Focal length is the distance (measured in mm) between the surface of a lens and the focal point. Smaller focal lengths indicate wide-angle lenses, larger focal lengths indicate a telephoto lens.
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What are the technical camera specs for the HTC Wildfire S?
I am trying to do some CGI manipulations on pictures I've taken. In order to fake reality with some 3D object inserted in the picture, I need some information to configure my virtual camera so it can ...
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0answers
74 views
How to calculate the zoom power (X factor) for a lens? [duplicate]
Possible Duplicate:
How do I convert lens mm to optical zoom times?
How can I obtain the "X factor" for a lens?
I thought that to get the "X factor" I had to divide the largest focal ...
2
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1answer
130 views
EOS M focal length conversion to cropped frame and full frame camera
I am thinking about EOS M .. it looks appealing to me ... especially for Hiking .. the thing i want to know is if I use my 18-55mm Canon lens (that normally come with 550D, 600D series) on EOS M with ...
24
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3answers
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What does it really mean that telephoto lenses “flatten” scenes?
This is another perspective distortion question. I understand that perspective distortion is primarily a function of capture and viewing distance, but I am still working on fully understanding the ...
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1answer
78 views
How to calculate the new field of view from an existent one?
I have a photo having H x W (height x weight) pixels and I know, based on the EXIF, that it was shot at F1 focal length.
How many pixels I must crop (or add) in order to see how it would be the photo ...
3
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2answers
522 views
What is the conversion between focal length and times zoom? [duplicate]
Possible Duplicate:
How do I convert lens mm to optical zoom times?
What is the conversion between focal length in mm (e.g. 50mm) and x zoom (e.g. 20x) commonly used in compact cameras? Is ...
3
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1answer
362 views
Taking pictures with fixed/full focus camera
I have got a fixed focus, 5 MP camera with 3.3mm focal length (not sure what it means) on my phone. I want to know what's the best way to take pictures with since it's missing auto-focus feature. Is ...
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1answer
388 views
Should my flash zoom match my lens focal length or its 35mm equivalent?
I have a camera with an APS-C sized sensor. Should my flash zoom match my lens's actual focal length or its 35mm equivalent?
I am hoping that someone can shed some scientific light to this matter.
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4answers
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What does 'Equivalent to 1.6x the focal length of the lens' mean?
In the specifications of Canon 550D, about the lens the following is mentioned
LENS
Lens Mount EF/EF-S
Focal Length Equivalent to 1.6x the focal length of the lens
Now this is really ...
8
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2answers
2k views
Does a Nikon DX lens on a FX camera get subjected to the 1.5X crop factor?
My friend has a Nikon 35mm DX lens that I want to use on my FX camera. If I use his lens on my camera in DX mode, does the effective focal length of the lens become 35mm * 1.5 = 52.5mm, or does it ...
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2answers
2k views
Does using a lens adapter change focal length?
Does using a lens adapter change the field of view?
I recently bought a Sony NEX-5, an extra Minolta MD 50mm 1.7/f lens and a MD to E-mount adapter and I was wondering, as the adapter increases the ...
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2answers
539 views
Zoom Lens and Prime Lens Photo Comparison
Are there any examples comparing the picture quality of prime lenses and zoom lenses with the same scene and shot at the same focal length? I have not seen anything that shows me why a prime is better ...
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2answers
1k views
Why doesn't the background become blurred when I change the aperture on my Fujifilm S4000?
I am sorry if my question is too naive, but I am a complete beginner in photography, and I think I still need to understand well what aperture is. I have a Fujifilm S4000 camera, and I know I can't do ...
2
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1answer
561 views
Is it worth to buy old Sigma lens instead of Nikkor?
I'm amateur and I want to try something new. I have Nikon D3100 with Nikkor AF-S DX VR 55-200/4,0-5,6 G ED and I'm shooting everything - animals, landscape, people, sport, ... (like real amateur :D ). ...
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1answer
270 views
Does the X-Pro 1's “Lens Focal Length Setting” do anything with automatic lenses?
In the X-Pro 1's custom menu, one of the options is Focal Length Setting. The manual says:
FOCAL LENGTH SETTING (Defaults to 50mm)
Enter lens focal length when using a lens that does not ...
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3answers
797 views
How does using a lens with some focal length on a full frame camera differ from using a lens with “equivalent” focal lens on a crop camera?
