canon 85mm f1.8

I have just stuck some figures into a depth of field calculator.

At a distance of 10ft (for head and shoulder portrait) you get the following depth of field f1.8 = 0.28 ft. and f1.2 = 0.19 ft. on a canon crop sensor.

On a Canon full frame the figures are f1.8 = 0.29 ft.. and f1.2 = 0.44 ft. So the differences in depth of field are 0.07 ft. for crop sensor or 0.15 ft. for full frame
 
the f1.8 is good but the f1.2 is better - the price says it all.

the images you get from the f1.2 are very sharp.
 
I have just stuck some figures into a depth of field calculator.

At a distance of 10ft (for head and shoulder portrait) you get the following depth of field f1.8 = 0.28 ft. and f1.2 = 0.19 ft. on a canon crop sensor.

On a Canon full frame the figures are f1.8 = 0.29 ft.. and f1.2 = 0.44 ft. So the differences in depth of field are 0.07 ft. for crop sensor or 0.15 ft. for full frame

As I said earlier, not much in it :)
 
the f1.8 is good but the f1.2 is better - the price says it all.

the images you get from the f1.2 are very sharp.
Those two things you said, we knew that.

(But - the images you get from the f/1.8 are very sharp also)
 
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Are you serious with this comment?

The 3D-ness comes from contrast/micro-contrast, sharpness of fine lines. Which IMO makes the in focus areas stand out more than in a lens without good contrast
Hence exaggerating the difference between in focus and out of focus,

something like the 50mm 1.4 is so soft wide open that I feel you get more of a difference between sharp and blurred at f2 than you do at 1.4, so three dimensionality is just sharpness and contrast

This is a real thing based in physics and optics, not a mythical concept
 
The 3D-ness comes from contrast/micro-contrast, sharpness of fine lines. Which IMO makes the in focus areas stand out more than in a lens without good contrast
Hence exaggerating the difference between in focus and out of focus,

something like the 50mm 1.4 is so soft wide open that I feel you get more of a difference between sharp and blurred at f2 than you do at 1.4, so three dimensionality is just sharpness and contrast

This is a real thing based in physics and optics, not a mythical concept
A sharp lens with shallow DOF then?

A real thing based on physics?? Lol! The flat photo it produces are still very much in two dimensions :)

FWIW the f/1.8 is very sharp wide open, and with a DOF deference of only a few CM there really isn't anything in the DOF. It's definitely no more 3D than the f/1.8 ;)
 
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Forums are amazing places to obtain the necessary info to improve our *art*. Now that I've learned the dof range between the two lenses I know now that maths trumps *everything*.

My 1.8 can now sleep soundly at night knowing the L can't make "magic" happen. It's all lies I tells you. :D
 
Forums are amazing places to obtain the necessary info to improve our *art*. Now that I've learned the dof range between the two lenses I know now that maths trumps *everything*.

My 1.8 can now sleep soundly at night knowing the L can't make "magic" happen. It's all lies I tells you. :D


Does the maths of £237 for the f1.8 v £1299 for the F1.2 enter into the equation?
 
Forums are amazing places to obtain the necessary info to improve our *art*. Now that I've learned the dof range between the two lenses I know now that maths trumps *everything*.

My 1.8 can now sleep soundly at night knowing the L can't make "magic" happen. It's all lies I tells you. :D
I think the point was more along the lines of "is it worth paying £1k extra for a few CMs of shallow DOF" when that was brought up as a bonus point for the L lens :)

There is of course more to the L lens than that.
 
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Does the maths of £237 for the f1.8 v £1299 for the F1.2 enter into the equation?

Does the maths of £237 for the f1.8 v £1299 for the F1.2 enter into the equation?

I'm not sure why you would ask such a question to me. For some yes, for others no. :D

If I had the money laying around that I had to spend on gear then I'd get the L in a heartbeat. But for now the 1.8 satisfies me enough.
 
I think the point was more along the lines of "is it worth paying £1k extra for a few CMs of shallow DOF" when that was brought up as a bonus point for the L lens :)

There is of course more to the L lens than that.

Absolutely yes! :D Others may have a different opinion... That's the beauty of "opinions" - we can all have different ones. :)
 
I'm not sure why you would ask such a question to me. For some yes, for others no. :D

If I had the money laying around that I had to spend on gear then I'd get the L in a heartbeat. But for now the 1.8 satisfies me enough.

I own the 1.2, I've owned the 1.8 and I own the sigma 1.4. There really is something Magic about the canon l primes, the 50 1.2 has it, the 35 1.4 has it, the 85 1.2 has it- I have other lenses in the same focal length that lack the magic of the l lenses, but even though I know the l series is better I would grab the 1.4 because I don't want to carry around 1kg of lens, sometimes practicality wins out over Image quality- sometimes

I did great work with the 85 1.8, maybe even some of my best work to date- but would it be 10% better with the 1.2, probably, is that worth the cost and the size/weight, probably not

I would pick th 85 1.4 as the best bang for the buck though
 
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