How to differentiate crop vs. FF

[AvTvM]

Re: How to argue crop vs. FF

It's a stop and a third, of noise performance and DOF control (assuming you can keep constant framing through either a change in focal length at the same f-stop or a change in subject distance). You pay for that just like you do with lenses.

exactly.

It is a matter of how much photographic possibilities, capabilities and image quality you need or want and are willing and able to pay for.

Also, while FF cameras and lenses are larger, heavier and more expensive than APS-C gear, the relation is certainly not proportional to sensor size. In real life, FF with more than 200% of Canon APS-C imaging area comes with a 0% [e.g. Sony A7/R, and all tele lenses>135 mm] to max. 50% size, weight, price "penalty".
mFT and 1" sensored gear scales even less proportionately against FF in terms of capabilities, size, weight and cost.

 

[rs]

It's a stop and a third, of noise performance and DOF control (assuming you can keep constant framing through either a change in focal length at the same f-stop or a change in subject distance). You pay for that just like you do with lenses.

exactly.

It is a matter of how much photographic possibilities, capabilities and image quality you need or want and are willing and able to pay for.

Also, while FF cameras and lenses are larger, heavier and more expensive than APS-C gear, the relation is certainly not proportional to sensor size. In real life, FF with more than 200% of Canon APS-C imaging area comes with a 0% [e.g. Sony A7/R, and all tele lenses>135 mm] to max. 50% size, weight, price "penalty".
mFT and 1" sensored gear scales even less proportionately against FF in terms of capabilities, size, weight and cost.

Have you seen the size/weight of the Pentax Q?

 

[Loswr]

Have you seen the "ZUIKO DIGITAL ED 300mm F2.8"? In FF equivalent it is a 600 f/2.8 ...

600/5.6. You don't get something for nothing.

It's always both amusing and rather sad that people don't understand the word "equivalent".

 

[iron-t]

I started on "serious" digital cameras with MFT with its 2x crop factor. Performance in low light and DOF were worlds ahead of the compact cameras I had used before. There was absolutely no comparison in terms of image quality, visible even in small prints.

Then I moved to APS-C (Canon natch). It was not as big of a jump in IQ, but it was noticeable to me and others. This was when all the local Walgreens photo print counters started to make me fill out affidavits saying these were my photos--that I was not stealing them from a pro. (I know Walgreens prints are not the best but they are cheap and convenient--these are mostly non-critical prints for distribution to family.)

Then I moved to full frame. Again, not as big of an IQ jump. But you'll like your images better--especially where shallow DOF is desirable, as this is a readily noticeable difference between crop and FF--and you'll be better prepared in difficult conditions such as low light, contra light, etc.

To me the right balance of size/weight/IQ/convenience is: (1) 5D3 whenever and wherever it will be welcome; and (2) EOS-M where discretion or a casual vibe is more important than max IQ.

 

[rs]

the Zuiko is as fast as a 2.8.

You are correct, it is f2.8. And by that exact same premise, the Zuiko is 300mm long too.

What I'd like to know is, if small sensors lead to smaller, lighter systems, how come this lens designed for only a quarter of the frame size manages to weigh in at close on 50% more than the Canon 300/2.8? Even with a 2x TC and bigger body, there's a massive weight saving for the large sensor system, not to mention better handling.

 

[privatebydesign]

Crop sensors don't require all that glass.

In principle you are right if you leave the DOF point away, but I have to correct you in some terms.

Have you seen the "ZUIKO DIGITAL ED 300mm F2.8"? In FF equivalent it is a 600 f/2.8

That's wrong as you do not take the size of the sensor into account.
If you want to gather similar amount of light and want to achive the same DOF on FF
a 600mm f/5.6 would be the equivalent.

To make a better comparison:
Take the EF 70–200 mm 1:2,8L IS II USM
If you want to have the same DOF on FT you would not need a 35-100 1:2,8
but the ZUIKO DIGITAL ED 35‑100mm 1:2.0
If you compare those two, the Canon is lighter, cheaper and even smaller.
Of course, you can take at MFT the new M.ZUIKO DIGITAL ED 40‑150mm 1:2.8 PRO.
This will be lighter, smaller and cheaper than the 70-200 but for the tradeoff of DOF and absolute light gathering on the same area (!) of the sensor.

And don't start with the "equivalent aperture", that's only for bokeh, the Zuiko is as fast as a 2.8.
...
Now, I know that a lot of FF fanatics ...

Of course f2.8 is physically always f2.8 but your comparison here is wrong.
And of course you can take wonderful pictures with MFT.
And I am not a FF fanatic. Indeed and I am very interested in Olympus MFT system (as you probably can imagine by my knowledge about the lenses).
But your argument is physically only correct when you agree in the tradeoff of losing shallow DOF and absolute light gathering.
This you can only compensate by using lenses with bigger apertures and therefore losing the size/weight/price advantage.

