lenses.

KryptoNeo

KryptoNeo

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Stephen
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Please forgive me for asking such n00bquestion and its probably a stupid question too, but i still have a lot to learn.

could someone please tell me why a 70-200mm lens is better and more expensive than a 70-300mm lens and also how a 50mm lens would also cost more than a 70-300mm lens aswell.

i dont really understand the numbers on them but i just assumed that 300mm was better than 200mm. im obviously wrong. im also unsure of the meaning of the other little number E.g on my 70-300mm sony lens i have 4.5-5.6/70-300
what do the numbers with decimals mean

any help in understanding these would be much appreciated

cheers
Steve
 
The mm numbers are the focal lengths of the image. The large the number, the smaller the angle of view, hence greater the zoom.

The cost of the lenses are to do with optics and features. I don't want to open a can of worms with that.
 
If your comapring the 70-200 F4 L to the 70-300 IS F4-5.6 the 70-200 is an L series (professional range) lens, buils quality can be better as can be optics used etc and it's a constant F4 appature throughout the focal length range. The 70-300 IS lens is a good quality and has IS in built (probably best described as high quality consumer lens).

As re the 50mm primes, same thing applies

IMO I would say
50mm F1.8 (reasonable quality consummer lens)
50mm F1.4 (high quality consummer lens)
50mm F1.2 (top quality with a price to match lens)


Hope this helps :thumbs:
 
The numbers with decimals are the aperture available at both ends of the lens... at 70 you will be able to open it up to f4.5 but at 300 this will be f5.6

Someone might be able to correct me if that isn't 100% accurate.

A lens can be more or less expensive than another one for a number of reasons. Build quality, brand, the glass that is used, and how "Fast" it is referring to how large an aperture it has. For example a lens that can do F2.8 at 300mm will be alot more expensive than one that can only do f5.6

It's confusing, but the way I see it is don't try and worry about it till you know what you want.. I wanted a lens for low light conditions so therefore the F number was most important, then I looked at the focal length (mm) and decided that a good lens would be the 50mm 1.8 from canon.
 
You pay extra for several things with lenses:
- Constant aperture
- Fast (large) aperture
- Good optics (and excellent image quality as a result)
- Build quality

Constant aperture = more cash
Fast aperture = lots more cash
etc...

In one of tyour examples, if you compare the Canon 70-200 F/2.8 to the Canon 75-300 F/3.5-F/5.6 the first lens has a faster constant aperture, top class optics and IQ and Canons durable and weather sealed case. The 75-300 is like a pringles tin stuffed with a couple of milk bottle bottoms in comparison, hence the substantial difference in price ;)

There are other things that alter the price as well, like how new they are, focussing speed and probably a hundred others.

EDIT: Must type faster!
 
As stated,
Comes down to quality of glass and to the biggest extent the aperture ability the f number as yours is say 4.5-5.6 this is the maximum aperture your lens will shoot at this is the amount of light it lets in.
The confusing thing is the smaller the number such as 1.8 means it lets more light in and can shoot far better than a 4.5 in lower light conditions.
Your 70-300 4.5-5.6 would be wide open at 70mm 4.5 and at the other end it would be 5.6 at the 300mm end.

Another point is is all relative to the length of zoom so a 300mm F4 is Not as good as the 500mm F4.

The thing also about the low F number can mean you can use a tele converter
to get more magnification this ups the say 300mm to 450mm but also alters the F number so lets less light in.

I think ive got that right but stand to be corrected, thats my get out clause.

Jeez i know im a slow typer and spelling terrible but there was only one reply when i started:bang:
 
Awesome guys, thanks alot for your your replies. i think i understand it now.
I am glad i can ask what to you guys might seem like a stupid question without being ridiculed. I asked this question on another forum and just got abused for being so stupid.
So thanks again guys

steve
 
KryptoNeo said:
Awesome guys, thanks alot for your your replies. i think i understand it now.
I am glad i can ask what to you guys might seem like a stupid question without being ridiculed. I asked this question on another forum and just got abused for being so stupid.
So thanks again guys

steve
Click to expand...

Your welcome

Now let the insults begin :lol::lol:
 
KryptoNeo said:
Awesome guys, thanks alot for your your replies. i think i understand it now.
I am glad i can ask what to you guys might seem like a stupid question without being ridiculed. I asked this question on another forum and just got abused for being so stupid.
So thanks again guys

steve
Click to expand...

That's because like every aspect of live you will find communities of people who think they are better than everyone else because they know something about what they do. It never occurs to them that they once didn't know either.... luckily this forum is an exception and is generally very useful, I very rarely stick around in a forum as I get bored of all the idiots but have to say this one is great
 
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