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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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83
votes
6answers
38k views

What is “angle of view” in photography?

I read on the Lens Buying Guide @ neocamera: Focal-length determines the angle-of-view seen through a lens for a given sensor-size. With a full-frame sensor a lens gives the same angle-of-view ...
191
votes
15answers
125k views

What do all those cryptic number and letter codes in a lens name mean?

When looking at a lens name, there are a lot acronyms describing its features (often specific to the manufacturer). Examples, Nikon: Nikon AF-S DX 16-85mm VR f/3.5-5.6G IF-ED Nikon AF-I 600mm f/4D ...
47
votes
9answers
29k views

Which focal-length lens is usually used for portrait photography, and why?

What focal length or range of focal lengths are usually used for portraits? What is used by professionals? Why would one select a certain focal length? What are the advantages and disadvantages of ...
82
votes
11answers
7k views

How much do lens lineups vary across DSLR platforms?

I was reading this question and recalled how often I hear the advice "choose your lenses and then choose the body that matches" in the context of deciding on a camera platform (Nikon/Canon/Pentax/Sony,...
11
votes
6answers
10k views

Why do Full Frame lenses and crop body lenses exhibit the same crop factor when used on a crop body camera?

I have a Canon 7D, which has a crop factor of 1.6x. When using a Canon EF-S lens I get the focal length stated on the lens, when using a Canon EF lens I get the focal length times 1.6 when used on ...
64
votes
7answers
389k views

How do I convert lens focal length (mm) to x-times optical zoom?

What is the rule to convert the 'mm' notation to the 'optical zoom' notation? I searched a bit and found this one: optical zoom = maximum focal length / minimum focal length For example a 18-55mm ...
29
votes
6answers
11k views

Is there a difference between taking a far shot on a 50mm lens and a close shot on a 35mm lens?

I am looking for a prime lens to pick up, and I'm wondering if there is any difference between 35mm and 50mm in terms of the end product if I just stand back more with the 50mm. I use the Sony a6000 ...
49
votes
3answers
7k views

What image-quality characteristics make a lens good or bad?

When reading lens reviews on the Internet, I often find subjective statements about the image quality that a lens produces, such as "good contrast" or "sharp". The problem is that I don't think I am ...
25
votes
6answers
100k views

How do I find the right size of filters for a lens?

I was looking to get a circular polarizing filter and an UV filter for my Canon 550D, 18-135mm lens. When I checked online I found these filters came in different sizes, like 62mm, 67mm, 72mm, 77mm. ...
18
votes
7answers
2k views

Lens upgrade paths (sub $1000) for the EF-S 18-55mm IS kit lens for Canon APS-C cameras [closed]

This is somewhat a follow-up to my earlier question on the limitations of the kit lens. I have browsed through quite a lot of sites including this one for user opinions & reviews of different ...
17
votes
4answers
4k views

What is the difference between perspective distortion and barrel or pincushion distortion?

I've heard of: perspective distortion barrel distortion pincushion distortion mustache distortion What are these different types of distortion, and how do they relate? What causes them, and can they ...
16
votes
4answers
35k views

Why prefer the 18-55mm and 55-250mm lenses vs 18-200mm?

There seems to be a preference for to have the 18 mm - 55 mm 55 mm - 250 mm lenses, but no mention of why they're better than a single 18-200mm. Could someone please explain why the two separate ...
33
votes
4answers
21k views

What is a macro lens?

I've read a few threads on here that mention some elementary descriptions of macro lenses and found some marketing fluff in the box for my Canon about them as well, but being a complete novice I was ...
8
votes
4answers
2k views

Why did manufacturers stop including DOF scales on lenses?

Seriously why? I hate it and I hate memorizing it or check my phone app for the depth of field of the current aperture. I find it so useful in old lenses. The DOF preview doesn't help that much ...
69
votes
11answers
12k views

Are there any downsides to using a good-quality UV filter?

Are there any real downsides to using a UV filter? I know that a poor quality UV filter can effect image quality ... but, assuming I use a good quality UV filter, will that actually be an issue? Is ...
33
votes
13answers
26k views

Should I buy a camera with kit lens, or body plus lens separately?

I am planning to buy a DSLR soon. Before I zero in on the model, I want to know whether it is advisable to buy a kit (body + 18-55 lens) or not? OR should I go for the camera-body and the lens ...
3
votes
1answer
938 views

Pictures of surfers start in focus then go out of focus?