No, MFT is a two times crop, you don't lose one stop of aperture you lose two stops (inverse square law, the sensor area is 1/4 the size).

If you want the same DOF you need a 35-100 f1.4 on a MFT compared to a FF 70-200 f2.8.

Nothing touches the 135 format for selective DOF control if that is important to you, further, iso takes a two stop crop factor hit when talking equivalence too.



100mm, f/1.4, 1/200, ISO 100, on a mFT (4/3) camera,

Gets an equivalent shot on a FF camera as

200mm, f/2.8, 1/200, ISO 400

 

[Maximilian]

No, MFT is a two times crop, you don't lose one stop of aperture you lose two stops (inverse square law, the sensor area is 1/4 the size).

If you want the same DOF you need a 35-100 f1.4 on a MFT compared to a FF 70-200 f2.8.

You're right! :-[
Thanks for correcting me. (Damn! I did it right at the 600 mm and then screwed it up)
Makes it even worse for the MFT system. :-X

 

[privatebydesign]

No, MFT is a two times crop, you don't lose one stop of aperture you lose two stops (inverse square law, the sensor area is 1/4 the size).

If you want the same DOF you need a 35-100 f1.4 on a MFT compared to a FF 70-200 f2.8.

You're right! :-[
Thanks for correcting me. (Damn! I did it right at the 600 mm and then screwed it up)
Makes it even worse for the MFT system. :-X

True, and it makes that ZUIKO DIGITAL ED 35‑100mm 1:2.0 at $2,299 a FF equivalent of the 70-200 f4 at a much more modest $1,299. Why do people keep saying crop camera lenses are much better value! Compare for exactly the same photo and they are often not.

Neuro and I have often used the example of the 24-105 f4 IS on FF vs the 17-55 f2.8 IS on APS-C, they are very close equivalents in IQ as well as focal length and apertures, and the FF lens can be had for a few hundred dollars less.

 

[raptor3x]

To make a better comparison:
Take the EF 70–200 mm 1:2,8L IS II USM
If you want to have the same DOF on FT you would not need a 35-100 1:2,8
but the ZUIKO DIGITAL ED 35‑100mm 1:2.0

You'd actually need a 35-100mm f/1.4. The 35-100mm F/2.0 is equivalent to the 70-200 f/4.

 

[Lee Jay]

Have you seen the "ZUIKO DIGITAL ED 300mm F2.8"? In FF equivalent it is a 600 f/2.8 ...

600/5.6. You don't get something for nothing.

It's always both amusing and rather sad that people don't understand the word "equivalent".

It's very odd, especially when the same people don't make the same mistake with teleconverters, which do exactly the same thing as smaller sensors (crop and enlarge).

 

[jarrodeu]

For canon, exposure for a 400mm 5.6 on a crop (640mm 5.6) is the SAME exposure as a 400mm 5.6 on a full frame. By using a crop sensor the aperture doesn't magically shrink. Just like taking the center section of a full frame image to give the same view as a crop sensor does not shrink the aperture.

Jarrod

 

[Loswr]

For canon, exposure for a 400mm 5.6 on a crop (640mm 5.6) is the SAME exposure as a 400mm 5.6 on a full frame. By using a crop sensor the aperture doesn't magically shrink. Just like taking the center section of a full frame image to give the same view as a crop sensor does not shrink the aperture.

Yes, we know. But that doesn't make the resulting images equivalent. If you think it does, you may be trapped within the circle of confusion...

 

[Sporgon]

For canon, exposure for a 400mm 5.6 on a crop (640mm 5.6) is the SAME exposure as a 400mm 5.6 on a full frame. By using a crop sensor the aperture doesn't magically shrink. Just like taking the center section of a full frame image to give the same view as a crop sensor does not shrink the aperture.

Jarrod

That is because correct photographic exposure is dictated by the intensity of light, not volume. So you are of course right that the exposure for a given f stop lens will be ( more or less depending upon the efficiency of the lens) the same irrespective of sensor size or image circle, but when you begin talking about Achieving the same result on different formats you must deal with equivalence in all areas if you want to be correct - not just the 400 to 640 bit

 

[jarrodeu]

For canon, exposure for a 400mm 5.6 on a crop (640mm 5.6) is the SAME exposure as a 400mm 5.6 on a full frame. By using a crop sensor the aperture doesn't magically shrink. Just like taking the center section of a full frame image to give the same view as a crop sensor does not shrink the aperture.

Yes, we know. But that doesn't make the resulting images equivalent. If you think it does, you may be trapped within the circle of confusion...

