Lense quality differences

[sincere]

How do i determine what lense gives a good image quality and sharpness? I know it also depends on the actual photo being shot but i am sure that besides that, there are other factors that play a major role.

 

[Mike_E]

Qualify "good". Do you mean for a 40" print or a 4x6. Or are you wanting a desktop photo or doing espionage?

I don't mean to be a smart-a** but Different tools are used for different jobs and without knowing which job is intended no recommendation can be fully accurate. (while we are at our keyboards we are all full of our experience and say a lot of things but it's what comes out on the media that really matters.) To me good is good enough that you can't tell so that on a 4x6 a little lens will do just fine. On a 40" I need to drag out the beasts.

As far as contrast and color rendition, research and testing are your best friends. (that's and, not or )

mike

 

[sincere]

OK smart-one, i intend to use it for portraits and such so image quality and sharpness plays a very important role.

 

[JIP]

You can determine the quality of a lens by the maximum aperture. for example this lens http://www.bhphotovideo.com/c/product/274780-USA/Nikon_2139_70_200mm_f_2_8D_VR_G_AFS.html 70-200VR 2.8 is going to be better than this lens http://www.bhphotovideo.com/c/product/486717-USA/Nikon_2166_55_200mm_f_4_5_6G_ED_AF_S.html 55-200 f 4-56. The first lens has a faster maximum aperture and to acheive this there are more and larger elements and the glass is mad to a more exacting standard. In general you can figure out the quality of a lens by this also, the lenses that are VR or in Canon's case IS are generally better lenses. Another way to tell with Nikon is if a lens has ED glass and I think Canon has the L series of lenses.

 

[Mike_E]

Again, resolution determines acceptable print size. Look at a photo on whatever viewing software you have. As you increase magnification the photo gets fuzzier. It is the same with prints so if you intend to sell 16X20s or larger get the L glass, but if an 8X10 is the largest you are likely to print L glass would be over kill.

If you just want the most expensive glass then get it. But just like cars, the care and feeding of exotic automobiles (camera equipment) is expensive.

mike

 

[Zatodragon]

The aperture can play a important part of quality, but not always. But if the aperture is a nice 2.8 or faster, the lens will be good.

But you will want to be doing lots of reviewing and reading up on lenses. It's the best way to find out. For portrait work, a lot of people like using prime lenses. 50mm f/1.8, 85mm f/1.8, and many other fixed focal length lenses generally are tack sharp and beautiful quality for portrait work.

 

[Mike_E]

One last thing and I'll leave you all alone with this. For portraits of people you really don't want Tack sharp. The imperfections in the skin (and pores even) that are rendered are not flattering to your subjects (read that mortals) unless you are photographing supermodels who have none. That's why there is so much attention paid to the blurring effects in post production software and various filters for film cameras. And the background is supposed to be blurred anyway which is why the term Bokeh gets bandied around so much.
If you want a lens strictly for portraiture then next best is probably good enough and if you really want the most expensive then just buy an action to go with it.

mike

 

[Stretch Armstrong]

My approach on lenses is this. I try to buy the best I can which usually means the L series. I currently have the 30D but will be upgrading to either the 5d or Mark III in the next 12 to 14 months. I mention this because I don't want to have to re-buy lenses when I step up to a full frame sensor.

For portraits, I use the Canon 85mm f1.2L. All in all, it does a pretty good job.


Good luck to you.

 

[panocho]

You can determine the quality of a lens by the maximum aperture.

image quality rendered by a lens and the maximun aperture of a lens are two separate things. It is true, however, that lenses with great maximun apertures tend to give better image quality, just because they are usually conceived for professional, who not only need very fast lenses but also good image quality and sharpness. But although they may usually coincide they still are two separate things.

In fact, some ultra-fast lenses (50mm f1.2) are less sharp and give poorer image quality than slower ones (50mm f1.4 or f1.8).

On the other hand, I'm with Mike: top sharpness should not be a requirement for portraiture.

In general terms, I would say that you know when a lens gives a better image quality and sharpness when you use it and compare the result with some other lens's, as simple as that

 

[deanimator]

image quality rendered by a lens and the maximun aperture of a lens are two separate things. It is true, however, that lenses with great maximun apertures tend to give better image quality...

At their max apertures this is not generally true...lens performance here is designed for speed, and sharpness is much less important. Many other lens faults also appear such as vignetting, color fringing, barrel distortion. I even see this on my L series lenses

In fact, some ultra-fast lenses (50mm f1.2) are less sharp and give poorer image quality than slower ones (50mm f1.4 or f1.8).

Yup...methinks this is what I´m saying above. This is no surprise...it´s simply harder to make these lenses.
However, at any aperture, a "pro" lens is always gonna be sharper than an "amateur" lens...therefore the price tells you a lot!

On the other hand, I'm with Mike: top sharpness should not be a requirement for portraiture.

Yup...me too.

 

[deanimator]

Ask yourself this: Do you know at what aperture your lens performs the best?

The answer may surprise you!

 

[Jestev]

Ask yourself this: Do you know at what aperture your lens performs the best?

The answer may surprise you!

Performance is based on what you want. If you want a tiny strip of focus the largest aperture (f/1.8 or whatever) would be the best "performer," but if you wanted it to be the sharpest with the most in focus it would be two stops from minimum aperture (like f/11).

 

[JIP]

How do i determine what lense gives a good image quality and sharpness? I know it also depends on the actual photo being shot but i am sure that besides that, there are other factors that play a major role.

There have been alot of answers given here but the bottom line to this question is the "quality/sharpness" of a lens can be determined by the maximum aperture. This is not saying what aperture you will be shooting your pictures at it is just stating what will determine the overall quality of your lens. Also as has been said by someone price is a determiner.

 

[RedDevilUK]

Ask yourself this: Do you know at what aperture your lens performs the best?

The answer may surprise you!

this is me all over!!

all this talk of 1.8

i nearly never use 3.5!!! so the chance of me paying extra £1000's for the 1.x version of my lenses is remote

up on the Hills in bright sunshine an F1.8 would be a waste of time.

 

[JIP]

this is me all over!!

all this talk of 1.8

i nearly never use 3.5!!! so the chance of me paying extra £1000's for the 1.x version of my lenses is remote

up on the Hills in bright sunshine an F1.8 would be a waste of time.

I repeat wether or not you use f/1.8 a lens with a 1.8 max aperture is better and sharper than one with a max of 3.5. It does not matter what aperture you like to use.