A Quick look at the coordinates in the back show that my estimates for the Delamere origin are aout by a little bit. My estimates for the offset from the bottom left of the map were:
3640 and 46291 feet
Yloande states the values as
3690 and 46100
so I’m out by 50 feet East/West and 191 feet North/South

Hopefully these new values will reduce the alignment errors. Though since I’m seeing up to 600 feet N/S I’ve still got a bit of work to do.

I shall be checking my automatic cassini calculations for the corners of the maps against the printed lists to see if I can see any discrepancies that I can correct.

Further notes:

I’ve just run a quick test and my calculations for the bottom left hand corner of map 116 are definitely out!

I get
51?13’54″14959/0?24’40″69606 (-709110,-711380 cassini feet)

and Brian Adams gets
51?13’54″13/0?24’40″72 (-709110,-711380 cassini feet)

Clearly a difference in the Lat/Lng but not in the cassini coords.

Another look at the Y Hodson book I notice that the “Constructional Elements” section p.255 says the unit is a Foot (Ordnance Survey Foot of 01 which it then states as:
1 Foot of 01 = 0.3048007491 international Meter. Previously I was using 0.3048

Plugging this little gem in I now get
51?13’54″13165/0?24’40″72226 (-709110,-711380 cassini feet)
compared against
51?13’54″13000/0?24’40″72000 (-709110,-711380 cassini feet)

Woo Hoo!

Once uploaded this will bring the total number of 4th Edition England and Wales maps to 29 out of a total of 146, that’s just a smidge under 20%.

This also marks a milestone – I’m going to stop spending new money on maps and start selling old maps to get the money to buy new. We’ll see how long that goes on for! An ideal would be to complete the maps without spending any more money.

The page now goes to a php script on godaddy so there’s no redirect involved, this should result in a small performance improvement.

Four new maps have been added ,
36 – manchester – from Joyce Whitchurch’s scan
70, 60 east wales – from Mike Dat’s scans
77 – from another ebay map.

The maps are now slightly better stitched which will reduce the number of black areas between adjoining maps.

The maps still have the 200 meter mis-alignment problem.

I’ve ordered the Yolande Hodson book from the Charles Close Society, with any luck this will give me a further clue to the mis-alignment issue.

Current Stats are:

This can’t go on forever beause I’m going to run out of space. Currently looking for a new host for the tiles.

I don’t know if there’s a special problem with primitive hosting or not, but the DNS doesn’t even resolve at the moment.

I’m going back to my fallback plan.
Level 3 tiles : 230MB hosted on ponies (limit approx 500MB)
Level 4 and other tiles: 110MB hosted on plus.net (limit 250MB)

This should give me enough room for the moment. I’m probably going to cancel Primitive Hosting. They may be cheap, but they really are crap!

I’m now automatically geo-referencing many of the scans using a cassini projection.

This brings the number of maps to:
4th Series: 18
other: 10

Stats:
The total size of all the maps at all resolutions:

• 03: 232.53 Meg
• 04: 80.34 Meg
• 05: 23.13 Meg
• 06: 5.55 Meg
• 07: 1.53 Meg
• 08: 0.48 Meg
• 09: 0.13 Meg
• 10: 0.06 Meg
• etc.

The number of 256×256 tiles: approx 25000
Time taken to generate the bottom two layers of tiles: 1 ½ hours (1.2Ghz AMD, 1Gb RAM)