Source light artifacts???

[Ido Karilla]

While shooting tests with the MX + Zeiss high speed lenses with and without IR filter we encountered a phenomena that bothers us.

Our only explanation is that the sensor is reflected on the lens.

Please look at the attached images and come up with a simple solution, we are about to start shooting in two days.

Thank you.

 

[Ido Karilla]

???

???

Did I post it in the wrong place?

No one ever encountered this? No solution?


Thanks.

 

[David Mullen ASC]

It's a combination of lens narcissus and a reflection off of the sensor, or actually, the IR/OLPF in front of the sensor. Using an extremely low-flare lens might help (such as a Master Prime) but there isn't much you can do about the sensor reflection.

You can see the same effect here in Sanjin's test, just not as strong:
http://reduser.net/forum/showthread.php?t=46489

 

[Luca Immesi]

We had the same issue with M camera with Zeiss Ultra prime and also RPP.
The good thing is it happened two or three times in 2 years in particular light conditions.

 

[ericyoung]

Also this previous thread:

http://reduser.net/forum/showthread.php?p=554665&highlight=reflection#post554665

Not a massive issue for me except I wish the OLPF was neutral rather than red in colour, as such reflections are unavoidable in some situations. anyone know if the new M-X/EPIC/Scarlet sensors/OLPF still look red?

 

[jbeale]

I assume the problem would be much less visible if you could reduce the lighting ratio between the direct candle flame, and the subjects' faces. Maybe some kind of gradient or localized-spot ND filter that selectively dims just the direct view of the flame? (Assuming it's a static shot)

 

[David Battistella]

Were you using a screw in UV on the front of the lens?

 

[Mike Gross]

You're seeing the effects of super high isos which lens coatings arent usually designed for.

 

[Mark Andersen]

I've seen the red fog too, it happens in certain situations now and then. Last time was a sunset shot with sun in frame just behind actors. It didn't really adversely effect the shot, but it was there.

Mark

 

[Ido Karilla]

Thanks.

Thanks.

Thank you all for your very helpful replies.

 

[Nook Kim]

You're seeing the effects of super high isos which lens coatings arent usually designed for.

Hi Mitch,

Could you elaborate on this? I don't quite understand your statement. Thanks in advance!

 

[Cail Young]

Not a massive issue for me except I wish the OLPF was neutral rather than red in colour, as such reflections are unavoidable in some situations. anyone know if the new M-X/EPIC/Scarlet sensors/OLPF still look red?

The filter package in front of the sensor cannot simultaneously cut IR pollution efficiently and reflect all wavelengths of light equally off the front surface. It's a catch 22.

To the OP:
This is definitely reflection of the sensor filter package off the back of the lens. It happens when you have a strong light source straight down the barrel. I have seen it on many many lenses but have not tried a Master Prime yet...

 

[JD Holloway]

Were you using a screw in UV on the front of the lens?

I've been caught a couple of times with that one, scratched my head, and went, "AH-HA!"