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03-15-2016, 08:26 AM   #46
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QuoteOriginally posted by normhead Quote
Now, to my old school mind, that's what ƒ1.4 lenses were made for.
Absolutely, and interesting that we get 3 pages into this thread before it was explicitly stated. My Sigma 50 1.4 is the default lens on my k7. I only shoot available light and love a fast lens as it allows me to reduce high iso noise. As sensors get better f1.4 will be less necessary for me. I like the sdof look every once in a while, but would rather be able to shoot at f2+. The K1 will be a boon for me due to the super low sensor noise as compared to the k7 and my GR.

---------- Post added 03-15-2016 at 10:51 AM ----------

QuoteOriginally posted by LensBeginner Quote
as a matter of fact, I have... but as I said, nothing comes for free.
regarding the validity of my original point, I merely said it's one more thing that enters the equation. The fact that it doesn't affect all the lenses in existence does't render my point less valid.
Yes, and to your point I seem to remember some up in arms over the up-dates to the rounded blades in the limiteds. Apparently the 15Limited is renowned for its starbursts, and there was fear that Ricoh was going to screw this up by rounding the blades. Mmmv from reality.

03-15-2016, 09:06 AM   #47
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QuoteOriginally posted by Alex645 Quote
If your aperture is working correctly*, you should see the finder become lighter or darker with each change in f/stop using your method. With a modern lens, you can do this by checking the depth-of-field preview.

Keep in mind, your own eye has an iris/aperture that will adjust as you see brighter or darker images. Your brain is also doing its own auto ISO as well.

The difference between f/1.4 and f/1.8 is the same as f/2.8 and f/3.5, or f/4 and f/4.5, etc. If you've got great eyes and/or you're using AF, this is not a big deal. If you've got aging eyes, like me, and you prefer to manually focus, it makes a difference. As much of a difference as a Canon Rebel or Nikon D3300 pentamirror and any Pentax pentaprism? No. As much of a diff from an 18-55mm f/3.5 kit lens vs. a 50mm f/1.8? No. But in real world terms the f/1.8 on a 50mm prime is 50mm/1.8=27.8mm diameter aperture vs. f/1.4 on a 50mm focal length is 50mm/1.4=35.7mm diameter aperture. Bigger iris/aperture diameter by roughly 8mm.
Try it yourself. I had some time so I tried it with all my fast lenses and a stock K-7 focus screen. It's not just the aperture size that matters here, it's the focus screen design. The best change I could see was using a DA*55/1.4, from f2.0 to f2.4. I can't see any brightness change from f1.4 to f2.0 at all. My Cosina 55/1.2 is roughly the same, but the Cosina aperture ring only has clicks at f2 and full stops through f16, so it's hard to say what the exact aperture is between them.
03-15-2016, 10:55 AM   #48
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QuoteOriginally posted by normhead Quote
Isn't Quebec City the "old world charm" kind of place?
Yes, I think. I've never been to either; both are on my list.
03-15-2016, 12:05 PM   #49
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Truth is we shouldn't generalize on aperture value alone. Pentax 1.4's were entirely different designs from Pentax 1.7's/1.8's, optimized for different prirposes. Suggesting f/1.4 universally 'means' something, such as stopping down to the same aperture as a cheaper lens makes them superfluous, is a false assertion.

Use the lens suited to the image you are trying to create. Often at f/2.8 an f/1.4 lens will render a different subject isolation with softer edges than an f/1.7 will. There are reasons other than paper thin DoF for wide apertures; including viewfinder brightness.

03-15-2016, 02:14 PM   #50
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QuoteOriginally posted by Just1MoreDave Quote
It's not just the aperture size that matters here, it's the focus screen design. The best change I could see was using a DA*55/1.4, from f2.0 to f2.4. I can't see any brightness change from f1.4 to f2.0 at all.
Yes, I'm sure the focus screen design may inhibit seeing this nuance, but I know I can see a difference in poor light where my own pupil/iris is wide open trying to help me focus. The f/1.4 is brighter than the f/1.8. In daylight or higher EVs, it's almost impossible to see this because the overall levels are so high.
03-16-2016, 05:23 AM   #51
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QuoteOriginally posted by normhead Quote
Isn't Quebec City the "old world charm" kind of place?
QuoteOriginally posted by Marktax Quote
Yes, I think. I've never been to either; both are on my list.
You're right about Quebec city. I'd say Montréal has more to do, Québec city more to see.
03-29-2016, 01:19 AM   #52
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QuoteOriginally posted by mohb Quote
Why is f1.4 so important?
QuoteOriginally posted by Kerrowdown Quote
Because it's slower than my F1.2.
f/1.2 is slower than my Noctilux 50mm f/0.95 ASPH... I stop DOWN to f/1.2.
03-29-2016, 02:55 AM   #53
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QuoteOriginally posted by Digitalis Quote
f/1.2 is slower than my Noctilux 50mm f/0.95 ASPH... I stop DOWN to f/1.2.
I wondered if you were around to see this, as your the only one I know with a Noctilux.

03-29-2016, 03:38 AM   #54
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QuoteOriginally posted by Digitalis Quote
f/1.2 is slower than my Noctilux 50mm f/0.95 ASPH... I stop DOWN to f/1.2.
Braggart.

Everybody wants a 10-600mm constant-f/0.95 for their brand new K-1, but they all want it packed inside the volume of a DA15 - nobody wants to make the sacrifices in weight, cost or IQ.
03-29-2016, 05:33 AM - 1 Like   #55
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QuoteOriginally posted by pathdoc Quote
Everybody wants a 10-600mm constant-f/0.95 for their brand new K-1
I'm pretty sure there's one of those on eBay - you just screw it into the front of your existing lens and it does everything you could ever want, for $30. Professional high definition lens. Honest.
03-29-2016, 06:53 PM   #56
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Remember when SLRs became popular starting in the 1960's most models had rather dim focusing screens.
A faster lens gave a brighter viewfinder image, and most opted for the 55mm f/1.4 lens if they could afford it.

Chris
04-02-2016, 03:11 PM   #57
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QuoteOriginally posted by normhead Quote
When I do my own images with the Sigma 70 2.8 macro, I always shoot a different ƒ-stops and select the one I like. So, what I'd like to see is, what does this image look like at 1.7 or 2 or 2.4 or 2.8? While the above is a very nice picture, I have nothing to compare it with. SO as a non-1.4 owner, it leaves me with more questions than it answers. My first question would be, how would it have looked with my 70 2.8, which is my favourite portrait lens among the ones I own. But then, I tend to look for reasons not to buy lenses, and buy the least I can get away with, unless they are under $80, in which case I'll buy them just to play with them.
Well basically the dog would be a bit sharper and the girl a bit less out of focus, and the more you'd close down, the more you'll accentuate the effect. Looking at the distance the picture was taken, there would lot of out of focus areas at f/8...

As to what give the best esthetical result, this is personal and depend of what you are really after. I guess f/1.4 was used because it was the widest apperture so if the photographer had an f/1.2 or f/0.85 lens it would have used this setting. That doesn't mean the result would have been any better objectively.

I tend to think that for artistic purpose, the composition, light etc are all much more important. Shallow deph of field is an important topic but the difference between f/1.4 and f/1.7-8 is too small to make or break a photo to me except for the cases of course when the lens is not providing enough quality at f/1.4... And that's quite common.
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