SIGMA 85mm f/1.4 ART Best 85 ever?

Talley wrote in post #18284956
1.8 boring

Honestly, the difference between f1.4 and f1.8 is negligible.

CheshireCat wrote in post #18285577
This is a common misconception.

Please explain.

Patbil10 wrote in post #18286553
Please explain.

The visible color spectrum is a continuum of frequencies.
A color sensor only has 3 elements (Bayer matrix) that are sensible to these frequencies, with known sensibilities to each frequency of the spectrum.
A bad lens acts as a filter that attenuates these frequencies with a complex (often unspecified) function, so that some frequencies hitting the sensor are not sampled with the expected "balance", therefore color is reconstructed incorrectly.

The misconception is to be able to magically fix this complex color error function in post by means of white balance and pushing/pulling some color frequencies. The problem is that the original continuum signal has been lost after being filtered by the Bayer matrix, therefore it is hard or impossible to "invert" the bad error function to perfectly reconstruct the original colors.
Yes, you may be able to get near to natural colors, but fixing some colors will produce errors in others, and the results will depend on the scene and the nature of the original light illuminating the scene.

CheshireCat wrote in post #18286649
The visible color spectrum is a continuum of frequencies.
A color sensor only has 3 elements (Bayer matrix) that are sensible to these frequencies, with known sensibilities to each frequency of the spectrum.
A bad lens acts as a filter that attenuates these frequencies with a complex (often unspecified) function, so that some frequencies hitting the sensor are not sampled with the expected "balance", therefore color is reconstructed incorrectly.

The misconception is to be able to magically fix this complex color error function in post by means of white balance and pushing/pulling some color frequencies. The problem is that the original continuum signal has been lost after being filtered by the Bayer matrix, therefore it is hard or impossible to "invert" the bad error function to perfectly reconstruct the original colors.
Yes, you may be able to get near to natural colors, but fixing some colors will produce errors in others, and the results will depend on the scene and the nature of the original light illuminating the scene.

Wow ! Thanks for the highly technical answer...however it's not enough to make me want to move to the Sigma lens. Also the color variations are nearly impossible to see...at least not to me or my clients who are more than happy with the images I deliver with this lens.

Patbil10 wrote in post #18286655
Wow ! Thanks for the highly technical answer...however it's not enough to make me want to move to the Sigma lens. Also the color variations are nearly impossible to see...at least not to me or my clients who are more than happy with the images I deliver with this lens.

Fair enough

Some people are more sensible to colors than others and have different color perception/preference, possibly by nature and certainly by training.

For example, I quite dislike the brownish color cast of many Samyang primes while some people like it.
For best colors, I usually go Zeiss or some high end Canon primes. Good glass comes at a premium cost, and it is understandable that low-cost competitors save on that.

Patbil10 wrote in post #18286549
Honestly, the difference between f1.4 and f1.8 is negligible.

Actually it's not...

it's 1/500 vs 1/2000

You try stopping motion when your riding the limit of ISO and your buried wide open. Don't forget your exposure triangle... could also be the difference of ISO 6400 rather than 10,000.... again makes a difference on noise.

Talley wrote in post #18288718
Actually it's not...

it's 1/500 vs 1/2000

You try stopping motion when your riding the limit of ISO and your buried wide open. Don't forget your exposure triangle... could also be the difference of ISO 6400 rather than 10,000.... again makes a difference on noise.

What? The difference from f/1.4 to f/1.8 is 2/3 stop.

The difference between 1/500 and 1/2000 is two full stops.

So f/1.8 to f/1.4 should be 1/500 to 1/800. Not 1/2000.

JeffreyG wrote in post #18288793
What? The difference from f/1.4 to f/1.8 is 2/3 stop.

The difference between 1/500 and 1/2000 is two full stops.

So f/1.8 to f/1.4 should be 1/500 to 1/800. Not 1/2000.

ya that

this is what i get for working and being on my phone same time durr... massive brain fart

I was referring mostly to depth of field. Don't care so much about the 2 stops of light...our cameras are excellent at high ISO and my 85 is mostly used in situations where the lighting if perfect...