06-14-2016, 11:40 AM
Pana/Leica 12mm f/1.4 coming
06-14-2016, 11:46 AM
Hmm... one more reason/method of getting rid of the Canon 24/1.4 L while retaining a fast lens in this FOV. The Fuji 16/1.4 had me thinking back when it appeared, and now this one...
06-14-2016, 11:57 AM
Will you be testing the fuji 16f1.4 ?
06-14-2016, 12:46 PM
Quote:Will you be testing the fuji 16f1.4 ?yes
06-14-2016, 01:24 PM
Quote:Hmm... one more reason/method of getting rid of the Canon 24/1.4 L while retaining a fast lens in this FOV. The Fuji 16/1.4 had me thinking back when it appeared, and now this one...Still the same error of thinking?
The 12mm f1.4 L will be full frame equivalent to:
12 x 2 = 24mm (not really but kinda, since the aspect ratios are different and the crop factor is diagonal based).
1.4 = f2.8
That is quite a lot slower, and uhmm.. Canon already does offer a 24mm f2.8 IS USM.
If you think the MFT lens is faster than a f2.8 FF equivalent, you have a wrong idea about "speed". Equivalent settings will give similar exposure times.
For MFT to offer the same "speed", they would need to offer a f0.75 lens.
On a side note, was it not you who shot with a 1D mkIV which has an 1.3x crop factor, though?
06-14-2016, 01:54 PM
I agree with Brightcolors here. MFT is not the right place if shallow DoF is the _primary_ objective.
The efforts for producing these high-speed lenses are immense despite a less than exciting outcome (DoF-wise).
MFT remains the first choice when it comes to portability in combination with achievable field-of-view.
That being said I'm pretty much convinced that MFT has a "sufficient" DoF potential for 90% of the amateurs.
06-14-2016, 01:58 PM
Of course, with such lenses many will be happy with the shallow DOF ability on offer, just like many are with f2.8 on FF 135 format or f4/6.6 on MF format.
And speed wise... Light per square mm/cm/m is meaningless in photography. Set the cameras to equivalent ISO settings, and f1.4 on MFT is not the same as f1.4 on FF.
06-14-2016, 01:59 PM
Error of thinking is at you, BC. The equivalent is only DoF, not fast or slow correlating to shutter speed. When I use the 23/1.4 on Fuji and have 1/250, I also have 1/250 with 35/1.4 on FF.
Try instead of talk your theory. Anything else would not be logical, related to sensor sensitivity or refraction index of the used glass.
Aperture is a proportion, no absolute dimension.
Anyway, the Leica looks nice. I just stick with Touit 12/2.8
Quote:Error of thinking is at you, BC. The equivalent is only DoF, not fast or slow correlating to shutter speed. When I use the 23/1.4 on Fuji and have 1/250, I also have 1/250 with 35/1.4 on FF.Not an error at all, it is an error of thinking that somehow you need to use the same ISO setting for each. That is the error of thinking.
Do you have the opinion that somehow the sensor in a Nikon D750 or Canon 6D and a GX5 somehow have "the same sensitivity"?
Now for the simple maths:
24mm / 2 = 12mm.
Same FOV with equivalent focal lengths.
Aperture is a dimension, by the way.
12 / 1.4 = 8.57mm diameter aperture
24 / 2.8 = 8.57mm diameter aperture
Whadoyaknow, the same size the light travels through. Amazing. B)
Same DOF with equivalent F-stops.
ISO 100 on MFT, equivalent ISO setting on FF:
100 x 2 x 2 = ISO 400.
Using that equivalent ISO setting... Whadoyaknow, the same exposure time. How is that for speed.
By the way, stop saying it is "my" theory, though. It is generally accepted stuff, just optics and physics. :ph34r:
06-14-2016, 06:05 PM
Film speed and sensor speed are not the same - but there's a standard for them: https://en.wikipedia.org/wiki/Film_speed see The ISO 12232:2006 standard and Measurements and calculations.
Btw., sensor area doesn't play a role in the formulas, if I'm not mistaken.
Now, instead of talking theoretically I wanted to see if I'm wrong. I set up the same ISO, measuring method and aperture. First was 23/1.4 (APS-C) and 35/1.4 (FF)
Both 1/200 as shutter speed - where is the equivalence? Should be 1/200 Ã— 1.5 = 1/133
Next with f/8: â…›" on both cameras
Next were 35/2 (APS-C) and 50/1.4 (FF), I don't have a 52.5 mm lens
1/40 for APS-C Ã— 1.5 = 1/26â…“ for FF - but FF shows 1/50. Equivalence?
You can remain in your thinking model and I will in mine. I just never saw a proof for your reasoning. Maybe with a better lit test scene than mine.
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