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10-05-2016, 04:04 PM   #31
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QuoteOriginally posted by noelpolar Quote
F2 is where I start to use the K50/1.2 mostly.... I am quite fond of it...

Yeah, the danger with these very fast lenses without aspheric elements is that when wide open the bokeh in the background can be gorgeous and indistinct but the centre of the subject is mushy or glows with spherical aberration.

10-05-2016, 06:20 PM - 1 Like   #32
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QuoteOriginally posted by clackers Quote
Yeah, the danger with these very fast lenses without aspheric elements is that when wide open the bokeh in the background can be gorgeous and indistinct but the centre of the subject is mushy or glows with spherical aberration.
Yes... really for me... lenses like the K50/1.2 are in the "fun and explore" category.... they are not in the "get the job done" category.... take other stuff for that.
10-05-2016, 11:54 PM - 2 Likes   #33
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QuoteOriginally posted by clackers Quote
Thanks for posting these, Dan ... it's always interesting to see someone bothering to push the limits of these things.

Here's a Melbourne example:

Using Sony A7 II + Mitakon 50mm F0.95 for Wedding Photography | Melbourne Wedding Photographer Will Chao
I like to read a lot about lenses, cameras, flashes, etc. (stuff about photography in general) because almost in every article I find something useful: a little tip, a behind the scenes image, an interesting composition...

When it comes to photography, what I like most is that, no matter what I do, I never manage to recreate the same moment. There is always something different: mood, light, etc. Seeing photographers working with demanding lenses like Mitakon 50mm f0.95, Pentax DA* 55mm f1.4, Canon 85mm f1.2, Nikon 105mm f1.4, etc. helps me to:
- understand the importance of a calibrated lens (at f5.6 or f8 you can get away with a slight front/back focus of a lens, but at f1.2, f1.4, f1.8, you have more than 98% chances to miss the focus)
- understand the importance (and also the difference) in some cases of selecting focus point vs. focus and recompose technique. I'm shooting most of the time with focus and recompose technique and seeing the images from the link below I know that I have to work harder to be able to change rapidly the focus point and not rely only at focus and recompose technique
- etc.

Pirat pe Dun?re. Cu Nikon 105/1,4E. M?... - Mircea Bezergheanu | Facebook

Thank you also for showing the Metakon 50mm f0.95 images.

---------- Post added 10-06-16 at 07:06 AM ----------

QuoteOriginally posted by noelpolar Quote
I'm not sure that if this shot was mine that I'd wouldn't have wished I'd opened up the lens a bit... maybe a stop?
Maybe...who knows? I love the image because seeing that old man with his dirty hands and with that traditional hat on his head reminds me (and I think to a lot of Romanians) about my grandfathers who worked hard their land back in their days. And he also reminds me about me at 6-8 years old when all day long I was playing and helping my grandparents picking apples, grapes, etc. Lots of memories...
10-06-2016, 08:26 PM - 2 Likes   #34
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QuoteOriginally posted by Dan Rentea Quote
- understand the importance of a calibrated lens (at f5.6 or f8 you can get away with a slight front/back focus of a lens, but at f1.2, f1.4, f1.8, you have more than 98% chances to miss the focus)
Yeah, I think once you get to f1.4, f1.2 it can be too difficult.

You almost go down the path of a tripod, a cooperative subject keeping as much as possible in the same plane and manual focus. AF might happily go for the nose rather than the irises, with disastrous results.

I like Martin Schoeller's series of celeb portraits built around super shallow DoF. They often have double rectangular catchlights which I don't love when he uses continuous lighting, and they're more reminiscent of Richard Avedon than Annie Liebovitz, his previous employer.




Last edited by clackers; 10-06-2016 at 08:31 PM.
10-06-2016, 08:51 PM   #35
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QuoteOriginally posted by clackers Quote
he uses continuous lighting
I don't know, but it must be possible that continuous lighting allows focus bracketing, where the photographer moves the camera back and forth to get different features in that very thin zone of focus. It would be too distracting to have strobes firing 4 times a second, but if the model holds the same expression for a few seconds, the photographer can pick which of the dozen shots has the eyes or nose or lips in focus and everything else blurry, to suit whatever look the photographer had in mind. Reminds me of trying to photograph a flower handheld with my A 50 at f1.7, I basically rocked back and forth a little bit with continuous shooting in the hope that one shot had the right parts in focus because if I tried focus peaking I was moving too much between adjusting the lens and pushing the shutter button. (Or I could be out to lunch, it turned out my best flower pictures are at f2.8)
10-06-2016, 10:13 PM   #36
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QuoteOriginally posted by clackers Quote
You almost go down the path of a tripod, a cooperative subject keeping as much as possible in the same plane and manual focus. AF might happily go for the nose rather than the irises, with disastrous results.
for this kind of situations, I usually shoot 3-5 shots to be sure that one will be in focus
10-07-2016, 03:53 AM - 1 Like   #37
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QuoteOriginally posted by leekil Quote
thought that the DSLR sensors can't actually take full advantage of faster lenses, so there is no great advantage to super-fast lenses.


