Now here is a name for an effect that I have observed and been puzzled about!
Alexander’s dark band – – Alexander of Aphrodisias first described the effect with double rainbows in 200 AD and it now carries his name.
Light rays undergoing a single reflection in raindrops form the primary rainbow or brighten the sky inside it. Rays reflected twice are deviated to form the secondary bow or brighten the sky outside.
Raindrops along lines of sight between the two bows cannot send light to your eye and so the sky is darker there.
You can see the effect in this image I posted a year or so ago.
Read more at https://www.atoptics.co.uk/rainbows/adband.htm or https://en.wikipedia.org/wiki/Alexander%27s_band
All from Baked Bean cans within a 10 mile radius, using Ilford Multigrade B&W paper. Scanned and played with in Photoshop.
Andy’s first one, slightly different angle to his usual version.
And his second – massive amounts of water damage (was still a few mm of rain in the bottom of the can), but love the effect it’s created. This is his usual angle (so can be compared to previous attempts). Can just make out the house bottom right of centre and the tree to the left.
Mine, screwed to the house, SSE facing.
Sister’s from her new home. Was surprised at the very upper sun trace, but it can be matched to my own above. Thought at first it must have moved or have been a reflection from the inside top of the can. The cans are painted black inside and any movement would have created a double image of the houses – there isn’t anything to suggest that.
One I made up for a lady at my new workplace.
My works Nikon D7000DX (APS-C) and my own (full frame) Nikon AF-S 24-70mm f/2.8G ED, hand-held out the bedroom window.
Jpegs straight off the camera.
7.09am ISO125 1/20 f/2.8 84mm (Focal length in 35mm)
7.34am ISO100 1/50 f/3.2 82mm (Focal length in 35mm)
7.35am ISO100 1/60 f/3.5 70mm (Focal length in 35mm)
7.35am ISO100 1/60 f/3.5 82mm (Focal length in 35mm)
Nothing much astronomical on our recent trip around around the North Coast 500 in Scotland. (https://www.visitscotland.com/see-do/tours/driving-road-trips/north-coast-500/) Fantastic, by the way. Totally lives up to its billing as “Scotland’s stunning answer to Route 66 – – – named one of the top coastal road trips in the world”)
However, lots of nice atmospherics – rainbows and crepescular rays. Here are a few of them.
The last one I couldn’t resist posting – Salmon leaping to get a better view of the sky at the Falls of Shin!
Just had a hefty thunder storm over the hills from Westendorf, Austria.
I quickly downloaded the iLightningCam app that Ed mentioned (well the free version to trial)!
This was the result from having a play with the settings sitting on the balcony from our room (hand held no less)…
Damian, Rhys and I took a fluorescent bulb and stood under the electricity pylons on Dartford Lane just past the A38 bridge. We had heard that bulbs would illuminate…..and it did indeed do just that. Closest we have ever been to owning a light sabre!
Yes, the same ones Andy has also posted!
Woke up, looked out the bedroom (back) window… could see them bright as anything. Shot round to the front and grabbed camera. Couldn’t get the angle from my office window. Tried Julie’s office window (also on the front), but no joy… Headed downstairs in dressing gown and into back garden. Pulled wheelie bin out (for small tripod) but still no joy! Opened side gate and plonked tripod on car roof and started taking pictures…. rang Andy’s mobile – no joy, rang house number…. got a pretty vacant “…..heeellloooo…”. I think my curt response went something like…” Andy, it’s me, you need to get your arse outside, Noctilucent clouds..!”
This is a 1 second exposure @ f/2.8. ISO 200, 48mm focal length was shot at 3.30am on Friday morning 6th July 2018
My trusty old full frame Nikon D3 on a small travel tripod, itself sitting on my car roof.
Off the iPhone6…
On Friday evening after RAG, members of the astronomy group were invited to walk down to the Moth Group’s moth-observing area further in the forestry centre. It’s fantastic when scientific groups can share information and experiences. They showed us many beautiful moths but they did not have any examples of this intimate pair which Damian, Ean Ean and I saw on Saturday evening on a walk in Lichfield (the day after RAG) – these two are Six Spotted Burnet moths and were visible in broad daylight – I had not known that was possible until the moth folks told us that some moths were active in the day, and indeed Six-Spotted Burnets are one such species.
The following information comes from https://butterfly-conservation.org/1034-1540/six-spot-burnet.html
Six-Spotted Burnet Moths. Scientific name: Zygaena filipendulae
June – August. All over Britain, mainly coastal in Scotland. Medium-sized black moth with six red, occasionally yellow, spots. Frequents flowery grassland, woodland rides and sandhills.
The only British burnet moth with six red spots on each forewing, although care must be taken with identification, as in some cases the outermost spots can be fused. Rarely the red colour is replaced by yellow.
Flies with a usually slow buzzing flight during sunshine and is attracted to a range of flowers including thistles, knapweeds and scabious.
Size and Family
- Family – Burnets and Foresters (Zygaenids)
- Medium Sized
- UK BAP: Not listed
Particular Caterpillar Food Plants
Common Bird’s-foot Trefoil, but also occasionally on Greater Bird’s-foot Trefoil.
- Countries – England, Wales, Scotland, Ireland
- The commonest and most widely distributed burnet moth in the UK. Well distributed in England, Wales and Ireland, becoming more coastal in Scotland and found on the Outer Hebrides. Also found on the Isle of Man and the Channel Islands.
Frequents flowery grasslands, including downland, cliff-edges, woodland rides, roadside verges and sand-dunes