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02-04-2019, 05:13 PM   #31
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QuoteOriginally posted by nocturnal Quote
So Sony's new asph fabrication developments result in smaller and cheaper lenses. This is where it is at then and I don't like monster lenses if they don't have to be as big or costly.
I didn't read anything in that article that suggests Sony's methods will make lenses physically smaller. Just that the aspherical elements they're producing (or will produce) shouldn't suffer from the ridges inherent on some others, and that they can estimate the quality of out-of-focus rendering ("bokeh") during the design process, and before a lens is tested.

TL;DR... You can't make a small, light, full frame 24-70 f/2.8 out of decent materials. Because physics

02-04-2019, 05:52 PM   #32
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QuoteOriginally posted by BigMackCam Quote
I didn't read anything in that article that suggests Sony's methods will make lenses physically smaller. Just that the aspherical elements they're producing (or will produce) shouldn't suffer from the ridges inherent on some others, and that they can estimate the quality of out-of-focus rendering ("bokeh") during the design process, and before a lens is tested.

TL;DR... You can't make a small, light, full frame 24-70 f/2.8 out of decent materials. Because physics
It is in there about 1/3 - 1/2 way down the page just below the cutaway photo of the 85mm f1.4 which consequently 'only' weighs 820g which is lighter and smaller than the Pentax DFA 50mm f1.4.

---------- Post added 02-05-19 at 01:12 AM ----------

After reading the article it makes you wonder about using a 1999 lens design like the 35/2.

The modern Pentax lenses I think produce much nicer bokeh than the legacy designs, the HD DA Limiteds and all the new DFA lenses do it so well. If I'm back looking at pentagons/hexagons again well no I don't want to do that. I have a certain photo taken with the K35/3.5 with a massive pentagon right in the middle of it, I think it's time to move all these lenses on while they are still worth a bit of cash.
02-04-2019, 06:12 PM - 3 Likes   #33
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QuoteOriginally posted by nocturnal Quote
It is in there about 1/3 - 1/2 way down the page just below the cutaway photo of the 85mm f1.4 which consequently 'only' weighs 820g which is lighter and smaller than the Pentax DFA 50mm f1.4.
Ah, OK. Honestly. I wouldn't build up hopes on that too much just yet. Firstly, Sony doesn't have the monopoly on clever optical design, and then - as I said before - there's physics, and optical complexity, which will dictate minimum size of lenses. I'm sure Sony is doing a fine job, but I doubt it can produce a D*FA50/1.4 competitor that is optically as capable and physically much smaller or lighter without sacrificing quality. If it can, where is it?
02-04-2019, 06:59 PM   #34
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The article doesn't specify that the new process will make all of their lenses smaller / lighter. Only that the 85 would have been extremely heavy with all the correction elements needed to get what they wanted.

02-04-2019, 07:26 PM   #35
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QuoteOriginally posted by twilhelm Quote
The article doesn't specify that the new process will make all of their lenses smaller / lighter. Only that the 85 would have been extremely heavy with all the correction elements needed to get what they wanted.
It says this: "Extreme Aspherical elements for more compact, higher-performing lenses"

I imagine it would work for others too, why not? The Sony 70-200 f2.8 is lighter than the DFA* 70-200 f2.8 but size is about the same.

I don't know how well the Sony does against the DFA *50 f1.4 but I think it is possibly the best 50mm out there. I wonder how heavy the Pentax DFA* 85mm f1.4 version is going to be? Certainly heavier than 820g I would think but maybe better too.

If there is tech to make smaller and lighter for the same IQ I'm all for it.

