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Bill70
08-05-2009, 1:41pm
After doing a lot of research, reading a lot of AP and looking at lens types I have fried the brain & confused myself to no end. :eek: Please correct the following

Canon lenses that are marked L & have a red ring indicate that they are quality lenses (This is important to me as I want to go to the canon 40D)

Lenses that have a focal length of less than 25mm are considered a wide lens. (Good for landscapes, portrait photography, groups of people etc.

The lower the f stops on the lens the bigger the aperture which lets in more light making it a faster lens.
Faster lenses allow low light photography & blurring of the background like portrait photography.
Fast lens are also good for longer focal lengths lens as it allows more light through the longer lens.

A prime lens is a lens that cannot zoom, however it is a faster lens letting on more light, has a higher optical quality & is generally cheaper than a zoom lens.

So what I have gathered so far is to choose a lens that has the lowest aperture (f/stop number) in the lens of the focal length series you require.
But how the hell do I know if the optical quality is good.
Is there a number for quality 1 to 10 or glass type?
What are the types? What good & what not?
I see many recommendations on lenses but do not understand why.
Can anyone explain & correct anything wrong that I have written so far.:(
Cheers

pgbphotographytas
08-05-2009, 1:49pm
You are correct with most of what you said above.

As far as if a lens is "good" that would be a matter of looking online for reviews and posting on here and asking what other members think, I would say except for some very expensive / specialist lenses then somebody on here would have at least some experience with most lenses on the market.

Paul

jim
08-05-2009, 1:50pm
This looks about right to me, except that prime lenses are often much more expensive than zooms (due to the wider aperture and the fact that they tend to be aimed more at pros/serious amateurs.) Though there are more serious and expensive zooms around now than there used to be.

negatron
08-05-2009, 1:56pm
This is where you post on forums liek this, because there is no rule of thumb.

look at the 70-200 f2.8 range of lenses across the brands.

They're all relatively expensive. but what makes the sigma version (lots of generations, inconsistance product quality for some) better than the tamron (slower AF speed) or say the tokina (known to have lost of soft copies floating around)?

each use lots of fancy marketing stuff (APO glass, L markings, SP markings etc)

It depends on what you want to use it for and how much you want to spend (canon 70-200 f2.8 IS for those without buget limitations)

Lenses are selected for producing good pictures->

so I look for

Sharpness
Contrast (important for me as an ex minolta user lol)
AF speed
build quality
Apature speed (Bokeh!)

As for canon L lenses, not all of them are created equal, and some have had MK2's released to improve on MK1 issues.

I guess the short answer is, there is no rule of thumb or scale. Post what you are interseted in here and look at samples pictures...

Bill70
08-05-2009, 2:13pm
Thanks guys for your comments.
I was hoping there would be an easy way to tell, but as all of you have said in one way or another, talk to those who have already used them and get opinions from the forum.
It just makes it difficult to sift through everyone’s preferences when you’re a new comer to photography, but then again everyone else has different styles & preferences.
Thanks again
:th3:

JM Tran
08-05-2009, 2:18pm
go here for lens reviews and sharpness ratings www.photozone.de

not all L lenses are optically excellent, there are 3rd party lenses which rate better than their equivalent L lens in terms of sharpness and bokeh

L stands for Luxury and u are also paying for the high construction quality, dust/weather sealing on some, and USM and IS and all that jazz:)

pgbphotographytas
08-05-2009, 2:26pm
Thanks guys for your comments.
I was hoping there would be an easy way to tell, but as all of you have said in one way or another, talk to those who have already used them and get opinions from the forum.
It just makes it difficult to sift through everyone’s preferences when you’re a new comer to photography, but then again everyone else has different styles & preferences.
Thanks again
:th3:

I can totally relate to what you are saying and yes everybody does have different views but a few things I think most people do agree on.

At the end of the day you are not going to buy a "bad camera or lens" just not what could be the best one for you.

If most people on here say the same thing then I would be fairly sure it is the right way to go.

Paul

TOM
09-05-2009, 12:14am
Bill, you are right, what you mostly pay for in a lens is speed. All modern lenses will perform well stopped down. The step from F2 to F1.4 in terms of engineering is huge. It is very well to build a lens with a large f stop, but making it sharp from corner to corner is a real challenge. This is why lenses, on a small sensor, can 'box above their weight', because the whole lens area is not being used. The Nikon 70-200 was a reveered lens until it was used with full frame cameras.

Wide angle lenses are great for landscape but so are standard and telephoto lenses. Where the wide angle lenses shine is their greater depth of field and their ability to get close to a subject. They are not intented to cram as much into the scene as possible, sometimes less is more. Traditionally, wideangles aren't used for portraiture, although I love using my 35mm lens for candid 'environment' portraiture.

Boke can make or break a lens as well Bill, and with a fast lens, particulary in standard to telphoto lenses, you will have buckets of it if you like to get close to your subjects. I am really after a super fast 35mm lens and the Voigtlander was on the short list. However, after shooting with it and viewing alot of images from this lens, i find the boke harsh and therefore I will not buy the lens.

Bill70
09-05-2009, 8:48am
Thanks for the conformation Tom.
I take it Boke or Bokeh as I have seen it spelt before is the name for the out of focus effect given by the lens correct?

ricktas
09-05-2009, 9:14am
Bokeh is a Japanese word that describes the way the out of focus (usually background) appears. Whether it looks smooth and 'creamy' or if it looks blotchy and patchy etc.

