Strange line in image

[Stagecoach]

Looking just to the right of the blue light I can see an area with a defined vertical edge in the sky

The only thing I can think of at present is a 'reflection' in light mist/haze in the area. Nothing has been done to the image in PP that would cause this.

Any other ideas?



Grahame

[Geoff F]

Strange effect to be sure. Also there are lines across the water which are joined at the inner edge, with rounded corners, and appears to be behind the blue light reflection.

Is that a shadow coming from the left side or maybe something on the sea bed?

Could the cloud smudge like line be smoke rising?

[Stagecoach]

Strange effect to be sure.

That's what I thought Geoff and it's also evident in a second shot I took at another ISO.

Also there are lines across the water which are joined at the inner edge, with rounded corners, and appears to be behind the blue light reflection.
Is that a shadow coming from the left side or maybe something on the sea bed?

Within the area of the blue light reflection and below there are reflections from the apartment stairway lights and the darker lines are due to hand railings that go along that bit of wall you can just see bottom left. The dark square (now a diamond shape was from a rather large no parking sign where I was parked)

Could the cloud smudge like line be smoke rising?

To me it is just too straight. The lights in the distance look fuzzy to me which suggests haze but I have to admit when I shot this I had moved the camera/tripod from what I had actually been shooting and did not re-focus as it was already manually focused for the stars.

[William W]

. . .To me it is just too straight. . .

The straightness piqued my brain.

It could be light "in the scene": but don't discount that a lot can happen when light is bouncing around inside the lens (and lens filter?) for twenty seconds.

What Lens?
Any Filter?

WW

[Stagecoach]

The straightness piqued my brain.

It could be light "in the scene": but don't discount that a lot can happen when light is bouncing around inside the lens (and lens filter?) for twenty seconds.

What Lens?
Any Filter?

WW

The lens was the Nikon 16-35mm f/4 G ED Bill and is fitted with a Hoya Skylight 1B (for protection).

Here's a crop of the area with the PP pushed to emphasise it.

[Manfred M]

Grahame - I virtually always remove any filters from in front of my lens when taking night shots. While optical coatings on the lens elements remove unwanted reflections quite well, any filter including ones with anti-reflective coatings will introduce strange reflections in night shots, especially when there are strong light sources in the scene like this one.

[Stagecoach]

Grahame - I virtually always remove any filters from in front of my lens when taking night shots. While optical coatings on the lens elements remove unwanted reflections quite well, any filter including ones with anti-reflective coatings will introduce strange reflections in night shots, especially when there are strong light sources in the scene like this one.

Manfred, I generally do remove the filter when taking serious shots (those that I know that I want to produce a finished good image) but not when working near sea water.

Over the past couple of weeks I have taken loads of night shots primarily experimental for a future project, with this lens at 16mm and filter and whilst a few of them have exhibited obvious reflections from nearby light sources they have all been of a shape which you can say 100% that was due to a point light source.

The strange thing here is the vertical straightness of the difference between light and dark area.

Another thought I have had is that it's caused by intense lighting along the road in front of the building (you see the side going to the back here), but I am shooting in an area at the end of a small service road where this light is not shadowed by the building. The building is the hotel I posted a few days ago.

Hopefully tonight if the weathers good I can go back to the same location and take a few more shots with and without filter for the purpose of elimination.

[Manfred M]

The more I look at the image, the more I wonder if something else has happened. The exposure on the left side of the image looks different than the right side. The line looks to be vertical, so I suspect the filter is not involved in creating this phenomenon.

[Stagecoach]

The more I look at the image, the more I wonder if something else has happened. The exposure on the left side of the image looks different than the right side. The line looks to be vertical, so I suspect the filter is not involved in creating this phenomenon.

Exactly.

It's almost as if two images exposed slightly differently have been joined at that line just to the right of the blue light

Maybe a blanket of mist away from the shoreline with two different light intensities hitting it?

[William W]

The lens was the Nikon 16-35mm f/4 G ED Bill and is fitted with a Hoya Skylight 1B (for protection).

Here's a crop of the area with the PP pushed

(EXIF noted. Shot was pulled at F/5.6 (max Lens Aperture = F/4)

Thanks for the enhancement. That's helpful.

My theory is Ghost Image from building wall and edge of sidewalk along the water.

Ghost Images are reversed and inverted - noted a HORIZONTAL LINE in the sky (my purple lines indicate).

(only) One stop down from Max Aperture, especially on UWA lens with Filter when shooting High Contrast Scene on Dark Palette are all the necessary ingredients to make a Ghost Image.

It (the Ghost Image) might come and go depending upon your Camera Viewpoint, even if you don't stop down any further or remove the Filter.

Really difficult to see any not extremely bright Ghost Image through the Viewfinder or even in Live View. Even difficult to see on ground glass.

Easiest Ghost Images to see in Viewfinder are those which are really bright and appearing on the darker areas fo the Scene's palette.

