Comparing Olympus 4/3lenses to FX "Full Frame" offerings

Started Jan 25, 2014 | Discussions
bobn2
bobn2 Forum Pro • Posts: 63,469
Re: Tiger1, I need your help!
3

Tiger1 wrote:

Jay Ell wrote:

Tiger1 wrote:

Hi, I am a bit puzzled, and as a knowledgeable person I am sure you can help me out:

Assumptions:

Let's assume that the pixels of both test systems are the same as the other technology as well. Let's also define that I use ISO 100 and 1/1000s shutter speed for each shot. Also the sensors have the same aspect ratio (4:3).

The questions:

I'll take a picture with 150mm f/2 lens on a 4/3 system, and I choose the f/2.8 aperture. Let's call this P-43.

Then I'll take a FF camera and put on a 150mm lens with f/2.8 aperture and take a picture and crop the picture to the 4/3 frame size - let's call this P-FF43.

Are the output pictures similar or different and if so, in which way? I think they should be identical in this thought experiment, but if not, can you help me out why not?

Of course they are the same! I never said they wouldn't be!

Then I'll take a FF camera and put on a 300mm lens with f/2.8 aperture and take a picture and do no cropping at all. Let's call this P-FF.

If I look at the picture out of this combinatiion at the size of typical piece of paper (A4 or letter size) and compare it to the P-43 and P-FF43, is the picture the same or different to those and if different, in what way? As you teach, the light density should be the same in all these images, and I think I just understand it, but shouldn't the P-FF get more light as it image the lens draws is bigger and it's captured by the bigger sensor area and if so, should the image be less noisy? Or does it matter at all? I am confused, please help me out.

The image on the P-FF will be of superior quality obviously. There are more pixels receiving exactly the same light density each so overall there will be less noise in the image as this noise will be "Zoomed Out" so to speak and made less obvious. The noise per pixel will be the same though.

Now that I think of this problem, what about Pentax Q? If I use a 55mm f/2.8 lens on it (P-Q), and output the picture is it just as good as the other cameras would make?

Please help me!

Don't know much about the Pentax Q sensor, its size, pixel count and I definitely don't know how it compares to the imaginary sensor you described above so I cannot answer that question with any surety. Sorry.

OK, three images all taken with the same lens, a Sigma 100-300/4 set at 300/4, same shutter speed. One is taken on a Pentax Q. The other two are taken on a E-1 and D800 and cropped to the same coverage as the Pentax Q shot. Which is which?

-- hide signature --

Bob

Tiger1 Contributing Member • Posts: 552
Re: As a photographer ..
2

Sergey_Green wrote:

Tiger1 wrote:

Now why do you think that anyone would care about the aperture diameter? The aperture diameter is only relevant when it is coupled to the focal length because as a photographer I actually measure light intensity (or luminosity) when I use a light meter. It actually gives me an F stop and a shutter speed. It does not give me an aperture diameter and then asks me for a focal length or vice versa. So f/2 IS f/2 when it comes to taking photos! Isn't that what this whole website is about? It is not about people like you getting so pedantic as to confuse everybody about what really is important.

The aperture diameter only explains why, but of course no-one should care what the exact size is. However, as a photographer, were you to shoot with different formats, would you care what your pics would look like at the end. After all, f/2 from FT and f/2 from FF are hardly the same. Would that matter?

F/2 is F/2 no matter what the format when it comes to exposure - that is what I'm talking about.

As a photographer I am interested in getting the correct exposure.

ISO, shutter speed and F stop determine exposure.

When it comes to DOF that is another matter.  The effect of F stop on DOF will depend on the focal length of the lens.  Because different formats have different angles of view, one has to change focal lengths to get the same perspective for each format.

Changing the focal length at a given aperture will then affect DOF.  To get equal DOF one has to increase ones aperture as the format gets smaller to retain the same perspective.

The F stop will still determine the exposure with the shutter speed for a given ISO.

So when it comes to EXPOSURE f/2=f/2=f/2 no matter what the format.

