5DMkII reflections in picture

[Richard Dickins]

Meanwhile, back on topic, I have done some more controlled experiments this morning.

Conclusion:

It's the 5DMkII in portrait mode.

My 5D does not show this, my 1D3 does not show this, and I have tried 24-70 f2.8L, 70-200 f2.8L and 50mm f1.4 lenses. All show the same internal reflection, regardless of filter or hood.

Here's what I did:

This is my overall scene - basically a reasonably dark-ish subject, but with a bright object outside the field of view of the lens. Here's the scene zoomed back a bit:



Next, I mounted my 70-200 f2.8L, with filter and hood, onto a tripod, at 70mm I can only see the wall section, not the window.

5D2 image:


then just changing the camera to the 5D and altering nothing else:


Settings being ISO 100, f2.8, 1/40th @ 70mm

For verification, I put on the 50mm f1.4 lens, no filter, no hood, handheld:
5D2:

5D:


Looking closesely at the way the reflection is curved on it's left side, I suspect that if the hood was a bit longer it would not happen...BUT.. these reflections do not occur on the 5D.

Also, these reflections only occur when the mirror is up, they are not detectable through the viewfinder - which is a major problem as you don't know they have happened until you review the images (or use live-view).

These reflections do not occur in landscape mode, only in portrait mode.

So, why the difference between the 5D and the 5D2 ?

I am going to have to be very much more aware of what is outside my field of view when using the 5D with any lens now. Or is it a fault with my 5D2?

Comments...?

[Paul_F_Caldwell]

It's interesting to note, that I got the red flare with my 5D MKII in landscape mode. I have shot it only once since with a similar sun situation and didn't get the same reflection issue. I have yet to get back to a true sunset situation.

Paul Caldwell

[drew]

Interesting, Richard. No idea what could be causing this.

But, have you tried artificially extending the lens hood as you suggest- to see how far out you have to go to eliminate the unwanted reflections. Maybe grab some black construction paper and curl it around the end of your hoods and tape it together.

Ultimately- to answer your question about whether it is a camera specific defect, you will want to try the same thing with another 5D MKII.

[Richard Dickins]

I'll certainly give that a try Drew, although I suspect that the hoods on the lenses are just the right size for a Full frame camera - extending them may encroach on the image.

I'll give it a whirl in the morning when the sun comes out. If the sun comes out! Actually, any light source will do, I saw a reflection of one of my monitors while fiddling about the other day. Sigh!


Paul - In my tests, I was portrait with a bright object to the right. But, in landscape mode, that would be the same as having a bright area below the field of view - it would give the same effect. So, can you remember if there was some kind of bright object just below your field of view in the sunset shots you had?

[Paul_F_Caldwell]

On that evening I would have been either slightly below the light or almost even, not above it.

Paul Caldwell

[Ross Becker]

Richard
In your scene, you have the bright area to the right & the camera rotated anti-clockwise. The image circle will project some bright light beyond the sensor onto the folded up mirror assembly on the now left (pentaprism) side of the camera. I suspect that the reflection is coming from the folded mirror assembly, therefore not visible in the viewfinder as the mirror is down then.
You could check this by taking the same photo with the camera rotated clockwise so the mirror assembly is on the right side of the camera and the bright part of the image is on the floor of the camera (now on the left).
If the reflection is gone, then it's pretty clear that the under side of the mirror assembly is the culprit.

[Richard Dickins]

Ross - those were my thoughts, but comparing the underside of the mirror on the 5D2 with the 5D, they look the same...

BUT...

On closer inspection there is a difference:

At the front of the mirror there is a small strip about 5mm wide, as shown in this picture with the mirror locked-up:



Both 5D and 5D2 have this strip.... BUT:

In the 5D2 this strip is shiny, and on the 5D, it is matt.

This shiny strip is what's doing it as you can see in the following images where I caught the angles just right:





This is where the reflection is coming from.

So, this shiny strip on the 5D2 looks like a design fault on the 5D2 compared to the matt strip on the 5D, which, no matter which way I look at it, does not project a reflection onto the sensor as shown above.

I think I am going to have to have a word with Canon in the UK about this to see if I can get the shiny strip replaced with a matt strip like the 5D.

Can anyone else with a 5D2 have a quick look to see if their strip is shiny or matt?