N8´s Major Camera Desing Flaw - Poor Flare Performance

Posted by Vit
Guys, I´ve just received my N8.

Do you know those pale N8 shots that appear from time to time over the net?

I´ve just figured out why.

IT´S NOT ABOUT THE SENSOR.

The bad guy here is that f**king brushed metal finishing around the camera. Under strong light sources, that element directs light into the sensor! God damn those designers!

This particular issue produces a HUGE decrease of quality!

If you approximate your hand to the camera, the scene becomes much better, but that´s indeed an annoying thing to do!

Take a look at my examples. Both were taken before and after placing my finger nearby the camera:

Just look how bad it can become sometimes:

I am testing it throughly, but what I can say is that it´s not that good as I expected it to be.

EDIT: Here are some more samples of the issue. These shots required a whole hand over/behind the camera in order to get rid of this awful effect. Look @ the improvements when it comes both to colour and contrast. That´s unbelievable.

[ This Message was edited by: Vit on 2010-11-06 17:28 ]

Posted by Bonovox
The last shot with the yellow bit down the mirrow

looks terrible. Are you sure that is what it is?? Are you sure your one is just not faulty??

Posted by Vit

On 2010-11-06 14:58:51, Bonovox wrote:
The last shot with the yellow bit down the mirrow

looks terrible. Are you sure that is what it is?? Are you sure your one is just not faulty??

I am pretty sure it´s not faulty.

When I put my finger over it, the effect vanishes. Just like the other shot.

Here you can even see the tip of my finger getting into the frame:

Now with the finger over the camera:

[ This Message was edited by: Vit on 2010-11-06 14:10 ]

Posted by Del
I haven't had this sort of issue with my N8, are you sure your one is not faulty ?

Posted by Vit

On 2010-11-06 16:02:44, Del wrote:
I haven't had this sort of issue with my N8, are you sure your one is not faulty ?

What kind of fault would it be?

Flare is a common issue with any lens. Some fare better, some fare worse. It doesn´t seem to be a fault.

The issue is not always present. It´s there only in some angles, but its performance in this regard is worse than pretty much any other cameraphone I´ve owned.

[ This Message was edited by: Vit on 2010-11-06 15:30 ]

Posted by Del

On 2010-11-06 16:08:50, Vit wrote:

On 2010-11-06 16:02:44, Del wrote:
I haven't had this sort of issue with my N8, are you sure your one is not faulty ?

What kind of fault would it be?

Flare is a common issue with any lens. Some fare better, some fare worse. It doesn´t seem to be a fault.

[ This Message was edited by: Vit on 2010-11-06 15:10 ]

I haven't got a clue what sort of fault it could be but not one of my shots have the yellow line down them and to be honest I haven't noticed any flare in my shots either, but then again I'm no photo expert I just tend to point and shoot.

Posted by Vit

On 2010-11-06 16:27:52, Del wrote:

On 2010-11-06 16:08:50, Vit wrote:

On 2010-11-06 16:02:44, Del wrote:
I haven't had this sort of issue with my N8, are you sure your one is not faulty ?

What kind of fault would it be?

Flare is a common issue with any lens. Some fare better, some fare worse. It doesn´t seem to be a fault.

[ This Message was edited by: Vit on 2010-11-06 15:10 ]

Well, are you sure you´ve tested it in a variety of shooting angles like I did?

The effect is present in some shooting angles, not all of them. That´s why I am pretty sure it´s not a HW fault.

Posted by edwardob
@vit
do you mean the little polished finished around the lens glass??

could be sorted with a little black model paint...although not ideal for a 400euro phone
but it's a solution

Posted by Del

On 2010-11-06 16:32:33, Vit wrote:

On 2010-11-06 16:27:52, Del wrote:

On 2010-11-06 16:08:50, Vit wrote:

On 2010-11-06 16:02:44, Del wrote:
I haven't had this sort of issue with my N8, are you sure your one is not faulty ?

