Questions tagged [lens]

A photographic lens is used to focus the light onto film or a digital sensor. Many cameras have interchangeable lens systems, allowing the photographer to choose the type of lens to use.

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3 answers
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Why do some lenses have a rounded front element?

I've noticed that some lenses, mainly wide-angle or fisheye (e.g. Samyang 14mm f/2.8, or Nikkor 8-15mm fisheye) have a rounded front element. Which is the reason for it? It's of course limiting in ...
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What should I consider when shopping for a second lens (after the kit)?

I have a Nikon D7500 with the 18-140 mm zoom lens, and I've been shooting for a couple of years, although I still consider myself to be a beginner photographer (check out my work). I see myself ...
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How can a fixed-focus lens have a focus range of 0.5 meters to infinity?

I have a Mavic Air 1 drone and I was wondering how the camera of this drone can have a shooting range as large as 0.5 meters to infinity with a fixed focus? Mavic Air 1 camera specs: Parameter Value ...
3 votes
2 answers
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What is the optimal pixel count on a cropped sensor for Canon 100mm macro USM lens?

While choosing used camera to buy, I was checking some combinations of camera bodies with Canon 100mm macro USM lens at DXOMARK and noticed that sharpness (in perceived megapixels) looks very strange. ...
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1 answer
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What determines the image circle diameter?

Anywhere in the web it's stated that the image circle diameter depends on the lens design. I'm curious to understand it a bit better. Let's start with basics. Let's consider a single thin lens ...
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Canon ETTL-II and the Canon 50mm f1.8 STM lens

I read somewhere that the Canon ETTL-II system cannot read subject distance from Canon's EF 50mm f/1.8 II lens. Is this the same for Canon's more recent 50mm f/1.8 STM lens?
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1 answer
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Calculating DOF for custom optics

I was trying to get my head around the DOF for my custom optics design and sadly it seems I end up with strange situation that the Near DOF value is larger than the far one making my DOF value ...
3 votes
1 answer
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TTArtisan 25mm f2 lens focus ring adjustment

The lens: https://www.ttartisan.com/?list_10/152.html I bought this lens now twice for my Fuji X-E1, and both lenses had identical infinity focus issue. Infinity mark is not focussed, I have to move ...
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Why binoculars have magnification number, but lenses don't [duplicate]

I got into birding recently and got a pair of 10x42 binoculars and got a camera with a crop ratio of 1.6 and a 100-400mm (focal length) lens. With binoculars and spotting scopes everything seems easy -...
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How can I find a lens locking screw if I have lost the original one?

I have an industrial camera with a C-mount lens, like this one: (Source of image, last accessed 2022.11.02.) You can see a tiny screw on the top of the picture. It is used to lock the focus ring or ...
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3 answers
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Understanding Entrance Pupil

let's consider a simple lens without diaphragm. For a lens like this, the book Science for Curious Photographer states that: The important fact is that the illumination of the image is proportional ...
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Nikon lens have weird sound when autofocusing after dropping

Today I dropped my Nikon D50 with AF-S 35mm from about 0.5m high to wooden floor. Lens landed first. Everything seems to be fine except that the lens is making disquieting sounds when autofocusing. It'...
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3 answers
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How does an afocal lens produce an image on a screen?

I'm really confused about it. If such a lens is necessarily focused at infinity and does not have a plan of focus, then, does it mean it can produce a clear picture on a screen, no matter how close it ...
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1 answer
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Calibrate Argus C3 focus

As a personal project I bought a broken Argus C3 on eBay, and managed to completely clean and fix it, however it involved taking the lens apart since there was dead insects and dirt inbetween the ...
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Do photographic lens show virtual image if the subject distance is less than focal length?

A convex thin lens produces a real inverted image if the subject distance from the lens is higher than the focal lens. If it is lower, the image will be virtual. Of course a virtual image appears on ...
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1 answer
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Can a broken film sprocket mechanism on a Minolta 7000 AF be fixed?

