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Erwin Puts, Monochrom Part 2
- Thread starter monza
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Shashin
Well-known member
An interesting thing which I have been wondering about is the spectral response of the M9M. It really is different. It seems very sensitive to blue which is surprising.
This was an interesting statement:
This was an interesting statement:
Actually, the standards for determining ISO for a digital camera are published. And there is more than one method. But Puts should be able to figure it out.
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glenerrolrd
Workshop Member
A nice exhibit of the noise levels . Usable high ISO depends heavily on the requirements of the photograph ..some shots at ISO 10K look great but generally they do not require the rendering of the finest details . Finally a fair illustration that shows the mono has 2EV better noise levels . If you work with a M9 DNG and convert to B&W ..you can see noise at 640 and need to correct for it at ISO above that level . An M9 file dies above 1000 ..you lose tonal separation and rendering of the finest detail . The MONO looks to be exactly 2EV better at 2500 you still have a decent file but then it falls off the cliff .
The 2nd part to the performance is the spectral response (as Puts describes ) ....can you shoot without filters and get the tones you need ? If not do you really have a ISO advantage . Add a RED filter and lose the 2 EV advantage ?
No question in good light you can produce noticeably greater detail with or without filters ....but how is performance when shooting at night ? As EP states ..this will be up for debate .
The 2nd part to the performance is the spectral response (as Puts describes ) ....can you shoot without filters and get the tones you need ? If not do you really have a ISO advantage . Add a RED filter and lose the 2 EV advantage ?
No question in good light you can produce noticeably greater detail with or without filters ....but how is performance when shooting at night ? As EP states ..this will be up for debate .
Shashin
Well-known member
I shoot with monochrome sensors. Without filters, there is no control over spectral response--the file is simply luminance data of all frequencies. The MM does have a very different response to color than the human visual system, which definitely gives it its look. Whether you like the look will be up to you. This will also probably make the MM image unique from the M9 and other Bayer sensors. Which is "better" is going to be personal choice again. The MM images are rich, but I also the like the ability to mix channels during conversion.
IWC Doppel
New member
Looking at the M9 vs MM for B&W colour comparisons, it appears that the M9 has a greater level of differentiation of colours ?
Shashin
Well-known member
I would say the M9 is closer to the visual response than the MM. Color is our response to light--color does not really exist. A monochrome camera does not see color, it only sees luminance. Because its spectral response does not match our perception of color, the luminance distribution of the color patches look different--blue seems brighter in the MM, for example. It looks strange/different because it is probably more linear than human perception. I think this is what make processing MM images a bit of a challenge.
Hosermage
Active member
Let me preface this question to say that I don't know much...
I assume the BW film react similarly, meaning only see luminance? So in a way, shouldn't the MM result look much more like how a BW film will react? I also assume that different film will react differently because of chemistry. So is there a BW film that have unbiased response to color where it would mimic the MM exactly?
Edit: another question... if our eyes gives different color different weight, then there should exist an inverse weight/ratio to bring the result back into a unbiased state?
I assume the BW film react similarly, meaning only see luminance? So in a way, shouldn't the MM result look much more like how a BW film will react? I also assume that different film will react differently because of chemistry. So is there a BW film that have unbiased response to color where it would mimic the MM exactly?
Edit: another question... if our eyes gives different color different weight, then there should exist an inverse weight/ratio to bring the result back into a unbiased state?
jonoslack
Active member
Well, I'm not sure that it's so much of a challenge. I think it's very like dealing with black and white film: you get what you get (I don't mean that it looks like film). I rather like the output, and although I began by using filters I ended up accepting it for what it was and working with that.
What it definitely is is different - from anything else, even shooting is different because of the lack of highlight headroom. Challenging and interesting though.
all the best
Jono
chrism
Well-known member
A few days ago I realised something very odd. I have been thinking about the need for filters (yellow, orange, red, green) in all the sizes of my lenses. Then it hit me: I use film cameras with B&W film all the time and rarely wish I had used a filter. Why would I consider the MM any different? - only because the forums tell me I should! When the courier delivers my MM tomorrow I shall refrain from filter use until I deem it necessary. After all, my photos only need to satisfy me.
Chris
Chris
Shashin
Well-known member
Whether film and a CCD have the same response, I am unsure. Certainly film can have a different response--film is naturally responsive to blue light and need different chemicals to make it sensitive to green and red. My understanding is sensors have a broader response and they are certainly stronger in near IR. Although I went back to the link and it seems film and the MM are close.
Color is our response to wavelength. Part of it is physical, part psychological. If you think of a color space as a stack of plates with the dark plate at the bottom and the light plate at the top. And each plate has all the colors going from blue to red around the edge and as you approach the middle of the plate you lose saturation where gray is in the center, then you have a color space. Now an ideal color space would be a cylinder--a stack of plates. Every color could exist at every brightness and saturation. In actuality, the human color space is like a lopsided kidney--you cannot have (perceive) a very dark saturated yellow nor a very bright saturated blue.
If you look at the test target in the link. On the right panel on the second column you have the secondary and primary colors--cyan, yellow, and magenta, and red, green, and blue. In color, the blue is very deep. The MM sees that as brighter--at least it does with my eyes and monitor. But the camera is actually picking up more light from it. Your eyes get less sensitive at the blue and red ends of the spectrum and peak in the green. There is nothing I can see where the MM is being filtered in this way, so the response to color will be different from ours.
I really don't think of it as a problem, I just find this interesting (B&W s an abstraction and to say it is "correct" or "realistic" in any degree is a little absurd). Folks with MMs have said it took awhile to get used to processing. How much is that to the spectral response, I do not know. But it is fascinating. All my monochrome cameras are attached to microscopes and so I have not photographed more ordinary subjects--everything looks strange (or normal) under a scope.
I am not arguing about whether the MM is good or a M9 is better or any thing else of the kind. I am just interested in the technology and how it renders the world. I have seen great things from the MM and was interested in the comments made by those who use it. Most mention it took sometime to get used to. I was wondering if specrtal response had anything to do with it and perhaps it does not. But the camera does see a different world.
Shashin
Well-known member
Most of my B&W work was unfiltered. I did carry a red for skies, but as time went on, I used it less and less. I am sure the MM will be the same.
jonoslack
Active member
I quite agree - black and white is already an abstraction, and so 'correct' is a bit of a non-concept. Mind you, colour in mixed lighting on a sunny day might be argued along the same lines!
After years struggling with colour (and black and white), I do much less fiddling these days - I trust the camera, and if I don't like what it gives me, then it's the wrong camera!
Shashin
Well-known member
Well, there is some interpretation in color. But if you push it is far as you can in B&W, it just looks unnatural. B&W is certainly more plastic while retaining the illusion of reality.
Like many photographers of my generation, I started with B&W. There was always this idea of having to think in B&W, think in contrast--reds and greens can look identical when the color information is lost. And after some time you learned to anticipate the results. I always though it was simple. But then there was quite a bit of time between when the film was shot to when you saw a prints--at least measured in hours (saving and excepting Polaroids). So you only had the memory of the scene. With digital, we can get instant feedback.
Now, I wonder if the spectral response was part of that and the visualization was part of that. Sometime I knew the light would give a particular look beyond what I was seeing. Subtle stuff though that you would see in textures.
Now, I am doing much more color and have been for awhile. And when I look at some of my black and white and try to transpose them back into color, it is not that simple. Now, a B&W conversion from a color file is not really like B&W film; there is something different. Perhaps the B&W film look we have talked about is not really because it is film, but because of the color relationships and how that impacts the tonality. Interesting idea, but I am not sure how to test it until someone sends my their M9 and MM.
Like many photographers of my generation, I started with B&W. There was always this idea of having to think in B&W, think in contrast--reds and greens can look identical when the color information is lost. And after some time you learned to anticipate the results. I always though it was simple. But then there was quite a bit of time between when the film was shot to when you saw a prints--at least measured in hours (saving and excepting Polaroids). So you only had the memory of the scene. With digital, we can get instant feedback.
Now, I wonder if the spectral response was part of that and the visualization was part of that. Sometime I knew the light would give a particular look beyond what I was seeing. Subtle stuff though that you would see in textures.
Now, I am doing much more color and have been for awhile. And when I look at some of my black and white and try to transpose them back into color, it is not that simple. Now, a B&W conversion from a color file is not really like B&W film; there is something different. Perhaps the B&W film look we have talked about is not really because it is film, but because of the color relationships and how that impacts the tonality. Interesting idea, but I am not sure how to test it until someone sends my their M9 and MM.