I Dare You!

by peter_budo

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0

Assuming that: The focal length has been recorded in the file metadata You are running a Unix-like OS such as Linux or OS X You have installed the exif command line tool Run this on the command line: exif /path/to/your/photos/* | grep "Focal Length [^A-Za-z]*|" | awk -F "|" '{print $2}' | awk '{print $1}' | sort | uniq -c | sort -nr Example output:


3

Another option that would work for some purposes (i.e. a single still image) is to stitch multiple pictures together. Since you mention a GoPro, I'm guessing this might not be what you have in mind, but it's one possible solution to the question as stated, so it should probably be included...


2

A width of 12 units in a distance of 3 units corresponds to a horizontal angle of view of 127°. For a full-frame digital SLR with a sensor width of 36 mm, the corresponding focal length is 9 mm. You may want to consider using a fisheye lens, which typically offers a 180° diagonal angle of view or even a 180° circular fisheye image.


0

A DSLR would need aproximatly 5mm focal length lens to achieve this. Based on the "Dimensional Field of View Calculator" a 1.5x crop sensor camera would need a lens with about a 6mm focal length. A "full frame" camera would need a lens with a 9mm focal length.


1

The crop-factor is specified as 9.42. So you have a 4 x 9.42 = 38mm equivalent lens. Apparently, that "Type 1/4 sensor" has to be taken with a grain of salt. The diagonal seems to be 0.18", closer to 1/5.


1

It does not affect the focal length or angle of view or anything else. That "designed for crop sensor" statement means that it will be smaller (lighter, cheaper) and produce a smaller image circle that won't fully cover a full-frame sensor. So if you are able to mount it on a full-frame you will see severe vignetting.


2

The advertised focal length is the actual focal length of the lens and not the Full frame equivalent focal length. The focal lengths are reported like this as the focal length of a lens is a physical property of the lens that is not changed by the size of the surface onto which it projects an image.


0

I would avoid picking up a new zoom, but rather look at some fast primes. If you can get a fairly wide angle prime with a large aperture (like a 35mm f1.4 - my Sigma Art lens is my favorite!) you will have a much easier time shooting indoors and I think you'd find that the images are of better quality.


5

I think the problem here is that you assume focal length is all (or the most important factor) you need to look at when choosing a new lens. It isn't. Your other problem is assuming that a lens is going to solve your problems. It may not. All things being equal, getting a walkaround superzoom when you already have a "twin kit" of a wide-to-normal/short ...


9

Your edit adds some clarification: you have trouble shooting indoors. Typically when shooting indoors and fighting tight spots means you need a wider lens. If the 18-55 isn't wide enough, then the 18-140 is going to be no different -- they are both 18 mm at the wide end. In other words, the 18-140 won't help that situation; the 16-85 is a bit wider, so that ...


1

I'm guessing from your mention of the 18-140mm that you're using Nikon gear. The 16-85mm should make an excellent "everyday" lens that covers many situations, and offer a useful upgrade from the 18-55mm kit lens. It should be wide enough for indoor work, landscapes etc., and long enough so you won't be wanting to fit your 55-300 every time you need a ...


2

At the moment, this question reads to me like a case of Gear Acquisition Syndrome: the first thing to do is to work out why you want a new lens, and then pick a lens which lets you do that. Buying a lens for the sake of buying a lens has a high risk of just throwing money away. I'd suggest sitting down, working out how your current equipment is holding you ...


1

It does look a bit like a tilt-shift lens, but I wouldn't be 100% positive. I'd say it was taken with a 50mm/<1.2 lens on a full-frame sensor. With a 35mm and an APS-C sensor you would need to be closer to the subject in order to achieve that field of depth. A flash might have been used, but I think you do not need any for that kind of shot.


7

I'm going to take a wildass blind guess, but doing an image search on Google which led to WrongRob's Instagram and then his website, it looks like he shoots with a Leica M, which has a full frame sensor in it. So my guess would be that the thin depth of field may have been created with a Noctilux 50mm f/0.95 lens. Whatever apertures he's using, if he's ...


-2

look at this review which lists point and shoot cameras with wide-angle lenses http://www.bhphotovideo.com/find/newsLetter/Wide-Angle-Imaging.jsp


1

Focusing doesn't require changing the focal length of a lens, it changes the distance of (the center of) the lens to the sensor or film.


0

If you want shallow depth of field, you need 3 things: wide aperture, long focal length, large sensor (eg. full 35mm frame or 120/220 film). Out of those, only aperture can be varied freely, because both sensor size and focal length show on angle of view, changing your composition. Longer focal length and larger sensor somewhat cancel each other. This sadly ...


2

No the lens equation 1/u + 1/v = 1/f is not useful in this circumstance, as the image distance v (labelled S2 in the diagram above) is unknown, and the only way to find that distance would be to cut the camera in half and measure it. Even if you did that (bearing in mind it changes as the lens focuses, so make sure you focus before cutting it in half) it's ...


4

The lens used would have a reasonably large aperture (low F number). This gives the effect of a relatively narrow depth of field and also allows more light to get to the sensor, making it easier to capture a correctly exposed image. The focal length used would be in the 'normal' range (somewhere around 50mm for Full Frame, or 30mm on APS-C), as opposed to ...


3

You should use the actual focal length of the lens in question. When you include the sensor size into the equation FOV = 2 arctan(SensorSize/2f), you have already included the crop factor into your calculation. That is because the so called crop factor is really nothing more than describing what field of view, in terms of a lens of a given focal length for ...


4

Let's consider a simple pinhole camera, taking a picture of a uniformly illuminated wall. Because this is a uniformly illuminated wall, each of these rays represents the same amount of light. There are nine rays hitting the film. Now if we move the film back, we get a narrower field of view. This corresponds to the longer focal length of your 105mm lens. ...


1

Crop factor exists simply to convert real focal lengths to the focal length that would give a certain field of view on the "reference" format, 35mm film. So, yes, crop factor affects field of view, by definition. So, for your purposes, there are two ways of looking at this. If you have the spec with the real focal length, use the real focal length and ...


13

"Therefore lens 2 has a larger maximum aperture than lens 1 and therefore capability to allow more light. This is where your understanding is not quite right. The physical size of the aperture is indeed larger in the longer lens, but it does not allow in more light, because the longer focal length means that the field of view is narrower. This means ...


0

Another member of this Exchange (jdlugosz) recently posted this link as a comment to a question about Camera Phone Photography - http://dofsimulator.net/en/ It has a depth of field calculator that may help determine what you are looking for


0

Yes, the crop factor definitely affects the field of view, and applying the effective focal length should give you the result you need.


0

The "crop factor" of sensors smaller than full frame is never respected in the specs of lenses. A 50mm EF-S lens has the same focal length as a 50mm EF lens, and will produce the same field-of-view on the same camera.


5

I'm aware that actual focal length of a lens on APS-C cameras is longer than what is written on the lens. Sorry to say this, but whoever told you that was wrong. The actual focal length of a lens on an APS-C camera is exactly1 what is written on the lens. What you're probably confused about is the fact that the field of view you get from mounting a 50mm ...


0

I would go with ultra-cheap Tamron 70-300 OS or Nikon 70-300VR. I think they're both of equal design. At least that's word on street that they were from same specifications. Both are great for DX cams. Also, the 55-300, I believe, is good. Lost track of DX lens lineup. Just get VR in whichever lens because handholding without blur is nearly impossibly at ...



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