Google Earth's cameras are like movie cameras. That is they take individual pictures except at a relatively slow rate. Then they stitch them together. This is two pictures stitched together and the seam is where the car's wheels are. The buildings didn't move but the car did so it is in both pictures.
Considering the cost of weddings and how long some marriages last, I have long proposed the following. The wedding should be simple and cost no more than $1,000. If the couple is still married 10 years later, then you have the big party.
When photography was in its early modern era, they developed what I call the exposure teeter totter. (Not exposure triangle as once you put film in the camera you weren’t likely to replace it.) The idea was to simplify aperture area vs shutter speed so that each changed by a factor of two. To simplify the system and make it universal, they non-dimensionalized the aperture by dividing the focal length by the aperture diameter. Since the area of the aperture was proportional to the square of the diameter, the increments of aperture changed by the square root of two. This resulted in typical apertures of 1.4, 2.0, 2.8, 4.0, 5.6, 8, etc). The system was universal. When I picked up my light meter, I only cared about the lens’s f stop. It didn’t matter what lens I picked up.
However, when you do the math for typical lenses, you learn the following.
Lens f Stop Aperture Diameter Aperture Area
35mm Lens f4.0 8.75mm 60 sq mm
50mm Lens f4.0 12.5mm 123 sq mm
70mm Lens f4.0 17.5mm 240 sq mm
100mm Lens f4.0 25mm 490 sq mm
So my question is simply this. What is the physics that requires a 35mm lens with a 60 sq mm aperture to let in the same amount of light as a 100mm lens with a 490 sq mm aperture?
As I was using my new laptop, I noticed a tiny black dot moving across the screen. How unusual. I suddenly realized there was a tiny insect on the inside of the glass. Without thinking, I pressed on the glass and squished it permanently in position. I now and forever more have a bug in my computer.
Very interesting. Usually you use heat to loosen something tightly screwed on. But then again, using a propane torch probably wouldn't do the lens much good.
If you watch the video, he said that while the Nikon might be a better camera, he chose the Canon because it had a "silent" shutter mode so that he would be less intrusive.
Thank you very much, yes that answers the question. It says US 4 etc.
I have a geeky focal length question with respect to a simple meniscus lens. The classic focal length equation states that when the subject is at infinity, focal length = image distance. I have a 1940s Kodak Bantam camera with a simple meniscus lens. The lens states that it has a 47mm focal length with a maximum f stop of f4.5. The lens appears to have a diameter of about 10mm so multiplying it gives me a focal length of about 45mm. If I measure the actual distance from the lens to the plane of the film I also get about 47mm. So within reasonable error (on my part) they all box.
I also have a 1920s Kodak 1A folding bellows camera with a simple meniscus lens. I have seen it listed one place with a 65mm focal length and another with a 133 mm focal length. The camera lens does not state the focal length. Measuring the distance from the lens to the plane of the film I get about 130 mm. However the maximum f stop is f4 while the lens appears to have a diameter of about 16mm. This results in a 64mm focal length. (Close enough to 65mm.) Does this actually mean that the extra ~68mm is a 2x multiplier and similar to an extension tube. If so, then does the camera have a 65mm focal length and a 133mm effective focal length?
The film frame is listed as 65mm X 110mm. This would this produce an average “crop factor” of .35 resulting in a net 35mm camera focal length of 47mm?
I know that the lens’s aperture determines the viewing angle and the amount of light that passes through the lens plus is used for the calculation called F stop. However, does the size of the objective lens also affect the amount of light through the lens. In other words, would two lenses of the same focal length and aperture pass the same amount of light if one’s objective lens was larger than the other? Or, is the objective lens's size a function of the size of the largest aperture?
This is also true for boats.
I found Rome to be very disappointing. So much of it is broken or missing. Their stadium is in horrible condition. I have no idea how they can have football games there. Also the colossal statue said to be just outside of it is missing. The Arch of Constantine is very worn. Trajan’s column is full if graffiti that is carved into it. And don’t get me started on the Forum. It’s a total disaster. Even the Pantheon has a hole in the roof.
I can't comment on the lens as I have a FZ1000 which works great for my needs. We took that trip one month ago and had a terrific time. If you are taking Viking's tours (as with most tours) you won't have a lot of time at any given spot to take your pictures. Also expect the Hermitage to be a zoo. (Albeit a magnificent zoo.)
We bought regular tickets on the internet prior to our trip. That allowed us to walk right in rather than wait in a long line at the ticket window. We then opted for the "audio vox" for our tour. Yes there are crowds but I was able to take the pictures I wanted without a problem. You might get a little more information with a special tour but you move on their schedule. On your own you can move on your schedule. Yes, the Sistine Chapel is a zoo and pictures are not allowed. On the other hand it is not as large as you might think and dark. Unless you are bringing an ultra wide lens, tripod, and lights, you might be disappointed in the results. A less expensive option is buy a book.
I thought "The rain in Spain stays mainly in the plain!"