125 replies to this topic

[herbko]

A lens that produces 1:1 (Canon 100mm, Tamron 90mm, not the Canon 50mm which is 1:2) on 35mm format will produce greater apparent magnification on a crop sensor camera.  We all know of course that it's cropping rather than magnification that's happening here, the the fact remains that absolute size in mm of the image on the sensor will be different between the EF-S and the EF lens, ergo the degree of magnification is in fact different.

<{POST_SNAPBACK}>

Here's the point of confusion that I was trying to point out. There are TWO magnification steps between the subject and your print: subject to sensor, and sensor to print. The lens makers are just giving the spec for their part which is subject to sensor. 1:1 means subject size equal image size on the sensor and does not depend on sensor size. The 1:1 EF lens and the 1:1 EF-S lens has the SAME magnification. Canon can change the 100mm EF lens to EF-S tomorrow by changing the mount and not the glass and the 1:1 spec, the magnification, would NOT change.

The magnification that is different is going from sensor to print which is NOT spec by the lens maker.

[Kasey]

Well, I don't take it so far as the print in my analysis. Lets just go as far as the viewfinder. When I look through the viewfinder of a 1:1 Nikkor mounted on my F100, what I see is lower magnification than the same lens mounted to my D2x - on the d2x it IS beyond 1:1 in my viewfinder.

I think we are saying similar things differently, but my real question is answered by Herb - the 1:1 lenses give identical magnification.

Here is food for thought:
A 1:1 medium format lens is mounted to a 35mm camera. The viewfinder will project a 4:1 (approx) magnification of the subject. If that same lens were designed native to the 35mm, I think that the lens designer would market it as a 4:1 lens. I disagree that the stated ratio of the lens has nothing to do with the size of the medium on which it projects.

A corollary to that - the projected image of a 100mm macro is at least 35X35, yet it is the 24X35 crop that is 1:1. Clearly the lens designers do consider the medium and the viewfinder.

[Rocha]

Well, I don't take it so far as the print in my analysis.  Lets just go as far as the viewfinder.  When I look through the viewfinder of a 1:1 Nikkor mounted on my F100, what I see is lower magnification than the same lens mounted to my D2x - on the d2x it IS beyond 1:1 in my viewfinder.

I think we are saying similar things differently, but my real question is answered by Herb - the 1:1 lenses give identical magnification.

Here is food for thought:
A 1:1 medium format lens is mounted to a 35mm camera.  The viewfinder will project a 4:1 (approx) magnification of the subject.  If that same lens were designed native to the 35mm, I think that the lens designer would market it as a 4:1 lens.  I disagree that the stated ratio of the lens has nothing to do with the size of the medium on which it projects. 

A corollary to that - the projected image of a 100mm macro is at least 35X35, yet it is the 24X35 crop that is 1:1.  Clearly the lens designers do consider the medium and the viewfinder.

<{POST_SNAPBACK}>

Kasey, taking your medium format example, a real 4:1 lens can fill the frame with an object four times smaller than the camera's sensor. That does not happen with your medium format example, if you take a medium format 1:1 lens and mount it on a 35mm camera it will not be able to fill the frame with an object smaller than 35mm. The numbers (1:1, 4:1, etc) mean subject to sensor ratio, not subject to viewfinder ratio, and I think you are mixing those numbers.

[Kasey]

OK - I think Luiz and Herb are right from an optical standpoint, and we are talking lens optics after all. But in a practical sense, what I see in the viewfinder IS what my sensor sees, and the same lens on a smaller format yields greater magnification. If the resolving power of the APS chip is equivalent to a 35mm slide, the net effect is a "crop" with full 35 mm resolution. Same as putting a 1.6X teleconverter on my 35mm lens - yields greater than 1:1. Thanks for clearing up this point!

[Jolly]

Rob & Paul,

this was exactly my point. Soft corners increase with larger FOV lenses and with high resolution cameras. IMO it is not predicted by the sensor size physically. As Paul said, you get soft corners with every extreme wideagnle and high resolution camera.

@Kasey:
See it simple, 1:1 means nothing more or less than this: captured subject has the same size on the sensor/film like in real life, that's it!

in other words:
You have two images. One image is in real world in front of the lens. The other image is behind the lens, projected on your sensor/film. 1:1 means that everything has the same size in both images.

If your sensor is 20mm x 20mm, a subject with 20mm x 20mm will fill the frame.
if your sensor is 36mm x 24mm, a subject with 36mm x 24mm will fill the frame.
But the sensor size has nothing to do with the magnification ratio. If it is 1:1, it is always 1:1, no matter on what sensor/camera you are going to mount it.

Only thing important to us when using smaller sensors: If you shoot a subject which fills the APS-C sensor with 1:1, you would need a 1,6:1 lens on full frame in order to get the same subject to fill the frame (final print).

