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Mark A
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« Reply #15 on: August 10, 2026, 18:49:22 » |
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It's odd, the amount of light provided by a mostly obscured sun's disk. After the 1999 event, someone kindly provided me with a set of figures from a data logger that they'd set up at Carn Brea (the hill near Land's End rather than the one above Redruth). Despite, subjectively, the light levels dropping during a partial eclipse - while also gaining peculiar qualities - that plunge in light levels during the total phase then comes as more than a bit of a shock - and then, if partly cloudy, the abruptly dynamic appearance of the sky as the shadow tracks across...
Mark
That graph is misleading, or at least its annotation is. The physical light level (in lux) varies almost linearly over most of the eclipse, with no sharp dip. It's the subjective brightness that we notice that gives the rather logarithmic shape in that graph. A cube-root-law model fits the eye better, but the shape on a graph looks very similar to logarithmic. From what I recall, if you don't know there's going to be a partial solar eclipse, even a near miss, you probably won't notice it at all. Even if you are outdoors in bright sunlight, you won't be looking at the face of the sun so as to observe its shape change. The dimming is very slow and subjectively it doesn't darken much. That's why a total eclipse can sneak up on you, until at the last minute the world suddenly goes all dark. That goes for birds too. I must see if I still have the figures - I hold my hand up to simply slapping them into Excel and asking it to plot a graph. In one way the change in lighting during a partial eclipse wouldn't be noticed by many, things do go a bit weird though - shadows described as sharper, and the illumination gaining a metallic quality. I've just looked out my photos of the March 20th 2015 partial eclipse and was surprised at how deep it was, yet, subjectively the hit to light levels though noticeable was as that graph might suggest. The light, though, did gain a strange quality and then of course all those little crescent shadows beneath trees. Mark |
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stuving
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« Reply #16 on: August 10, 2026, 20:30:50 » |
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I've seen no sign the main TV▸ channels have picked up on the eclipse, at least not so as to get it mentioned in listings or EPGs. Which is odd, as while it may be "only a partial", it falls during live broadcast segments for most of them. The start coincides with news for BBC1 and ITV, and local news I'm sure will cover it. C4 news will see "peak dark", and for BBC2 and ITV1 that comes during sports OBs. I'm sure the technical side can make sure they have the right filters etc, but how will the commentators for the athletics in Birmingham or the football at Croke Park cover it?
Well, I just heard Steve Cram ask "will we get a view of the eclipse on Wednesday?" Andrew Cotter didn't know, but at least the commentators can set about doing their research (or getting it done).
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Mark A
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« Reply #18 on: August 10, 2026, 22:19:39 » |
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Chris from Nailsea
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« Reply #19 on: August 11, 2026, 19:01:58 » |
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From the BBC» : Eclipse chasers scramble for glasses as stocks run low
At a bakery in central London, stock has been flying off the shelves.
"I've sold, like, 100 this morning," a staff member tells the BBC. But it's not baked goods driving queues out of the door - customers are here to buy eclipse glasses.
They are among those hoping to catch a safe glimpse of Wednesday's solar eclipse - the UK▸ 's most significant since 1999 - but struggling to get their hands on the right gear.
Experts have urged eclipse enthusiasts not to look directly at the Sun - with even brief exposure causing lasting damage - and to seek out specialist glasses instead.
But online, pairs that meet safety specifications have all but sold out. Those still available either require a hefty next-day delivery fee or simply cannot arrive on time.
Even the Royal Museums Greenwich - recommended as a reputable retailer by UK health officials - has sold out, citing an "unprecedented volume" of orders.
Meanwhile, eclipse glasses have been turning up for sale in unexpected places as retailers try to capitalise on the demand.
"I Googled 'where can I get eclipse glasses but not through the post', because I realised I was too late," one customer waiting to buy three pairs at the bakery on Monday tells BBC Radio 4's PM programme.
"People have been struggling to find them all over," says another.
With around 90% of the Sun set to be obscured by the Moon, the UK is expecting its most significant eclipse in 27 years.
