jthomas, I thought your picture most helpful, and took the liberty to alter it slightly for what I think adds to the understanding...please forgive my liberties with your image, as well as my own crude adoption:
An image on a full frame will be seen as this:
While on a crop camera, though the lens is not providing more magnification, the effect is similar. In order to get the subject in the full view of the crop camera, one needs to widen the view. Thus the same lens, on each camera, captures a different field of view, requiring a wide lens on the crop camera for the same view. Likewise, this has the opposite 'benefit' when using a zoom lens, as the crop camera offers more 'zoom' if you will:
forgive the artwork here, I had only powerpoint at my disposal...blame it on the tool, not the artist
jthomas, I thought your picture most helpful, and took the liberty to alter it slightly for what I think adds to the understanding...please forgive my liberties with your image, as well as my own crude adoption:
An image on a full frame will be seen as this:
While on a crop camera, though the lens is not providing more magnification, the effect is similar. In order to get the subject in the full view of the crop camera, one needs to widen the view. Thus the same lens, on each camera, captures a different field of view, requiring a wide lens on the crop camera for the same view. Likewise, this has the opposite 'benefit' when using a zoom lens, as the crop camera offers more 'zoom' if you will:
forgive the artwork here, I had only powerpoint at my disposal...blame it on the tool, not the artist
Good Morning
Kinda like viewing a tree side by side through 2 different windows. One measures 36" x 24" and the second measures 24" x 15". The tree is still the same size and distance in both windows, however, the view through the second window is showing only part of the tree.
Have a good day
Jim...
Good Morning
Kinda like viewing a tree side by side through 2 different windows. One measures 36" x 24" and the second measures 24" x 15". The tree is still the same size and distance in both windows, however, the view through the second window is showing only part of the tree.
Have a good day
Jim...
You may be viewing a smaller portion of the tree, but you are viewing it at greater magnification. That article that you referenced in your previous post describes it here:
"The D100 has a 1.5x FOV Crop. What does this mean? Well, it means any 35mm lens you put on your D100, will automatically magnify your image by 1.5. Looking at it another way, it also means you add 50% more focal length or "zoom power". The smaller the CCD in relation to film, the larger the magnification ratio. Again, why? Since the CCD is smaller than the 35mm film size, the image is magnified automatically, because a 35mm lens that is being put on it, has a much larger image circle. "
Life is not measured by the breaths you take, but by the moments that take your breath away...... " I wasn't born in Oklahoma, but I got here as fast as I could! "
You may be viewing a smaller portion of the tree, but you are viewing it at greater magnification. That article that you referenced in your previous post describes it here:
"The D100 has a 1.5x FOV Crop. What does this mean? Well, it means any 35mm lens you put on your D100, will automatically magnify your image by 1.5. Looking at it another way, it also means you add 50% more focal length or "zoom power". The smaller the CCD in relation to film, the larger the magnification ratio. Again, why? Since the CCD is smaller than the 35mm film size, the image is magnified automatically, because a 35mm lens that is being put on it, has a much larger image circle. "
Magnify
Cheers,
-joel
Good Morning
So then basically, the smaller the sensor the more magnification ? If using the Geometry that was mentioned in the article to obtain the x factor, you could theoretically design a small enough sensor to have an equivalent of say 2000mm using an 500mm lens ? That would mean a 4x crop as compared to a 1.6 crop on most cameras today. Is that a correct statement ?
Have a good day
Jim...
Good Morning
So then basically, the smaller the sensor the more magnification ? If using the Geometry that was mentioned in the article to obtain the x factor, you could theoretically design a small enough sensor to have an equivalent of say 2000mm using an 500mm lens ? That would mean a 4x crop as compared to a 1.6 crop on most cameras today. Is that a correct statement ?
Have a good day
Jim...
Yup. The only catch is that sensors with higher pixel densities tend not to produce the same image quality as sensors with bigger pixels. By quality, I'm talking more in terms of color tones and maybe noise, as opposed to sharpness. Sharpness to me is dictated by focus and pixel density, both of which you can get with a dense sensor. But there is a point of diminishing returns by using a smaller sensor.
Good Afternoon
Very Interesting. The text below was taken from another web site where trolls are known to roam
Have a good afternoon
Jim...
John down under - 2 weeks ago
Myth: Higher crop factor camera (smaller image sensor) means greater magnification for the same focal length lens.
Reason: Magnification has a specific meaning in photography. It means the size (eg in mm) of the subject projected onto the image sensor plane (or film plane) compared to the actual size of the subject itself (eg in mm). The size of the sensor is irrelevant as it doesn't affect the size of the projection. 1:1 magnification (true macro) means that an object that is x mm wide will be projected at a size of the same x mm at the sensor plane. The crop factor of the camera will then determine how much of the sensor/frame is filled by that subject.