As an example, a 35mm lens on a crop body (such as Nikon DX) is said to be "equivalent" to a 50mm lens on a full frame body. Equivalent here means that they will have the same field of view, but what ...
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4answers
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When would one choose a 50mm f/1.4 over 85mm f/1.8 (or vice versa) for portraits?
Say you are using a crop body, and you have both 50mm/1.4 USM and 85mm/1.8 USM lens in your bag. Now, you want to take a portrait where there is adequate light and space, and you have decided to take ...
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2answers
207 views
Can I get better image quality with a higher focal length or by cropping an image from a sharper lens?
Two well known ways to get better image quality are to use a sharper lens, and to zoom in to fill the frame (as opposed to zooming out and cropping in post). Sometimes there is a give and take between ...
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4answers
1k views
What is focal length and how does it affect my photos?
What is focal-length? Are focal-length and zoom synonymous? How does the focal length of a photo affect it?
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3answers
873 views
Does the shutter speed and focal length rule of thumb apply to cropped sensor cameras?
So, the rule of thumb for shutter speed is that it shouldn't be less than 1 / focal length. Well, that's straight forward on full frame cameras, but what about cropped sensor cameras? Is it going to ...
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1answer
524 views
What is the actual distance for taking a photograph with a 4.3-180mm Super Zoom camera lens vs. a 55-200mm DSLR lens? [closed]
What will be the true actual distance for both lens in terms of actual meters?
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4answers
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What is the reference point that the focal length of a lens is calculated from?
I understand the idea of a focal length for a single lens, i e the distance from the lens to the point at which parallel rays of light converge. However, in the case of a photographic lens with ...
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2answers
215 views
Why are the area of aperture, focal length, and amount of light specified in these terms?
So I'm looking at the wikipedia article on Aperture, and I'm a bit confused. I understand aperture to be the diameter of the hole that lets light in. In the article, someone states that
The ...
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3answers
3k views
What is the relationship of aperture, focal length, and ISO in a SLR?
I was using Nikon digital camera, and recently bought a Canon 550D. I am totally new to SLR.
I am not familiar with SLR terms: Aperture, focal length and ISO, and their relation to one another.
What ...
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2answers
1k views
Calculating focal length from photograph
I posted this question over on Stack Overflow, but someone suggested this site might be of more help to me.
I'm doing a college project where I'm trying to calculate the focal length of a camera ...
4
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4answers
490 views
Do bigger focal lengths capture more light?
I never understood what the f really stands for in the f-stop values, like f/1.8. Wikipedia explains it in various articles, but I still find it very confusing. What I understand, though, is that it ...
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3answers
1k views
What does the millimeter measurement of a macro lens mean?
I understand that the millimeter measurement on a lens is, for lack of a better term, how far it can "zoom" in or out, but what about macro lenses? What does the millimeter measurement signify? How ...
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3answers
541 views
How to compare the focal length of a 50mm prime lens with the default lens of a point and shoot camera?
To imagine the 50mm focal length of a prime lens 1.4F, can I simply zoom the lens of my point and shoot camera up to 50mm?
Will both the focal lengths be same?
Any other way to imagine the focal ...
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5answers
5k views
If I have an 85mm lens for portraits, is a 50mm useful as well?
I recently got my Canon EF 85mm f1.8, after lot of thought over if I should buy Canon EF 85mm f1.8 or Canon EF 50mm f1.4, I decided on 85mm so that I can shoot portraits of people even from a ...
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2answers
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DX 35mm vs FX 50mm
Will the picture taken from
AF-S DX NIKKOR 35mm f/1.8G and
AF-NIKKOR 50mm f/1.8G be one and the same because of the DX and FX format??
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4answers
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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 ...
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1answer
2k views
Why does my aperture setting change as I zoom the lens on my Nikon D90?
I am new to the photography field and this something which I am not able to understand. I am playing around with my Nikon D90 along with its kit lens (18-105mm).
While reading about Depth of preview, ...
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2answers
598 views
How far away can I be and still get a sharp subject with a 100mm lens?
If I have a 100mm lens, how far away can I shoot the subject? If I am shooting basketball, how far can I shoot the subject and still get a sharp picture?
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3answers
1k views
What is the meaning of single focal length?
The Nikon AF-S DX Nikkor 35mm f/1.8G is described as a single focal length lens: http://www.nikon.co.in/products.php?categoryid=1014.
