Discussion Topic |
|
This thread has been locked |
ydpl8s
Trad climber
Santa Monica, California
|
|
|
Nov 27, 2012 - 12:56pm PT
|
I was on top of La Plata Peak in Co. with Gary and Craig Koontz. Craig had carried a 3000 mm lens up there (lot of extra weight for doing the Ellingwood Ridge). He took a picture of Uncompahgre Peak (in the San Juans) from the top of La Plata (in the Collegiates) that filled about a 1/3 of the lens (I'm guessing between 80 to 100 miles as the crow flies). Between the wind and the "heat waves" obscuring the image, he had to take about 30 pictures to get a good one.
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
|
Nov 27, 2012 - 01:05pm PT
|
Who makes a 3000mm lens?
|
|
ydpl8s
Trad climber
Santa Monica, California
|
|
|
Nov 27, 2012 - 01:12pm PT
|
Canon, for one.
|
|
Jerry Dodrill
climber
Sebastopol
|
|
|
Nov 27, 2012 - 01:13pm PT
|
The thing is, aside from having a sacred rock in it, its not really that interesting of an image.
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
|
Nov 27, 2012 - 01:18pm PT
|
Isn't that a 300? :-)
|
|
Mike Bolte
Trad climber
Planet Earth
|
|
|
Nov 27, 2012 - 01:38pm PT
|
Some folks referred to this image. It is a mosaic of images taken on December 16, 1931 from Lick Observatory by Fred Chappell. This was a day after a storm had rolled through washing out the dust and haze looking across the central valley. The photographs were also taken on plates that were treated with "kryptocyanin" and filtered to only allow what they called infrared radiation then, but is probably around 900nm wavelength. This helped further to cut through the haze and to minimize atmospheric distortion.
The images were taken with a special camera with a 6-cm diameter lens with 1.5m focal length. This is one of the cameras that were built for photographing the area around the sun during a total solar eclipse to measure the deflection of starlight by the mass of the sun and test Einstein's theory of General Relativity.
There is a print up at Lick Observatory that is around 2.5m long and is really fun to stare at. There are at least three peaks misidentified in that big print. I think the IDs in the above jpg are correct.
Ed, Clint - smart and fun stuff you guys have put up on this thread!
EDIT: the canon lense up there is the 300mm f/4
EDIT 2: if anyone wants a larger version this photo, send me an e-mail via ST and I'll send you a 10k x 3k version
|
|
ydpl8s
Trad climber
Santa Monica, California
|
|
|
Nov 27, 2012 - 01:52pm PT
|
Reilly, I must admit I'm kind of a neophyte and might be getting focal length and focal distance mixed up. All I know is that lens he had was huge and added considerable weight to his pack, he called it a 3000, he mounted the lens on the tripod and then screwed the camera on to it.
|
|
Ksolem
Trad climber
Monrovia, California
|
|
|
Nov 27, 2012 - 02:33pm PT
|
I have a novice question about forshortening caused by telephoto lenses. Is the effect linear, or is it applied over a curve of some sort? Does f-stop alter the effect or just change the depth of field?
I am no expert, and out of respect to the photographer am not going to say anything about the reality of the image. What I am curious about and hope one of the experts can explain is why the forshortening in the picture appears to be greater in the distance between the siloh and the dome than between the dome and the distant peaks. Also the lighting of the dome and mountains looks so much different than the foreground lighting where the direction of the sun is very apparent. The background lighting looks ambient almost like a different time of day.
It is a very striking image, but I cannot get comfortable looking at it.
|
|
Jerry Dodrill
climber
Sebastopol
|
|
|
Nov 27, 2012 - 03:12pm PT
|
Ed, My quick analysis concludes that the best bet for a moonrise is January 26 from somewhere near the Turlock Municipal Airport.
|
|
Chewybacca
Trad climber
Montana, Whitefish
|
|
|
Nov 27, 2012 - 04:40pm PT
|
I've never heard of a 3,000 mm lens but here is a 5,200 m f/14 Canon lens. At 220 lbs I doubt I would want to hump it up any peaks. http://www.popphoto.com/gallery/9-unbelievable-camera-lenses-actually-exist?image=4
9 Unbelievable Camera Lenses That Actually Exist
These rare lenses come with unbelievable specs and spectacular price tags.
