Lunch atop a (Springfield) skyscraper

Lunch atop a (Springfield) skyscraper
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19

The entrance pupil can not be any larger than the diameter of the front element, and that is what usually restricts the maximum aperture of telephoto zoom lenses - not the physical size of the aperture diaphragm. The physical size of the diaphragm is only part of what determines the maximum aperture, expressed as an f-number, of a lens. Magnification ...


12

Disclaimer: I am not a Canon shooter, nor have I owned Canon gear before. This appears to be a 300mm ƒ/2.8L USM (non IS) lens, produced from 1987 to 1999. The best collection of images, review, and information about this particular Canon lens I could find is: 300mm ƒ/2.8L at kenrockwell.com. Searching for this threw me off, because if you go to the Lens ...


10

A certain focal-length given a fixed sensor-size is expected to show the same field of view. That is, on the same camera, two lenses of the same focal-length will give the same field-of-view. There are two catches however: Focal-lengths are often rounded to conventional numbers. For example, a 35mm lens may be in fact a 34mm or 36mm, or even fractional. ...


10

Focal length is the distance between the lens and the sensor when the subject is in focus, not the distance to the subject. The term for the distance to the subject in focus is the focus distance. The zone which is in focus either side (front and back) of the subject is the depth of field. This varies with the aperture - depth of field increases as the ...


10

Why is the Depth of Field Preview button necessary? With the lens wide open, as it normally is before you take the shot, you can't tell how much depth of field you'll get in the photograph. When you press the button, the lens is stopped down to the selected aperture letting you see the shot as it will be recorded, depth of field and all. For both ...


9

The amount of light passed through the lens stays the same, the lens will still be a F/2.8 lens. Since the smaller sensor only crops out a different area from the illuminated circle, the exposure related properties of the image taking process will stay the same, regardless of the crop-factor.


8

The same light will pass through the lens regardless of the type of camera to which it is attached. Less of that total amount of light will land on the smaller sensor. But exposure, when discussed in terms of varying sensor/film sizes, is not about the total amount of light falling on the sensor. It is about field density, or the amount of light falling on ...


8

35mm to 55mm at f/5.6 to f/8.0 will get you great results with the EF-S 18-55mm STM. I really like SLR Gear's visual interactive graphs for checking out lens image quality at various focal lengths and aperture settings. SLR Gear Lab Test Results This is what a GREAT lens looks like, and below is what a CRAP lens looks like:


8

Lenses such as the AF-S Nikkor 50mm 1:1.8 G use a type of motor to move the focus elements known as a Silent Wave Motor (SWM). The technology was first developed by Canon, who refers to it as an UltraSonic Motor (USM). It has since been adopted by many lensmakers and is known by such monikers as Supersonic Wave Drive (SWD) - Olympus, Supersonic Drive Motor ...


6

They are very different lenses and will go nicely together in the same camera kit. We have an enormous amount of information on both types of lenses already on this site, so I'll just give you some keywords to search for to get you started in your research: In regards to the Tamron 16-300mm: Superzoom Variable aperture Zoom lens In regards to the ...


6

The quality of a modern zoom lens is outstanding considering all the manufacturing problems encountered. The maker would love nothing better than to keep the maximum aperture constant throughout the zoom. This is more easily said than done. The f-number is a ratio. Mathematically we divide the focal length by the working aperture diameter to compute the ...


6

Ok, looked at the work of Carlo Cafferini and Andreas Gursky you linked to, and did a bit of googling. Gurksy's work is mainly done with large format Linhof cameras, so whatever lens choice you go with, it's not going to look the same with an ASP-C format sensor that has no access to movements--at least not with a single shot. And Cafferini may be using ...


6

Japan was not the only country making cameras and lenses in the 1970's and 1980's but they had a huge market share. (they still do) Before World War II most good cameras were made in Germany. Japanese companies started making copies of German cameras in the late 1930's and by the time the war ended, these Japanese cameras were very good quality. In the ...


6

In lighting terms, a gel is a piece of thin, transparent, plasticky material in the color of your choosing. Rosco and LEE are perhaps the best known gel manufacturers, at least in the US. Gels come in large sheets that you cut down to fit your application. One 20"x24" sheet of a given color will probably last a lifetime if you're only using it in your gel ...


5

First, some terminology. On your 700D (or any of the 1.6x crop APS-C bodies), a 15mm and up is still just "wide angle". It's below 15mm that lenses become ultrawide. So if you want ultrawide, you need lenses that are around the 10-15mm focal length range. Wide angle on a 1.6x crop camera, typically means something in the 15-24mm range. Normal is around ...


