50mm lens CA/fringing

[wider]

is the nikkor 50mm f1.4 any better than the f1.8 version in terms of chromatic abberation/fringing? or do we need to wait for a 'lens update' before these issues will go away?

the image attached is a test shot, still the fringing is quite irritating.

[stephenvandermark]

not sure, but according to the review sites the 50/1.4 seems to be better. Check out the http://www.photozone.de site where there are some interesting reviews, including both lenses you mention,

Cheers,

Stephen

[christiand]

Hi all,

now this is interesting (I think it is ...)
This is just a thought - pretty unsubstantiated (due to lack of research and experience) - however someone might know:

CA/fringing - is it actually related or caused by the lens or perhaps by the sensor on the camera ?
Who would like to answer this question ?

Regards,
Christian

[wider]

i have been recently thinking the same thing christiand

would like to do some test shots with the 50mm 1.8 and the 18-70mm

might post some results up later

[surenj]

CA I think is lens related..

[DaveB]

Is that photo meant to illustrate a problem with CA? It's not very obvious: where are you seeing a problem?

There is certainly flare in that image, but that's not chromatic aberration.

[wider]

as the topic states, the ca/fringing around the over-exposed spokes and upper rim of the wheel

i know its on an overexposed example and not exactly real-world, but if i take shots at night where lights will get blown out, then this is an issue as the image comes out poorly

yes i know there is also flare, but am not concerned with that atm

[DaveB]

as the topic states, the ca/fringing around the over-exposed spokes and upper rim of the wheel

That is not CA (Chromatic Aberration). Partly there's flare across this image, but mostly the "blooming" around the overexposed alloy is the way the camera's sensor is dealing with the overexposure.

The usual form of chromatic aberration we see is where the lens fails to focus all the colours at the same point (especially at wide angles) and this effect increases the further you get from the centre of the image circle. So the colours get smeared towards the edges of the frame (usually resulting in red and/or green fringes to lines tangential to the centre). If there's any CA in this image it's hard to make out at this size (it would be more obvious at 100%, but only towards the edges of the frame).

[DaveB]

For illustration, I've artificially added some red/cyan CA to your image:



That sort of problem isn't apparent in your version, so I don't think you meant chromatic aberration when you complained of "CA". Am I off track?

[johnd]

I understand what Dave is saying about CA. When I first saw this image I thought that it didn't look like any CA I have experienced. However, I think the question was about using a different lens to get a better result. I wouldn't have a clue whether the 50 1.4 would behave better. Maybe the newer N crystal Nikkors may behave better, I don't know. You might just have to borrow one and experiment.

On another tack, I have found that Capture NX is very very good at removing CA from raw images. (OK it is not CA but...) It would be interesting to run this image thru Capture NX if indeed you have a raw file.

Cheers
John

[wider]

yeah im with you dave, as i too am not sure of the exact terminology...

i noticed an example here, on a review of a tokina 11-16mm lens i was looking at



taken from http://www.photozone.de/Reviews/Canon%2 ... on?start=1

the first shot i posted is doing a similar thing - blue/purple fringing on the dark areas of the image brought on by the bright aspects beside them. but im not seeing the cyan or red CA either - like you mentioned dave. ironically to my untrained eye i usually only notice the purple part of CA...

might try it with a newer lens to see what i get

[wider]

well in reply to my own topic, seems the purple fringing that i was experiencing is mostly due to the apetures i have been using.

f1.8 has horrible fringing around blown out objects, when closed to f2 the fringing is reduced by half. 2.2 and 2.4 are better again. wonder if the new nano lenses can improve on this?

[chrisk]

i used to have the 1.8 and noticed some fringing around tops of trees that were backlit. i rarely shoot the 1.4 any smaller than f4 and i have not so far noticed it the same problem at all. mind you i have not ben "looking" for it.

personally, i would not be buying a 1.4 until the new af-s version is released. if there is no new 50/afs then i would seriously consider the new HSM sigma 50/1.4 which outperforms the nikkor at wide apertures by a decent margin.