Rationale here -



WW

[Stagecoach]

Thanks for this assessment Bill,

(EXIF noted. Shot was pulled at F/5.6 (max Lens Aperture = F/4)

Thanks for the enhancement. That's helpful.

My theory is Ghost Image from building wall and edge of sidewalk along the water.

Ghost Images are reversed and inverted - noted a HORIZONTAL LINE in the sky (my purple lines indicate).

I shall do some research on the internet on Ghost Images, it is something I have not come across before.

(only) One stop down from Max Aperture, especially on UWA lens with Filter when shooting High Contrast Scene on Dark Palette are all the necessary ingredients to make a Ghost Image.

It (the Ghost Image) might come and go depending upon your Camera Viewpoint, even if you don't stop down any further or remove the Filter.

Really difficult to see any not extremely bright Ghost Image through the Viewfinder or even in Live View. Even difficult to see on ground glass.

Easiest Ghost Images to see in Viewfinder are those which are really bright and appearing on the darker areas fo the Scene's palette.

The only additional thing I have just noted is that of the two images I shot which were approx 40 seconds apart one shows the 'horizontal' line as you have highlighted with the purple line and the other does not appear to. I'll put them both through PP together so they have equal adjustments.

Looking at the weather it's unlikely I'll get a chance tonight to try and replicate things.

[Stagecoach]

An update ..........................

I PPd the two images identically I had shot some 40 seconds apart at different ISOs (100/200) and could not replicate the horizontal line Bill pointed out on one of them, but neither could confirm if this was a 'cloud' line that had moved in that 40 seconds.

Unfortunately I was unable to undertake further tests at the same spot last night due to weather.

Today I excitedly unpacked a brand new toy, fitted it to the camera and rattled off some shots to get used to having no aperture indication and just manual focus

Sitting down to review them on the LCD I then noticed this !



Before I had taken the shots in this post I had been shooting the milky way with the viewfinder shutter closed. I had opened it to frame these shots, or so I thought. Even with it closed to the extent above I did not detect that whilst rattling off test shots with my new lens.

So I'm now considering that light entering through the viewfinder may have caused the problem, the slight difference in its appearance between the two images possibly caused by me standing in different positions between shots.

[William W]

Thanks for the update. I reckon that you are onto a very likely possibility.

Canon supply (or used to supply) a rubber eye piece cover attached to the Camera Strap.

This is to be used to block out light entering through the Viewfinder's Eyepiece, during long exposures -



WW

[Manfred M]

Thanks for the update Grahame.

I on those occasions I've forgotten to close off the eyepiece (my camera has the same type of mechanical blind as your camera has), I had not noticed this effect, even in the night shots. The only issues I've run into is some exposure issues where the light leaking in through the viewfinder causes issues.

I'm trying to figure out the mechanism as to how this problem would manifest itself, as the mirror chamber in the camera has surfaces to suppress stray light. I'm looking forward to reading about what your experimenting turns up.

[Stagecoach]

Thanks for the update. I reckon that you are onto a very likely possibility.

Canon supply (or used to supply) a rubber eye piece cover attached to the Camera Strap.

This is to be used to block out light entering through the Viewfinder's Eyepiece, during long exposures -



WW

No problem Bill.

I seem to remember one coming with the camera but now I have fitted the eyecup which was to primarily keep my head from touching the camera the lever for actuating the finder shutter is not so easy to get at in the dark.

What I did the other night was to make and use a fantastic gadget that simply slips over the eyecup.

The prototype is manufactured from a cigarette packet with the flip top cut off. On one face I have then cut a slot just wider than the inner diameter of the eyecup. It's slips on and off effortlessly and hangs on the top tripod leg lever when I want to look at the LCD.

I have spotted a small plastic hand lotion bottle amongst the other half's bathroom rubbish and have my eye on it to make a production model complete with cord and clip that will be attached to the tripod

[Stagecoach]

Thanks for the update Grahame.

I on those occasions I've forgotten to close off the eyepiece (my camera has the same type of mechanical blind as your camera has), I had not noticed this effect, even in the night shots. The only issues I've run into is some exposure issues where the light leaking in through the viewfinder causes issues.

I'm trying to figure out the mechanism as to how this problem would manifest itself, as the mirror chamber in the camera has surfaces to suppress stray light. I'm looking forward to reading about what your experimenting turns up.

I'm not convinced this was the cause Manfred but thought it important to mention.

My only previous experiences with light coming through the viewfinder were when the shutter was fully open and I was doing long exposures using a big stopper. I also found at that time through testing that the result was very dependent upon the direction of the light source.

[William W]

I'm not convinced this was the cause Manfred but thought it important to mention.

Neither am I.

And, for clarity I am not convinced it is a Ghost Image, either.

The thing is, we might not ever know what it is - but at the least the conversation fleshes out some 'best practice' objectives to lower the risk of issues happening.

Puzzles like this can drive (me) people mad.