What kind of fault would it be?

Flare is a common issue with any lens. Some fare better, some fare worse. It doesn´t seem to be a fault.

[ This Message was edited by: Vit on 2010-11-06 15:10 ]

Well, are you sure you´ve tested it in a variety of shooting angles like I did?

The effect is present in some shooting angles, not all of them. That´s why I am pretty sure it´s not a HW fault.

I've just just looked through all the shots I have taken with my N8 and there is no flare or yellow line ?

Posted by Vit

On 2010-11-06 16:43:44, edwardob wrote:
@vit
do you mean the little polished finished around the lens glass??

could be sorted with a little black model paint...although not ideal for a 400euro phone
but it's a solution

Yes, that finishing is the greatest villain of the whole story.

About your suggestion, it´s simply not worth the risk.

On 2010-11-06 16:45:06, Del wrote:

I've just just looked through all the shots I have taken with my N8 and there is no flare or yellow line ?

Good for you, then.

[ This Message was edited by: Vit on 2010-11-06 16:00 ]

Posted by etaab
Maybe im stupid but will someone explain to me how the phones paint job affects picture performance ? and then by sticking your finger in the shot improves the images ?

eh !?!

Posted by Bonovox
That's what I thought

Posted by jake20
Hi Vit,
I will have to do some more testing, but I don't think I have had this problem either.. definitely nothing like that yellow line in the picture.
I have a green N8 also, so its kind of bright.

I will try to take some more shots to try and reproduce your issue, but I don't think i am having this problem.
But I know you know what you are talking about when it comes to taking pictures.. so I am not questioning what you are seeing.

Its possible I have just not taken a shot under the right lighting to notice this problem.
How is the best way i can re-produce this issue?

[ This Message was edited by: jake20 on 2010-11-06 21:27 ]

Posted by etaab
I think what Vit is getting at is the silver brushed metal around the casing that then turns into the camera glass.

Personally i see what hes getting at, but i dont think its responsible. My N8 had a few lens flare issues when shooting into the light but i know that wider angle lenses are more susceptable to such an effect.

[ This Message was edited by: etaab on 2010-11-06 21:10 ]

Posted by jake20
Took this with Nokia Panorama app.. app is very basic, so no options really.. hope a better one comes along

[ This Message was edited by: jake20 on 2010-11-06 21:37 ]

Posted by jake20
Vit have you applied these hacks to get bigger photos and 30 FPS video?
I dont have a dev cert, and dont really feel like posting my IMEI on the internet, or i would of tried them already.
But i really do want the 30fps video..

Link text...

Posted by Bonovox
@jake20 that is a stunning panorama shot

Posted by Vit

On 2010-11-06 22:08:19, jake20 wrote:
Hi Vit,
I will have to do some more testing, but I don't think I have had this problem either.. definitely nothing like that yellow line in the picture.
I have a green N8 also, so its kind of bright.

I will try to take some more shots to try and reproduce your issue, but I don't think i am having this problem.
But I know you know what you are talking about when it comes to taking pictures.. so I am not questioning what you are seeing.

Its possible I have just not taken a shot under the right lighting to notice this problem.
How is the best way i can re-produce this issue?

[ This Message was edited by: jake20 on 2010-11-06 21:27 ]

Hi, Jake!

Well, that shot with the whole yellow line was the only one I´ve got from that kind, and I needed to 'seek' for that 'magic spot'. All others also have strong flare only @ certain angles, so it´s not an ever present effect.

Try to vary the angles when shooting a scene with strong light sources coming from both sides and from above and below. Your pano shot, for instance. The last pic from the right shows a strong loss of contrast and dynamic range due to flare.

@ etaab: Fisrt of all, I really do not know where you saw 'paintjob' in my messages.

Wide angle lenses have critical flare performance, that´s true, but I guess that in the N8 it is even more critical sometimes.

