Rainbow

Sparrow

Veteran
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6:48 PM
Joined
Feb 25, 2006
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Perfidious Albion
Really beautiful rainbow, against a battleship sky, over the flooded Aire valley this morning, could have framed one of the old trees bang in the middle, reflections the lot, the “take everywhere cam” was in my case in the office! Luckily I don’t do landscapes, and the 35mm wouldn’t have been wide enough anyway.
Anyway the question is what field of view do you need to take in both ends of a rainbow? Anyone know
 
The primary radius angle is about 42 degrees, the amount of the full cicrile you see is dependent upon the sun angle above the horizon and your height above. The secondaries are further out a 16mm fish eye or 16mm rectilinear is ideal if you really want to encapsulate what you see.

Go for a moving traffic violation the next time, hee hee

Noel
 
What about a 12mm rectilinear? I was about 10ft above the water and looked as if it might form a full circle with its reflection, couldn’t pull over to find out unfortunately
 
360 degree fish eye or FSU pano or 12mm would be wider than a 16mm, but you will have trunk (boot in UK) full of cam. I hill walk and have a 16mm Oly fish (well compact and light) but never carry it, I would be too fit if I carried a kitchen sink...

Where do you live and what time of day, the sun angle is dependent upon both, if you are on a peak or in a helo then you see more of the circle, a water reflection would be a bonus...

Noel
 
West Yorkshire in the UK the Aire valley is just 17m above sea level, it looks like from the map, and it was about 13:30 GMT. The lens is the cv12 so without the filter it’s tiny, tomorrow’s weather has the same forecast, and I was wondering if it was worth the trip, I think I’ll just take everything 35 and under
 
Stewart

There are two bits of bad news

- you are close to optimum angle
- chasing rainbows is like hunting unicorns, but you got me to do sums!

The optimum angle (with sunlight) is 42 degrees again. At winter solstis in N hemi at mid day the sun is 45 degrees (approx) off vertical, and 45 degrees off your line of sight(LoS), if you were at 22.5. At 13.30 the loS angle will be less as the sun Westerns and will be closer to the magic 42, you are lower angle at UK.

If you are using chrome I'd bracket 1/2 stop to try and get the secondary just right.

But you knew to take all your lenses. Hey I'd like a 12mm and a pano, but I'll live with my 2x16mms.

Good hunting...

Noel
 
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