My granddaughter was given an old Minolta 7000 AF with a Sigma Zoom 28-80 lens. The film sprocket mechanism doesn't work. Is this fixable? Or would the lens be compatible with a new Minolta X-700?
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1 answer
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How does the Elgeet 1/2" f2.3 lens work on the Keystone 8mm K25 Capri movie camera

Picked up a Double 8mm Camera "Keystone 8mm K25 Capri" which came with a single lens Labeled Keystone Elgeet 1/2" f2.3. On this lens it has a single control ring for f-stop. But it also ...
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I want to match same field of view with different focal length is there any formula? [duplicate]

Trying to get any hard formula so according to that calculation for different focal length i place object accordingly. Eg.
3 votes
0 answers
140 views

How do these modern multi-lens/multi-sensor smartphones work?

My last smartphone just had one front lens, so I could understand. My current phone has three front lenses (and three sensors, too, I guess), so I was a bit surprised, that I had zero control over the ...
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Why does Nikon Micro-Nikkor 55mm f/3.5 pre-AI show 1:1 markings when it can only get to 1:2?

I own this (mechanically and optically superb) lens since quite some time and was wondering why the blue marks that say 1:1, 1:1.5 and 1:2 don't actually correspond to the reproduction ratio that the ...
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Canon 85mm front glass spots problem

I have canon 85mm f1.8 lens but the front glass got a lot of tiny scratches and it's affecting the sharpness. Can it be repaired or replaced? How much does it cost?
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can 70-200mm lens on Sony a7 iii full frame camera be used in APSC mode instead of 100-400mm lens?

I am a newbie to photography and I am planning to buy a sony a7 iii as my first camera and have safaris in Rwanda in the pipeline and also other tiger safaris in India. I am thinking to buy a 70-200mm ...
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Is an M12 lens inferior to other lenses (C-mount) for producing high picture quality?

I have always used C-mount lenses from manufacturers like Kowa. I have been interested in M12 lenses lately, but since they are so small I just assumed the picture quality produced must not be as ...
16 votes
2 answers
2k views

Why do photos with different settings produce different spots? [duplicate]

I have an issue with my Nikon D3500 camera which I do not understand. I can show it best using two photos I took with different settings. The lens I use is a kit lens which ranges from 18 to 105 mm. ...
1 vote
1 answer
138 views

What lens would suit an A4 large format camera

I'm planning on building a scanner camera. The principle of which is simple: everything's built like a large format camera, except the film is a simple scanner controlled by computer. Now, building ...
3 votes
1 answer
129 views

What does it mean for a lens to be "cold"?

Sometimes in lens reviews I read that a lens has a "cold" look, as opposed I suppose to a "warm" lens. So, for example, Voigtlanders are often described as "cold" lenses. ...
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1 answer
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Is this MTF chart real?

I stumbled upon an MTF chart, which looks wrong. It's for Kowa LM5NCL lens: https://www.kowa-lenses.com/en/lm5ncl-mp-industrial-lens-c-mount?number=10097. Here is the chart in question: It shows the ...
2 votes
2 answers
131 views

What type of mount is this?

I bought this lens - on it it says: FUJINON-TV Z 1:1.9/10-140 FUJI PHOTO OPTICAL CO. I am trying to identify the mount and see if I could mount it on any camera system I have (Olympus Pen F, Sony NEX, ...
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Olympus M.Zuiko 100-400mm lens on a Panasonic GH4?

The lens in consideration is the Olympus M.Zuiko Digital ED 100-400mm f/5-6.3 IS Lens for a Panasonic GH4 which I already own. I have reviewed the x lens, y camera question/answer, but looks like ...
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1 answer
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Camera not working while shooting long distance

I have a nikon 3200 and lately I have observed that it does not allow me to take any photos if the lens is not zoomed. It doesnt even focus or take any picture even when I click the button. I checked ...
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1 answer
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Focus ring on Canon 18-200mm stuck

I am very new to photography and my 18-200mm lens by canon has gone broken. The focus ring seems to be stuck. It nearly does not move at all when there is no zoom and it moves roughly when zoomed out. ...
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1 answer
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Is this lens compatible? [duplicate]

Will a Vivitar 75-205mm 1:3.8 MC Lens fit my Canon Rebel t7i or do I need some type of connector?
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2 answers
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How to carry gear while wearing a harness? (wedding photography)

Wondering if anyone could help. I'm getting into wedding photography and am trying to figure out how I want to carry my gear for the day. I want to get either a dual or single leather harness (I'm ...
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0 votes
0 answers
128 views

Recreate this lens specification

So my Samsung note 10 details say this about their telephoto lens 12 MP, f/2.1, 52mm (telephoto), 1/3.6", 1.0µm, PDAF, OIS, 2x optical zoom. I tried using it to see through my peephole which has ...
1 vote
2 answers
101 views

Can my Canon EOS 5D Classic work with a Vivitar lens?