I was recently shooting some surfers after a session with my 7D and Tamron 18-270mm F/3.5-6.3 Di II VC PZD. I started shooting while he was in focus, then as he got to the main part of the maneuver ...
69
votes
17answers
9k views

Where can I find reviews of lenses?

I want to check reviews when deciding to buy a lens. There are so many factors beyond what is written in the name. Where can I find such reviews? What information does each site cover? Which reviews ...
4
votes
2answers
3k views

Does wide angle equivalent in crop sensor skew image?

I see many posts on both this forum and elsewhere the discuss the use of a wide angle on a crop sensor. For example, they discuss how at 14mm lens is 14mm on a 35mm film or full frame, but with a 1....
38
votes
8answers
10k views

Why do people recommend 50mm or other prime lenses as starting lenses for learning photography?

I've seen quite a few people recommend the 50mm prime lenses, in particular the sub-$100 50mm/f1.8, as a starting lens for photographers (especially because they're likely to be using cameras with ...
30
votes
2answers
24k views

What is T-number / T-stop?

Usually, when discussing aperture of a lens, F-stop and F-number are used for quantifying. But some photographers, and especially videographers, also mention T-stop. The concept and numbering used (e....
11
votes
4answers
16k views

How do zoom, magnification, and focal length relate?

Zoom lenses and cameras with superzooms are often sold with a times ("×") zoom number — like a 12x zoom or 30x zoom. The question How do I convert lens focal length (mm) to x-times optical zoom? ...
18
votes
8answers
4k views

Is a UV Filter required/recommended for lens protection?

Is it still required/highly recommended that I buy a UV or similar filter to 'protect' the front element of my lens? I ask because this advice has been around for 30 years and you would think that ...
15
votes
7answers
7k views

What is a normal lens?

I've heard people call 50mm lenses "normal lenses". For a lens to be considered normal, does it have to be exactly 50mm or is there some leeway? Does the normal focal length depend on crop factor of ...
76
votes
16answers
26k views

Is it lenses which make your photographs, not camera bodies?

I read somewhere on this site itself that you should spend more on your lenses and less on your camera bodies. Is it a myth or a fact that mostly it is the lenses which make your photographs not the ...
13
votes
7answers
4k views

How to know you've outgrown your equipment?

I have only started shooting recently, as a hobby. I use Canon EOS M100. I use a EF to EF-M adapter to use EF 50mm f/1.2L USM. The camera seems to have trouble focusing and light metering (with auto ...
68
votes
6answers
13k views

Why are wide-angle lenses so much more expensive?

What is it about wide-angle lenses that makes them so much more expensive than an equivalent-quality tele or prime lens? Take the Canon EF-S 10-22mm USM, for example. RRP is nearly £1,000! Are they ...
34
votes
4answers
7k views

How do you find out the “sweet spot” of a lens?

I've tried googling this, but have never found a satisfactory answer. I've heard the term "sweet spot" thrown around by some photographers to mean the f-stop of a lens which results in the highest ...
45
votes
6answers
10k views

How do constant aperture zoom lenses work?

Cheaper zoom lenses usually are faster at the wide end and slower at the long end (for example, the $150 Canon EF-S 18-55mm f/3.5-5.6). More expensive constant-aperture zoom lenses have the same ...
8
votes
1answer
1k views

What lens characteristics are important in star photography?

In optimal world I would buy a lens that is good in every way. But I'm on a budget and have to find a balance in quality and price. I'm looking for a lens for star photography, so in my case it will ...
30
votes
14answers
22k views

Which lenses should be included in a travel photography kit?

On a crop sensor camera, e.g. Canon EOS 7D, what would be the best kit to travel with around Europe for a few weeks? My shooting style will focus on landscape, architecture, and general travel shots (...
20
votes
3answers
2k views

What is Chromatic Aberration?

What is Chromatic Aberration? Is it a physical part of the lens, or just an optical illusion?
35
votes
3answers
10k views

How can I test a new lens to make sure it is operating correctly?

How can I test a new lens to make sure it is operating correctly? I found two similar questions with answers specific to things such as sharpness and focus, but I want to cover any and all possible ...
29
votes
9answers
2k views

How to choose a lens for my first DSLR?

