Red circles

[M. Bergeron]

We just received our Epic and we are in admiration with this little beast.

So far everything went fine except for this:

I remember Tom Lowe writing about this somewhere but I don't remember if there was a workaround or a way to avoid it while keeping the sun in the frame.

It seems to be visible only with wide angle lenses.

Thanks for helping.

 

[Justin Kirchhoff]

I believe that has something to do with the lens elements bouncing the sun light around inside the lens. I've only had this problem once shooting into the sun, although it was with a Nikon 70-200 zoom, not a wide angle...

 

[John Marchant]

MX sensor has always done this on R1, and same now on EPIC. Seen it with a wide variety of lenses when shooting straight into the sun, one of a very small list of things I wish were different. Don't recall seeing it with the M sensor, but maybe it just never arose for me.

 

[Loic Parent]

...Don't recall seeing it with the M sensor, but maybe it just never arose for me.

Just for info i had thoses dots too but with the M sensor, 18mm and sun in the frame. must be the light bouncing in the lens?

 

[Jeff Kilgroe]

This is "OLPF" flare as it's often called. It's an internal reflection from the OLPF/ Sensor Block. Easy to reproduce on most CMOS and digital systems with reflective sensor structures. RED One shows it (both MX and on the original M sensor), so does Alexa and others. The Alexa's low-con filter overlaying the sensor block/ OLPF seems to soften it somewhat, probably because it becomes the outward reflective surface more so than the OLPF or sensor. Just one more layer of glass...

I'm not trying to drag the Alexa into a beat-down with this one, just mentioned it. It's easy to duplicate this sort of reflection or flare with *ANY* reflective sensor camera. If you look into a camera and see a shiny sensor surface reflecting back at you, then you know it's possible for light to bounce back and forth inside there.

 

[David Battistella]

What lens is this?

I've seen this a lot
It's the light is hitting the reflective surface of the OLPF, then bouncing back off the rear of the lens, then back onto the OLPF, etc.

In low sunsets you will often see two suns, the sun and the reflected sun appearing as a dot.

In this shot, because of the angle it looks like flare, but you can clearly see the blades of the iris and the (not so round BOKEH).

It's like standing between two mirrors both the OLPF and the back of the lens are reflective surface.

Does this make sense?


David

 

[M. Bergeron]

Thanks a lot for the feedback. The lens was the original 18-50. This is not a final shot, just some tests walking around town.
I remember getting some kind of internal reflection with the M sensor but it was never that apparent. I shoot a lot of things with the sun in the frame and I never had to consider it an issue. Yesterday's test shoot is full of it in every wide shot where the sun shows up. Tomorrow I will try with the RPP since I rarely use the 18-50 for that kind of shot. Probably, they will handle this in a better way hence why I never experience this before yesterday.

What happens when you completely remove the OLPF?

 

[Erich Ocean]

What happens when you completely remove the OLPF?

Aliasing, and also the sensor is left unprotected, so it's likely to get scratched or dust on it, which then gets scratched when you got to clean it off. Leave the OLPF on. ;-)

 

[Mark Pedersen]

I had the exact same pattern shooting a RED ONE into the sun early in the AM. I thought it was internal reflections on the MB filters.

Good to know. Thanks.

And yes they were distinctly pink when there was no other pink in the shot other than the lens flares. So it makes sense that they would be caused by the OLPF.

M

 

[Mark Toia]

Is this a EPIC ssue... I've seen this on almost every camera I've used for the last 20 years..... all sorts of colors as well.

 

[Eric Ulbrich]

here is an interesting article on this phenomena with ALL digital cameras.
http://thesybersite.com/minolta/sensor-reflection/

 

[Mark Toia]

We just received our Epic and we are in admiration with this little beast.
So far everything went fine except for this
It seems to be visible only with wide angle lenses.

Thanks for helping.

Veeeeery interesting.... I just dragged up the RED Channel in your picture
I stand corrected, I've never seen this on every camera Ive used in 20 years. Obviously a crazy phenomena with ALL digital chip cameras.

 

[Tim Whitcomb]

I personally think it looks cool, although I presume it does not fit your narrative?

Perhaps we should all challenge ourselves to find a story that fits this beautiful image