Julian

[Phil Rudin]

Well, I don't take it so far as the print in my analysis.  Lets just go as far as the viewfinder.  When I look through the viewfinder of a 1:1 Nikkor mounted on my F100, what I see is lower magnification than the same lens mounted to my D2x - on the d2x it IS beyond 1:1 in my viewfinder.

I think we are saying similar things differently, but my real question is answered by Herb - the 1:1 lenses give identical magnification.

Here is food for thought:
A 1:1 medium format lens is mounted to a 35mm camera.  The viewfinder will project a 4:1 (approx) magnification of the subject.  If that same lens were designed native to the 35mm, I think that the lens designer would market it as a 4:1 lens.  I disagree that the stated ratio of the lens has nothing to do with the size of the medium on which it projects. 

A corollary to that - the projected image of a 100mm macro is at least 35X35, yet it is the 24X35 crop that is 1:1.  Clearly the lens designers do consider the medium and the viewfinder.

<{POST_SNAPBACK}>

Life size, (1:1) is life size on any media be it APS-C sensor size or 8"x10" view camera and full frame is full frame when the size of the sensor or film is the size for which the lens was designed.
Regarding 4:1 magnification of the subject this is a bit misleading as well. when you go from 2:1 to 1:1 the area increase is four times not two times. The subject area is twice as wide and twice as tall, that adds up to four times the area of the 2:1 inage. If you go from 1:1 to 1:2 the image is twice as tall and twice as wide, which is four times as large. If you have a 5 MP camera and want the image to be twice as big that would be twice as wide and twice as tall or 20 MP. If you look at a 1:2 framer for a Nikonos compaired to a 1:1 the 1:1 is twice as tall and twice as wide, 1:2 same 1:3 three times as tall as 1:1 and three times as wide. These rules don't change between film and digital and they don't change between format sizes.

Phil

[Phil Rudin]

No, Julian, he may not argue if he finds the term misleading.  It's bloody well called full frame by everyone, so he'd better get used to it!  FWIW, tropical, your pentax 6*7 is crop sensor also, given that I shoot MF at 6*9.     

Anyway, I've previously posted brick wall shots on Wetpixel of the 17-40L at full frame re: corner sharpness.  Please don't make me do it again!  Wetpixel briefly consisted of nothing but peoples' wall shots - personally I like looking at fish and reefs and stuff better.

The point is this.  A lens like the 17-40L on a full frame DSLR will peform very nicely, if you stop it down a little.  If you pixel peep, the corners are still soft at f8 to f11, but not so you'd notice on an underwater shot (compared to the distortion and softness once a port is involved).  It's not a problem of digital lens vs film lens - it's a problem of the sensors on the Canon 1Ds series (and now hopefully the 5D) producing files of medium format quality, through a lens designed for 35mm film use.  In short, Canon's state of the art full frame sensors outressolve nearly all lenses.  The three I mentioned above are some of the few (third party) lenses that are good enough to match the current generation of sensors.  (They're not really suitable underwater as they're all manual focus/manual aperture - and I don't think the UW pics would be any sharper anyway).



I use the 17-40L on the 1Ds for 80% of my topside shooting.  It's not perfect (and I'm looking for a sharper wide lens as we speak), but it's pretty damn good IMHO.

<{POST_SNAPBACK}>

Bob, I know the common use of the term full frame is understood by most to mean 35 mm full frame. But if you will keep an open mind and go to this Kodak link you will see several full frame sensors made by Kodak and sold by Kodak as "full frame" sensors that are not the same size as 35 mm. Since Kodak makes them and Kodak sells them I feel Kodak would know what full frame means. To say that the 35 mm size is the only size just because it is the most common size is in fact wrong.
Phil

http://www.kodak.com...amilyMain.jhtml

[UWphotoNewbie]

Of course Herb Ko is right about the magnification factor. 1:1 is 1:1 no matter what camera you mount it on.

But I think the real question is what direction the DSLR is heading. With a less expensive full frame camera from Cannon will the 20D replacement be full frame too? and what will Nikon's response be? Will Nikon go to full frame or not? How about the smaller players? Olympus has bet on an even smaller format 4/3 with all new lenses as well.

Comparing the D2x and the 5D you have a pretty good comparison from a sensor point of view (although the D2x body has more features and more cost). Both are 12 mp but Nikon crams more mp into a smaller sensor.

On the APS side you get:

1. Effective magnification through crop factor (that goby I took at 12" from the port is bigger on the screen at 12mp that it would be with the FF setup).
2. Better corners with FF lenses. (You loose this advantage again when you go back to wide angle and need DX lenses).
3. Less expensive sensor
4. Somewhat smaller lenses (but the lenses I've seen aren't much smaller)
5. Better DOF (take this in combination with the crop factor and Macro shooting is much improved)

On the FF side you get:
1. Bigger viewfinder. (I haven't seen it yet but Phil raved about the 5D viewfinder)
2. Lower Noise (should be lower with biger photosites)
3. No specialty DX lenses for digital or film only.

It will be interesting to see if the 5D will turn out to have lower noise than the D2x or not or weather it even matters. DSLR noise is already so low that it might not even be much of an advantage.

Thoughts?

[herbko]

On the APS side you get:


5. Better DOF (take this in combination with the crop factor and Macro shooting is much improved)


Thoughts?

<{POST_SNAPBACK}>

Depending on your assumptions, #5 is wrong in the important case of DOF limited macro shots. I assume by better DOF you mean larger DOF. For a given resolution, larger sensors will let you use smaller apertures before diffraction limits the resolution. This more than offsets the effects of having a longer focal length lens (which decreses DOF) to achieve the same field of view. Larger sensors have a net advantage in macro shots where DOF is a limiting factor.

[herbko]

It will be interesting to see if the 5D will turn out to have lower noise than the D2x or not or weather it even matters. DSLR noise is already so low that it might not even be much of an advantage.

Thoughts?

<{POST_SNAPBACK}>

If you think the noise on your DSLR is better than needed, you can trade it off for lens performance by shooting at higher ISO and smaller aperture. It was part of the point I was trying to make earlier, about FF effectively gives you a stop in lens performance all else being equal.

[Kelpfish]

I just heard that Canon was just joking, there is no 5D

[Paul Kay]

Come on folks - the debate over FF vs smaller sensors will rage forever if we're not careful!

The bottom line is that the smaller sensor will finally run out of steam in the MPixel department whilst it will always be (theoretically) possible to cram more pixels into a bigger sensor! Base common sense.

Whether it is worth taking either format to its theory limited specification is another question.

With the 5D, Canon have (much to my surprise) decided to head for a semi-pro/enthusiasts FF camera which should be very well worth housing. I doubt very much whether most people are going to look at a large print from a D2X and compare it with a large print from a 5D and comment on the difference. It is us as photographers who will notice the difference in using the cameras and which camera you choose is based on many other factors than final output quality.

I actually think that we should spend more time looking at solving the optical problems of domes and even chromatic problems with flat ports than arguing about sensor size. As you may recall from earlier posts, I'm not satisfied by the wide-zooms currently available (the 17~40 is about the best I've tried) and will be very interested to see what developments take place here. If Canon or Nikon produce a zoom which has less optical shift as its zoomed, is of fast aperture and preferably has IS or VR then I would say that this would have a great deal more bearing on which camera to house than does sensor size or many of the other theoretical considerations.

I look forward to trying out a 5D if I can get my hands on one!

[Kasey]

Depending on your assumptions, #5 is wrong in the important case of DOF limited macro shots. I assume by better DOF you mean larger DOF. For a given resolution, larger sensors will let you use smaller apertures before diffraction limits the resolution. This more than offsets the effects of having a longer focal length lens (which decreses DOF) to achieve the same field of view. Larger sensors have a net advantage in macro shots where DOF is a limiting factor.

<{POST_SNAPBACK}>

No one replied to my question - if the EF-s 60mm macro is A) not smaller B) not cheaper - why would canon make this an EF-S lens??? ANy thoughts?

[Simon K.]

To get back on Topic: there is a Hands on Review at DP Review.

[Simon K.]

From the Hands on Review linked above:

My initial description of the EOS 5D when compared to the EOS 20D was 'chunkier', and I still think that's a fair comment. It's actually not that much larger than the EOS 20D, about 8 mm (⅓ inch) wider and taller but thanks to a remolded and grip (which now has a finger hook) and its extra weight (125 g / 4.4 oz) the EOS 5D does create the impression that it is both more substantial and more robust. Other than this the EOS 5D does look remarkably similar to the EOS 20D, even the control layout on the rear of the camera is virtually identical. The intention of course is to tempt existing EOS 20D owners to upgrade with the least amount of fuss

[MikeVeitch]

I just heard that Canon was just joking, there is no 5D

<{POST_SNAPBACK}>

Joe, what are you talking about? This thread has had nothing to do with the 5D for about 3 pages now......

[Phil Rudin]

No one replied to my question - if the EF-s 60mm macro is A) not smaller B) not cheaper - why would canon make this an EF-S lens???  ANy thoughts?

<{POST_SNAPBACK}>

My thoughts on your question are that the new 60 mm is as close as you can get to a 100 mm macro for 35 mm. Nearly the same angle of view and what appears to be life-size for the x 1.6 sensor. The 35 mm, 100 mm macro endsup having the angle of view of a 160 mm film lens and the 50 mm ends up at an 80 mm angle of view and is a 1:2 lens without the extension tube. Can't help but think that a lens designed for the x 1.6 sensor would also give advanced performance over the older film lenses.

Phil

[whitey]

Was just reading Reichmann's 5D review, here's a quote pertinent to our recent discussions...

Full Frame Good. Full Frame Bad.
Now, I know that the on-line forum natterers and nay-sayers are going to have a field-day debating the pros and cons of full-frame vs reduced frame. Well, all I can say is – walk a mile in the 5D's shoes and we'll see what you really think.

Anyone that shot film with an SLR prior to digital knows how frustrating looking though the smaller and dimmer viewfinders of most 1.5X and 1.6x digital cameras can be. Looking through the viewfinder of a full-frame camera like the 5D, by comparison, is like taking a whiff of pure oxygen. The image will be big, and bright, and yes, did I mention that it's full frame?

Which of course will be the topic de-jour online. Lots of folks will posture about how reduced frame cameras are better because they crop out the soft corners of some lenses. They'll also carry on about how 1.5X and 1.6X cameras give you greater reach with telephoto lenses (ya, right).

But, the reality is that with the exception of a handful of special lenses released over the past year or two that are designed for reduced frame cameras, the millions of lenses out there project a bigger image circle, and being able to use that image circle is a wonderful thing for a great many reasons. True, a high resolution full-frame camera like a 1Ds MKII, or now 5D, will mercilessly expose the true qualities of poorer lenses, but such is life. I don't know a single professional photographer who uses a reduced frame DSLR for any reason other than size and price, or because that's what's available in their preferred camera maker's lens mount. The 5D is going to alter that equation, and the industry is never going to be the same again.

Here's the link:

http://www.luminous-...-announce.shtml

If anyone still objects to me calling the 5D full frame by the way, I note that as well as everyone else in the known universe using this term, Canon uses it liberally on their 5D page.

http://consumer.usa....=11933&pageno=0

[Phil Rudin]

Was just reading Reichmann's 5D review, here's a quote pertinent to our recent discussions...

Full Frame Good. Full Frame Bad.
Now, I know that the on-line forum natterers and nay-sayers are going to have a field-day debating the pros and cons of full-frame vs reduced frame. Well, all I can say is – walk a mile in the 5D's shoes and we'll see what you really think.

Anyone that shot film with an SLR prior to digital knows how frustrating looking though the smaller and dimmer viewfinders of most 1.5X and 1.6x digital cameras can be. Looking through the viewfinder of a full-frame camera like the 5D, by comparison, is like taking a whiff of pure oxygen. The image will be big, and bright, and yes, did I mention that it's full frame?

Which of course will be the topic de-jour online. Lots of folks will posture about how reduced frame cameras are better because they crop out the soft corners of some lenses. They'll also carry on about how 1.5X and 1.6X cameras give you greater reach with telephoto lenses (ya, right).

But, the reality is that with the exception of a handful of special lenses released over the past year or two that are designed for reduced frame cameras, the millions of lenses out there project a bigger image circle, and being able to use that image circle is a wonderful thing for a great many reasons. True, a high resolution full-frame camera like a 1Ds MKII, or now 5D, will mercilessly expose the true qualities of poorer lenses, but such is life. I don't know a single professional photographer who uses a reduced frame DSLR for any reason other than size and price, or because that's what's available in their preferred camera maker's lens mount. The 5D is going to alter that equation, and the industry is never going to be the same again.

Here's the link:

http://www.luminous-...-announce.shtml

If anyone still objects to me calling the 5D full frame by the way,  I note that as well as everyone else in the known universe using this term, Canon uses it liberally on their 5D page.

http://consumer.usa....=11933&pageno=0

<{POST_SNAPBACK}>

Bob, I don't object to the use of the term full frame for the fine Canon 1Ds and 1Ds mk2 cameras or for the new 5D, thats what they are, full frame. But the Olympus E-1 and E-300 cameras are also full frame. The backs being produced for 645 are very close to full frame, see Wetpixel home page for the one with the X 1.1 lens factor. All I have been saying is that about 3000 readers have come to this thread to learn more about photography and they many want to know the diffrence between what full frame means and what a 35 mm full frame sensor is.

Phil Rudin

[Kasey]

My thoughts on your question are that the new 60 mm is as close as you can get to a 100 mm macro for 35 mm. Nearly the same angle of view and what appears to be life-size for the x 1.6 sensor. The 35 mm, 100 mm macro endsup having the angle of view of a 160 mm film lens and the 50 mm ends up at an 80 mm angle of view and is a 1:2 lens without the extension tube. Can't help but think that a lens designed for the  x 1.6 sensor would also give advanced performance over the older film lenses.

Phil

<{POST_SNAPBACK}>

But why not use the regular mount so it can project onto the 35mm sensor as in the 5D? It seems that canon is saving itself a few bucks and not passing to the consumer - can't think of any other reason...