Analysis -12" Area="1" Hour="-6;6;3" />
      <Map Url="%y%m%d%H.png" Contents="Analysis -18" Area="1" Hour="-12;6;3" />
      <Area Name="1" lat1="0N" lat2="70N" lon1="90E" lon2="180E" />
    </Region>

Analysis Now does not seem to work. Is this because the "Analysis Now" Hour="6,6,3" are off somehow? I am still scratching my head about how you arrive at the "hours". Can you give us a brief explanation?

UTC 12:00 Feb28 http://www.jma.go.jp/en/g3/images/asia/18022821.png
UTC 6:00 Feb28 http://www.jma.go.jp/en/g3/images/asia/18022815.png
UTC 0:00 Feb28 http://www.jma.go.jp/en/g3/images/asia/18022809.png
UTC 18:00 Feb27 http://www.jma.go.jp/en/g3/images/asia/18022803.png

UTC Time "Now" in Japan?
Japan Standard Time is 9 hours ahead of Coordinated Universal Time
7:16 PM Wednesday, Coordinated Universal Time (UTC) is 4:16 AM Thursday, Japan Standard Time (JST)
in Eastern Standard time it is 2:17pm now.

So for an "Analysis Now" day and hour you would want 18030103.png
Some of the others for that day would be 18030109.png , 18030115.png, 18030121.png
I guess this 18030103.png image is just not available yet on the server?

rgleason · 28-02-2018, 11:43

It would be very helpful to be able to right click or copy the generated URL for an image. It would help us figure out what isn't working right.

See this image please. If we could just copy the URL that would be good.
Or perhaps just allow us to highlight an image, and then right click and pick "Copy URL"?

In this example, the

HTML Code:

Server Name="Weather Online" Url="http://www.weatheronline.co.uk/daten/sailcharts/gfs/">
    <Region Name="Great Britain">
      <Map Url="%Y/%m/%d/pslv_grbr_06-%Y%m%d%H.gif" Area="1" Hour="-9;6;0" />
      <Area Name="1" lat1="48N" lat2="60N" lon1="12W" lon2="6E" />
    </Region>

url does not seem to be working...

http://www.weatheronline.co.uk/daten...2018022812.gif does not seem to work

but this one for WeatherOnline Asia does work
http://www.weatheronline.co.uk/daten...2018022800.gif does work and is UTC+06

http://www.weatheronline.co.uk/daten...2018022806.gif slightly different chart same UTC 60

http://www.weatheronline.co.uk/daten...2018022818.gif not avail
http://www.weatheronline.co.uk/daten...2018022824.gif not avail
http://www.weatheronline.co.uk/daten...2018030100.gif not avail

rgleason · 28-02-2018, 14:01

I've made a compilation of the latest changes and improvements:
1. Uwe's Aviation extensions and revisions.
2. Rick's Aviation "polar" example.
3. Sean's UK Met & Japan Met "strdate" examples. (at the bottom)
4. Note that there is a Singapore example further up that is no longer working completely. We can probably change that to use %y%m%d%h and it might work.

I am attaching the following files as a zip, please remove the "doc"
The third file is a ll the URL's previously removed which do not work due to strdate. The xml files have been validated. Sean's Japan "Analysis Now" seems to be working again. (It depends on the time of day I guess, when the image becomes available.)

I will be making a PR next. Don't forget that once Sean accepts the PR, you can easily update your XML files by using
"Retrieve > Update Data Sources"!

rgleason · 28-02-2018, 18:57

I've been trying to get Singapore Met working with strdate.

These are the main urls that work today, NOW:

Quote:

These are the URL's changed to use the strdate for Data and Hour.
There is a problem with SurfaceWinds right now because the the date is still one day behind
at

Quote:

/surfacewinds/surfacewinds_24Hr_20180228_213000.gif

Quote:

I am also wondering what the _103000.gif is for? Is that hours?
How do we handle those?

rgleason · 28-02-2018, 19:16

These files have the Singapore Met URL's updated as far as I can get.
The bottom ones work right now.

rgleason · 01-03-2018, 08:42

Have made some notes about strdate. Would like some help and advice so we can develop some syntax and examples using strdate code.

https://github.com/seandepagnier/wea...x_pi/issues/58

rgleason · 01-03-2018, 09:01

Here is an excellent source for thumbnail weatherfaxes
New Zealand Weather Forecasts

http://metvuw.com/ows/ Ocean Weatherfax

"generated by software written and maintained by James McGregor. Chart plotting is powered by Generic Mapping Tools (GMT). The data used is obtained from the United States National Weather Service. These charts are updated approximately every 6 hours and provide forecasts up to 192h ahead of the time they were issued."
Some documentation about the command line tool http://gmt.soest.hawaii.edu/doc/5.4.3/pdf/GMT_API.pdf

I think we should incorporate these thumbnails into the wxfax pi.

Here is an AUS radiofax schedule
http://www.bom.gov.au/marine/radio-s...schedule.shtml

AUS Maps http://www.bom.gov.au/australia/charts/?ref=ftr
AUS SLPM http://www.bom.gov.au/australia/char...ptic_col.shtml

80 page pdf of Metservice about weatherfax, looks old. Has schedules https://about.metservice.com/assets/...aps-by-Fax.pdf

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