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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Epic STREAK FLARING

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Adam Eden said:
I stuck thin camera tape all around the metal in front of the sensor and it didn't make a difference.
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The problem area is the rubberish part with surfaces about 8mm deep, perpendicular to the sensor (like a reflective window sill that runs around the OLPF. Top, bottom, and sides).

Here's before and after pics - tape applied to the area just in front of the OLPF to cut the flare

No mattebox or flagging was used on either shot.
THe lightsource just out of shot is a twin-LED flashlight - hence the two flares.
The out of focus blob is the stand the flashlight was sitting on.
The reduction of flaring at the very top of the frame is due to shadowing caused by a tiny vertical surface near the OLPF, that "flags" the reflective surface.


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You can see that the flashlight caused virtually no actual lens flare. The flare is basically 100% due to bounce off the OLPF mount. Only the vaguest, soft blue tint remains.
 
Mark P, I have a shoot today with my Epic and on my steadicam. I will tape the hell out of everything internal and try again, but I would like to see a pic of what you are talking about.

I have a 4k backlight/ liner in shot so it will definately show up without it.
 
There's a problem area behind the OLPF glass also, that will reflect objects slightly more out of frame.
That reflective area can't be accessed by the camera user.
 
A light in shot won't flare. It's got to be outside of frame at just the right angle to bounce off the "sill".

you can see how light bounces back from the OPLF, onto the the side area of the rubbery part, on the right of the sensor (north-east of the yellow tape).

Here's a pic without the yellow tape. You can see the back-reflection, and how shiny the part is, under the OLPF, and to the side also.

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Thats exactly what I taped up also. And I can see in your case it has made a difference.

But what I can see that still is a problem is the thickness of the shiny metal as the metal edge facing the sensor is probably causing the flares and you can't tape that part up. On the RED ONE it is made from a solid piece of plastic.

It is good we are all talking about this and something hopefully will be addressed by RED.

Good work Mark P!
 
I would humbly suggest that the differences between adam and marks results may have to do with the fact that not all black paper tape is created equal. Some are glossier than others.

Nick
 
Huge fix Mark. That streak on the fish was other-worldly. Very irritating to say the least. At least to me.

Thanks for letting everyone know how to handle this.

Stephen
 
Threads like this is why RedUser, despite the noise, is awesome. Thanks guys for investigating this, and coming up with workarounds/fixes.
 
Erich Ocean said:
Threads like this is why RedUser, despite the noise, is awesome. Thanks guys for investigating this, and coming up with workarounds/fixes.
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All part of the service. I'll be sending Deanan an invoice for the diagnostics, after someone else can reproduce my fix. Kidding. Kidding.
 
Paul Leeming said:
This is pure speculation, but given that more of the Mysterium-X sensor is used in Epic compared to the Red One (and possibly exposed to light), it may well be that Super35 lenses with a tight circle (ie. little additional coverage above their rated coverage) are getting edge flaring on the limit of their optics.

Also bear in mind that with more of the sensor exposed to light, things that aren't visible on the viewfinder due to sensor cropped ratios may still be flaring below or above what you can visibly see.
Click to expand...

It looks like Mark Pugh may have found the main issue but Paul brings up a very good point. It isn't talked about much but the Epic sensor is quite a bit larger than S35 and the sensor "sees" more of a lens than other cameras do. People pointed out that the flare in Mark Toia's 3rd still looks different than the ones from the RED One. Check out what happens if you crop the image to the RED One sensor size though: the flair looks identical to the 2nd still from the RED One.

flare-comparison-800px.jpg


flares-r1.jpg
 
The look of the flair is identical though. I wasn't there so I can't say for sure but it looks like there is a bright reflection off the water under his right elbow that is causing the flair.

My point was flairs will look slightly different on Epic because of the larger sensor.
 
Julio Quintana said:
Justin, it is not identical at all because, as noted earlier, there is no light source in the Epic image, whereas the RED MX image has the sun just out of frame.
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The reflection off the water.

Also, remember that to flare the source only has to ping the lens element in a way that travels down the optical path to the sensor ... something easier when you see more of the image.

I still think that this is a big part of the perceived problem, and that using the mattebox more effectively is the solution.

Quite a bit of what I've seen here is just lenses flaring perhaps from a wider FoV than people are used to. Be aggressive with the flags .... get them set just outside the FoV of the current lens.

The internal reflection thing Mark figured out is only part of the reported problem.
 
This is all quite interesting. I admit, my original post way back in this thread was only based on viewing the OP's circus clip. I haven't run across this flaring issue myself, been out of town on other business, but will do some tests this weekend. If it is the shiny surface, then this is essentially a type of "gate flare" and we will probably see it on lenses which allow for light to emit at incidence angles beyond the coverage circle or beyond the sensor area, which could then encounter that shiny surface and bounce back toward the sensor -- causing a streak or a flare. Er, hypothetically, of course. I'm still not convinced though, the flares still appear to be typical and completely controllable with proper light shielding -- mattebox, flags. The EPIC's usable sensor area is larger. So I agree with Paul and Justin, that the flares Mark posted could very well be the same flare, just looking different to some extent with the different sensor coverage. The flares themselves have the same properties as they approach the center of the image and none of Toia's examples look like an internal reflection to me, due to the refraction and rays/tendrils.

I'll see what I can replicate....
 
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Today's Epic firmware update and Mark's taping fix would be the menu of things to do this Saturday.
 
Alexander Ibrahim said:
The internal reflection thing Mark figured out is only part of the reported problem.
Click to expand...

Well, in my test, getting rid of the reflective surface in front of the OLPF solved the problem.
Taped-up surface, no flare. No mattebox flaps or superior flagging technique needed.
Which is handy if you're, say, hanging out of a helicopter with a camera, at high speed.

Do your own test.
 
Hey Mark (Pugh) ...

Your dead on... !

Just looked inside the EPIC and can see exactly what your talking about. That shinny 45 degee angled surface.. light hits that and bangs straigh up the side of the chip.
well looks like it does.
On the 435 we had a shinny metal square ring around the gate and this would do exactly the same reflective flare...

So this is purely light bounce or reflective bounce internal washing up the side of the chip.. Not a chip issue as I can see. Paint it all MATT black in there like all the still cameras you purchase and Im sure the problem will disappear.

I'm sure RED are onto to it. :)
High lighting this little flaw Adam is good. I'm sure RED appreciate it a lot. Unfortunately a little fix or a recall may have to happen... but hey RED are famous for doing that anyway if they are not happy with it themselves.
Thats what makes that company so great.

I will miss the little flare however... Sometimes you have to pay thousands to put them into the image.. :)))))))))
 
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