Imray chart c65...what does this mean?

Heights of freestanding rocks in brackets are of course a perfectly standard notation, unrelated to any lights they might or might not have on top. I can’t see the chart in question, but is the spot height perhaps just placed next to the “Lt Ho” and light character, and not intended to be part of either of them?

Pete

Looks like the software might 'join up' the name & drying height?

dryheight.JPG
 
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Depends on which charts you use with Open CPN. The ripped-off torrent downloads are lacking in many details.

That's surprising. I understood they were pretty expensive before being ripped off. MaxSea I believe.
 
Depends on which charts you use with Open CPN. The ripped-off torrent downloads are lacking in many details.

I'm not using ripped off torrent charts. I have legitimate copies of the VMH rastor charts and OpenCPN O-Charts.

The O-Charts are lacking in many details and they also badly affect the performance of OpenCPN, they are slow and clunky when zooming in and out and panning around the charts, for a start.
 
I'm not using ripped off torrent charts. I have legitimate copies of the VMH rastor charts and OpenCPN O-Charts.

The O-Charts are lacking in many details and they also badly affect the performance of OpenCPN, they are slow and clunky when zooming in and out and panning around the charts, for a start.

Is that just on the android app?

I have Ocharts on a Pi and they work fine.

If there are data missing then Ocharts would probably be interested in hearing about it, there are a few known spots with data missing but few and far between, should be Admiralty data.
 
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Is that just on the android app?

I have Ocharts on a Pi and they work fine.

No, i have them on a laptop running Windows 7 and a Samsung tablet running Windows 10. They do work, but are noticeably slower than the VMH charts when zooming, panning etc
 
No, i have them on a laptop running Windows 7 and a Samsung tablet running Windows 10. They do work, but are noticeably slower than the VMH charts when zooming, panning etc

Sounds like something is wrong somewhere...

Do you have opengl turned on in display|advanced? I'm getting between 30 - 60 FPS on a win10 laptop with CM93, panning around in busy area- don't have the Ocharts on here but on the Pi the Ocharts were plenty quick.
 
Sounds like something is wrong somewhere...

Do you have opengl turned on in display|advanced? I'm getting between 30 - 60 FPS on a win10 laptop with CM93, panning around in busy area- don't have the Ocharts on here but on the Pi the Ocharts were plenty quick.


Do you have the VMH raster charts to make a comparison ?
 
Do you have the VMH raster charts to make a comparison ?
Nope, but lots google earth images saved as KAP files. They look like around 100FPS, a not very busy area of CM93 is closer to 150FPS.

Ocharts (& CM93) were fast enough on the Pi, can't remember the FPS. That was with the sometimes grumpy hardware graphics driver turned on & opengl.
 
Looking at the charts took me back.
Mid seventies, our first cruise in our Trapper 300, first time west of the MoK, outboard engine, wife and weans, no GPs Decca or such, just a depthsounder, an RDF and dead reckoning, stopped at Port Askaig, then Colonsay where in those days you could anchor close in south of the ferry pier off the slipway, set off in the morning, no wind and bright sunshine as we headed north for Iona, as we cleared the island the fog descended, the only chart we had was really scary, isolated rocks right across our passage. As we approached we could hear the swell breaking so we diverted west to leave all the Torran Rocks to starboard then tried to find our way back east in to the Sound with only the depthsounder to help, started getting very shallow so guessed we were in the Sound then a faint loom of land to the west to confirm, still only about 300 yards vis. when we anchored. So relieved we all headed straight ashore leaving the boat swinging in the tide on its CQR. It held!!!! The hardest thing was hiding from the family just how scared sh1tless I felt.
To this day I still. find the Torran rocks really scary
 
LT HO Dubh Artach (14) Fl(2)30s44m20M.


LT HO – Light House
Dubh Artach (14) - Black Rock (height of14 metres above chart datum)
Fl(2)30s – Flashes twice every 30 seconds
44m light height of 44 metres above Mean High water Springs
20M Light range of visibility 20 Miles
 
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