 Tiger1's gear list:Tiger1's gear list
Sony RX1 Canon EOS 5D Mark II Fujifilm FinePix S5 Pro Sigma SD14 Sigma SD1 Merrill +14 more
Great Bustard Forum Pro • Posts: 43,680
Re: As a photographer ..
1

Tiger1 wrote:

Sergey_Green wrote:

Tiger1 wrote:

Now why do you think that anyone would care about the aperture diameter? The aperture diameter is only relevant when it is coupled to the focal length because as a photographer I actually measure light intensity (or luminosity) when I use a light meter. It actually gives me an F stop and a shutter speed. It does not give me an aperture diameter and then asks me for a focal length or vice versa. So f/2 IS f/2 when it comes to taking photos! Isn't that what this whole website is about? It is not about people like you getting so pedantic as to confuse everybody about what really is important.

The aperture diameter only explains why, but of course no-one should care what the exact size is. However, as a photographer, were you to shoot with different formats, would you care what your pics would look like at the end. After all, f/2 from FT and f/2 from FF are hardly the same. Would that matter?

F/2 is F/2 no matter what the format when it comes to exposure - that is what I'm talking about.

No one denies that.

As a photographer I am interested in getting the correct exposure.

Please define "correct exposure". For example, if the "correct exposure" for a scene is f/4 1/200 ISO 400 on an E5, what is the "correct exposure" for the same scene with a FF DSLR?

ISO, shutter speed and F stop determine exposure.

Actually, the exposure is determined by the:

  • the scene luminance
  • the f-ratio (more properly the t-stop)
  • the shutter speed

The ISO setting does not change the exposure except inasmuch as it indirectly changes the f-ratio, shutter speed, and/or flash power, depending on the AE (auto exposure) mode you're in.

When it comes to DOF that is another matter. The effect of F stop on DOF will depend on the focal length of the lens. Because different formats have different angles of view, one has to change focal lengths to get the same perspective for each format.

The same goes with the total amount of light projected on the sensor for a given shutter speed, and thus the noise.

Changing the focal length at a given aperture will then affect DOF. To get equal DOF one has to increase ones aperture as the format gets smaller to retain the same perspective.

The F stop will still determine the exposure with the shutter speed for a given ISO.

So when it comes to EXPOSURE f/2=f/2=f/2 no matter what the format.

No one denies that f/2 = f/2 = f/2 when it comes to exposure. The point you're missing is that it's not the exposure that matters, but the total amount of light falling on the sensor. The competent photographer will seek to maximize the exposure (and thus also maximize the total light falling on the sensor) for the format they are using within the constraints of DOF / sharpness, motion blur / camera shake, and noise / blown highlights.

P.S.:  When you have a moment, Bob had a question for you downthread.  Be sure to click on the photos to see fullsize -- it may help in answering the question.

Art_P
Art_P Veteran Member • Posts: 9,936
you wouldn't want

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

-- hide signature --

Art P
"I am a creature of contrast,
of light and shadow.
I live where the two play together,
I thrive on the conflict"

 Art_P's gear list:Art_P's gear list
Olympus OM-D E-M5 Olympus E-M1 II Olympus M.Zuiko Digital ED 9-18mm F4.0-5.6 Panasonic Lumix G 14mm F2.5 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS +6 more
windsprite
windsprite Senior Member • Posts: 2,730
Re: you wouldn't want

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

 windsprite's gear list:windsprite's gear list
Fujifilm FinePix F100fd Fujifilm FinePix F550 EXR Panasonic Lumix DMC-FZ200 Nikon D2H Nikon D300 +47 more
Art_P
Art_P Veteran Member • Posts: 9,936
Exactly
2

but I hardly ever display at 8', so why waste all that ink?

Besides, a balloon blown up to 2' will last longer than one blown up to 8'  And those old shriveled balloons look so sad

-- hide signature --

Art P
"I am a creature of contrast,
of light and shadow.
I live where the two play together,
I thrive on the conflict"

 Art_P's gear list:Art_P's gear list
Olympus OM-D E-M5 Olympus E-M1 II Olympus M.Zuiko Digital ED 9-18mm F4.0-5.6 Panasonic Lumix G 14mm F2.5 ASPH Panasonic Lumix G Vario 100-300mm F4-5.6 OIS +6 more
Tiger1 Contributing Member • Posts: 552
Re: you wouldn't want
2

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!
Sensor size has little to do with enlargement.
The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

 Tiger1's gear list:Tiger1's gear list
Sony RX1 Canon EOS 5D Mark II Fujifilm FinePix S5 Pro Sigma SD14 Sigma SD1 Merrill +14 more
Great Bustard Forum Pro • Posts: 43,680
Bzzt.

