Re: Yosemite Falls moonbow

This is from this month's issue of Sky and Telescope.

I attempted to photograph it back in April but it was overcast and we had no moon. From what I heard, I was a day late getting there as it was clear the day before.

What I like about S&T's "gallery" pages (at the back of the magazine each month, what I go to first) is they give you exposure information, in case you want to go try it yourself. The above photo was taken during full moon, with 28 mm lens, 15-second exposure at ISO 800.

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Vince
28 mm lens.

That's meaningless unless one knows the area it is covering.

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eeek

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Vince
28 mm lens.

That's meaningless unless one knows the area it is covering.

Not sure what you're talking about. If you have a camera with 28mm lens and you set up at the location above and set your camera for ISO 800 and 15 seconds you should get a photo like the above. My camera can only set at ISO 400 so I would have to double the exposure time.

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Vince
Not sure what you're talking about.

Obviously.

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If you have a camera with 28mm lens and you set up at the location above and set your camera for ISO 800 and 15 seconds you should get a photo like the above.

No, that's not enough information Care to guess the focal length of the lens I used for this?

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eeek

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Vince
Not sure what you're talking about.

Obviously.

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If you have a camera with 28mm lens and you set up at the location above and set your camera for ISO 800 and 15 seconds you should get a photo like the above.

No, that's not enough information Care to guess the focal length of the lens I used for this?

I see you deleted two earlier posts of mine. Oh well.

Above I posted what was printed in Sky and Telescope's print edition.

Giving shooting data like focal length, ISO, exposure, etc. is something that many budding photographers like to know. Look through any photography magazine and you will see that data listed. For a shot like that, focal length can make a difference, because the wider the lens, the less pronounced the star streaks will be. Yes, their length is determined by the shutter speed, but the wider the lens, the smaller they will appear, and thus will appear less like streaks, and more like stars.

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eeek

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If you have a camera with 28mm lens and you set up at the location above and set your camera for ISO 800 and 15 seconds you should get a photo like the above.

No, that's not enough information Care to guess the focal length of the lens I used for this?

I'd guess in the range of 24-35mm - assuming of course that it's not cropped from a wider angle or stitched from multiple images!

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vdrummer

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eeek

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If you have a camera with 28mm lens and you set up at the location above and set your camera for ISO 800 and 15 seconds you should get a photo like the above.

No, that's not enough information Care to guess the focal length of the lens I used for this?

I'd guess in the range of 24-35mm - assuming of course that it's not cropped from a wider angle or stitched from multiple images!

Not even close. It's a single shot taken with a 90mm lens.

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eeek

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Vince
28 mm lens.

That's meaningless unless one knows the area it is covering.

Oh, I wouldn't say that's meaningless - 28mm is 28mm, and it's good for photographers to have a sense of that - i.e. how much area a 28mm lens covers.

For these kinds of images, it's also good to keep in mind that a 15 second shutter time is about the longest to hold stars as fixed points, and at longer than 30 seconds, stars start to blur and form star trails, (if of course your camera is on a fixed spot and isn't moving to track the stars).

I haven't been on here in a while- that's a cool photo. Too much noise reduction for my taste, but that's just because of the ISO 800 for 15 seconds on an entry DSLR, I'm sure. Also, I think when he said 28mm is meaningless perhaps he meant that he didn't know the area it was covering as in whether it was covering a compact camera sensor, 4/3s, APS-c, full-frame, medium format, etc. That picture was taken with a Canon XSI so it should have a 1.6 crop factor I believe. So that's roughly the equivalent of a 45mm lens on a 35mm film camera.



Edited 2 time(s). Last edit at 09/11/2010 07:24AM by dqniel.

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dqniel
I haven't been on here in a while- that's a cool photo. Too much noise reduction for my taste, but that's just because of the ISO 800 for 15 seconds on an entry DSLR, I'm sure. Also, I think when he said 28mm is meaningless perhaps he meant that he didn't know the area it was covering as in whether it was covering a compact camera sensor, 4/3s, APS-c, full-frame, medium format, etc. That picture was taken with a Canon XSI so it should have a 1.6 crop factor I believe. So that's roughly the equivalent of a 45mm lens on a 35mm film camera.

Thats what I figure, too. My compact digital camera is a Canon G6 and even though the actual lens is much smaller than an SLR's, the camera is equipped with old-fashioned settings like ISO and shutter speed (those dinky point-and-shoot cameras don't have that ability). I didn't want to clutter my original post with technical data about size of the CMOS sensor and all that, if you've been taking pictures longer than 10 years and are familiar with film cameras (which I still use, btw since digital cameras still lack in many ways) you'd know this stuff. Also FYI the photo caption says the photographer used a Canon EOS Rebel XSi DSLR. Only detail missing was the f-stop...

here's a full size 20mm image from similar spot:


and I figured out that if you head south to the other side of the river and scrunch down on the river bank near the water, you can exclude the roadside vehicles from your image - here's a full size 50mm image from there: