Micro 4/3rds vs. Full Frame

photojoe55 wrote:

Am I correct that in Macro work, the main advantage of Full Frame is due to the sensor size, (1:1 = 1:1 and it is simply quite a bit larger)

I wouldn't say "advantage". Depends on what you want to achieve, because the designation "1:1" is tied to sensor size. An object 36 mm wide fills a full frame sensor at 1:1, an object 18 mm wide a m4/3 sensor also at 1:1. If both sensors have the same pixel count and resolution is not diffraction or lens limited, magnification of similar sized prints will be greater with the smaller sensor.

and a main advantage of a smaller sensor like micro 4/3rds is an increased Depth of Field? If that is correct, would an even smaller sensor like in the FZ300 produce an even greater Depth of Field?

It's not that simple, because you have to factor in diffraction. It's true that you get more DOF at the same f-stop with smaller sensors, but diffraction sets in earlier too. In macro work you get to diffraction limiting apertures very soon, especially with smaller sensors. In the end looking at similar sized prints of pictures taken at diffraction limited resolution, sensor size doesn't make a difference - all prints will have the same DOF.

Thank you in advance, …Joe

Hope this helps!

Phil

philzucker wrote:

I wouldn't say "advantage". Depends on what you want to achieve, because the designation "1:1" is tied to sensor size.

Hope this helps!

Phil

I'm sorry I have to contradict you, but the "1: 1" designation is independent of the sensor size, as well as any other magnification ratio.

3D Gunner wrote:

philzucker wrote:

I wouldn't say "advantage". Depends on what you want to achieve, because the designation "1:1" is tied to sensor size.

Hope this helps!

Phil

I'm sorry I have to contradict you, but the "1: 1" designation is independent of the sensor size, as well as any other magnification ratio.

Technically you are of course correct. I was referring to the OP's statement that a larger sensor is is better in Macro - because 1:1=1:1. I wanted to illustrate that 1:1 actually means different things on different sensor sizes as far as field of view is concerned. Olympus/OM actually uses FF equivalents for magnification in their lens descriptions to emphasize that fact. Hope that clears that up!

Phil

photojoe55 wrote:

Am I correct that in Macro work, the main advantage of Full Frame is due to the sensor size, (1:1 = 1:1 and it is simply quite a bit larger) and a main advantage of a smaller sensor like micro 4/3rds is an increased Depth of Field? If that is correct, would an even smaller sensor like in the FZ300 produce an even greater Depth of Field?

I have a particular interest in this, having used the FZ300 a lot for photographing insects etc and now using full frame instead. I'm afraid this got rather long and detailed. Please feel free to ignore.

An MFT camera will give greater depth of field than a full frame camera for a given f-number, let's say f/8. A 1/2.3" sensor camera like the FZ300 will give even greater depth of field at f/8.

However, for a given scene you can get greater depth of field with a full frame camera or an MFT camera than with an FZ300

I know, this doesn't sound right. However ....

The FZ300 is a fixed lens camera. Like many small sensor cameras it has a macro mode. This lets you focus down to a scene width of around 40mm, with a working distance between the lens and the subject of 10mm. This short working distance and relative large minimum scene size is not suitable for a lot of small scenes, especially when it comes to insects and other invertebrates. That means that the only practical approach with a camera like the FZ300 for shots like the two below is to use close-up lenses.

This one used a Raynox 150 close-up lens and would have had a working distance of around 200mm.

This red mite is rather smaller, with the body around 1mm long, and it would have used a more powerful close-up lens setup, possibly a Raynox 250, in which case the working distance would have been around 120mm, or possibly something stronger, in which case the working distance would have been shorter.

You will see that both of these used f/8, which is the minimum aperture for the FZ300, which gives the maximum depth of field which can be achieved with the camera and others like it.

With a full frame camera using a macro lens, the minimum aperture is likely to be f/22. (It is f/16 for some macro lenses and f/32 for some others, but for now let's assume that it is f/22. And let's also assume that it isn't a Nikon setup, which works a bit differently.)

With the lens set to f/22, we call f/22 the "nominal f-number". However, the actual f-number you are using, known as the "effective f-number", is different. It can be calculated approximately using the following formula. (There is a more complicated and more accurate formula, but it includes a term which generally isn't known for a particular lens, so this is the simplification that is generally used.)