Tiger1 wrote:

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Sure.

Sensor size has little to do with enlargement.

It has *everything* to do with enlargement!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

Wow, just wow.  It has everything to do with sensor size.  Well, more accurately, it has everything to do with aperture diameter and saturation capacity.

By the way, were you ever going to get around to answering Bob's question?  If not, is there any particular reason you don't want to answer?

Tiger1 Contributing Member • Posts: 552
Re: Bzzt.
1

Tiger1 wrote:

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Sure.

Sensor size has little to do with enlargement.

It has *everything* to do with enlargement!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

Wow, just wow.  It has everything to do with sensor size.  Well, more accurately, it has everything to do with aperture diameter and saturation capacity.

By the way, were you ever going to get around to answering Bob's question?  If not, is there any particular reason you don't want to answer?

I'm on my phone which limits what I can see image wise.
I have a social function after work so I won't get to my computer for another 24hrs.
That's why I can't answer Uncle Bob's question....yet.

 Tiger1's gear list:Tiger1's gear list
Sony RX1 Canon EOS 5D Mark II Fujifilm FinePix S5 Pro Sigma SD14 Sigma SD1 Merrill +14 more
Sergey_Green
Sergey_Green Forum Pro • Posts: 12,012
Meh ..
2

Tiger1 wrote:

Sergey_Green wrote:

Tiger1 wrote:

Now why do you think that anyone would care about the aperture diameter? The aperture diameter is only relevant when it is coupled to the focal length because as a photographer I actually measure light intensity (or luminosity) when I use a light meter. It actually gives me an F stop and a shutter speed. It does not give me an aperture diameter and then asks me for a focal length or vice versa. So f/2 IS f/2 when it comes to taking photos! Isn't that what this whole website is about? It is not about people like you getting so pedantic as to confuse everybody about what really is important.

The aperture diameter only explains why, but of course no-one should care what the exact size is. However, as a photographer, were you to shoot with different formats, would you care what your pics would look like at the end. After all, f/2 from FT and f/2 from FF are hardly the same. Would that matter?

F/2 is F/2 no matter what the format when it comes to exposure - that is what I'm talking about.

As a photographer I am interested in getting the correct exposure.

And this alone tells me that you have no idea what you are talking about. First, I don't believe many people shoot in fully manual mode, not even pros. It is either (aperture,shutter) priority with exposure compensation when necessary, or plain old p-mode (I suspect your favourite). Secondly, I would not imagine someone would spend double for the sake of exposure when buying the likes of 35/1.4, 85/1.4, or any of the 105/135 DC lenses, not today. Those are mainly for the visual properties the images will have in them; blur, subject isolation, creamy bokeh, etc. So here you straight bold-faced disqualified your 'as a photographer' line, because from what you append further you clearly are not.

ISO, shutter speed and F stop determine exposure.

Yeah, and how exactly does the ISO determine the exposure, please enlighten us.

When it comes to DOF that is another matter. The effect of F stop on DOF will depend on the focal length of the lens. Because different formats have different angles of view, one has to change focal lengths to get the same perspective for each format.

Whatever depends on it is not the same between the formats when set to the same numeric values.

Changing the focal length at a given aperture will then affect DOF. To get equal DOF one has to increase ones aperture as the format gets smaller to retain the same perspective.

And so f/2 is not f/2, because one has to be changed from where the other is. And same goes for light, you get more light through the larger opening that you can squeeze at the same intensity through a smaller one - what a concept!

The F stop will still determine the exposure with the shutter speed for a given ISO.

Which is all adjusted and levelled to the format, with more added gain for the smaller sensor, and is completely irrelevant to this discussion.

So when it comes to EXPOSURE f/2=f/2=f/2 no matter what the format.

I think you need to practice with your p-mode a bit longer, and then come show us what else you have discovered. Whatever you are selling here is just not flying.

-- hide signature --

- sergey

bobn2
bobn2 Forum Pro • Posts: 63,469
Re: Bzzt.

Tiger1 wrote:

Tiger1 wrote:

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Sure.

Sensor size has little to do with enlargement.

It has *everything* to do with enlargement!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

Wow, just wow. It has everything to do with sensor size. Well, more accurately, it has everything to do with aperture diameter and saturation capacity.

By the way, were you ever going to get around to answering Bob's question? If not, is there any particular reason you don't want to answer?