In practical terms: All that aside, using a lens of the same FL at the same distance from the subject with a more cropped camera will result in the subject filling more of the captured frame. It's common to state what FL lens would be needed on a FF camera to provide the same framing from the same shooting distance as the lens in question on the cropped body. The issue of magnification is only one of terminology.
Myth: f-stop is the same as aperture.
Reason: The aperture is the size (diameter) of the iris/opening between the aperture blades that lets light through the lens. f-stop or f/ratio is a ratio between the focal length of the lens and the size of the aperture.
In practical terms: f-stop is easy to set and know, whereas aperture has to be calculated, so aperture isn't generally used. However, image sensor pixel density aside, depth of field is largely determined by focus distance and aperture (not f-stop). Larger focus distance mens larger DOF. Larger aperture means smaller DOF. For a given FL, increasing the f-stop reduces the aperture size and increases DOF. Likewise, for a given f-stop, increasing FL increases the size of the aperture and decreases DOF. In both cases, the same focus distance is assumed.
Myth: When shooting from the same position, changing the lens FL or changing the camera crop factor change the image perspective.
Reason: Perspective is the relationship between the elements of the image, not how the image is framed. When shooting from the same spot, the elements of the image are exactly the same with respect to each other as each path from the lens to any part of the scene can't change.
In practical terms: A longer lens from the same position won't foreshorten the perspective when compared with using a wider angle lens on a cropped body from the same position. If the f-stop isn't changed, DOF will change, with the longer lens resulting in a shallower DOF. However, the relative sizes of elements in the scene won't change, even if the framing of the scene changes from this same position because the difference in FL doesn't match the change in crop size. Paths of light from the parts of the scene to the camera can't alter when shooting from the same position and change perspective.
Myth: More cropped cameras with the same subject framing don't provide greater DOF for the same f-stop.
Reason: To keep the subject framing the same while changing the camera crop size, you either change the FL while keeping the camera in the same place, or move the camera while keeping the lens FL the same. Keeping the camera in the same place not only retains subject framing, but also retains the perspective in the scene. The shorter FL you need on the more cropped camera for the same framing as the longer lens on the les cropped camera means that for a constant f-stop, the longer lens has a larger aperture, meaning a shallower DOF on the less cropped body. If the same FL lens is used and subject framing is retained by backing up with the more cropped body (which also changes the perspective), the increased focus distance means a greater DOF for the more cropped body.
In practical terms: It's important to specify f-stop and framing (and to some extent perspective) conditions when stating whether DOF is different for different crop cameras.
--
Cheers from John from Adelaide, South Australia
John Harvey Photography http://johnharvey.com.au
Canon 40D, Canon 20D & Fuji F10
Yup. The only catch is that sensors with higher pixel densities tend not to produce the same image quality as sensors with bigger pixels. By quality, I'm talking more in terms of color tones and maybe noise, as opposed to sharpness. Sharpness to me is dictated by focus and pixel density, both of which you can get with a dense sensor. But there is a point of diminishing returns by using a smaller sensor.
From what I have read it is actually the noise which is manifested in the bleeding of color data between ajacent pixels. They (Nikon/Canon) have gotten better with it as witnessed by the progression from the D30(3 MegaPixel) to 450D (12 MegaPixel) sensors on the same sensor real estate but there exists probably a limit to how far they can go.
Rather than try to agree with any particular group, I will attempt to explain several different understandings and misunderstandings, and define terminology (some new) to which I will ask the reader to accept for the sake of the explanation.
Once we start talking in common terms, I think everything will fall into place. The key will be the understanding and acceptance of the terms, especially as they are used in the context of the discussion.
I will be showing examples* to actually demonstrate the principles involved. Rather than try to convince anyone that there is a single way to look at these issues, I will try to explain why differing views exist. The point of my discussion will be that of understanding relationships and the reader will be allowed to draw their own conclusions.
(*The examples will include photographs, illustrations and simple mathematics. All should be fairly simple for people to prove and duplicate for themselves, if necessary.)
jthomas, I thought your picture most helpful, and took the liberty to alter it slightly for what I think adds to the understanding...please forgive my liberties with your image, as well as my own crude adoption:
An image on a full frame will be seen as this:
While on a crop camera, though the lens is not providing more magnification, the effect is similar. In order to get the subject in the full view of the crop camera, one needs to widen the view. Thus the same lens, on each camera, captures a different field of view, requiring a wide lens on the crop camera for the same view. Likewise, this has the opposite 'benefit' when using a zoom lens, as the crop camera offers more 'zoom' if you will:
forgive the artwork here, I had only powerpoint at my disposal...blame it on the tool, not the artist
WOW, Image C is like most of my pics.