Effective f-number = Nominal f-number * ( 1 + magnification )

So for example if you set the lens to f/22 and shoot at 0.5X magnification (1:2) the effective f-number is approximately

f / 22 * ( 1 + 0.5 ) = around f/32

If you set the lens to f/22 and shoot at 1:1 the effective f-number is approximately

f / ( 22 * ( 1 + 1 ) = around f/45

If you set the lens to f/22 and shoot at 2X (2:1) the effective f-number is approximately

f / ( 22 * ( 1 + 2 ) = around f/64

So as the magnification goes up, the effective f-number gets larger and the effective aperture gets smaller. With a smaller effective aperture, depth of field increases (and so does the amount of detail lost from diffraction softening).

However, when using close-up lenses the effective f-number does not change as the magnification changes. That means that if you shoot with minimum aperture of f/8 with an FZ300 for example then you are using f/8 whatever the magnification. Because of the difference in sensor sizes, f/8 on a 1/2.3" camera like the FZ300 gives around the same depth of field as f/45 on full frame. And this gives the maximum depth of field which is possible with the FZ300.

However, with a full frame camera you can push the effective aperture beyond f/45 if you increase the magnification enough. So with your macro lens at f/22, at any magnification greater than 1:1 you will get greater depth of field than you can with the FZ300. If you are using a macro lens that only goes to f/16, like the Canon MPE-65, then you have to get to 2:1 before you can match the depth of field from the FZ300 at f/8. However, beyond that (and the MPE-65 goes out to 5X magnification) you can get greater depth of field than with the FZ300.

This is why, after using close-up lenses for over a decade, most often on cameras like the FZ300 and its FZ200 predecessor and earlier the similar Canon SX10is, I switched to using a full frame camera, so I could get greater depth of field and achieve results I couldn't with my small sensor bridge cameras.

With full frame I now work routinely with f/11 set on the lens and a pair of 2X teleconverters, which combine to give a nominal f-number of f/45 (f/(11*2*2). When I set 1.5X magnification on the lens, this gives 6X overall magnification with the two teleconverters (1.5X * 2 * 2) and that is around what I use for subjects like this, with an effective f-number of around f/112 (45*(1+1.5)).

The most extreme example I have is this one, which used f/22 on the lens to give a nominal f/number of f/90 (22*2*2) and 2X magnification set on the lens for total magnification of 8X (2 * 2 * 2) and an effective f-number of around f/270 (90 * ( 1+2)).

Bear in mind though, that there is a cost that comes with these greater depths of field, and that is greater loss of fine detail from diffraction softening. I use post processing to try to make something usable from the very soft images I get when using very small apertures.

I could get even greater depth of field with MFT by using the same lens and teleconverter setup on MFT, However with the full frame I have already reached the limit of what I can handle in post processing by way of diffraction-softening from small apertures, and so although I could get greater depth of field using the same lens and teleconverter setup on MFT the images would be too soft and lacking in detail for me to make use of.

Thank you in advance, …Joe

photojoe55 wrote:

Am I correct that in Macro work, the main advantage of Full Frame is due to the sensor size, (1:1 = 1:1 and it is simply quite a bit larger) and a main advantage of a smaller sensor like micro 4/3rds is an increased Depth of Field? If that is correct, would an even smaller sensor like in the FZ300 produce an even greater Depth of Field? Thank you in advance, …Joe

I think the main difference between m4/3 and FF, aside from image size, is that at wide apertures, you get more dof, but as you stop down, the diffraction at f/11 is similar to f/22 with full frame, so it ends up basically the same.

Trying to get shallow dof with the m4/3 gives the impression it has more dof, but it's really the range is just narrower. My f/2.8 is f/5.6 in FF. I can't go wider like they can. If there is any real gain, it's shutter speed. I can manage faster shutter speeds at the wider apertures.

I think it's very comparable to landscape where you need narrow apertures, but also shutter speed to avoid camera shake hand-held. I take advantage of not stopping down as far.

BBbuilder467 wrote:

[...] If there is any real gain, it's shutter speed. I can manage faster shutter speeds at the wider apertures.

Indeed a real bonus for smaller sensors. Thanks for pointing that out!

Phil

It's common to say that small sensors have greater DOF.  That's usually so, but to be precise, the sensor size is not the reason.  The greater DOF comes from the shorter focal length lens.

For macro work, you can convert focal length and distance (from camera to subject) into magnification.

DOF = k * f# (1 + M) / M^2       M=Magnification

f# is the number you set on the lens.  The (1+M) term corrects for the effective f number.  So for example at 1x, the effective f number doubles and (1+1) = 2, which corrects for this.

k depends on how much blur you tolerate, but k=.02 is pretty reasonable when DOF = millimeters.