I´ll be posting some of my shots @ the 'post your pictures' thread.

Posted by Vit

On 2010-11-06 22:41:54, jake20 wrote:
Vit have you applied these hacks to get bigger photos and 30 FPS video?
I dont have a dev cert, and dont really feel like posting my IMEI on the internet, or i would of tried them already.
But i really do want the 30fps video..

Link text...

I have them signed, but I´ve not tried them out. I´m planning to use the 97% quality .sis, but I am afraid of messing with video fps. I saw the video sample posted by hx and that was simply amazing. 11Mbps of video bitrate. Impressive stuff indeed.

Get you certificate @ opda. Their site do not have tricky links or scripts. I´ve got mine yesterday.

Posted by Vit

On 2010-11-06 22:09:08, etaab wrote:
I think what Vit is getting at is the silver brushed metal around the casing that then turns into the camera glass.

[ This Message was edited by: etaab on 2010-11-06 21:10 ]

Look @ your own shots:

LOOK CLOSER @ THESE SHOTS: THE STRONGEST LIGHT SOURCE COMES FROM THE RIGHT, AND THE FLARE IS SHOWING AT THE LEFT. HOW ODD IS THAT? This cleraly shows that the light is getting reflected by some undesired agent, don´t you think? That highly reflective brushed surface is a serious candidate for that.

See what I am saying?

Try to take them with some of your fingers blocking the sunlight. You´ll be amazed by the difference that makes.

Have you ever heard of lens hood? That´s where the idea of 'blocking fingers' come from.

[ This Message was edited by: Vit on 2010-11-07 15:58 ]

Posted by jake20

On 2010-11-07 16:48:42, Vit wrote:

does 30FPS video take up a lot more storage space than 25fps?

Posted by Bonovox

On 2010-11-07 16:53:57, Vit wrote:

On 2010-11-06 22:09:08, etaab wrote:
I think what Vit is getting at is the silver brushed metal around the casing that then turns into the camera glass.

[ This Message was edited by: etaab on 2010-11-06 21:10 ]

[ This Message was edited by: Vit on 2010-11-07 15:58 ]

Perhaps you should scratch that area to make it less shiny. But if that is the case that's not good I guess Nokia may have to release newer models without this & give replacements if they see it as a problem

Posted by jake20
Guys,
Go here --> http://conversations.nokia.com/2010/11/05/interview-with-damian-dinning-nokia-n8-imaging/
Damian Dinning is answering questions on the N8 camera right now..Post any questions you have quickly while he is still around!

[ This Message was edited by: jake20 on 2010-11-07 21:51 ]

Posted by voda_jon
@jake20 yeh it uses a hell of a lot more storage... i took a 5min firework video and i have the full 100% image mod with 30fps vid and it come in at just under 500mb!!! so about 100mb per min but quality is great especially in the images!!!

Luckily for me i live in the uk where lens flare tends not to be a big issue day to day and when it is am too busy enjoyin the sun to care about it appearing in my images.

Posted by DarkKrypt
'the ring' needs to be like satios

not saying n8 is a bad phone my father in law loves it espesh over his iphone 3gs.
hes never going down the birdshi-t way again
and i like it too:) great design nice features etc.

Posted by Vit

On 2010-11-07 22:50:36, jake20 wrote:
Guys,
Go here --> http://conversations.nokia.com/2010/11/05/interview-with-damian-dinning-nokia-n8-imaging/
Damian Dinning is answering questions on the N8 camera right now..Post any questions you have quickly while he is still around!

[ This Message was edited by: jake20 on 2010-11-07 21:51 ]

Here´s the message I left there:

Hello, Damian.

My big question is: why limiting its shutter speed to 1/5s?

I understand that 1/5s in Night Mode is a big improvement over the normal mode, but at the same time it has a slightly slower Shutter Speed, it also cranks up the ISO.