The right glasses should have the international safety standard ISO 12312-2 printed on them, the UK Health Security Agency (UKHSA) has advised, and the lenses should not be scratched, torn or damaged.
It has also advised buying a new pair rather than using ones from 1999, and to take caution when it comes to glasses being sold online as the scramble for safe spectacles has prompted eclipse chasers to trawl social media for tips.
(BBC article continues)
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William Huskisson MP▸ was the first person to be killed by a train while crossing the tracks, in 1830. Many more have died in the same way since then. Don't take a chance: Stop, Look, Listen.
"Level crossings are safe, unless they are used in an unsafe manner." Discuss.
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bobm
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« Reply #20 on: August 11, 2026, 19:21:32 » |
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Not smug or anything but I bought solar filters for my camera back in February. Earlier this week the same supplier had them advertised at 75% more then I paid.  |
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TonyK
Global Moderator
Hero Member
Posts: 6753
The artist formerly known as Four Track, Now!
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« Reply #21 on: August 11, 2026, 20:34:16 » |
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This could be why Octopus is offering me a reward if I use less power during the eclipse. I'll be somewhere on Exmoor, so no problem. |
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Now, please!
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stuving
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« Reply #22 on: August 11, 2026, 20:45:18 » |
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Not smug or anything but I bought solar filters for my camera back in February. Earlier this week the same supplier had them advertised at 75% more then I paid. Are you sure? Did you get a smug filter too? |
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broadgage
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« Reply #23 on: August 12, 2026, 13:12:35 » |
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The decline should not be that serious, as it is towards the end of day when solar power declines in any case. |
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A proper intercity train has a minimum of 8 coaches, gangwayed throughout, with first at one end, and a full sized buffet car between first and standard.
It has space for cycles, surfboards,luggage etc.
A 5 car DMU▸ is not a proper inter-city train. The 5+5 and 9 car DMUs are almost as bad.
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Mark A
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« Reply #24 on: August 12, 2026, 14:24:09 » |
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On the opposite end of that see-saw, the eclipse lands bang in the middle of the evening peak: electricity generation vs consumption data is going to be... absorbing**.
Mark
** Varies by individual and also, various different values of 'Absorbing'.
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broadgage
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« Reply #25 on: August 12, 2026, 15:11:01 » |
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On the opposite end of that see-saw, the eclipse lands bang in the middle of the evening peak: electricity generation vs consumption data is going to be... absorbing**.
Mark
** Varies by individual and also, various different values of 'Absorbing'.
I very much doubt that there will be any serious consequences for electricity supply. The eclipse has been known about for a long time, and any shortfall in generating capacity will be met by pumped storage generation, or by quick starting OCGT▸ plant. Demand is reduced at this time of year if compared to winter. |
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A proper intercity train has a minimum of 8 coaches, gangwayed throughout, with first at one end, and a full sized buffet car between first and standard.
It has space for cycles, surfboards,luggage etc.
A 5 car DMU▸ is not a proper inter-city train. The 5+5 and 9 car DMUs are almost as bad.
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old original
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« Reply #26 on: August 12, 2026, 15:45:47 » |
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I expect Falmouth to be busy as it's annual flying display is taking place at the same time as the eclipse. No Red Arrows this year but there are three separate display teams flying.
Truro - Falmouth branch half hour service extended to end of the day and FMT closed due the expected congestion
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8 Billion people on a wet rock - of course we're not happy
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Mark A
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« Reply #27 on: August 12, 2026, 17:11:32 » |
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Yup, eminently predictable and able to be planned for. A useful 'Teachable moment' for consumers close to the start of the era of electricity consumption pricing by the half hour, though.
Mark
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Mark A
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« Reply #28 on: August 12, 2026, 17:13:04 » |
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Up and down the country, the owners of gas-fired power stations will be sitting by the phone, willing it to ring...
Mark
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ellendune
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« Reply #29 on: August 12, 2026, 17:23:41 » |
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Up and down the country, the owners of gas-fired power stations will be sitting by the phone, willing it to ring...
Mark
Up and down the country those of us with solar batteries and arrangement to balance the grid are on notice to sell electricity from the battery to the grid between 6 and 8pm tonight! |
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