Originally posted by bossa ...........
My question is:
If you took the same shot with both lenses at those distances the subject should be the same size in the shot although the background would be different. Is there any real difference in the result?
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well...all I know that you should take into the consideration the censor density or the print size also. I don't have any of the 50/1.4 right now (hesitating about the legacy 55/1.4 or sigma 50/1.4) to give you a straight comparison. But many people assume bokeh to be the same as DOF. Extremely thin DOF doesn't exactly mean pleasant bokeh and vise versa. I used to own Olympus 35-100/2.0 and 150/2.0. It's equiv.to 70-200/4.0 and 300/4.0 (focal length and DOF wise), and I can tell for sure that none either of my customers or friends (canon users) could even apriximately guess the DOF eqiuv.on a FF looking at the pictures. But there was no way the pictures were simiar to canon 70-200/4.0. I mean it's all very relative assuming the distortions are corrected if present. There are so many other characteristics besides DOF which affect the look of the background.
As for the Samyang 85/1.4 lense...it can be very soft wide open and give you very dirty colors depending on the lighting conditions - which I dislike. And..can be reasonably sharp at 1.4 and excessively sharp at 2.0 for portraits with good light. It took me sometime to adjust my prosessing accordingly to manage it's character. But any 85/1.4 has something special - it's weaknesses and strong sides. It's just this kind of lense. But it's certainly a must have for portraiture since you have some space behind to step away from the model. 50mm even on a crop doesn't always give you that special look. It makes faces bigger, etc.
I'm not really fond of technical part of the shooting. I mean I have to learn my minimum to get the idea and somewhat predict the result. But I enjoy shooting much more. One of the reasons I left russian forum. Many people are whining there that they need this or that camera or lense to fullfill their needs. And Pentax is the only brand that has to do it... Etc.
So..I dunno if I've answered your question...If not - it's not becuase I didn't want to, but becuase I don't know myself; if yes - well, it's still unintended
Two more files with this lens on K-5 just to compare with the other shot:
http://www.filedropper.com/ost0920 - f 1.4
http://www.filedropper.com/ost0938 - f 2.0