I will not discuss how important it is for the general user, but I guess that a SW implementation of an Advanced User Menu would be greatly welcome, and doesn´t represent a big challange for your team.

The average user would never use it, but I guess that this would unleash the power within the 'biggest sensor ever fitted in a mobile'.

Look at the contenders from the past: Satio and Pixon12, for instance.

The Satio enables 1s SS and ISO 100-160 in its Twilight Landscape Mode.

The Pixon12 enables 1s SS and ISO-50 in its Fireworks Mode.

Some might like the answer:

'It doesn´t have slower SS because it doesn´t have a tripod mount.'

IF THAT´S TRUE, WHY HAVE YOU FITTED A 20s SELF-EXPOSURE TIMER IN IT? Where would you leave it if it doesn´t sport a tripod mount?

Besides that, it´s pretty much annoying having to enter the gallery everytime I want to zoom at the picture I´ve just taken and then returning to the camera interface to take another one.

Another big question regards the video mode: recently, the HX modder has managed to increase both fps and the video bitrate to 30fps and 11Kbps (previously 25 fps and 6Kbps). His sample video looks truly amazing. Are these changes secure Hardware wise?

So, my suggestions are:

- Enabling an ADVANCED USER MENU where we can choose manual Shutter Speeds and Manual ISO (100,200,400,800);

- Enabling zooming in the revision window;

- Embed the EV ruler within the frame. Change EV position by tapping at an arrow, not by changing the selector position (it´s too tiny);

- Tap to change Modes and Flash settings, instead of tapping to enter a menu and then selecting a setting;

- Tap-to-focus;

- Autofocus in Video Mode;

- Increase the JPEG quality to 97%.

THANKS FOR YOUR TIME.

Posted by jake20
Vit,
I agree with everything you say here.. but you may of given Damian too much here. too many requests.
I think he will maybe not respond to too much criticism.

I posed him with 3 questions and he answered them.. basically his answers are..

1. 30FPS video is coming soon, and they didn't include it because it wasn't 100% stable yet.
2. Update to Panorama app is coming soon
3. They are looking into HDR, but can't guarantee anything

[ This Message was edited by: jake20 on 2010-11-08 16:39 ]

Posted by mrjulius
maybe in the next model

Posted by jake20
Vit,
I see Damian answered you.. this is good news, and he seems to also agree and already aware of everything you posted.
When the updates come it should shut up all the Nokia Haters here (see post above)

Posted by mriley
What was his reply..?

Posted by jake20

On 2010-11-08 20:31:15, mriley wrote:
What was his reply..?

Thanks for your various comments, we are looking at many areas which overlap with your requests. no promises though.

One point the video bit rate has not been changed in the hacks, it already allows up to 12mbps out of the box. But this is dynamic, it depends on the amount of detail in the scene.

re 30fps I already answered that along with compression in the original interview.

br

D

Posted by etaab

On 2010-11-08 17:14:15, jake20 wrote:

1. 30FPS video is coming soon, and they didn't include it because it wasn't 100% stable yet.

Does that mean they're going to add the same functionality that otherwise you'd need to use the hacks to obtain ? such as the 100mb per minute files etc ?

Posted by mlife
I believe the bad flare issue is indeed caused by the silver ring and is easy to dupliate... in the photo below you can clearly see a curved shape flare which IMO is the silver ring around the lens (my N8 is orange).

If I simply place my finger to the right of the lens (seperating it from the light) you get this...

*my finger entering the camera lens to left is only to show HOW MUCH light is reflecting right there.....

