Originally posted by doudou54300 Hello everybody...
I hope that i am posting in good thread : i recently bought pentax smc M 50mm f1,4. I use it on my K5 : M mode, with Manual focus selected -
Up to now i used it only in inside condition, at f1,4 and f2. Unfortunately almost all my photos are not clear : when i take photo, focus seems to be perfectly clear on face of subject for example (my eyes see a perfectly clear scene with focus on people face for example) but when i watch photos on computer, almost all are blurr with face not clear. Usually subject is situated at about 1 meter from me.
Is it possible that lens suffer from trouble ? Or just consequence of very small DOF with 50mm f2 ? Can we speak of front / back focus with manual lens or maybe i use this lens in bad conditions ?
Could people in this forum explain me how they manage this 50mm f1,4 lens ?
Thanks in advance !!
Lionel
Pentax K5 + samyang 14mm + DA ltd 40mm + DA ltd 70mm + pentax M 50mm f1,4 + pentax 100-300(4,7-5,6) + sigma 18-35 f1,8
Having shot a lot with the 50 1.4 M on a K 20d, I'd say back or front focusing issues are possible. It happens when you are really close to a subject, focusing a nose tips or something hovering and hanging out in space like the ubiquitous edges of flowers. DOF is very shallow of course making things a bit hard, so that can certainly trip you up. Maybe two other things should be considered though-just for FUN. I'll take the risk of thinking out loud for a moment.
I realized that for a long while when I was first trying out MF Pentax Tak lenses, I had not accepted or was not aware of the sharpness inherent in fast 50s wide open because of all of the talk about softness at 1.4 etc...my subconscious bought into all of that parroting around the net...but Asahiflex cured me of that illusion. So, once I understood the problem was with me, I started practicing and realized that you must use the eye...forget allowing the focus screen to do the job (of course this assumes that the diopter is adjusted correctly and that camera and screen will be aiding you in getting in the ball park quickly). I've never had particularily good eyes and I'm a bit older now, nearly sixty. Still, I have learned to rely on my eye to recognize when something is sharp and ready to shoot, never mind aural dings and blinking lights and such things. The eye will get the needed degree of perfection. It just takes practice and faith that the eye is capable of doing the job. So, the number of sharp shots has gotten much higher for me...but again, you first have to assume the lens is sharp wide open, otherwise you won't put forth a hardy and consistent effort! The second thing-on occasion I forget that there is such a thing as minimum focusing distance...Lord have mercy! It mostly does not happen with the M 50 since it focuses down to about 17 inches or so, I believe. But, nevertheless, it has happened on occasion. So, just maybe you could be getting somewhat closer with the 50 than a meter and just don't realize it. I have an old Tak 300 with a miserable focusing distance-monstrously long-and have shot whole sequences of potentially glorious shots with that lens that later baffled and disappointed me over
slight and unexpected blurriness. I knew that the lens was incredibly sharp the last time I used it! Ha! Lens scolding time...bad lens, bad lens. Later, somehow, the light went on and now I feel lucky to have kept the lens and laugh at my slim wits and lack of memory that accompany picture after picture some days. You can be shooting just barely barely past the edge of minimum focus and, because it looks in focus, you think how wonderful the shots will be. But later you find out you need to consider the physical fact as quite hard and stop dreaming so much. I just this moment recalled some bad sessions with the M 200 due to a brick in my head. I checked the lens reviews a second ago and see the 200 4 has a minimum focus of 200 cm...that lens will give you some real surprises if your inner vision of beauty draws you into shots that require a hair more distance. I guess that's two thoughts, or rather a two cents worth, so that's enough.