D750 Light Leak videos

[J-see]

I'm going to try and show the confusion of the problem.

Here's the light leak.



Now I tilt it upward a bit more to make the leak disappear. In reality I just wash the upper part out.



Now I remove the distraction from the light leak shot by cutting the upper area that isn't affected. That's all I do here.

 

[BackdoorArts]

It could very well be whatever mechanism switches to DX mode since that position is identical.

This is interesting from 2 perspectives. First, I do not believe there's a mechanism for DX, it's just simply a matter of define which portion of the sensor gets used ("mechanism" something mechanical, so I would expect to hear and audible sound or difference in shutter activation when in DX vs. FX and I do not). Second, if it still appears when the camera is in DX mode then it can't be an issue of light hitting the sensor since DX mode effectively cuts out the portion of the sensor where the line appears.

So, if I'm understanding this correctly and you are able to produce this effect regardless of crop mode then the problem has to be something beyond just optics.

 

[J-see]

I have the cam on a pod, makes it easier. If you get it on live-view, you can turn it off and take the shot, it shows in the shot. I'm not using the viewfinder to get the angle since there I don't see it but then again, I ain't got eagle eyes.

 

[BackdoorArts]

My apologies if this was covered, but I'm assuming this "problem" goes away if you put a lens hood on as recommended when shooting in direct light?

 

[J-see]

This is interesting from 2 perspectives. First, I do not believe there's a mechanism for DX, it's just simply a matter of define which portion of the sensor gets used ("mechanism" something mechanical, so I would expect to hear and audible sound or difference in shutter activation when in DX vs. FX and I do not). Second, if it still appears when the camera is in DX mode then it can't be an issue of light hitting the sensor since DX mode effectively cuts out the portion of the sensor where the line appears.

So, if I'm understanding this correctly and you are able to produce this effect regardless of crop mode then the problem has to be something beyond just optics.

I don't get it in DX mode, the other two show it. I only see a resemblance between the outline of my DX shot when framed and the "block" part of the light leak. I don't know if the cam directs light to one part when switching modes or if it is purely software defined. I might be connecting dots that have no relation to the other.

 

[J-see]

My apologies if this was covered, but I'm assuming this "problem" goes away if you put a lens hood on as recommended when shooting in direct light?

Yes, just a finger above the front of the lens is enough here or using a hand. I don't use the lens hood to make the problem easier to produce, with it requires more searching to find that area where the hood starts to fail.

 

[Eyelight]

Apologize if this is back in the thread somewhere. [MENTION=13090]Horoscope Fish[/MENTION] are you and [MENTION=31330]J-see[/MENTION] using the same lens or same focal length in your effort to reproduce the effect??

 

[J-see]

Apologize if this is back in the thread somewhere. @HoroscopeFish are you and @Jsee using the same lens or same focal length in your effort to reproduce the effect??

This far I produced it with the 18-35mm on the FX and the 10-24mm on the DX. Even with the 35mm 1.8 on both. The D3300 I have to turn upside down to produce the effect. Makes me wonder if the D3300 has different modes too. Not that I'm aware but there the same happens.

 

[J-see]

Using a Nikon 50mm f/1.8G I can cause this effect when using Live View but no matter how hard I try I can't get it happen in the viewfinder. I set my camera on a tripod and switched back and forth between the two modes: Live View clearly shows the dark band... Switch to the viewfinder and the band is gone... Back to Live View and the band re-appears.

No matter what I do, I can't get the banding to appear when using the viewfinder, not even a little. I don't know if this is the case with anyone else, but I've tried this both indoors and out and my results consistent.

....

I tried some more and checked the view-finder until my eyes hurt. Then I tilted the lens up and checked again.

What is interesting is that I also don't see the normal wash-out. The viewfinder is much darker but it also isn't the exact same view that reaches the sensor. Whatever we see, indirect light seems to be able to surpass that on its path to the sensor.

 

[Eyelight]

I tried some more and checked the view-finder until my eyes hurt. Then I tilted the lens up and checked again.

What is interesting is that I also don't see the normal wash-out. The viewfinder is much darker but it also isn't the exact same view that reaches the sensor. Whatever we see, indirect light seems to be able to surpass that on its path to the sensor.

