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.

Filter by
Sorted by
Tagged with
0 votes
2 answers
34 views

How is reflection sharp when not in DOF range? [duplicate]

This is baffling to me. When you use fast lens and you focus on a subject, you'd think that everything that's not in DOF range would be blurred but this is not the case if the object is a mirror or ...
  • 201
0 votes
0 answers
39 views

Nikon D3100 Making weird sounds while trying to take photo

Whenever it try to take a photo on my nikon D3100 it keeps making weird motor sounds. I have dropped its lens once about 3 months ago but has been working fine until now. Here's a link to the sounds ...
0 votes
1 answer
62 views

How can I disassemble a Computar M8513 lens?

How can I disassemble a Computar M8513 lens? It is a C-mount lens with a focal length of 8.5 and f1:1.3, it has manual focus and manual aperture. The aperture/iris can be opened/closed rotating the ...
0 votes
2 answers
105 views

What lens do I need?

I am looking to mimic the below photos to the best of my ability. Hue, the softness of the photo, cool toned, range of view, etc. I have a Sony a7III. I understand editing is done to the photo after ...
  • 3
0 votes
1 answer
68 views

Why can't my Canon 18-135mm IS focus to infinity when zoomed past 100mm?

My EF-S 18-135mm f/3.5-5.6 IS [non-STM/non-USM] cannot focus on my 7D to infinity when it is zoomed past 100mm in both auto and manual focus. It can only focus on objects at a shorter distance (say &...
  • 1
0 votes
1 answer
84 views

Do all macro lenses have dark shadows when shooting?

Is it normal for a macro lens purchased to have dark shadows during photography? If so, how can I use this shadow to perfect my photography?
  • 1
1 vote
0 answers
33 views

How do I figure out which C adapter I need to use a CX4 Microscope Camera?

I work on very small electronics and I was trying to get a camera to take pictures of the boards that I work on. I ordered a CX4 cmos camera and got a C adapter to attach it to my microscope. It ...
  • 11
0 votes
1 answer
108 views

What focal length is best for photography of rugs?

What focal length is best for photography of rugs? I am choosing between a Sony 16-50mm lens and a 50-210mm lens. Rugs size small and medium sized 2x3m Notes :i have 2 only lenses size 16:50 mm and 50:...
0 votes
2 answers
57 views

Can I mount a EF-M lens onto a C/CS-mount camera?

I have a Raspberry Pi High Quality Camera (C/CS-mount), and would like to mount the Canon EF-M 28mm f/3.5 Macro IS STM to it (EF-M). I have been looking for adapters, but can't find any. This got me ...
  • 3
0 votes
1 answer
47 views

How can I place an IR cut filter on an M12 lens?

I have an M12 lens and my camera doesn't have an IR cut filter. It's difficult to find an IR cut lens for my specific sensor size and desired focal length (sensor size 1/2.3, focal 2-4mm). Is there a ...
1 vote
5 answers
434 views

Are faster lenses inherently better than alternatives if shooting with same aperture?

Let's suppose there is a faster prime and slower zoom lens which covers the same focal length and I want to shoot landscape scenes with certain fixed aperture to make sure the depth of field is big ...
0 votes
1 answer
45 views

If I collimate light with a couple lens, how do I find the magnification?

Say I have an object at 40 cm from a convex 20 cm focal length lens, then a concave -30 cm focal length lens 10 cm behind that. This would give an image at infinity, which one could take a picture of, ...
1 vote
4 answers
122 views

What is the definition of focal length for a camera lens?

I came across many articles where the focal length of a camera lens is defined as the distance between the optical centre of the lens and the sensor. One such article is here: https://photographylife....
0 votes
2 answers
111 views

I want to measure far distance focus in a short space, but give myself a greater FOV, how would I do that?

Building off of this question, say I put a 1 m lens in front of a camera so I can see a virtual image at 500 m to focus to, when I place an object within the focal length (0.998 m), but I want a ...
0 votes
2 answers
125 views

I want to focus at far distances but close, what lens could I use?

I want to be able to set the focus at far distances, like 500 m, but in a smaller setting, like 5 m. What lens could I use to achieve this? I have found this lens that achieves it for a FOV of 120 ...
5 votes
2 answers
263 views

What does an 85mm prime offer that a 50mm does not?

Putting taste/preference/opinion aside, I wonder whether I'm missing something, either on the technical side or the artistic side. My question only addresses the context of digital cameras with "...
  • 207
0 votes
4 answers
165 views

Which is the cause of Barrel and Pincushion distortion?

Barrel and Pincushion distortion are due to the fact that the magnification of the lens changes as you get further off axis. Let's consider a single thin lens with an aperture stop. These two pictures ...
  • 484
0 votes
0 answers
25 views

Are there software tools to help analyze EXIF metadata to help guide new lens choices? [duplicate]

I have a zoom lens (18-135mm on an APS-C body) and I am starting to look at options to upgrade to a different lens. I bought my camera and lens together and while I used a different lens (70-350mm) ...
  • 113
0 votes
3 answers
143 views

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 ...
  • 484
2 votes
3 answers
174 views

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 ...
0 votes
1 answer
93 views

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
89 views

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. ...
  • 31
3 votes
1 answer
121 views

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 ...
  • 484
3 votes
2 answers
97 views

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?
  • 1,290
1 vote
1 answer
83 views

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
114 views

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 ...
0 votes
0 answers
72 views

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 -...
  • 101
4 votes
2 answers
1k views

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 ...
0 votes
3 answers
136 views

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 ...
  • 484
1 vote
1 answer
46 views

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'...
1 vote
3 answers
85 views

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 ...
1 vote
1 answer
72 views

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 ...
  • 55
0 votes
3 answers
108 views

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 ...
  • 484
0 votes
1 answer
53 views

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?
2 votes
1 answer
80 views

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 ...
  • 153
0 votes
3 answers
135 views

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
144 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 ...
  • 399
1 vote
3 answers
195 views

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 ...
0 votes
0 answers
49 views

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?
  • 11
0 votes
4 answers
170 views

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 ...
0 votes
0 answers
53 views

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
158 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
135 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. ...
0 votes
1 answer
121 views

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
135 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, ...
  • 1,577
0 votes
0 answers
28 views

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 ...
0 votes
1 answer
63 views

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 ...
  • 1
1 vote
1 answer
86 views

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. ...
  • 11
0 votes
1 answer
40 views

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?

1
2 3 4 5
61