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02-19-2016, 05:35 PM   #16
PDL
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Back in the dark ages (literally) I wore Photogray glasses, when I was just starting to get serious about photography. The problem was that when you went outside into natural light they would darken whether you needed them to or not. It was a real problem when I was skiing, because on cloudy days they would get just as dark as on sunny days. I would assume that the technology has improved over the decades, but just check out what wavelengths switch on the effect. I discovered it was UV light which at high elevations (where I lived and skied 7,280ft -> 2,218m to 10,000ft -> 3,048m) was very high even on cloudy days. The use of Photogray glasses totally screwed with my mind when deciding what to shoot.

The Elitist - formerly known as PDL


Last edited by PDL; 02-19-2016 at 05:37 PM. Reason: Clarity
02-19-2016, 05:38 PM   #17
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QuoteOriginally posted by PDL Quote
Back in the dark ages (literally) I wore Photogray glasses, when I was just starting to get serious about photography. The problem was that when you went outside into natural light they would darken whether you needed them to or not. I was a real problem when I was skiing, because on cloudy days they would get just as dark as on sunny days. I would assume that the technology has improved over the decades, but just check out what wavelengths switch on the effect. I discovered it was UV light which at high elevations (where I lived and skied 7,280ft -> 2,218m to 10,000ft -> 3,048m) was very high even on cloudy days. The use of Photogray glasses totally screwed with my mind when deciding what to shoot.

The Elitist - formerly known as PDL

I have the same issue because I wear photochromic lenses. Quite difficult to judge the exposure just be chimping on the LCD. As per my previous comment, newer Transitions lenses now react to visible spectrum. Technology improves every day.
02-19-2016, 05:39 PM   #18
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QuoteOriginally posted by dtmateojr Quote
No sensor as of present is capable of capturing the entire visible spectrum.
Rubbish.This is a QE response curve from a monochrome sensor, which is a sensor without a bayer filter to separate RGB components:


This sensor goes beyond what is perceptible to humans.

QuoteOriginally posted by dtmateojr Quote
Cameras meter with the lens wide open. So the filter will react at f/1.8.
Correct, however what happens if someone is using a slower zoom lens of f/5.6? or when you use a polariser?

QuoteOriginally posted by dtmateojr Quote
If it takes a minute to darken that's fine. Since lenses concentrate light on the focal plane it should not take longer than that.
The filter, if it was at the sensor plane would only have a fraction of a second to adjust unless you leave the shutter open to allow it to adjust.

Last edited by Digitalis; 02-19-2016 at 05:46 PM.
02-19-2016, 05:41 PM   #19
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yes but your bayer filter array will screw with that behaviour

---------- Post added 02-20-16 at 10:42 ----------

and please make sure you quote me in context. i look stupid in your last comment.

---------- Post added 02-20-16 at 10:50 ----------

QuoteOriginally posted by Digitalis Quote
Rubbish.This is a QE response curve from a monochrome sensor, which is a sensor without a bayer filter to separate RGB components:


This sensor goes beyond what is perceptible to humans.



Correct, however what happens if someone is using a slower zoom lens of f/5.6? or when you use a polariser?



The filter, if it was at the sensor plane would only have a fraction of a second to adjust unless you leave the shutter open to allow it to adjust.

If somebody uses a slower lens then they will have to wait longer. Same with polariser. Those that use big stoppers wait longer during exposure. There are limitations but if DR is the problem it's a very reasonable compromise.

The filter will have to be very close to the sensor but in front of the shutter curtain and will need to be corrected for refraction.

02-19-2016, 05:57 PM   #20
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QuoteOriginally posted by dtmateojr Quote
The filter will have to be very close to the sensor but in front of the shutter curtain and will need to be corrected for refraction.
The filter would have to be ON the sensor for the edges to line up - you would get contrast halos if it was further out.

QuoteOriginally posted by dtmateojr Quote
please make sure you quote me in context. i look stupid in your last comment.
well you wrote something stupid, Bayer equipped sensors are quite capable of capturing the visible spectrum. the Bayer filter merely separates the visible spectral components:



The Red/Blue pixels are interpolated simply because there are fewer of them, which reduces the resolution for those channels relative to the green channel* on a bayer type sensor.

*the green channel accounts for 50% of the pixels on a bayer sensor.

Last edited by Digitalis; 02-19-2016 at 06:03 PM.
02-19-2016, 06:03 PM   #21
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QuoteOriginally posted by Digitalis Quote
The filter would have to be ON the sensor for the edges to line up - you would get contrast halos if it was further out.



well you wrote something stupid, Bayer equipped sensors are quite capable of capturing the visible spectrum. the Bayer filter merely separates the visible spectral components:

Why would it need to be on the sensor? Have you not heard of lens extenders?

The bayer filter only lets RGB colours hit the sensor. I don't understand your argument. I really don't. Why do you keep insistng on capturing the entire spectrum?
02-19-2016, 06:10 PM   #22
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QuoteOriginally posted by dtmateojr Quote
Why would it need to be on the sensor? Have you not heard of lens extenders?
why would you want a lens extender in front of your sensor?

The filter would have to be on the sensor so that the contrast edges would match up properly - if they don't you would get contrast halos.