If I get a full frame camera will it stop all the heads being cutoff in all my photos?
WOW, Image C is like most of my pics.
If I get a full frame camera will it stop all the heads being cutoff in all my photos?
you bet..but you have to first sign the secret agreement NOT to push the 'world peace' button on the back of that new camera...if everyone pushed that...well it would put all those war press photogs out of business you know.
Morning Folks
The following link provides a very good in depth look at these issues. Make a pot of coffee, turn off your cell phones and prepare to spend some time reading this article. It is a bit lengthy, but very detailed.
Have a good day
Jim... http://www.digitaldingus.com/articles/fov/fovef.php
Well, I see that this author has several diagrams similar to mine, but his explanation is much longer. He seems to subscribe to the old principle "never say in ten words what you can say in 100".
Seriously, though, he does discuss more aspects of the problem than I did in my brief post. In my view, he also overcomplicates it.
Well, I see that this author has several diagrams similar to mine, but his explanation is much longer. He seems to subscribe to the old principle "never say in ten words what you can say in 100".
Seriously, though, he does discuss more aspects of the problem than I did in my brief post. In my view, he also overcomplicates it.
Good Afternoon The diagrams are similiar to yours, mine, and countless others as well, & the longer, detailed explanation may be necessary to some people that still had questions about that issue
Comments
An image on a full frame will be seen as this:
While on a crop camera, though the lens is not providing more magnification, the effect is similar. In order to get the subject in the full view of the crop camera, one needs to widen the view. Thus the same lens, on each camera, captures a different field of view, requiring a wide lens on the crop camera for the same view. Likewise, this has the opposite 'benefit' when using a zoom lens, as the crop camera offers more 'zoom' if you will:
forgive the artwork here, I had only powerpoint at my disposal...blame it on the tool, not the artist
Good Morning
Kinda like viewing a tree side by side through 2 different windows. One measures 36" x 24" and the second measures 24" x 15". The tree is still the same size and distance in both windows, however, the view through the second window is showing only part of the tree.
Have a good day
Jim...
You may be viewing a smaller portion of the tree, but you are viewing it at greater magnification. That article that you referenced in your previous post describes it here:
"The D100 has a 1.5x FOV Crop. What does this mean? Well, it means any 35mm lens you put on your D100, will automatically magnify your image by 1.5. Looking at it another way, it also means you add 50% more focal length or "zoom power". The smaller the CCD in relation to film, the larger the magnification ratio. Again, why? Since the CCD is smaller than the 35mm film size, the image is magnified automatically, because a 35mm lens that is being put on it, has a much larger image circle. "
Magnify
Cheers,
-joel
Link to my Smugmug site
dak.smugmug.com
not rocket science..
" I wasn't born in Oklahoma, but I got here as fast as I could! "
http://k2c-ridge.smugmug.com/
Member NAPP
Good Morning
So then basically, the smaller the sensor the more magnification ? If using the Geometry that was mentioned in the article to obtain the x factor, you could theoretically design a small enough sensor to have an equivalent of say 2000mm using an 500mm lens ? That would mean a 4x crop as compared to a 1.6 crop on most cameras today. Is that a correct statement ?
Have a good day
Jim...
Yup. The only catch is that sensors with higher pixel densities tend not to produce the same image quality as sensors with bigger pixels. By quality, I'm talking more in terms of color tones and maybe noise, as opposed to sharpness. Sharpness to me is dictated by focus and pixel density, both of which you can get with a dense sensor. But there is a point of diminishing returns by using a smaller sensor.
Link to my Smugmug site
Very Interesting. The text below was taken from another web site where trolls are known to roam
Have a good afternoon
Jim...
John down under - 2 weeks ago
Myth: Higher crop factor camera (smaller image sensor) means greater magnification for the same focal length lens.
Reason: Magnification has a specific meaning in photography. It means the size (eg in mm) of the subject projected onto the image sensor plane (or film plane) compared to the actual size of the subject itself (eg in mm). The size of the sensor is irrelevant as it doesn't affect the size of the projection. 1:1 magnification (true macro) means that an object that is x mm wide will be projected at a size of the same x mm at the sensor plane. The crop factor of the camera will then determine how much of the sensor/frame is filled by that subject.
In practical terms: All that aside, using a lens of the same FL at the same distance from the subject with a more cropped camera will result in the subject filling more of the captured frame. It's common to state what FL lens would be needed on a FF camera to provide the same framing from the same shooting distance as the lens in question on the cropped body. The issue of magnification is only one of terminology.