Posted by Bonovox
Do you think if Nokia were or are aware of this would they see it as an issue or not?? Would they release future N8's with no silver outline?? Would they replace existing models or would that be far too expensive for them?? I guess it could put their long awaited flag ship N8 in a bad light(no pun intended)

[ This Message was edited by: Bonovox on 2010-11-11 14:26 ]

Posted by mlife

On 2010-11-11 15:26:02, Bonovox wrote:
Do you think if Nokia were or are aware of this would they see it as an issue or not?? Would they release future N8's with no silver outline?? Would they replace existing models or would that be far too expensive for them?? I guess it could put their long awaited flag ship N8 in a bad light(no pun intended)

[ This Message was edited by: Bonovox on 2010-11-11 14:26 ]

I highly doubt they will do anything about it.... my C905a does the same thing and once your aware of the issue the solution is simple. A) try not to shoot toward bright light (ie, keep sun at your back) unless your intending to add flare to your image.. or B) just use your finger/hand to block the sun/light in those situations.... Not really a HUGE issue IMO

Posted by jake20
They most likely intentionally made this ring a brushed metal surface for a reason.. it probably brings in more light in low light situations as well.. which is a good thing i guess.

But from what what I have seen so far with Nokia, is they will delete any threads on their support sites which call them out or put them in a bad light.

Posted by false_morel
Guys, I'm not very sure about this, but the way I see it, those excessive flares are a downside of the wide lens optics rather than that sliver ring around the lens!

Actually, physically, or geometrically, teh ring is bended away from the lens. This means it should reflect light away from the lens not vise-versa! At extreme cases, a light ray would be reflected with 0° angle, but never negative angle towards the lens..

This is how I see it..

And actually I find it really awkward for the team developing the camera to oversee this flaw if it exists!

And at the end of day, any camera, specially with wide-angle lens, will suffer from those flares at certain angles when facing a bright light source!
Of course, the question here is whether that ring is helping worsening the situation, but in my opinion, it should be rather helping improving the conditions.
And that finger-shading effect that helps remove those flares, is actually stopping excessive light from entering the lens rather than stopping it from refelcting off the ring..

About the position of the flares, it doesn't have to be on the side of the light-source, specially if the sun is that source..

Correct me if I'm wrong..

My two cents.

Posted by Bonovox
@mlife that photo with the flare is quite excessive. I have seen lens flare before but nothing that bad

that's a design flaw imo that Nokia have not realised. Having to stick your finger in front of the lens is just crazy

[ This Message was edited by: Bonovox on 2010-11-11 17:41 ]

Posted by etaab
I agree with false_morel, i dont think its a design flaw at all since the silver rim is pointed outwards from the lens. I dont see how it could reflect light back in.

I posted in the Satio vs N8 thread when i received my first N8 that it was more prone to lens flare due to its wider angle lens. Its a no brainer for me.

I imagine putting your finger or hand around the lens to shield it from excessive light is like using a car sun visor, or when looking into the distance on a sunny day you put your hand across your forehead to shield your eyes from light in order to stop the same effect with your own human eye. No ??

For me, i think id rather just not shoot into the sun or any other light source - which naturally a good photographer wouldnt do anyway unless he was going for an artistic shot.

[ This Message was edited by: etaab on 2010-11-11 20:48 ]

Posted by jake20
a little off topic..

are any of you guys using any kind of screen protector for the camera lens? which also may further reduce glare..

I have a nice Nokia CC-1005 green silicone skin (is nearly an identical color match of my Green N8) which further indents the camera lens so its not touching anything when i put it down, so I don't think i really need any extra protection.

Was curious to see if you guys are using anything on the camera glass for protection..

Posted by mlife

On 2010-11-11 21:47:26, etaab wrote:
I agree with false_morel, i dont think its a design flaw at all since the silver rim is pointed outwards from the lens. I dont see how it could reflect light back in.

Easy, Angle of incidence = Angle of reflection.

the blue line on the left is regular light.... it would hit the silver rim and go across the lens.....
the red line is stray light (as light comes from EVERY angle)... when light reaches it destination it has limited choices.... go through the object, scatter (in many directions) or reflect off in an equal and opposite direction... glare is created when the stray light reflects off in such a way that it illuminates the surface of the glass.....