Last edited by Digitalis; 02-19-2016 at 06:16 PM.
02-19-2016, 06:14 PM   #23
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QuoteOriginally posted by Digitalis Quote
why would you want a lens extender in front of your sensor?

Telephoto extenders? Those additional lenses that a lot of mirrorless cameras use for legacy lenses? Those lenses are VERY VERY FAR from the sensor. If a complex lens can be corrected why not a very thn filter? Duh?!!!
02-19-2016, 06:27 PM   #24
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QuoteOriginally posted by dtmateojr Quote
Telephoto extenders? Those additional lenses that a lot of mirrorless cameras use for legacy lenses?
Teleconverters reduce image quality, sometimes catastrophically when wide angle lenses are involved. Landscape photography frequently involves wringing every last bit of image quality out of the entire imaging system. No landscape photographer in their right mind would ever use a TC even IF it did give them 20 stops of DR.

QuoteOriginally posted by dtmateojr Quote
Duh?!!!
This kind of language doesn't enhance my impression of your intellect or the validity of your argument. Conceptually, I understand what you are talking about, but your approach is fundamentally flawed due to a lack of understanding of the materials involved, Imaging sensor capabilities and the laws governing optics.
02-19-2016, 06:32 PM   #25
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A crazy idea

QuoteOriginally posted by Digitalis Quote
Teleconverters reduce image quality, sometimes catastrophically when wide angle lenses are involved. Landscape photography frequently involves wringing every last bit of image quality out of the entire imaging system. No landscape photographer in their right mind would ever use a TC even IF it did give them 20 stops of DR.



This kind of language doesn't enhance my impression of your intellect or the validity of your argument. Conceptually, I understand what you are talking about, but your approach is fundamentally flawed due to a lack of understanding of the materials involved and the laws governing optics.

Landscape photographers layer multiple filters in front of their lenses. It's not something new. We do it all the time. Don't tell me that speed boosters are useless either. And Sony must be really stupid for using translucent mirrors in their cameras.

The "duh" is for making me look stupid and saying that my comments are stupid. There is a difference between crazy and stupid. Stupid is when you have no idea what you are talking about like insisting on capturing the entire visible spectrum and thinking that anything you put behind a lens is stupid. That is stupid.

Last edited by dtmateojr; 02-19-2016 at 06:43 PM.
02-19-2016, 06:44 PM   #26
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QuoteOriginally posted by dtmateojr Quote
Landscape photographers layer multiple filters in front of their lenses. It's not something new.
And because those filters are on the front of the lens they will be out of focus, what you are suggesting requires a high degree of edge alignment between areas of high and low contrast - which means you would have to place the filter very close, if not directly on the sensor. If you place the filter further away form the sensor the filter itself will be rendered out of focus which will cause contrast halos, the result of which would look like a poorly blended HDR:

The image would look like this:


( not my work, thank god)


QuoteOriginally posted by dtmateojr Quote
Don't tell me that speed boosters are useless either.
Any additional piece of glass you put between a lens and a camera is going to alter the characteristics of the lens itself, in a majority of cases the effects are reduced resolution and contrast. In the worst cases increased astigmatism, chromatic aberration, increased amounts of LoCa, coma, vulnerability to flare and amplified field curvature.

QuoteOriginally posted by dtmateojr Quote
Stupid is when you have no idea what you are talking about like insisting on capturing the entire visible spectrum.
I take it you have issues with colour photography?

QuoteOriginally posted by dtmateojr Quote
and thinking that anything you put behind a lens is stupid.
Cameras go behind lenses. Exactly when did I say cameras are stupid?

Last edited by Digitalis; 02-19-2016 at 06:59 PM.
02-19-2016, 06:58 PM   #27
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QuoteOriginally posted by Digitalis Quote
And because those filters are on the front of the lens they will be out of focus, what you are suggesting requires a high degree of edge alignment between areas of high and low contrast - which means you would have to place the filter very close, if not directly on the sensor. If you place the further away form the sensor the filter will be rendered out of focus which will cause contrast halos, the result of which would look like a poorly blended HDR:

The image would look like this:


( not my work, thank god)




Any additional piece of glass you put between a lens and a camera is going to alter the characteristics of the lens itself, in a majority of cases the effects are reduced resolution and contrast.



I take it you have issues with colour photography?


Cameras go behind lenses. Exactly when did I say cameras are stupid?


News flash: SONY uses translucent mirrors. OMG! They must be stupid.
02-19-2016, 10:11 PM   #28
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@dtmateojr, the concept you proposed *must* be applied just before the sensor, similarly to the Bayer array filter.
02-19-2016, 10:14 PM   #29
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QuoteOriginally posted by dtmateojr Quote
... areas of the frame that are bright are automatically darkened proportional to the intensity of light...
I thought modern sensors already behaved like that?
02-20-2016, 12:29 AM   #30
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QuoteOriginally posted by DeadJohn Quote
@dtmateojr, the concept you proposed *must* be applied just before the sensor, similarly to the Bayer array filter.

Yes. The closer to the sensor the better. It must not get in the way of lenses.

---------- Post added 02-20-16 at 17:30 ----------

QuoteOriginally posted by akptc Quote
I thought modern sensors already behaved like that?

They don't. They are actually really bad at handling highlights. They clip very easily.
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