I am considering buying my first DSLR. How do I know whether I need a 18-200 lens, 17-85, or 18-55? Or something else?
22
votes
4answers
17k views

How do camera body motors compare to in-lens motors for focusing?

What is the difference between using a motor on the camera body and the motor built into lenses? Aside from how both compare in terms of speed, what differences would I notice if I use a body with a ...
18
votes
5answers
14k views

What focal length gives a “normal” field-of-view on APS-C cameras?

I wish to purchase a "standard angle-of-view" prime lens for my Canon Rebel, which has an APS-C sized sensor. Various articles note that the popular "nifty 50mm" lenses are a little too much of a ...
20
votes
2answers
5k views

Why do zoom lenses and compact cameras have varied maximum aperture across the zoom range?

Why does a camera's maximum (allowed) aperture get smaller when you increase its zoom?
12
votes
5answers
19k views

What's the difference between using a 50mm f/1.8G and a 50mm f/1.8D with a Nikon D80?

Recently, Nikon announced their new 50mm f/1.8G lens, as revamp of the old 50mm f/1.8D. Here's how Gizmodo describes the difference: The main difference between this new "nifty fifty" and the ...
25
votes
4answers
5k views

What is a “fast” lens?

I've been reading lots of camera reviews lately and have ran across several references to "fast" lenses. What exactly is a fast lens and what are its advantages compared to other lenses?
19
votes
6answers
4k views

What are the limitations of a typical kit lens as a general purpose lens?

I have a Canon EOS 550d with the 18-55mm IS kit lens. I have done quite a bit of shooting with it over the last few months (portraits, nature, night shots etc), and find the image quality to be pretty ...
9
votes
2answers
2k views

Dust-like speck visible every few pictures — is it dust, or worse?

I seem to have to dust-like speck on my Sony Cybershot S950's lens, but it appears randomly every few pictures. Could something be going bad internally?
65
votes
9answers
7k views

Why do some lenses cost 10 times as much when the specs are very close?

For example, a Canon 50mm f/1.8 lens is about US$110, while another Canon 50mm f/1.2 lens is about 14 times as expensive, at about $1450. Is the 1.8 or 1.2 the main reason for the price difference? ...
20
votes
6answers
64k views

If I have a 18-55mm lens, is there a point in buying a 35mm prime lens?

I have the Nikon kit lens that came with a D5100 — the kit lens is 18-55mm f/3.5-5.6 AF-S DX VR Nikkor Zoom. I was thinking of getting a fast lens and I am looking to buy the Nikon 35mm f/1.8G DX. ...
18
votes
1answer
6k views

Why do some lenses focus past infinity? [duplicate]

On the kit 18-55 lens that came with my Nikon D5100 I have noticed that when trying to focus on infinity for shots in dark conditions (star-trails, etc) the lens tends to move past infinity out of ...
12
votes
3answers
2k views

What type of lens will auto-focus on Nikon bodies without a focus motor?

I know my D40 doesn't have a motor in it to auto-focus lenses. What type of lens has the motor in it? How can I know which lenses will and will not work?
22
votes
7answers
11k views

How can aperture be f/11 on a lens with an aperture range designation of 3.5-5.6?

I made a series of outdoor shots with Nikon D5000, with the 18-55mm 1:3.5-5.6G VR kit lens. On some shots, I see in the EXIF info f/11, and in another shot, f/9. How can that be, that the f-number ...
18
votes
5answers
2k views

What is an ultra-wide lens?

What is the point at which a lens is considered "ultra-wide angle" vs just wide angle?
13
votes
2answers
31k views

What is CLA service?

I've seen the term used in used lens listings, e.g "recently CLA'd". I have a few questions, but I think they're related enough to only warrant one post: What does CLA stand for, and what is it? How ...
12
votes
9answers
17k views

Nikkor f/1.8G 35mm or 50mm?

I'm new to photography. I got a Nikon D3100 with the 18-55 kit lens. I was looking to buy a f/1.8 prime lens, and I found two options: AF-S DX NIKKOR 35mm f/1.8G AF-S DX NIKKOR 50mm f/1.8G How ...
50
votes
8answers
13k views

Why is the 50mm prime lens the most standard?

Seems that most photographers choose the 50mm as their prime lens (at least from what I've read). I'm looking at getting a prime lens for my Nikon D3000 and the cost difference between the 35mm 1.8 ...