Can you see the part of the image where the shadow line is in the viewfinder or is it past the edge of the view?

 

[J-see]

Can you see the part of the image where the shadow line is in the viewfinder or is it past the edge of the view?

I can't see that in the viewfinder. There is no shadow line, that's the shot as it should be when no indirect light had hit the lens.

When the light is blocked (as it should), it is obvious that what appears to be shadow is the shot as it should be. The lighter part is the problem since in reality, it isn't there.





Btw, I forgot to do the most obvious thing. Turn the D750 upside down.

​

As you can see, the problem isn't the light but not enough wash out because of the block when using normal position. People are complaining that the D750 doesn't let them fully ruin their shots.

 

[Eyelight]

To clarify, if you set the camera where the shadow line shows in live view, is that part of the image visible in the viewfinder or is it cropped off?

 

[J-see]

Later on I'll check if I can reproduce it with my 200mm. I can attach that lens to the pod and turn the cam into any direction without affecting the framed shot. If it works, that should show better what exactly happens.

 

[J-see]

To clarify, if you set the camera where the shadow line shows in live view, is that part of the image visible in the viewfinder or is it cropped off?

I see it in live-view but not in the viewfinder. The viewfinder is much smaller and darker compared but I suspect it not even showing the stray light for some reason. This light doesn't follow the normal path through the lens which may have something to do with it.

It could have something to do with the position of the mirror but regardless what view-method used, it always shows in the shot taken.

 

[J-see]

I put the 200mm on. It takes amazing effort to produce it with a long lens and the light source needs to be just outside of the shot. The effect isn't as pronounced and only occurs when the cam is turned almost upside down. Besides it being a reminder I need to put the cam down and really dust that ceiling, it nicely shows what light can do when hitting the lens wrong.

View attachment 129525





View attachment 129528



View attachment 129531







View attachment 129537

View attachment 129538

 

[Horoscope Fish]

I've pretty much come to the conclusion that, for me at least, this is a non-issue.

Whatever you want to call this -- banding, light-leak, whatever -- I have to work really hard in order to make it appear, it's easy to make dis-appear and, from what I can tell, it's just not worth thinking about. I'll keep my ear to the ground about the issue and if the mystery gets solved, and/or a solution is arrived at, so much the better. Maybe in time my opinion will change and I'll come back singing a different tune, but as of now, personally... I'm over it. I'm simply enjoying my D750 waaaay too much to get my panties in a wad over this bizarre little idiosyncrasy.

EAT MOR CHIKIN!

...

 

[J-see]

I've pretty much come to the conclusion that, for me at least, this is a non-issue.

Whatever you want to call this -- banding, light-leak, whatever -- I have to work really hard in order to make it appear, it's easy to make dis-appear and, from what I can tell, it's just not worth thinking about. I'll keep my ear to the ground about the issue and if the mystery gets solved, and/or a solution is arrived at, so much the better. Maybe in time my opinion will change and I'll come back singing a different tune, but as of now, personally... I'm over it. I'm simply enjoying my D750 waaaay too much to get my panties in a wad over this bizarre little idiosyncrasy.

EAT MOR CHIKIN!

...

Did you try to reproduce it with your other cam(s)? They should do the same but not necessarily when holding them normal.

I'm not bothered about the leak either. It never showed in any shot so it can't be a disaster. But it's a problem I enjoy digging into because of all that wha-wha about this non-issue.

 

[J-see]

The previous showed my hand in the shot so to avoid people thinking I blocked the light, I reshot them. Lens at 90 degrees to make the CP most effective. First without, with, with, without.



​

 

[Eyelight]

[MENTION=31330]J-see[/MENTION] what is the position of the light that causes the effect in relation to the front of the lens and also the angle. Is it almost directly overhead and almost 90 degree?

 

[J-see]

@J-see what is the position of the light that causes the effect in relation to the front of the lens and also the angle. Is it almost directly overhead and almost 90 degree?

With the CP filter the front of the lens is at the center-line below but next to it at around 90 degrees. If that doesn't make sense, it's not too different from the set-up I showed in those shots posted in a previous reply. I made sure here I had the most effect using the CP.