I must have misread. I was under the impression that some people were arguing that 2.8 lens let in the light of an f8 when on the micro 4/3 mount.
Jarrod

 

[Loswr]

I must have misread. I was under the impression that some people were arguing that 2.8 lens let in the light of an f8 when on the micro 4/3 mount.

Only two stops different (f/2.8 vs. f/5.6), not three (f/8). But it's worth noting (again, it was mentioned earlier) that even though exposure is the same since it's based on light per unit area, total image noise is proportional to total light gathered, so with the smaller 2x crop sensor, you're not only gaining two stops worth of DoF, you're gaining two stops worth of noise. Or, if you prefer, you can stop down the FF sensor to match DoF, and if you don't need to maintain the same shutter speed you have less noise, while if you do need to maintain shutter speed you boost ISO and you're no worse off with the FF sensor. So...the smaller sensor gives you the ability to choose shallower DoF and/or lower noise if you want, or produce an equivalent image if desired.

 

[rs]

I must have misread. I was under the impression that some people were arguing that 2.8 lens let in the light of an f8 when on the micro 4/3 mount.
Jarrod

As Neuro said, two stops (f5.6), not three.

To understand this, you need to understand the difference between total amount of light, and the intensity of light. Think of a shaft of sunlight - use a magnifying glass to concentrate that light into a smaller area - you get no more light, but the intensity is increased. Just shrouding more of the light to make a narrower shaft leaves the intensity the same, and reduces the total amount.

A greater intensity of light is what's needed to make a smaller area receive the same amount of light. Simply cutting/cropping out some light, and then magnifying/enlarging what's left afterwards results in less light captured. That's otherwise known as a lower signal, which requires more amplification/enlargement, typically resulting in more noise.

 

[anthonyd]

I stand corrected, I misused the term "equivalent", partly because I was not thinking, partly because I was trying to make a point about focal lengths more than apertures (I know, I know I was being loud about the aperture too, don't shoot).

Sure, if you are doing portraits, where DoF matters, you'll go with FF. The same holds with low light where you want to minimize noise. However, if I were going to visit Alaska or Yellowstone, I think I'd buy a MFT camera and the Zuiko 300/2.8 lens rather than the 600/5.6 for my Canon. The combo will be cheaper, lighter, smaller and unless I'm shooting at dusk or dawn, the grizzlies will show the same size (and probably comparable IQ) on the same size print, or my screen.

Now, on my second complaint about Canon making good EF-S lenses. Yes, they do make some really good ones and some decent ones. However, there is a large range of lenses that they only make in EF. In particular the very long ones. Why should I buy a trash can sized lens if I want the reach of 800mm or more? How hard is it for Canon to make a 500mm EF-S L that weighs less, costs less and is smaller than their EF 800mm L?
Also, their 70-200 is phenomenal, and I'm very glad to own one. However, I use a crop sensor, so a lot of the glass in it goes wasted, and no, the 55-250/4.5-5.6 is not comparable.

 

[anthonyd]

I must have misread. I was under the impression that some people were arguing that 2.8 lens let in the light of an f8 when on the micro 4/3 mount.
Jarrod

As Neuro said, two stops (f5.6), not three.

To understand this, you need to understand the difference between total amount of light, and the intensity of light. Think of a shaft of sunlight - use a magnifying glass to concentrate that light into a smaller area - you get no more light, but the intensity is increased. Just shrouding more of the light to make a narrower shaft leaves the intensity the same, and reduces the total amount.

A greater intensity of light is what's needed to make a smaller area receive the same amount of light. Simply cutting/cropping out some light, and then magnifying/enlarging what's left afterwards results in less light captured. That's otherwise known as a lower signal, which requires more amplification/enlargement, typically resulting in more noise.

rs, you might be right about light, but you are at 666 posts, so you got to post again to avoid being evil

 

[3kramd5]

The combo will be cheaper, lighter, smaller and unless I'm shooting at dusk or dawn, the grizzlies will show the same size (and probably comparable IQ) on the same size print, or my screen.

Time of day changes magnification?

Why should I buy a trash can sized lens

...

I want the reach of 800mm or more

That's why

 

[ashmadux]

Crop vs. Full frame.

As a 6d owner - my first full frame- im very unimpressed at its low iso quality. There is no 3d-ish POP that i have seen in so many 5d2/5d3 images over the years - image quality that i could easily see was not reproducible on my crop cameras.

To these ultra pixel peeping eyes, the 6d is only slightly better at dynamic range than my t2i. High Iso handling is generally FANTASTIC, which is why i figure the low iso takes an image quality hit. Low light photography is a whole other ball game compared to my crop bodies.

So while i enjoy my 6d, its nowhere close to the full frame experience i thought it would be. Still dreaming of a 5d3 and non-ancient AF.



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