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**Klaus** · 08-22-2016, 11:15 PM

So I'm torturing you ONCE more ;-)

http://www.opticallimits.com/Reviews/986-equivalence

dave9t5 · 08-23-2016, 01:02 AM

Thank you.

Think this should be "50mm f/2.8" ?

Micro-Four-Thirds

Leica DG Summilux 25mm 1.4

"50mm f/2"

**Klaus** · 08-23-2016, 02:16 AM

Right. See .. even I got confused ;-)

borisbg · 08-23-2016, 06:12 AM

Klaus, thank you for taking the time to write it... you could have gone to take pictures instead.

I am sure some of the PZ members will pull the calculators out (like revolvers in western).

stoppingdown · 08-23-2016, 07:03 AM

It's a topic in which I don't feel sure... ever. But for what I read, no revolver at my side. Smile

**Klaus** · (This post was last modified: 08-23-2016, 07:06 AM by Klaus.)

Sure, seeing is believing. I will add some pictures later on maybe.

**Klaus** · 08-23-2016, 07:24 AM

Quote:It's a topic in which I don't feel sure... ever. But for what I read, no revolver at my side.

Math is on my side. Thus my ammunition is fairly powerful ;-)

However, PERSONALLY I don't care too much about this topic. I have made my peace with small format systems long ago.

When carrying beasts such as a Canon EF 11-24mm f/4 USM L or Sigma 150-600mm Sports for an hour, I just know that this just isn't the place to be for me. It's fun for that single hour but then it's enough really.

obican · 08-23-2016, 07:31 AM

Now let's carve all what you've written into a wooden club and bash people repeatedly with it everytime they say oh FF is much better Fuji is only APS-C Hasselblad will be great because it's medium format.

Jokes Image noise aside (I wasn't even joking btw), do we have evidence that with larger photosites, does a better dynamic range and color information come too? Even though the lenses are slower? I will not take DXO as evidence btw so please nobody post links (A wooden club has multiple uses, mind you).

stoppingdown · 08-23-2016, 08:09 AM

Quote:Math is on my side. Thus my ammunition is fairly powerful ;-)

True, but this topic manages in generating confused discussions in spite of that. Rolleyes

I think that the problem isn't math and how it's understood, but the lack of clarity, in some discussions, about all the factors that play a role - mostly the fact that to achieve the same framing you have to either change the focal length or the focal distance.

Quote:However, PERSONALLY I don't care too much about this topic. I have made my peace with small format systems long ago.

When carrying beasts such as a Canon EF 11-24mm f/4 USM L or Sigma 150-600mm Sports for an hour, I just know that this just isn't the place to be for me. It's fun for that single hour but then it's enough really.

With the partial exception of the 150-600mm ©, which anyway is a pain to carry on (yesterday I tried it with a 7km hike for the first time...), I agree. Nevertheless the argument is important because you're aware of the trade-off and you accept it. And since it's not only a matter of FF vs APS-C, since we are also offered with smaller sensors, knowing the thing makes one to precisely pick the trade-off which is fine for him. For instance, I accept the loss of DoF with APS-C, but not going further in that direction.

Brightcolours · (This post was last modified: 08-23-2016, 09:12 AM by Brightcolours.)

A few notes:

Sensor sizes vary. Especially Nikon sensor sizes can go from close to 1.5x crop factor to 1.56x crop factor, but you state one specific size. No biggie, but could be more accurate.
With MFT's 2x crop factor is derived from the diagonal. 17.3mm width and 13mm height give a 21.64mm diagonal. FF has a 36mm width, 24mm height, giving it a 43.67mm diagonal, which gives it a very near 2x (1.9993) crop factor. You could define the crop factor by looking at the horizontal FOV, which would then be 2.08x. Or the vertical FOV: 1.846x. Or you could crop the 4:3 to 3:2, then you end up with the same diagonal FOV and crop factor as the horizontal one: 2.08x. I am unclear what you derive that 1.92x from? Maybe I made a mistake?
FF actually has more like a 1 1/3rd stop advantage over APS-C, to keep things "right". ( 1.6 x f2 = f3,2, 1.5 x f2 = f3. 1 stop would be f2.8)
To get a more appropriate APS-C example, use an FF lens . Canon EF 70-200mm f4 L or Nikkor 70-200mm f4 VR. Yeah, I know that is wonky image circle wise, but truth is that with these longer lenses aperture starts to dominate the optics size (and the wonkiness is to APS-C's disadvantage anyway, so who cares). The weight of the 2 Canon 70-200mm f4 lenses is 705/760 grams.