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10-13-2011, 08:57 AM   #1
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Is there like a max focussing distance on 50 f1.4 primes ?

I got the FA50 1.4 recently (MY first prime and f1.4 lens) and was trying out taking pictures of subjects at about 20 feet away. But the pictures seemed soft, this was a at a relatively fast shutter speed of 1/80. Is this just softness of the lens wide open or is there like a max distance of sharpness on the lens at this wide aperture.

10-13-2011, 09:09 AM   #2
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If you read the reviews in the lenses section, I don't think the FA50 is particularly sharp until f2-2.8. You tend to get sharper 'looking' shots with a thin depth of field when you have the subject a little closer. If you focus further away or at infinity @ f1.4 everything tends to look a little smeared! Could you post any examples?
10-13-2011, 09:17 AM   #3
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Yeah more than likely because of the 1.4 aperture, take the same shot at F5.6 or higher and it should look much much sharper
10-13-2011, 09:19 AM   #4
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QuoteOriginally posted by markos Quote
If you read the reviews in the lenses section, I don't think the FA50 is particularly sharp until f2-2.8. You tend to get sharper 'looking' shots with a thin depth of field when you have the subject a little closer. If you focus further away or at infinity @ f1.4 everything tends to look a little smeared! Could you post any examples?
Well, this was taken with the FA 50/1.4 at 1.4, handheld on my K20d (iso 1600) with nothing but those street lights at the very end of the "Blue Hour." It really comes down to what one is trying to do and when.



10-13-2011, 09:25 AM   #5
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QuoteOriginally posted by StDevious Quote
I got the FA50 1.4 recently (MY first prime and f1.4 lens) and was trying out taking pictures of subjects at about 20 feet away. But the pictures seemed soft, this was a at a relatively fast shutter speed of 1/80. Is this just softness of the lens wide open or is there like a max distance of sharpness on the lens at this wide aperture.
The lens has a minimum focusing distance out to infinity. 1/80 isn't really fast especially if SR is off. However, given good light it is greater than 1/50 and should be adequate. However, if you are shooting with a wide aperture, the dof near the focus point becomes critical and you haven't given us much details.
10-13-2011, 10:21 AM   #6
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You may have to eliminate the other possibilities for lack of sharpness. The lens design is near the bottom of the likely causes. I think the top 4 possible causes would be camera shake, subject movement, SR not ready, and focus not where you thought it was. Some others are flare, which can reduce contrast where the sharpest focus was and look like softness. I sometimes have SR set to the wrong focal length, not possible with the FA50 but it does ruin sharpness. You could have a problem with AF, but make sure the top 4 problems are eliminated before chasing that one.
10-13-2011, 11:43 AM   #7
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The copy of the FA50 that I kept does the same, I think this is common for the model.
At f1.4 pictures have a sort of dreamy look, but it goes away at f2.
Maybe it is desirable for portraits?
If you are shooting outdoors I hear that a hood will improve the performance of the lens.

Last edited by crewl1; 10-13-2011 at 04:26 PM.
10-13-2011, 01:01 PM   #8
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FA 50 1.4 gets softer at wide apertures as you move towards infinity.

However this almost never matters... in low light, you have almost no alternatives, and for infinity work, even f2.8 is too wide (most of the foreground will be a blur).

10-13-2011, 02:48 PM   #9
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Like my K50/1.2 and SuperTak 50/1.4 and Yashica ML 50/1.4 and Tomioka 55/1.4, my FA50/1.4 is very sharp wide open. However, that sharpness is confined to a VERY THIN image field that isn't necessarily flat. These comments about 50/1.4 'softness' are quite true, for areas outside that minimal image field.

As I've mentioned before (who, me?) we don't use superfast lenses for edge-to-edge flatfield sharpness in a thick image plane. We use these beasts to GRAB LIGHT, to get otherwise impossible shots. As paperbag846 says, this is what matters. For thicker DOF, stop-down a shorter lens. To shoot what no other lens can, use a Fast Fifty wide-open.
10-13-2011, 02:55 PM   #10
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Speak for yourslef Rio, but myself and I know many others use fast lens for the small DOF.

For the OP, 50mm shooting at f/1.4 subjects 20 feet way will have a DOF of around 3 feet.
Could be a case of a soft lens or miss-focus.

Last edited by TOUGEFC; 10-13-2011 at 03:05 PM.
10-13-2011, 03:52 PM   #11
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QuoteOriginally posted by TOUGEFC Quote
Speak for yourslef Rio, but myself and I know many others use fast lens for the small DOF.
I think DOF control falls under "to get otherwise impossible shots". Maybe I was too succinct.

QuoteQuote:
For the OP, 50mm shooting at f/1.4 subjects 20 feet way will have a DOF of around 3 feet.
Could be a case of a soft lens or miss-focus.
I vote for mis-focus. [salacious pun deleted] Focusing with thin DOF in dim light can be tricky. Practice practice practice.
10-13-2011, 04:54 PM   #12
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QuoteOriginally posted by RioRico Quote
I think DOF control falls under "to get otherwise impossible shots". Maybe I was too succinct.

.
I guess it does, from a certain point of view
10-13-2011, 08:35 PM   #13
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The FA 50 is not particularly strong at infinity either wide open. This is in pixel-peeping language. In actual use, it is just fine wide open at infinity. However, compared to the likes of the 50 1.7 / FA 43, the 50 1.4 IS softer at equivalent apertures at infinity.

In the end, sharpness does not count for much though. It's more important to grab the light in a dark room than to see every pore on your girlfriend's face from across the room.
10-16-2011, 02:14 PM   #14
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I think there is next to zero chance this is anything but focus not being being where you thought it was (eg, you didn't give the camera an unambiguous focus target, and something else was within range of whichever focus sensor you selected), combined with DOF being shallower than you expect. Sample images would help prove or disprove this assertion, of course.
10-17-2011, 07:06 AM   #15
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QuoteOriginally posted by Marc Sabatella Quote
I think there is next to zero chance this is anything but focus not being being where you thought it was (eg, you didn't give the camera an unambiguous focus target, and something else was within range of whichever focus sensor you selected), combined with DOF being shallower than you expect. Sample images would help prove or disprove this assertion, of course.
I agree. I miss a lot of shots when shooting in the golden hour/blue hour and sometimes tricky shots in good light with 1.2 or 1.4, and it is generally miss focus either by me or pushing the camera af. Spot focus helps, but also can be part of the problem. keeping the camera level is probably my biggest problem.
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