[monyx]

The 1.4 is afflicted by purple fringing wide-open, needs to be stopped down:

[gstark]

The 1.4 is afflicted by purple fringing wide-open, needs to be stopped down:

That is what is called an expected outcome. It's not really an issue with the lens; you need to look at what the subject matter is, and the contrast range that you're trying to capture here.

I'm not suggesting that it's good, but I am saying that it is not a problem with one's kit. You are shooting beyond the camera's design scope. See what happens when you drive your car into a brick wall at 140Kph: there's very little difference in that the outcomes will be a bloody mess.

As a matter of housekeeping, could you please take a moment to add your location - a MEANINGFUL location - to your profile, please? This is a requirement of membership, and it is stated, along with the meaning of "meaningful", in way too many parts of the forum, and in way too many posts, for you to not be aware of this. Thank you in advance for your cooperation.

[monyx]

You are shooting beyond the camera's design scope.

Oh I thought I taking photographs with it!

It's not really an issue with the lens

Granted one needs to shoot mindful of lens' weakness, but my ED f/2.8 glass performs markedly better (notwithstanding the fringing could be from a combination of blooming or CA ) ergo it is largely an issue with the lens albeit interacting with a particular CCD/optical filter design.
Mark

[gstark]

You are shooting beyond the camera's design scope.

Oh I thought I taking photographs with it!

It's not really an issue with the lens

Granted one needs to shoot mindful of lens' weakness, but my ED f/2.8 glass performs markedly better (notwithstanding the fringing could be from a combination of blooming or CA ) ergo it is largely an issue with the lens albeit interacting with a particular CCD/optical filter design.
Mark

Mark,

Please pay attention. I have highlighted a couple of aspects of what has just been said in order to try to help you ...

May I ask you to estimate what you think the exposure range is that you have tried to cover in your image here? Would you say three stops? Four? How many stops does your camera's sensor cover in any one image? What is the specification for the camera?

[monyx]

FWIW D200...in any case life too short to expend too much on this...I just note that I'm not the only one to find this experience with the 50 1.4D...
http://www.digitalslr.com.au/forum/viewtopic.php?t=10953

[gstark]

I just note that I'm not the only one to find this experience with the 50 1.4D...

Which means that you're now missing not just one, but two points.

Perhaps even more than two points ......

But to get back to the point: do you want to tell me that Big Brudder is good tv because it's popular? If so, why? If not, why not?

It IS an important question in this discussion, but only if you are willing to listen and learn.

[MCWB]

Monyx says he gets better results with a different lens. From a scientific perspective if you keep the same scence, same camera, change lenses and observe any change in image quality then what you're observing is down to more than just the camera's design, because you have controlled for that.

The fact that you still get some CA/blooming/etc with both lenses is, I agree, a limitation of the system used, but the fact that you get different amounts with different lenses means it's not solely a camera design issue (as monyx says, it's likely to be due to both the lens and the camera designs).

[gstark]

Monyx says he gets better results with a different lens.

Hi Trent.

I am only commenting upon the image that Mark has posted here. The one, solitary image that Mark has posted here in this thread.

That image that he has posted shows outcomes that have arisen due to the fact that the objects in the image are well and truly beyond the limitations imposed upon him by the equipment employed. The "issues", therefore, are expected outcomes, given the conditions experienced, and if they're to be described as "issues", then I would respectfully suggest that the issues displayed in this image might be more appropriately described as issues in either technique or user expectations, rather than with the equipment, be that camera, sensor or lens.

Again, for the subject matter being photographed, the result presented is an expected outcome. The only real unknown here is the extent of the aberrations that will be seen, and perhaps a different choice of lens might reduce (or, perhaps, increase) the extent of the aberrations observed.

So too might changing the viewpoint or content of the image, or changing the exposure variables.

That Mark says that he gets better results with a different lens is basically unproven within the context of this image, which is seriously flawed to the extent that what Mark is describing as issues I am saying are simply expected outcomes.

From a scientific perspective if you keep the same scence, same camera, change lenses and observe any change in image quality then what you're observing is down to more than just the camera's design, because you have controlled for that.

Only if you're shooting the exact same subject, from the same PoV, etc. Mark has not presented any evidence that this is the case.

Cheers.