By Theano Nikitas on July 8, 2010
< Prev
4 of 9
Next >
Related Tags:
How-To
Advertisement
Close ad
Canon 5200mm F/14 Mirror Lens
Using a group of mirrors and a housing that's almost big enough to use as a coffin, Canon was able to stretch the focal-length on this SLR-specific lens to 5,150mm. Just how long does that make it? The original Canon info sheet claims its best used for photographing obects 18 to 32 miles away. In fact, in order for it tobe able to focus at all, your subject will have to be at least 120 meters (~394 feet) away.
Even with the mirrors to help keep things compact (at least compared to the previously mentioned 1,700mm Zeiss), the total package still weighs 220-pounds without the solid metal stand on which it's intended to sit. The rest of the measurements are just as impressive, including its 20-inch height, 24-inch width and its massive 75.6-inch length. There's currently a youtube video of it in action from a few months ago when one went up on ebay and sold for almost $50,000.
NEXT: Carl Zeiss' 50mm Planar f/0.70
;
The 1700m f/4 lens on that site is also massive at 564 lbs.
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
|
Nov 27, 2012 - 04:48pm PT
|
Chewy, is that a full-frame or DX lens? ;-)
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
|
Nov 27, 2012 - 05:12pm PT
|
You can read up on DOF and hyperfocal distance here:
Hyperfocal Distance
There are four pages to this tutorial and on the fourth page you can get a
link to an iPhone app!
|
|
Reilly
Mountain climber
The Other Monrovia- CA
|
|
|
Nov 27, 2012 - 05:47pm PT
|
The photog used a 400mm. He was 1,5 mile from the silo.
A 400mm at f/11 would have a near focus limit of 1353',
........................................ far focus limit of Infinity
and ................... a hyperfocus distance of 1856'
If he shot at f/8 the near focus would be 1331'
and the hyperfocus distance would be ...2625'
with the far focus still at INFINITY!
It's still bogus. ;-)
|
|
climbski2
Mountain climber
Anchorage AK, Reno NV
|
|
|
Nov 27, 2012 - 05:48pm PT
|
When the foreground is over a half mile away it's not that hard. The exact location is available on google and the photo is attached on google earth.
|
|
Banquo
climber
Amerricka
|
|
|
Nov 27, 2012 - 06:07pm PT
|
Here is the peakfinder view from the silo.
|
|
Ed Hartouni
Trad climber
Livermore, CA
|
|
|
Nov 28, 2012 - 12:12am PT
|
peakfinder is cool, though I still don't have all of the peaks id'd, the one I had as Dana is Mt. Hoffman...
Lots of things are going on in the image that make it difficult to reconcile with "your gut"
interestingly, one of those things is that the Earth is a sphere, and it dips down out past your horizon... that skews a lot of perspectives and makes things difficult to place...
with a 500mm lens the entire view across a 35mm piece of film is 35/500 = 0.07 rad = 4.01º
at 4000 dpi on the film gives you 5512 pixels across that 35mm, Half Dome from the image position above is something like 0.16º or 220 pixels...
given that a standard STForum image is 800 pixels across, a crop with Half Dome centered on the image would have the middle quarter of the image filled up with Half Dome... and ±2º around that to view the Sierra Nevada, since the crest is only about 1.5º high you get everything in that scene, to the crest, and all the peaks on a 10 mile section subtended by the image plane.
I count 13 peaks in that area, 5 of them at about 12,000' elevation.
