What is a prime lens?

[qing02051981]

What is a prime lens and why is it useful? The lowever the aperture (f/1.2, f/1,4 etc..), the better?

Example of prime lens:
Nikon AI-S 50mm f/1.2
Nikon AF 50mm f/1.4D
Nikon AF 50mm f/1.8D

 

[plasma]

What is a prime lens and why is it useful? The lowever the aperture (f/1.2, f/1,4 etc..), the better?

Example of prime lens:
Nikon AI-S 50mm f/1.2
Nikon AF 50mm f/1.4D
Nikon AF 50mm f/1.8D

prime lense are lenses that cannot be zoomed. The bigger the aparture, the more expensive the lense

 

[miniUltraman]

Prime lens = 1 focal length (fix focal length)
Zoom lens = a range of focal length e.g. 24-70mm, 70-200mm.
"Usually" Prime lens are sharper due to a less complex design of the glass.

f/1.2 is bigger apperture than f/1.4 and f/1.4 is bigger than f/2.0. The bigger the aperture (hole), the more light can reach the sensor, the brighter you get (assuming constant shutter speed is kept) i.e. you can take pic at a lower surrounding light with bigger aperture. (I am trying to use as layman as possible. Hope it helps :sweatsm

 

[qing02051981]

prime lense are lenses that cannot be zoomed. The bigger the aparture, the more expensive the lense

When and why is it useful?
Is it because prime lens produce sharper images? I currently own a 18-200mm, wonder if I should invest in a prime lens.

 

[miniUltraman]

You have to use your "legs" to zoom in and out when you use prime lens :lovegrin:

 

[qing02051981]

You have to use your "legs" to zoom in and out when you use prime lens :lovegrin:

Have a choice between 28mm and 50mm. Which would you choose? Its a hard choice... I was considering Nikon AF 50mm f/1.8D because this is the cheapest lens I can find.

 

[zerartul]

Prime Lens due to fixed focal, have less glass thus less distortion and stuff. As such image from a prime lens is usually much better then a Zoom. Of course a consumer type of prime may lose to a professional or high grade zoom sometime, but on general a prime lens is much sharper and has a larger aperture. The downside of a prime is of course you have to fit the distance to the lens as such creates some inconvinence. Is nice to use a prime to complement your zoom. Since if you have the 18-200, depends on what you take often, for example if macro get the 105mm f2.8 prime, if portrait the 50mm 1.8, if you want wider theres the 30mm 1.4 or 20mm 1.8. In the end you can use your prime for a more definite purpose and your zoom as a general walk around lens. If you have money though theres always the high grade primes which are extremely sharp...

Do look out for third party lens like the 30 1.4 from sigma. Its quite decent and dont cost alot.

 

[qing02051981]

Prime Lens due to fixed focal, have less glass thus less distortion and stuff. As such image from a prime lens is usually much better then a Zoom. Of course a consumer type of prime may lose to a professional or high grade zoom sometime, but on general a prime lens is much sharper and has a larger aperture. The downside of a prime is of course you have to fit the distance to the lens as such creates some inconvinence. Is nice to use a prime to complement your zoom. Since if you have the 18-200, depends on what you take often, for example if macro get the 105mm f2.8 prime, if portrait the 50mm 1.8, if you want wider theres the 30mm 1.4 or 20mm 1.8. In the end you can use your prime for a more definite purpose and your zoom as a general walk around lens. If you have money though theres always the high grade primes which are extremely sharp...

Do look out for third party lens like the 30 1.4 from sigma. Its quite decent and dont cost alot.

I wish to use it to take portraits, group photos indoors etc.. I do not have a flash gun and I think getting a 50mm 1.8 will be great for indoor/lowlight photography. Am I right?

 

[miniUltraman]

I wish to use it to take portraits, group photos indoors etc.. I do not have a flash gun and I think getting a 50mm 1.8 will be great for indoor/lowlight photography. Am I right?

50mm is good for portrait but group photo indoor is too tight. moreover, you might be using a 1.5x crop nikon.. so 50mm is too long for group photo unless you can stand far behind. However, 50mm is a good portrait lens. :thumbsup:

 

[ilario]

I wish to use it to take portraits, group photos indoors etc.. I do not have a flash gun and I think getting a 50mm 1.8 will be great for indoor/lowlight photography. Am I right?

You are right. However do take note of the Crop factor. 50mm becomes an 75mm with 1.5x, so some people may not like the zoom. 35mm will be nearer to a true 50mm (52.5).

 

[night86mare]

wikipedia (and google) ish your best friend!

prime lens article from wiki

please read up on what aperture means too, typing "aperture wiki" will get you the relevant wiki article on google. cheers.

 

[GavinTing]

I wish to use it to take portraits, group photos indoors etc.. I do not have a flash gun and I think getting a 50mm 1.8 will be great for indoor/lowlight photography. Am I right?

Good for lowlight yes, but group photo no.. 50mm is abit too "zoomed" to tak a grp photos. I have trouble even at 18mm.. Unless you have a long long long hall..

The main appeal of prime lens is that its cheap and good.

 

[catchlights]

When and why is it useful?
Is it because prime lens produce sharper images? I currently own a 18-200mm, wonder if I should invest in a prime lens.

simple answer to you question,
use a masking tape to tape your lens at 50mm focal length, go out and shoot anything for a day, if you can't tahan take photos in this way, than you can forget about getting the 50mm for the time being.

 

[2.8photography]

simple answer to you question,
use a masking tape to tape your lens at 50mm focal length, go out and shoot anything for a day, if you can't tahan take photos in this way, than you can forget about getting the 50mm for the time being.

thats true, but then u dun get the f/1.8 and the sharpness of a prime, even the 50 f/1.8.

to ts: besides having better CA control, distortion and vignetting control, larger max. apertures and much better sharpness, primes are usually much smaller in size (esp lenses 135 (?) mm and below)

 

[stupidbloke]

YES primes are usually smaller sharper and relatively cheaper ( for the quality you are getting) One more thing is that, if i am not wrong, most primes out there are full frame. dont have to worry when/if you upgrade and u can use them on a film system. after i got my 50 1.4 i have not looked back since. the sharpness and color and contrast shiok! Primes force you to use ur otak to compose properly zooms i feel are a convinince that can make u lazy. (pls dun shoot me) although it can be useful at times in difficult situations.

i intend to build up an all prime set up in the future. but that of course will be when i get the $$ haha!

 

[stupidbloke]

YES primes are usually smaller sharper and relatively cheaper ( for the quality you are getting) One more thing is that, if i am not wrong, most primes out there are full frame. dont have to worry when/if you upgrade and u can use them on a film system. after i got my 50 1.4 i have not looked back since. the sharpness and color and contrast shiok! Primes force you to use ur otak to compose properly zooms i feel are a convinince that can make u lazy. (pls dun shoot me) although it can be useful at times in difficult situations.

i intend to build up an all prime set up in the future. but that of course will be when i get the $$ haha!

 

[dennisc]

And let me add, primes like f/1.2 f/1.4 can destroy your pics if improperly composed. Like blurred right eye due to extremely narrow DOF. I use Zeiss primes on a Canon system, manual focus, and IMHO, it's a winner!