Will a Vivitar 75-205mm 1:3.8 lens work with the Canon EOS 5D Classic? What mount lenses can I use for my camera?
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2 answers
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Putting telephoto lens on top of an OEM lens?

I want to use something like a Wyze Cam v3. Many users have removed the original lens and put on a telephoto lens. I dont want to remove the OEM lens. Can I put a telephoto lens on top of the original?...
1 vote
2 answers
639 views

Easy tool to correct geometry of photographed document

I know there is already an answer to this question on either photo.SE or something about imaging SE but after trying gazillions of search terms and word combinations until exasperation (and of course ...
3 votes
6 answers
522 views

How can I ensure that a lens is pointing absolutely vertically downwards?

My uncle makes models of all sorts of things. To help him, he uses his camera(s) as scanners by photographing his various bits, and then performing further CAD on the resultant images. These models ...
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1 vote
0 answers
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Beginning photographer wants advice on how to shoot Alaskan Cruise glaciers and wildlife [closed]

I have a Rebel T3i with Canon zoom lens EF-S 18-55 mm lens 1:3.5-5.6 IS ll and a Canon EF-S55-250 mm f/4-5.6 IS STM lens. I would appreciate any advice on how to get clear photos and video on our ...
7 votes
4 answers
342 views

What can I do with a broken lens?

I had a little accident with my camera the other day: please don't let your camera on the roof of your car and then drive your car. Now my lens is broken. It's an old Yashica lens, it comes from the ...
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1 answer
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What is this mystery Vivitar lens mount?

I was given a box of old lenses by a friend, and came across only one that's different. It's a Vivitar 135mm f/2.8 auto lens. I'm not familiar with the lens mount. After comparing both Nikon ...
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2 answers
215 views

Buzzing Noise and error 01 canon camera

Hi I have a canon rebel T3 have a canon 75-300 mm lens. When i lock the lens in and turn on it starts to make a buzzing noise and I get error 01 when I try to take a picture. I try to take pictures ...
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4 answers
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Are most (if not all) lenses' focal length described as the 35mm equivalent? [duplicate]

2 thoughts made me ask this question: Different lens looks different on the different-sized sensor and has a different 35mm equivalent Many normal and wide-angle lenses' optical center is not ...
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1 answer
162 views

Screw on teleconverter lens

I have a D5100 with a Sigma 50-200 but I also have a a 2x and 3x teleconverter lens. The problem is that the teleconverters are screw on. Is there an adapter for this?
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2 answers
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Tamron SP 500mm mirror lens changing aperture and DOF

Please help me understand. I have the above F8 mirror lens. I know the difference between F stop and T stop. I have measured this T stop experimentally it is higher than F8. The DOF feels very narrow ...
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1 answer
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Tips for buying modern used lenses

First, some may say this is a duplicate of What should one look for when buying a used lens?, but I see it more as an update or complement for modern lenses. I'm interested in buying a used modern ...
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3 answers
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How does crop factor apply on lenses? [duplicate]

I understand that the crop factor of a sensor multiplied by the focal length of the lens equals the focal length of an equivalent 35mm lens. Also, there are well known differences between wide, ...
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Z-mount lens on F-mount body [duplicate]

I have a Nikon D810 DSLR, which has an F-mount body. I also accidentally got an Nikkor 24-70mm Z-mount lens. I am wondering if there is a way to use the Z-mount lens on the F-mount body? I have been ...
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1 answer
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The pics taken from my canon 18-135 mm zoom lens are blurred

When ever I take photos in my canon lens during zoomed out they are of good quality and sharp but when ever I take photos that are far or somewhat near to me i find them to be blurred and lack of ...
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How do I remove this white "corrosion" from my lens ring?

I've purchased a new Sigma lens recently and everything is great about it except some white "corrosion" around the lens ring. Is it possible to safely remove it and restore the original look ...
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