I'm on my phone which limits what I can see image wise.
I have a social function after work so I won't get to my computer for another 24hrs.
That's why I can't answer Uncle Bob's question....yet.

You didn't answer Uncle Bob's other question either (maybe it wasn't directed at you) - you seem very concerned about 'correct' exposure at some ISO. If two cameras have 'equal' ISO, what is it that is 'equal'?

-- hide signature --

Bob

bobn2
bobn2 Forum Pro • Posts: 63,469
Re: Meh ..
1

Sergey_Green wrote:

First, I don't believe many people shoot in fully manual mode, not even pros.

I do, most of the time. I lent my camera to a pro, it came back set in P mode.

-- hide signature --

Bob

Sergey_Green
Sergey_Green Forum Pro • Posts: 12,012
Does not mean he or she used it in p-mode, it was just to be polite to you ;)
1

bobn2 wrote:

Sergey_Green wrote:

First, I don't believe many people shoot in fully manual mode, not even pros.

I do, most of the time. I lent my camera to a pro, it came back set in P mode.

So you are glutton for punishment, it is very unusual these days when handling the cameras - why? If blur is important to you you set the aperture, camera will adjust the shutter speed. If you are after stopping the motion, set the shutter speed, and the camera will do the rest with the aperture. All there is to it. Use exposure compensation in both cases if you are shooting on the white snow, sunsets at the beach, or at night (for example). In fact with most modern cameras even that is seldom necessary.

What is important, however, is readiness and the awareness of how the images will look when downloaded and opened up on your desktop. I just don's see how m-mode fully helps you with it.

-- hide signature --

- sergey

Tiger1 Contributing Member • Posts: 552
Re: Bzzt.
1

Tiger1 wrote:

Tiger1 wrote:

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Sure.

Sensor size has little to do with enlargement.

It has *everything* to do with enlargement!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

Wow, just wow. It has everything to do with sensor size. Well, more accurately, it has everything to do with aperture diameter and saturation capacity.

By the way, were you ever going to get around to answering Bob's question? If not, is there any particular reason you don't want to answer?

I'm on my phone which limits what I can see image wise.
I have a social function after work so I won't get to my computer for another 24hrs.
That's why I can't answer Uncle Bob's question....yet.

You didn't answer Uncle Bob's other question either (maybe it wasn't directed at you) - you seem very concerned about 'correct' exposure at some ISO. If two cameras have 'equal' ISO, what is it that is 'equal'?

Can't remember that question but anyhow I'll answer.
ISO measures the camera medium's (digital sensor or film) sensitivity to light.
It actually looks at sensitivity of light per unit area like I've been saying rather than total light over sensor or film. So cameras of equal iso will have equally sensitive sensors.

Next...

 Tiger1's gear list:Tiger1's gear list
Sony RX1 Canon EOS 5D Mark II Fujifilm FinePix S5 Pro Sigma SD14 Sigma SD1 Merrill +14 more
windsprite
windsprite Senior Member • Posts: 2,730
Re: Exactly
1

Art_P wrote:

but I hardly ever display at 8', so why waste all that ink?

Right on!  It seems to me this what equivalence is about.  If four thirds (or whatever format or whatever lens) does the job you require, there's no need to choose larger, more expensive gear that does more than that.

Besides, a balloon blown up to 2' will last longer than one blown up to 8' And those old shriveled balloons look so sad

Speak up, son!  Old shriveled whats, you say?!

Julie

 windsprite's gear list:windsprite's gear list
Fujifilm FinePix F100fd Fujifilm FinePix F550 EXR Panasonic Lumix DMC-FZ200 Nikon D2H Nikon D300 +47 more
Jay Ell Regular Member • Posts: 256
Re: you wouldn't want

Tiger1 wrote:

Sensor size has little to do with enlargement.

I am puzzled (no surprise there) - in film, if I used a regular SLR (135 film), I had to enlarge the captured image certain amount to make the output image say 30cm by 20 cm, but if I used a medium format camera I had to enlarge the captured image much less, so size of the film dictated how much I needed to enlarge the image to make the print of desired size. I don't understand why it would be different for digital - please help me!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.

But I've read that the Sigma Merrill pixel has about 25 electron read noise, and the other modern cameras have just about 2 to 4 electron read noise - it is something to do with no correlated double sampling (or something like that) in the Sigma and having three photodetectors per pixel. And unless I'm badly informed, the Sigmas colour transformation increases noise even more. Have I been misinformed?

Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

I've read that the formula for signal in an image in digital is: p*pixel count where the p = pixel signal level and that the noise in general is sqrt((s^2 + r^2)*pixel count), where s = shot noise = sqrt(p) and r=read noise. I don't understand how what you say and these formulas would agree - I know there must be something wrong in the formulas - I'd appreciate your guidance!

-- hide signature --

Copyright © Jay Ell

Jay Ell Regular Member • Posts: 256
Re: Bzzt.

Tiger1 wrote:

.

ISO measures the camera medium's (digital sensor or film) sensitivity to light.

I've understand that the sensors have a fixed sensitivity and typically capture about 50% of the light that goes past the colour filter. I've read this from many places. I must have misunderstood something - maybe you can help?

It actually looks at sensitivity of light per unit area like I've been saying rather than total light over sensor or film. So cameras of equal iso will have equally sensitive sensors.

I had the chance of looking at the ISO standard and all it talked about was about JPEG-images - I didn't see anything about RAW - does this matter?

-- hide signature --

Copyright © Jay Ell

bobn2
bobn2 Forum Pro • Posts: 63,469
Re: Bzzt.
1

Tiger1 wrote:

Tiger1 wrote:

Tiger1 wrote:

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Sure.

Sensor size has little to do with enlargement.

It has *everything* to do with enlargement!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

Wow, just wow. It has everything to do with sensor size. Well, more accurately, it has everything to do with aperture diameter and saturation capacity.

By the way, were you ever going to get around to answering Bob's question? If not, is there any particular reason you don't want to answer?

I'm on my phone which limits what I can see image wise.
I have a social function after work so I won't get to my computer for another 24hrs.
That's why I can't answer Uncle Bob's question....yet.

You didn't answer Uncle Bob's other question either (maybe it wasn't directed at you) - you seem very concerned about 'correct' exposure at some ISO. If two cameras have 'equal' ISO, what is it that is 'equal'?

Can't remember that question but anyhow I'll answer.
ISO measures the camera medium's (digital sensor or film) sensitivity to light.

So, does that mean that every 100 ISO sensor/camera/setting has the same sensitivity to light?

It actually looks at sensitivity of light per unit area like I've been saying rather than total light over sensor or film. So cameras of equal iso will have equally sensitive sensors.

Oh, I see you had an answer for that. So you're saying that an E-M5 and D3s sensor are equally sensitive to light? How is sensitivity to light measured? What would be the proper ISO units?

Next...

We'll stay on this one until you've got it right.

-- hide signature --

Bob

windsprite
windsprite Senior Member • Posts: 2,730
Re: you wouldn't want
1

Tiger1 wrote:

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Yes, of course. Thanks for the correction.  I saw somebody else make that mistake on this forum in the past day or so, and I was wondering how long it would take me to do the same thing.  Not very long, I guess!

Sensor size has little to do with enlargement.

I'm sure this is incorrect.

Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size

See above.

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.

You're making this more complicated than necessary, bringing in unrelated issues and ignoring the relevant ones.

Forget about different formats and pixel counts for a minute and stick to one format, any one. Why does one try to put more light on a sensor?

Try this thought experiment.  First photograph a solid-colored, featureless surface at base ISO.  Then take away several stops of light (by closing down the aperture or shortening the shutter speed or reducing the scene luminance, or by some combination of the three).  Raise the ISO to match the output brightness of the base-ISO image, then print the two to the same size.  Am I wrong in thinking that the one made with more light is going to have less noise and better color, among other niceties?

Now do this with several different sensor sizes (let's assume the same manufacturer, so the issue is not clouded by differences in color palette and whatnot; you can also tweak the MP count however you like). Do one set with the same light density (exposure) on each camera and then another set with the same total light on each camera (that is: progressively lower light density, forcing you to use higher ISO, as the sensor gets larger). Same print size for each one. What do you think will happen? I think the latter set will look pretty much the same across the board, and if you line up the former set in order of ascending image quality, I think it will correlate with sensor size, smallest to largest.

Weird coincidence, huh?

If you have a hard time visualizing what might happen to a solid color in these cirumstances, go to one of the DPR studio comparison widgets and plug in a camera.  Look at the full scene (not the 100% crop) at base ISO and then at something like ISO 12800, and you will see the colors go grey and lifeless.