Pentax K5IIs - Aperture and shutter speeds were identical for both images, the only thing that changed was the lens aperture.
10-08-2016, 04:02 AM   #38
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If the cameras truly couldn't handle f/1.4 AF, they wouldn't build f/1.4 AF lenses for them (and Pentax has now built three generations of these - F, FA, DA).

10-11-2016, 11:58 AM   #39
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QuoteOriginally posted by Digitalis Quote

Pentax K5IIs - Aperture and shutter speeds were identical for both images, the only thing that changed was the lens aperture.

The contention is that the ISO is fudged, because the "T-stop" of the sensor makes the light gathered significantly less than what you should get from that aperture.
10-11-2016, 12:51 PM   #40
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QuoteOriginally posted by leekil Quote
The contention is that the ISO is fudged, because the "T-stop" of the sensor makes the light gathered significantly less than what you should get from that aperture.
The same amount of light enters the lens regardless of aperture setting, and the same losses in transmission and reflection occur in every element and surface up to the aperture stop. For this contention to be rational, it would mean that relative losses at and beyond the aperture stop would have to be increased as it opened up. Further, there would have to be an algorithm within the camera's circuitry that detected that change, and "fudged" the ISO setting to suit. This is starting to look dangerously like magical thinking, overlaid with a conspiracy theory.

Last edited by RobA_Oz; 10-11-2016 at 06:32 PM.
10-11-2016, 05:35 PM   #41
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QuoteOriginally posted by RGlasel Quote
I don't know, but it must be possible that continuous lighting allows focus bracketing, where the photographer moves the camera back and forth to get different features in that very thin zone of focus. It would be too distracting to have strobes firing 4 times a second, but if the model holds the same expression for a few seconds, the photographer can pick which of the dozen shots has the eyes or nose or lips in focus and everything else blurry, to suit whatever look the photographer had in mind.
Yes, it is very similar to handheld macro photography, when you're not using AF at all but rocking the body back and forth while taking frames.
10-11-2016, 10:50 PM   #42
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QuoteOriginally posted by RobA_Oz Quote
there would have to be an algorithm within the camera's circuitry that detected that change, and "fudged" the ISO setting to suit.
The thing is the SMCP-K 50mm f/1.2 has no electronic coupling therefore: the imaging pipeline* in Pentax cameras has no flipping idea what the lens is doing. Canon DSLRs where lenses do communicate with the camera, it has been discovered the imaging processing pipeline has been found to be compensating for losses (especially at the periphery of the imaging circle) with fast f/1.2~f/1.4 lenses. With the lens coding blacked out**: the Leica Monochrom likewise does not show any significant alterations when used with the Noctiluix 50mm f/0.95 or 50mm f/1.0

QuoteOriginally posted by RobA_Oz Quote
This is starting to look dangerously like magical thinking, overlaid with a conspiracy theory.
I agree. Arguing with someone who has arrived to an irrational conclusion with rational arguments is fruitless.

*sensor, AD converters, PRIME processing et al
** Black and white marks on the lens which are read by a code reader on the lens mount. There is only a slight difference in the amount of vignetting with these two lenses with lens corrections enabled. With a whopping -4.8EV of vignetting in the extreme corners on the 50mm f/0.95 I suppose Leica engineers threw their hands up in exasperation and let the lens just be what it is.

Last edited by Digitalis; 10-12-2016 at 02:00 AM.
10-12-2016, 03:42 AM   #43
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I don't see a big reason to shoot with an f1.2 lens over an f1.4 with regard to light gathering or depth of field. I would say that f1.2 lenses, generally speaking, have better designs and therefore will have better transitions from in focus to out of focus, better rendering of out of focus areas, and will be sharper one stop down. This is particularly true with Canon, where the 50mm f1.4 has bokeh that is a little on the rough side, while the 50mm f1.2 is much smoother in appearance. I do think the DA *55 is a pretty good option that is a major step up from the FA 50 f1.4 with regard to sharpness and rendering.

Looking at the f1.2 thread, the majority of images that are posted there would have been better if they had been shot at f2 or even f4. I know people sort of fall in love with narrow depth of field, but part of sharpness is actually being able to see the thing you are photographing and not have half of it be a blurry mess.
10-12-2016, 03:47 AM - 2 Likes   #44
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QuoteOriginally posted by Rondec Quote
I don't see a big reason to shoot with an f1.2 lens over an f1.4 with regard to light gathering or depth of field.
Sometimes that half stop of light gathering ability is the difference between getting the shot...and not. Though I agree with you on the second point, there are some images where stopping the lens down would have made the image more effective....but really, what did you expect from an f/1.2 thread? every shot taken at f/16?
10-12-2016, 06:08 AM   #45
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QuoteOriginally posted by Digitalis Quote
Sometimes that half stop of light gathering ability is the difference between getting the shot...and not. Though I agree with you on the second point, there are some images where stopping the lens down would have made the image more effective....but really, what did you expect from an f/1.2 thread? every shot taken at f/16?
Probably not. But there is some happy medium, not?
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