What does that mean?
What are its disadvantages as compared to ...
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6answers
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How do I get the 'equivalent' focal length for a DSLR lens for my camera?
On my Nikon D3000, how do I figure the focal length equivalence? In other words, if I want a lens that is just like a 50mm lens on a 35mm film SLR, I need to multiply by a factor. What is the factor, ...
12
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4answers
323 views
What is it called when an object appears to be the same size with the eye and through the camera viewfinder?
I have a Canon 18-135 lens. I am looking into the camera viewfinder with my right eye and not through the viewfinder with my left. I start from 18mm and keep zooming in till I see a particular object ...
17
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4answers
2k views
Does my crop sensor camera actually turn my lenses into a longer focal length?
So, I mount a 200mm lens on my Canon 450D. It effectively becomes a 320mm lens. Is this the equivalent of 320mm on a full frame camera? That is, from what I've figured out I get an equivalent field of ...
3
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3answers
3k views
What mm lens for distance shots?
If I am looking to take landscape and wildlife shots and some of those shots being from a decent distance what mm lens would I need? I am not sure what else I should be adding here, I am just looking ...
6
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1answer
308 views
Does focus breathing make a lens slower when close focusing?
I've heard that focal length of some lenses will become noticeably longer when focusing to a close distance, an effect called "focus breathing". Since f-number is focal length divided by diameter of ...
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2answers
575 views
Does a crop sensor affect closest focusing distance? Why does it not affect focal length in EXIF data?
Since I am considering to buy the Nikkor 105mm micro VR, I wondered if the cropped sensor does affect the closest focusing distance of 0.31m?
Thinking about this, the following additional (and ...
4
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2answers
232 views
How rapidly does the focal length-equivalent image change by physically moving the camera?
I have recently begun moving from a Nikon APS-C DSLR to the Micro Four Thirds camera while also transitioning from using a viewfinder to using the LCD screen for framing my shots. Because of the size ...
9
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2answers
492 views
Does the size of the front glass mean anything?
Considering the Nikon lenses:
Prime lenses:
AF Nikkor 14mm f/2.8D ED has a huge front glass (●₃),
AF-S Nikkor 50mm f/1.8G has a tiny little front glass, deep inside the body (∙₁),
AF-S VR Nikkor ...
12
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4answers
3k views
How can a lens like a 18-55mm have more than one focal length?
How can a lens have a range of focal lengths? Shouldn't it be a single number?
Isn't focal length supposed to be fixed for a lens of a particular shape and geometry?
What am I missing?
How many ...
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3answers
339 views
Should I upgrade my camera or lens to shoot pro hockey games?
I've gotten the opportunity to shoot pro hockey games. My current gear doesn't cut it:
Nikon D70
Nikon 18-70mm F/3.5-4.5 Kit lens
Nikon 70-300mm F/4-5.6 D
Nikon 50mm 1.8D
Monopod
From where i'm ...
4
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2answers
639 views
Is it normal for focal length to change while focusing?
When I change the focus distance on my Pentax 55-300mm lens, the focal length appears to change. More specifically, the lens appears to zoom in as I focus towards the minimum focusing distance. This ...
10
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3answers
2k views
How does changing focal length affect depth of field?
I'm curious about how my "area of acceptable focus" changes when the focal length of the lens I'm using changes as I zoom (or switch lenses). In particular, I'd like to know how the front & back ...
9
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2answers
1k views
Why is depth of field affected by focal length?
As the focal length decreases, the depth of field increases as well. Why is this? I'm not so much interested in a physics lesson as I am interested in a simple, down-to-earth explanation.
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1answer
515 views
Does focal length affect diffraction, in addition to aperture?
The reason I ask is that f/18 on a 24mm lens = 1.5mm, and f/18 on a 180mm lens = 10mm. I thought diffraction is due to the small physical size of the aperture, rather than the f-ratio, yet I only ever ...
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3answers
3k views
What software can show my most frequently used focal length?
Many people recommend a focal length of 35mm, 50mm, and sometimes even 85mm and upwards for those interested in purchasing a prime lens. I, however, would like to figure out what focal length(s) I use ...
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1answer
698 views
Which famous photographers used mostly one lens throughout their careers? [closed]
Which famous or outstanding photographers did use mostly only one focal length throughout their career and what focal length did they use? For medium and large format photography, please indicate a ...