Getting the Moon in that picture, at 0.5º across would be like 670 pixels, basically the entire crop for STForum image...
|
|
john hansen
climber
|
|
|
Topic Author's Reply - Nov 28, 2012 - 01:05am PT
|
This is a cool thread, I have no doubt the photos are real. I drove around looking for the silo a few times but the central vally is not real good for photo;s, unless they are after a storm.
Jerry and Ed.,,..
The dream team, the moon and the sun...
|
|
Banquo
climber
Amerricka
|
|
|
Nov 30, 2012 - 03:34pm PT
|
I decided to analyze the photo referred to in the original post to see if it had been photoshopped.
The EXIF data from the original image records that the camera was an Olympus E-3 and that the focal length was 400mm (the photographer also states it was a 400mm lens). The EXIF also says that the image was processed using Silkypix software which is RAW image processing software. Being captured in RAW rather than JPEG format and processed in the RAW state may explain why it doesn’t look like the typical JPEG. All digital cameras have built in software that converts the image from RAW to JPEG format. The software built into cameras usually isn’t all that great. The image also has an embedded color profile.
Olympus E-3 has:
18.00 × 13.50 mm (0.7087 x 0.5315 inch) sensor
3648 × 2736 pixels (10.1 megapixels)
Aspect 4:3
The width of the field of view is 2arctan(9mm/400mm) or 2.57 degrees. The height of the field of view is 1.93 degrees. If the image hasn’t been cropped and ignoring small angle errors, in the original 1600x1200 pixel image, 1 degree is about 620 pixels. I believe the error in estimating angles this way is about 0.1% and much smaller than my other errors. I drew lines on the image at 1/10th degree intervals from which I find the left eave of the grain elevator is about 0.94 degrees left of image center and the peak of the shed roof is about 0.62 degrees right of image center.
TOPO! Tells me that the top of Half Dome is 65.95 miles from the elevator on a bearing of 77.59 degrees (clockwise from north). In the reverse direction, the bearing from Half Dome to the elevator is 77.59+180=257.59 degrees.
I copied some images from Google satellite and made a composite so I could lay things out. I drew a line from the left eave of the elevator roof on a bearing of 77.59-0.94 degrees and one from the peak of the shed roof at a bearing of 77.59+0.62 degrees. I extended these lines until they intersected. From the intersection I added a third line at a bearing of 77.59 degrees to represent image center and the summit of Half Dome.
The lines intersect on the canal which is short of Hall Road where the photographer says he took the photo. If I extend the line it intersects Hall Road 0.65 miles south of E. Keyes Road. The photographer says he took the photo on Hall Road 0.65 miles south of E. Keyes Road. The fact that my projection came up a little short of Hall Road tells me that he cropped the image a bit, probably to put Half Dome in the image center or otherwise make it look better. Most likely it was cropped to level the image if the camera wasn't level.
The intersection of my lines is 1.36 miles from the elevator while Hall Road is 1.57 miles which suggests he cropped the photo about 13.3%. The camera sensor is 3648 pixels wide so if he reduced by half he should get 1824 pixel width. The image is 1600 wide which is a reduction of 12.3% from 1824 pixels.
So, it seems clear to me that the image was taken from the exact spot he says it was taken from with the camera and lens he reports. I believe it has been cropped 12 or 13%. The image has also been processed for sharpness which has left some odd defects when inspected at full resolution. It doesn’t look like what the eye or a telescope sees because cameras don’t see the same way the human eye does and it has been enhanced a bit.
Also, the 2000 foot high NW face of Half Dome should be about arctan(2000/65.95*5280)=0.33 degrees high in the image which it appears to be although you can’t see the bottom of the face. Also, the grid scale is probably off due to the cropping.
Edit addition:
The dirt berm in the foreground is probably the canal. The dirt ramp to the right can be seen in the satellite image.
|
|
matty
Trad climber
under the sea
|
|
|
Nov 30, 2012 - 03:59pm PT
|
^^^nice work!
but they still wont believe you...
HATERS GUNNA HATE!!!
|
|
|
SuperTopo on the Web
|
Let us know!