Lenses. All are manufactured in different ways and these manufacturers work within a tolerance guideline. So what gets sent to market (after they destroy the bad ones) will not all be exactly the same. You could try a friends 70-200 and then buy one, and find that yours is either a slightly better or worse version. The main issue that arises between lenses is focus. Some of the latest DSLR allow the user to 'micro-adjust' the way a lens focuses to correct these issues. Otherwise you can get your lens and camera calibrated to match each other.

For general use, most will not notice the slight (minute) focus issue differences that occur between lenses.

Analog6
09-05-2009, 9:18am
The lens considered by many to be best for portraiture (on the old 35mm film = full frame) was a 135mm. So on a crop DSLR say around 70-100.

TOM
09-05-2009, 9:25am
I have to disagree Rick. Boke IS the out of focus area, and does not describe the rendition of the such, but can be preceded with an adjective such as 'nice' or 'harsh'.

Eg. That Minolta 50mm lens renders a harsh boke.

smorter
09-05-2009, 2:09pm
No Rick is correct, it's just that unfortunately the masses have distorted the definition of the word into something else.

Bokeh is the quality of the out of focus area, not the quantity, nor the out of focus area it self. Bokeh is a noun for the quality of the rendition of out of focus areas.

A lens generally has better bokeh wide open not because the background is more blurry (though this is certainly the case), it is because the aperture diaphragm is typically a perfect circle wide open (though generally not for Macro lenses or when at closer focus distances)

If a lens had a perfect circular aperture throughout the entire focusing/zoom range, then bokeh would be identical from f/0 (theoretical) down to f/99 (limit on cameras). This is hypothetical though

Bokeh is affected by:
- Aperture Diaphragm Design
- Optical Design (i.e. Aspherical designs vs conventional)

It is not affected by DOF. How much OOF region there is is affected by DOF, but not Bokeh which describes the quality of the OOF that exists, not the amount of the OOF region, nor the OOF region itself

So it is nonsensical to have "More bokeh"

As for the word itself, "Bokeh" is a western word. The actual japanese word is "Boke" pronouced "bor care" (rhymes with "war" (bo) and "air" (ke))

"Bokeh" was coined to help pronounciation, but it's had a negative impact, with people calling it bo-kay (rhyming with day) or bo-ka (rhyming with car)...the latter which I particularly hate :)

smorter
09-05-2009, 2:19pm
Lenses. All are manufactured in different ways and these manufacturers work within a tolerance guideline. So what gets sent to market (after they destroy the bad ones) will not all be exactly the same.

This only applies to Nikon, Canon have a tendency to send the bad ones to the customers too :D

TOM
10-05-2009, 12:20pm
Boke is a Japanese word meaning haze or out of focus. How does this describe the quality of the out of focus area? The spelling was changed by an editor or reporter for a popular publication to help people pronounce it. By your definition Smorter, you would say that 'my 50mm lens has bokeh"! What does that tell me? The fact that you need to preceed the word boke with an adjective such as 'nice' or 'harsh' tells me that boke is nothing more than the out of focus area, and indicates nothing about quality.

kiwi
10-05-2009, 12:35pm
Notwithstanding the interesting debate about bokeh, a quality lens is usually bought directly adjacent to a kidney transplant operating theatre

arthurking83
10-05-2009, 6:11pm
Notwithstanding the interesting debate about bokeh, a quality lens is usually bought directly adjacent to a kidney transplant operating theatre

So I reckon by that reasoning, you've four of your 4 kidneys now Darren :p


.. and one of them(the one traded for the 400mm) must have been worth it's weight in anti-matter too!


:laughing1:

kiwi
10-05-2009, 6:31pm
Yes we are up to selling my soul

arthurking83
10-05-2009, 6:46pm
Yes we are up to selling my soul


LOL! moving to the discount brand(that starts with C) then.. huh? :D


Damned(pun intended)!! I have no soul left... so those 200/2's and 200-400/4's I've been lusting after since... whenever! .... are so far off on my current NAS horizon, it's going to take me another lifetime of soul re-manufacturing :p

But next time I'll use it more wisely, and invest before the next Aussie dollar dive!


As for the OP.. quality lenses usually cost more, or as a more obvious sign of quality... they don't devalue by all that much when it comes to resale(even on places like ebay)

There is a wide held belief that you need to stick with orginal manufacture lenses, which I don't necessarily agree with(all the time) as the third party manufacturers have long history of producing quality lenses. They may be fewer and further between, but they do exist and cost a lot less for what amounts to approximately the same thing.
Doing lots of research before you commit to a purchase, is the best way to go about spending a small fortune as it may not really save you much in actual dollar terms.. it'll really only increase the number of lenses you have to play with :th3:

Carly
06-07-2009, 3:56pm
i'm sort of confused with all the lenses naming/qualities as well.. this was a little helpful in puting them in perspective in an overview (for canon anyways) at least for different types of lenses and categories and things.. also gives you a bit of info on each one and what it does "best". I'm sure other brands have them as well.

http://www.canon.com.au/ftp/eos_ef_lens_guide%20web.pdf

Tannin
06-07-2009, 7:33pm
One thing to watch out for, Carly, is that the document you linked to is pretty old now - indeed, a real trip down memory lane, with quite a few now-discontinued models and missing quite a few of the nhewer ones. But for your purpose - getting to know the overall categories - it's just fine. After all, and ultra-wide is atill and ultra-wide, an portrait lens is still a portrait lens, and so on.

Edit: at Tannin's typing is still Tannin's typing. Or possibly worse. Sigh

Edit edit: And Tannin's typing is .... (etc.)