This is what makes lens hoods (and out finger) so effective in reducing glare.... if you block the light that would skim across the glass/lens from the outter edges you can reduce or totally eliminate that effect as in my very poor illustration below.

[ This Message was edited by: mlife on 2010-11-12 00:29 ]

Posted by false_morel
You simplified things too much!
And you missed some major points.

Anyway, going with your simplified basic explanation, here the points you missed:

In the picture above are two light sources, "a" and "b".
Source "a" emitting three rays, and "b" two rays.

The perpendicular black line is the Normal line to the ring's planar area.
Given the necessary conditions, those rays should reflect at the same angle they make with the Normal.

Orange1 and Red1 relflect away from the lens.
Orange2 and Red2 go directly into the lens and refract, probably causing not only flares but also artifacts.

Orange3 is our "special" ray. It reflects from the ring into lens.

Now, the issue here, for a source to emit such rays that reflect into the lens, two conditions should be met:
- That ray hits the outer region of the Normal. In this case, O3 hits the left side of the Normal.
- It should hit it at an angle greater than 45°.. Depends however on the position of the spot hit on the ring, and the curvature of the ring as well.. It could need up to 60° to make it through the lens for instanace..

However, to meet those two conditions, teh source must be within the view, in other words visible in the viewfinder! Which means it's already resulting in some excessive amount of light in and flares already there..

In the other case of Source "b", the source shouldn't be visible to the camera, but could still result in some flares (Etaab's photos!!)..
But not caused by ring reflection..

However, capturing photos whereas the light source isn't producing rays directly into the lens shouldn't result in any flares. This happens when one makes sure that source is well maintained by the right angle of view..

Posted by mlife
@ false_morel, You now contridict yourself.... in this post you say

but then you come back telling me I miss important points only to over explain the same exact thing I just said in an extremely convoluted way? You also show a diagram totally contradictory to your statement "but never negative angle towards the lens" .... how is toward the LENS a "negative angle" anyway? Its just a reflection from the silver ring to glass or across the glass itslef, no need to make more of it than it is..... its simply A POOR IDEA to have a silver reflective surface by the lens. Its not 100% the issue (I understand this) but is certainly don't help at all.

Posted by rikken

On 2010-11-12 06:30:45, mlife wrote:
. . . . its simply A POOR IDEA to have a silver reflective surface by the lens.

This seems obvious. If I had a N8 and experienced flare problems, I would try a black marker to color the silver ring

Posted by false_morel

On 2010-11-12 06:30:45, mlife wrote:
@ false_morel, You now contridict yourself.... in this post you say
but then you come back telling me I miss important points only to over explain the same exact thing I just said in an extremely convoluted way? You also show a diagram totally contradictory to your statement "but never negative angle towards the lens" .... how is toward the LENS a "negative angle" anyway? Its just a reflection from the silver ring to glass or across the glass itslef, no need to make more of it than it is..... its simply A POOR IDEA to have a silver reflective surface by the lens. Its not 100% the issue (I understand this) but is certainly don't help at all.

You missed the trick again..

When I said that there is no way for light to bounce at negative angle and into the lens, I was referring at teh case of Source "b" illustrated in the drawing I posted. Same as what happened in teh two photos of Etaab for instance.. The source isn't within the angle of view!

However, if you have some bright light source within the angle of view of the camera, it will result in flares anyway..
Now, you can argue that the ring may make it even worse. Ok, in this case I could agree. But there's no point here blaming the ring for flares as those would already be there!

Then, as to the simplification I hinted to.. You missed that the material the ring made of isn't a perfect reflecting one!
And you missed the curving part of it..
There are many given conditoins here if considered would lead for the most of light not ot be refeclted at teh first place!

Flares mainly occur of excessive light entering the lens directly and refracting. Light bouncing off objects, even extremely near objects, shouldn't be a problem!

That's why I said I'm not very sure in my first post. There's many diverse aspects to consider and you simplified things too much.