And to re-quote one of your comments from above, this time including the part in parenthesis:

"Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!)."

I'm really not a tech-y person, so I don't know a lot about photosites and all that, but from a practical standpoint, I think you can only pile photons so high on a sensor.  To collect more of them, you have to spread out over a larger area.  I vaguely remember reading of things like well depth which affect efficiency, but it seems to me that total area must be by far the more significant factor, which is I think what Bob and the other gents have been saying.  I've been shooting four thirds since 2005 and micro four thirds since a few years ago, and I also shoot Nikon FX and DX, as well as ASP-C mirrorless (NEX) and an FZ200 -- yes, I like cameras, and I'm pretty brand/format agnostic! -- and my experience over the years, plus the DxO numbers and various shootouts I've seen, bear this out.

Julie

 windsprite's gear list:windsprite's gear list
Fujifilm FinePix F100fd Fujifilm FinePix F550 EXR Panasonic Lumix DMC-FZ200 Nikon D2H Nikon D300 +47 more
Mikael Risedal
Mikael Risedal Veteran Member • Posts: 4,625
Re: Bzzt.

Tiger1 wrote:

Tiger1 wrote:

Art_P wrote:

all that paint on the smaller surface- it will just run and drip.

Looking at it another way: someone has a 1000sf house, someone else has a 4000sf house.

The guy w the 1000sf house wants to be just as warm as the guy w the 4000sf home, so he puts in the same size furnace, and sets it to run just as long as the one in the 4000sf house... then he can't understand why his friend's house is a comfortable 70F, while his house is pushing 120F

Say you buy a bag of balloons which can be blown up to eight feet tall. You blow up one to a height of two feet and draw a picture on the balloon using a stencil and some magic markers. I blow up another balloon to a height of four feet and stencil on the same picture, but it's proportionately larger to fill up the same percentage of the surface area as on your two-foot balloon. The density of marker ink is the same on your balloon and mine, but I use four times as much ink, right?

Now somebody comes along and thinks the balloons are beautiful, and they want to blow them up to eight feet tall and display them. Which balloon will now have the higher density of ink per unit of surface area, yours or mine? Which balloon is likely to look better?

This is what people keep missing. Yes, f/2 is f/2, and it puts the same density of light on the sensor. For the ten thousandth time, nobody denies that. However, you have to blow up the image from the smaller sensor a lot more than you do the image from the larger sensor in order to get the same display size. What matters is the density of protons used to form the final image, not the density used to form the image on the sensor.

Edit: All this is not to say that the smaller sensor is inferior, and anybody who thinks this is the natural conclusion is missing the whole point of the discussion. I don't have time to explain why, but a little thinking ought to reveal the answer.

Julie

I know what you are saying but you are not accurate.
Protons are subatomic particles that have little to do with image capture. Maybe you meant photons!

Sure.

Sensor size has little to do with enlargement.

It has *everything* to do with enlargement!

The first Canon D30 had an aps sensor of 3MP. The sony digicam has a tiny sensor comparatively but has 20MP. You can enlarge the sony pictures far more than the canons. A sigma merrill camera has an aps-c sized sensor but you can enlarge the images from it far more than a Nikon D3 which has a FF sensor, despite the texta balloon example you gave us.
Enlargement in the digital era is all about numbers of pixels coupled with cleanliness/sharpness per pixel. It has little to do with sensor size (although I have been arguing that the larger sensors can have larger photosites which trap more photons and you can have more of them to boot!).

Wow, just wow. It has everything to do with sensor size. Well, more accurately, it has everything to do with aperture diameter and saturation capacity.

By the way, were you ever going to get around to answering Bob's question? If not, is there any particular reason you don't want to answer?

I'm on my phone which limits what I can see image wise.
I have a social function after work so I won't get to my computer for another 24hrs.
That's why I can't answer Uncle Bob's question....yet.

I suggest you try to learn from BOB instead

-- hide signature --

Member of Swedish Photographers Association since 1984
Canon, Hasselblad, Leica,Nikon, Linhoff, Sinar
Ernest Hemingway to Irving Penn:?“Your photos are really good. What camera do you use?”?Irving Penn to Ernest Hemingway:?“Your novels are excellent. What typewriter do you use?”

Keyboard shortcuts:
FForum MMy threads