Greenwich Prime Meridian

[evacguy]

Vista from the Old Royal Naval College looking towards the Royal Observatory Greenwich. The meridian (green) laser can be seen marking the route of the Greenwich (Prime) Meridian in a northerly direction from the Royal Observatory. I'm continually impressed with what the A7iv can do in low light - ISO 32,000! Post processing is in LRC, and I made use of the AI Noise Reduction option, I think that was cranked up to 35%.

• ILCE-7M4
• FE 24-70mm F2.8 GM II
• 47.0 mm
• ƒ/7.1
• 1/50 sec
• ISO 32000

 

[Alan Clark]

I think I would have made use of the equally impressive image stabilisatation that is possible. 5 stops of stabilisation would allow a shutter speed of around 0.5 seconds at ISO 1000. This would benefit the shadow detail. Even so, your result is impressive.

BTW, the meridian line at Greenwich is not at zero degrees, it is about 102 meters from where it should be.

The Real Greenwich Prime Meridian

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

www.atlasobscura.com

 

[evacguy]

I think I would have made use of the equally impressive image stabilisatation that is possible. 5 stops of stabilisation would allow a shutter speed of around 0.5 seconds at ISO 1000. This would benefit the shadow detail. Even so, your result is impressive.

BTW, the meridian line at Greenwich is not at zero degrees, it is about 102 meters from where it should be.

The Real Greenwich Prime Meridian

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

www.atlasobscura.com

Hi Alan, yes the meridian line is actually about 100 m from the original line - I've found it using satnav. Many thanks for the info about the shot. I thought the image stailisation was on unless you turn it off? I'm thinking of the Steady Shot option or do you mean something else?

 

[Alan Clark]

I didn't know if you had Steady Shot (=stabilisation) turned on or off, but with that shutter speed you can get a sharp image regardless. At 0.5s you should still get a sharp image with Steady Shot, but with better shadow detail.

 

[evacguy]

I didn't know if you had Steady Shot (=stabilisation) turned on or off, but with that shutter speed you can get a sharp image regardless. At 0.5s you should still get a sharp image with Steady Shot, but with better shadow detail.

Oh, I see what you are saying. Thanks, will try that again with the settings you suggest. Thanks for the advice.

 

[Thad E Ginathom]

Modern instruments pointed out that, due to inaccuracies in the instruments used at the time the meridian line was established, it was marked 102 meters (334 feet) west of its actual position.

It is so utterly important for navigation and mapping (and probably a few et ceteras) that I'm sure they know what they are talking about. But isn't it arbitrary? As in, the French wanted it somewhere else, but lost the battle, and if it had not been for the supremacy of Europe in might not even have been in that part of the planet.

 

[Alan Clark]

If the meridian had gone through Paris we would have PMT instead of GMT.