Myth: f-stop is the same as aperture.
Reason: The aperture is the size (diameter) of the iris/opening between the aperture blades that lets light through the lens. f-stop or f/ratio is a ratio between the focal length of the lens and the size of the aperture.
In practical terms: f-stop is easy to set and know, whereas aperture has to be calculated, so aperture isn't generally used. However, image sensor pixel density aside, depth of field is largely determined by focus distance and aperture (not f-stop). Larger focus distance mens larger DOF. Larger aperture means smaller DOF. For a given FL, increasing the f-stop reduces the aperture size and increases DOF. Likewise, for a given f-stop, increasing FL increases the size of the aperture and decreases DOF. In both cases, the same focus distance is assumed.
Myth: When shooting from the same position, changing the lens FL or changing the camera crop factor change the image perspective.
Reason: Perspective is the relationship between the elements of the image, not how the image is framed. When shooting from the same spot, the elements of the image are exactly the same with respect to each other as each path from the lens to any part of the scene can't change.
In practical terms: A longer lens from the same position won't foreshorten the perspective when compared with using a wider angle lens on a cropped body from the same position. If the f-stop isn't changed, DOF will change, with the longer lens resulting in a shallower DOF. However, the relative sizes of elements in the scene won't change, even if the framing of the scene changes from this same position because the difference in FL doesn't match the change in crop size. Paths of light from the parts of the scene to the camera can't alter when shooting from the same position and change perspective.
Myth: More cropped cameras with the same subject framing don't provide greater DOF for the same f-stop.
Reason: To keep the subject framing the same while changing the camera crop size, you either change the FL while keeping the camera in the same place, or move the camera while keeping the lens FL the same. Keeping the camera in the same place not only retains subject framing, but also retains the perspective in the scene. The shorter FL you need on the more cropped camera for the same framing as the longer lens on the les cropped camera means that for a constant f-stop, the longer lens has a larger aperture, meaning a shallower DOF on the less cropped body. If the same FL lens is used and subject framing is retained by backing up with the more cropped body (which also changes the perspective), the increased focus distance means a greater DOF for the more cropped body.
In practical terms: It's important to specify f-stop and framing (and to some extent perspective) conditions when stating whether DOF is different for different crop cameras.
--
Cheers from John from Adelaide, South Australia
John Harvey Photography http://johnharvey.com.au
Canon 40D, Canon 20D & Fuji F10
From what I have read it is actually the noise which is manifested in the bleeding of color data between ajacent pixels. They (Nikon/Canon) have gotten better with it as witnessed by the progression from the D30(3 MegaPixel) to 450D (12 MegaPixel) sensors on the same sensor real estate but there exists probably a limit to how far they can go.
Mike Mattix
Tulsa, OK
"There are always three sides to every story. Yours, mine, and the truth" - Unknown
Once we start talking in common terms, I think everything will fall into place. The key will be the understanding and acceptance of the terms, especially as they are used in the context of the discussion.
I will be showing examples* to actually demonstrate the principles involved. Rather than try to convince anyone that there is a single way to look at these issues, I will try to explain why differing views exist. The point of my discussion will be that of understanding relationships and the reader will be allowed to draw their own conclusions.
(*The examples will include photographs, illustrations and simple mathematics. All should be fairly simple for people to prove and duplicate for themselves, if necessary.)
Moderator of the Cameras and Accessories forums
WOW, Image C is like most of my pics.
If I get a full frame camera will it stop all the heads being cutoff in all my photos?
you bet..but you have to first sign the secret agreement NOT to push the 'world peace' button on the back of that new camera...if everyone pushed that...well it would put all those war press photogs out of business you know.
...possibly, but it might be cheaper to have them all duck a bit.
This is an interesting article
Canon EOS 30D, Canon 50mm f/1.4, Sigma 70-200 f/2.8, Sigma 18-50 f/2.8, Tokina 12-24 f/4. Sigma 1.4 TC, Feisol 3401 Tripod + Feisol ballhead, Metz 58 AF-1 C, ebay triggers.
Seriously, though, he does discuss more aspects of the problem than I did in my brief post. In my view, he also overcomplicates it.
Ulrik,
Yes, that is an excellent article and I will reference it as one of my sources for my discussion.
Moderator of the Cameras and Accessories forums
Good Morning,
Yes that is a very interesting article. Perhaps a more appropriate name would be a 1.5x or 1.6x DOF crop
Have a good day
Jim...
Good Afternoon
The diagrams are similiar to yours, mine, and countless others as well, & the longer, detailed explanation may be necessary to some people that still had questions about that issue
Have a good afternoon
Jim...