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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 :)

Weird Red Dots? Anybody know what this is?

If you take off your lens and look at your sensor - you can see the dot pattern on the OLPF… very simple to understand what is going on here.
 
What’s interesting is that RED put the OLPF and IR filter it seems substantially in front of the sensor itself. Some MF cameras and backs have the IR and OLPF much closer to the sensor and in some cases they are removable. For aerial work you can actually put the “green” IR filter on the front of the lens.

So when stopped down and shooting into the sun it seems you are getting predominately collimated principal rays. This is why the diffraction/interference/reflection artifact is so clear.

But I think we forget how sensitive the Scarlet/Epic sensor really is, and perhaps we should “treat it” with a bit more respect.

So something you could try would be to get a very good ND filter that is also a precision piece of glass. If you build a deep mini matte box and have the ND filer angled between 30 and 45 degrees inside said matte box and open up the aperture a bit then this should eliminate a lot of what you are experiencing.

If you have to shoot into the sun then clearly you are not going to get away with it without something in front of the lens. To me this is a normal or reasonable expectation/precaution to take.

Not that I get to see that shiny ball of light in the sky as often as I would like…

Cheers,

Eric
 
When I originally posted I didn't mean any disrespect, I was just trying to learn what was going on, it surprised me cuz I'm new to Red. I tried opening up the iris and adding nd, the solution works fine for my purposes. Thanks for the input though
 
What kind of 18mm Zeiss? A modern well-made digital lens should have a multicoated rear element to reduce this sort of reflection, whereas older film lenses (and cheaply made ones) are uncoated or single-coated, so they'll be worse for reflections like this.
 
Stephen Strangways said:
What kind of 18mm Zeiss? A modern well-made digital lens should have a multicoated rear element to reduce this sort of reflection, whereas older film lenses (and cheaply made ones) are uncoated or single-coated, so they'll be worse for reflections like this.
Click to expand...

Zeiss ZE Distagon f 3,5 Canon Mount
 
Ryan Emanuel said:
When I originally posted I didn't mean any disrespect, I was just trying to learn what was going on, it surprised me cuz I'm new to Red. I tried opening up the iris and adding nd, the solution works fine for my purposes. Thanks for the input though
Click to expand...


No “disrespect” read as such… When I say treat it with more respect I meant “physically” and “technically” as it is in essence a sensitive instrument.

I.e. if you are going to point a very sensitive high bandwidth photonic device directly at the sun you can expect things to go a little wonky/or pear shaped without modulating or filtering such an “input”.

Purely technical, not personal or being overly "sensitive" about a RED device or product…

No worries.

Eric
 
David Battistella said:
The OLPF is RED. that is why the reflection is RED. It's a kind of RED mirror. Has been this way since the first camera.

David
Click to expand...

Off topic but just wondering, anyone has any idea why RED's olpf is red as opposed to most other digital cameras which is green?
 
These threads that are started about stuff that could be easily found by doing a search are getting pretty entertaining to read.... :lurk5:
 
Brian Iannone said:
I like your little smiley. It's true that this is just like watching a show and eating popcorn!
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Omnomnomnomnomnomnom
wine-drinking-emoticon.gif
 
Talking with real people is much more rewarding and satisfying than "doing a search". Imagine everyone just used google instead of forums!? I hate this mentality!
 
Matthew Scott said:
Talking with real people is much more rewarding and satisfying than "doing a search". Imagine everyone just used google instead of forums!? I hate this mentality!
Click to expand...

Matthew,
I'm referring to forum search. A lot of this information is easily found on the forum and has already been discussed. Not trying to be rude man, and I completely agree with you, it's much better talking to real people instead of googling... but it also sucks to have to dig through 10 threads about the same thing to find what you're looking for...
 
Trevor Meeks said:
Matthew,
I'm referring to forum search. A lot of this information is easily found on the forum and has already been discussed. Not trying to be rude man, and I completely agree with you, it's much better talking to real people instead of googling... but it also sucks to have to dig through 10 threads about the same thing to find what you're looking for...
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+1

Oh, I thought Matthew was just being sarcastic.


Trevor Meeks said:
less than 48 hours.

YMMV
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Wow, okay.
 
so do I, too bad I didn't know what to search for sincee I had no idea what was causing the problem.
 
OLPF
 
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