In conclusion, if that ring does have some negative effect, it's due to only when the camera facing a light source, which isn't that wise to do, and the effect is minimal in comparison to the rather natural flare effect taking place at that condition!

Again, notice the "if's"...

Posted by Vit

On 2010-11-11 18:04:20, false_morel wrote:
Guys, I'm not very sure about this, but the way I see it, those excessive flares are a downside of the wide lens optics rather than that sliver ring around the lens!

Actually, physically, or geometrically, teh ring is bended away from the lens. This means it should reflect light away from the lens not vise-versa! At extreme cases, a light ray would be reflected with 0° angle, but never negative angle towards the lens..

This is how I see it..

And actually I find it really awkward for the team developing the camera to oversee this flaw if it exists!

And at the end of day, any camera, specially with wide-angle lens, will suffer from those flares at certain angles when facing a bright light source!
Of course, the question here is whether that ring is helping worsening the situation, but in my opinion, it should be rather helping improving the conditions.
And that finger-shading effect that helps remove those flares, is actually stopping excessive light from entering the lens rather than stopping it from refelcting off the ring..

About the position of the flares, it doesn't have to be on the side of the light-source, specially if the sun is that source..

Correct me if I'm wrong..

My two cents.

A Sharp Edge doesn´t reflect the light evenly.

[ This Message was edited by: Vit on 2010-11-12 15:51 ]

Posted by Vit

On 2010-11-11 14:57:06, mlife wrote:
I believe the bad flare issue is indeed caused by the silver ring and is easy to dupliate... in the photo below you can clearly see a curved shape flare which IMO is the silver ring around the lens (my N8 is orange).

If I simply place my finger to the right of the lens (seperating it from the light) you get this...

*my finger entering the camera lens to left is only to show HOW MUCH light is reflecting right there.....

Good (and also bad) to know that I am not the only one who thinks that.

People that say it´s merely a lens issue don´t seem to know the issue that well.

I´ve had a Pixon12, which has 30mm of focal lenght. I´ve never seen such a great amount of lens flare with it.

Besides that, when we talk of critical lens flare with wide angle, we usually talk about super wide lenses. For instance, 14mm lenses.

28mm is not that wide for this lens to behave that badly.

That 'ring' has a sharp edge, and this kind of edge does not reflect the light evenly.

My guess is that it has been a designer´s solution. I don´t think it has a functional hole.

[ This Message was edited by: Vit on 2010-11-12 15:59 ]

Posted by false_morel
Vit, could you shed some more light on your sharp edge theory?
You don't have to go all geeky like mlife and I did, illustrating everything. Just some more words would do..

But again, I may agree that the ring could worsen the flare effect only if some bright light source was within the frame of the camera! Also, at certain angles, not all the time..

Otherwise, in case of Etaab's two photos, where the sun was out of the frame, there should be no way the ring could reflect some light into the lens!
In this case, the flares there are a mere wide lens downside..

Posted by Vit
At both the bottom and the top of that surface, sharp edges may not reflect the light evenly, giving way to diffuse reflection.

If that lower part were convex and the upper part were concave, then we would guarantee that nothing would come into the lens, but due to the finishing job imprecisions that can be present, the light might not reflect evenly there, and we could not precise to where light rays are directed.

Besides that, you´ve also missed something in your analysis.

First of all, you´re assuming that the inclination angles that those reflective surfaces form with any perpendicular line to the reference plane coincide with half the viewing angle, and that is mostly not true.

Secondly, you also haven´t taken the distance between that plane and the sensor into account.

Thus a light source may well be out of the range of the lens and still have an effect at the opposite side of the frame.

Take a look at these pictures:

Those two etaab´s photos may well have been affected by this brushed metal ring.

[ This Message was edited by: Vit on 2010-11-12 20:23 ]

Posted by jake20
ok Vit are you a talented painter? just paint that ring black

have you tried 30FPS video yet?