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3

My problem looks like it's between the glass elements. When the cement between lens elements fails, the problem is called Balsam separation (or just separation). Canada Balsam was used as an optical cement in very old lenses, but has been long been replaced with other materials in modern lenses. The problem is not "Schneideritis". Schneideritis ...


4

TL;DR: you need a 14.9 mm lens to cover your requirements The TL;DR is the "fish". Below is the "teaching one to fish" explanation... In general, other than fisheye lenses, cameras basically follow the pinhole projection model, meaning that the angle of rays entering the lens's aperture (which, for basic purposes such as this question, ...


-1

A tip of the hat to Bob McStevens who caught my math error. My apologies to all, especially Dale, the original poster – I can do better – will put on a dunce cap and stand in the corner. My error: I wanted to find the horizontal angle of view, object 2 ft. by 2 ft. as viewed from 2 ft. I created an imaginary triangle, apex origin the lens. The base is 2 ft. ...


-1

The format size of the 60d = 14.9mm by 22.33mm. You are asking for the angle of view needed to exactly image a 2ft. by 2ft. vista camera 2ft. distant. This works out to a diagonal angle of view of 35.26 degrees. Mount a lens with a focal length of 33.2mm and the angle of view realized will be 35.2 degrees.


4

A focal length equal to the short dimension of the sensor or film frame will produce an image that can (nominally) capture a square that is the same height and width as the distance from the camera. For example, 35mm film (or a "full frame" sensor) is 24mm high and a 24mm lens will fit a 1mx1m square at a distance of 1m. However because 35mm film ...


-1

The focal length needs to be the sensor height (so 24mm full-frame equivalent) in order to have something of height x in distance x cover the sensor.


1

The easiest way is put a zoom lens on your camera and figure out what focal length you need empirically. Since you don't say what your sensor size or camera model is, you'll need to do the maths yourself. Angle of view for your situation is about 2 * arctan(1/2) = 53°. From a Wikipedia article: angle of view = 2 * arctan(d/(2*f) Where: d = sensor size; f = ...


0

Try adaptive wide angle and lens filter in Photoshop, or in Lightroom, under geometry try upright/guided first though try everything. None of these are perfect but since you already have a lifetime experience looking at rooms you can eyeball it using a known object as reference. Probably not the most technical explanation, but it is going to get you to “good ...


3

It means exactly the same as f/. 1: is just an older syntax for denoting a ratio. You might also occasionally see 1/. Since the f-stop is essentially a ratio of focal length to entrance pupil diameter (the apparent size of the aperture when looking into the front of the lens), one of these notations is used to indicate, in this case, that at the 18mm end, ...


0

I removed the mount and soaked it in isopropyl alcohol. When I put the first few drops of alcohol on the bayonet, the gunk was already gone or dissolved. There was a lot of gunk in the stainless steel ring that holds the mount on. The lens now works perfectly on the camera.


4

Based on the information you provide, the suspected cause for this issue is higher than ususal friction in the lens' bayonet mount and in its aperture actuation mechanics. Possible reasons are: Damage, e.g. bent parts or corrosion Incorrect assembly Dirt has accumulated Whether repair is required or cleaning and lubricating will solve the issue is ...


2

Unless they are using distorting wide-angle lenses like fisheyes, wide angle shots will be done using so-called rectilinear lenses. They project everything in a single plane in the same manner. Architecture tends to be mostly flat, so that tends to render features on a wall pretty well. Now where does wide angle distortion come in? As you look less and ...


3

Most real estate photography is done with a rectilinear (ultra-)wide angle lenses. Rectilinear lenses keep straight lines straight, but distort features away from the central view. Wide angle rectilinear lenses are unkind to people away from the center of the image. Photoshop has a magical filter called Adaptive Wide Angle which will make objects (people) ...


4

Sorry for the bad news: Semi circular artifacts especially on a fast shutter speed are usually an early indication of shutter failure on the a7 III. Examples: Please inspect the edges of your shutter curtains for damage. The shutter edges should not be rough in any way. Often on the a7 III the shutters starts serrating which is reported as more sensor dust. ...


0

I believe the price depends on your location. I've tried to fix mine in the official Nikon service in Prague. It cost me around 100 euros and didn't work out :( But still it's cheaper than buy a new one.


1

The camera is broken. Professional repair is almost certainly more expensive than the cost of replacement with a used camera with similar capabilities. Professional repair is probably even more expensive than replacement with a new camera of similar ergonomics. It may be possible to repair the camera yourself depending on your tools, capabilities, and the ...


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