5

Both Samsung and Edmund Optics use the name "Megapixel" or "MegaPixel" to describe lenses they sell for C-mount and CS-mount cameras, but in both cases the term is used like a brand name rather than a description of any technical aspect of the lens. There's also a perceptual megapixel concept developed by DxOMark to describe lens sharpness in a way that's ...


5

If two lenses have exactly the same focal length and exactly the same amount of distortion, then on a camera they have the exact same field of view. The exception is when you get to very wide angle lenses and some may be fisheye lenses while others are rectilinear. In that case, they will have different fields of view. You will find that you cannot buy ...


5

This reply to @Caleb's comment kept growing and growing into an off-topic answer. Maybe you still find it useful. After mounting the zoom ring gear, I'll attach a pinion gear to the stepper motor shaft to control the motion of the zoom ring. A linear zoom throw allows for smooth, consistent zooming that doesn't draw attention to itself. ...


5

why a lens's aperture only shuts to its specified stop when the shutter release is pressed, instead of staying static at that stop constantly That's because a closed aperture would reduce the amount of light coming to your eye. The viewfinder would be dim. Try the preview button on a lens with a wide open aperture like f1.4 and an aperture setting of ...


4

Frankly, you don't need a new lens, although there's certainly better glass to be had than what's in your bag. You need lighting gear. Portraits are basically made by the lighting, not so much the camera and lens (see the Strobist and Tangents). And the idea that better gear gets you a better keeper rate doesn't always hold true. Better sharpness, lower ...


4

As to why Japan was/is so successful a lens-making nation, the summary in this excellent thesis answers your question pretty well: http://www.academia.edu/891283/Rivalry_and_Cooperation_How_the_Japanese_Photography_Industry_Went_Global Edit: in a nutshell, the thesis linked here identifies that Japan benefitted from considerable market protection put in ...


4

If I've got a decent Box and have the means to protect the camera underwater, the lenses aren't IN the box how are they protected? Underwater housings completely contain both the body and the lens. It looks like the Nauticam setup has various lens housings that mate with the body housing, and you'll certainly need both parts.


4

The thin lens equation is 1/f = 1/do + 1/di, where f = focal length di = image distance = distance from lens to sensor do = object distance = distance from lens to subject. The focal length of a lens is defined by the thin lens equation, and it can be interpreted as a measure of the inverse strength of the lens. If you make a lens's optical surfaces more ...


4

A gel filter cut to a circle slightly larger than 39mm in diameter is what the holder is designed to hold. There should be a flap that opens up and lets you insert the filter material. You then close the flap back over the filter material to hold it in place.


3

Is there any way to get the stuff out from under my lens? I'm open to any ideas, even taking it apart. A non-invasive method should be the first thing you try. I'd wrap the camera in a couple layers of paper towel and then cover the towel-wrapped camera in (dry, uncooked) rice. Try to orient the camera so that gravity will keep the liquid off the lens ...


3

The lens and camera are probably "good enough", but they're ( of course ) not ideal. Unless you've a very large budget they're as good as you'll get. An ideal system would be much larger ( heavier and costlier ) and be more complex to use ( which is itself a handicap ! ). Better the equipment you know than something you don't. Given that wildlife shots ...


3

Your budget is too low to upgrade. You really only have two choices at that price point, and that would be another 18-55 kit lens, or the EF 50mm f/1.8 II. Maybe the updated EF 50 f/1.8 STM. (Yongnuo's 35mm f/2 and 50/1.8 are also in the budget, but, well, you get what you pay for). And a 50/1.8 is a distinctly different type of lens, and cannot do ...


3

Generally speaking for portrait and event photography I would recommend getting rid of everything but the 100mm macro. Pickup a 24-70mm f/2.8 and 70-200mm f/2.8. Beyond a general recommendation I can't tell you much more. What I would recommend is bringing your images into software such as Adobe Lightroom that allows you to see the percentage of images ...


3

The problem has nothing to do with the image not being entirely focus but more of that it is soft. At f/4.0, there is a significant softness that the lens has. When you are looking at photo 100%, this softness becomes more pronounced. Details just become harder to capture for such a small portion of the image. Remember that when you are looking through the ...


3

So far I was really impressed by the 10mm ones, however the ones with at least decent aperture comes without Image Stabilization. I also looked to the 15mm ones, with IS. Ultra wide angle is a really desirable thing for me but I would also like to protect my pictures from blurring since I am not a fan of using a tripod. A longstanding rule of thumb ...



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