NorBro
Major Contributor
One last thing to mention is that the SP at 1.2 might be as sharp as the DS at 1.8 or 2. So, if you'd rather not open the DS past 2, we might be talking about a bigger effective brightness difference. Just thinking about options. Whether or not it's worth it would depend on its actual transmission and its cost.
They don't have the Rokinon DS 50 in this database, but here's a tool showing how much sharper the SP 50 is at 1.2 than the much more expensive Canon L 50 1.2:
https://www.the-digital-picture.com...meraComp=979&SampleComp=0&FLIComp=0&APIComp=0
Canon's 50mm f/1.2 is from a different world in 2007 (part of what I mentioned the other day about lenses improving).
A lot of the high end glass from back then is now noticeably softer when compared to newer, cheaper options.
I used to use that same tool and obsess and waste money constantly for years. Not saying it would be a waste for you, but it was for me because it was unnecessary, wasn't as useful or practical the way I imagined it, and no one would ever notice a difference, quite frankly.