This formula is correct regardless of sensor size or lens focal length.  But small sensors allow lower magnification because the pixel spacing is smaller.  And lower magnification  results in greater DOF.

Alan

c h u n k wrote:

3D Gunner wrote:

philzucker wrote:

I wouldn't say "advantage". Depends on what you want to achieve, because the designation "1:1" is tied to sensor size.

Hope this helps!

Phil

I'm sorry I have to contradict you, but the "1: 1" designation is independent of the sensor size, as well as any other magnification ratio.

He was right in what he said. He meant 1x was tied to sensor in terms of the relative fov. Was pretty clear he also understands that a lenses magnification is independent, but the resulting image is not.

The FF format has nothing special in it other than the fact that it was mostly used before digital photography. It is referenced only by the fact that most connoisseurs quickly get a rough impression of what an image looks like if a certain lens with a certain focal length is used.

That's all, nothing more.

The final image has nothing to do with the FF format. Absolutely no one can deduce with certainty the size of the sensor with which an image was made (without some specific info), for any image, at any magnification ratio.🙂

c h u n k wrote:

3D Gunner wrote:

c h u n k wrote:

3D Gunner wrote:

philzucker wrote:

I wouldn't say "advantage". Depends on what you want to achieve, because the designation "1:1" is tied to sensor size.

Hope this helps!

Phil

I'm sorry I have to contradict you, but the "1: 1" designation is independent of the sensor size, as well as any other magnification ratio.

He was right in what he said. He meant 1x was tied to sensor in terms of the relative fov. Was pretty clear he also understands that a lenses magnification is independent, but the resulting image is not.

The FF format has nothing special in it other than the fact that it was mostly used before digital photography.

lol. I think you are underestimating the understanding other people may have. etc.

but grab up a 100mm macro lens which maxes at 1x magnification. Set it to max magnification on your full frame. Take a picture of a ruler....Now, Do the same thing with an apsc. Not the same.

So what?

Magnification is the ratio between an object’s size when projected on a camera sensor versus its size in the real world. That's it, nothing more, nothing less, and this in independent of the sensor size, by definition.

In the 1:1 magnification ratio, content with the same size as the sensor (in the focus plane) is reproduced on the surface of the sensor, regardless of the size of the sensor: 24 x 36mm in the case of FF, 17.3mm x 13mm in the case of m4 / 3 system, and so on...

This is true for any format, from the smallest sensors on phones or all sorts of miniaturized devices, to the largest formats available. FF is just one of them, it has nothing special about it.

So, in principle, smaller subjects are easier to be reproduced on smaller sensors.

And in the end, only the magnification level reported between the size of the subject and the display device is significant, which is not related to the size of the information capture medium.

As for your last starment. Lets say the display device is the same 27" imace. You take a photo of a mite at 2x magnification with the same lens and...well, okay, equivalent apertures between a ff and an apsc. Display both on the 27" imac, uncropped. Nope. Still not the same image.

It is obvious that it is not the same image because the content captured on the sensor differs.
Also, the final magnification level is higher for the pursued subject captured with the APS-C sensor on the same 27 "screen.

You can also shoot the same subject with an MF camera, with the same optical system that offers a 2:1 magnification and it is obvious that the content of the image will not be the same.

Who says that what captures a 24x36mm sensor is a reference? Why not reference a sensor with a size of 30x47mm, or one with a size of 20x32mm, or any other size?

The projection of an object (or part of it) will have exactly the same size on any sensor, of any size, in the case of the same magnification ratio. Absolutely nothing in this regard is tied to the FF format.

..............................................

For example, a spherical object with a diameter of 1mm, in the case of a magnification ratio of 1:1 will be represented on any sensor, of any size, by a circle with a diameter of 1mm.

The difference in image content between sensors of different sizes is what is reproduced around the pursued subject (for same magnification). If the spherical object (1mm diameter) is photographed on a black background, we will have more or less useless black background around the spherical object.

If we photograph the respective spherical object with a small sensor for phones, with a high pixel density, with quality processing algorithms and an optical system suitable for the 1:1 magnification ratio, the spherical object taken for example will be able to be observed with many details on it (assuming that there are those details), on a decent size black background, unlike what is captured on the 24x36mm FF sensor, respectively a tiny 1mm object surrounded by an unnecessarily very large black surface.