I'll not be buying anything in that price range but the tech is interesting. ��

---------- Post added 02-05-19 at 02:33 AM ----------

BTW I know that certain focal length speeds and apertures require a minimum diameter but using less complex design could make lenses shorter. No certainly Sony does not have a monopoly with optics, maybe just this articles aspect of certain patents. I'm sure Pentax has 100s patents on camera gear.
02-05-2019, 12:43 AM   #36
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QuoteOriginally posted by nocturnal Quote
It says this: "Extreme Aspherical elements for more compact, higher-performing lenses"
...
If there is tech to make smaller and lighter for the same IQ I'm all for it.
There is a systematic problem with molded aspherical lenses until today and that is ugly bokeh, damaged by onion rings.
See: https://www.imaging-resource.com/news/2014/05/02/the-end-of-onion-ring-bokeh...spheric-lenses

Modern extra expensive (and not light or small) Zeiss lenses have this poor bokeh: http://www.verybiglobo.com/wp-content/uploads/2016/03/55_Crop_f14PD.jpg and it is caused by aspherical elements.

It is easy to correct certain optical flaws, but onion ring bokeh is not one of them.

Sigma lenses also have the problem due to the same reasons.

---------- Post added 5th Feb 2019 at 08:47 ----------

QuoteOriginally posted by Digitalis Quote
The nature of the polymer Zeiss is using for these lenses is unknown. It would be unlikely to be used in lens construction, as the properties of contact lenses and the requirements for bio-compatibility would make them different from what is required from precision optical elements.
The materials I linked to are for "glasses" not contact lenses. (I struggle with English language here) I would not expect them to have vastly different requirements to lens elements in photo lenses.

Last edited by beholder3; 02-05-2019 at 12:53 AM.
02-05-2019, 04:42 PM   #37
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QuoteOriginally posted by beholder3 Quote
Zeiss for example offers non-glass organic "plastic" lenses for human vision between index ranges from 1.5 to 1.74
QuoteOriginally posted by beholder3 Quote
The materials I linked to are for "glasses" not contact lenses.
Exactly what are you going on about here? optical plastics or glass?
02-06-2019, 02:45 AM   #38
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The A* 85 f/1,4 is very compact, has no rivals and has no special elements inside.

02-06-2019, 04:12 AM - 1 Like   #39
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QuoteOriginally posted by Andrea K Quote
The A* 85 f/1,4 is very compact, has no rivals and has no special elements inside.
I think we'll find the DFA* 85 f1.4 will be sensational, Andrea.

Won't be compact or cheap, though.

02-06-2019, 08:50 AM   #40
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QuoteOriginally posted by Digitalis Quote
Exactly what are you going on about here? optical plastics or glass?
I thought he was talking about eyeglasses, which are often made of optical plastics.

I used to have a pair of glasses with SMC coatings, 25 years ago... that was awesome, especially at night...

-Eric
02-07-2019, 02:17 AM   #41
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QuoteOriginally posted by clackers Quote
I think we'll find the DFA* 85 f1.4 will be sensational, Andrea.

Won't be compact or cheap, though.
Surely
02-07-2019, 08:05 AM   #42
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QuoteOriginally posted by Digitalis Quote
Exactly what are you going on about here? optical plastics or glass?
After looking into the dictionary:

I tried pointing out that the Zeiss material is used for spectacles (which mean large elements out of rock solid material and with virtually no contact to the body). Not for contact lenses which - as far as I know - either are made from solid glass or soft plastics.
And the lens material for spectacles in my little opinion has pretty similar requirements as photo lens material.
02-07-2019, 05:46 PM   #43
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QuoteOriginally posted by clackers Quote
I think we'll find the DFA* 85 f1.4 will be sensational, Andrea.

Won't be compact or cheap, though.
All true... I am completely agree and am looking forward to adding it to my collection yet in 2019. For now the FA 35 HD will have to tie my over!
02-07-2019, 06:59 PM   #44
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QuoteOriginally posted by gm4life Quote
All true... I am completely agree and am looking forward to adding it to my collection yet in 2019. For now the FA 35 HD will have to tie my over!
There's a lot to love about it.

02-07-2019, 07:01 PM   #45
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QuoteOriginally posted by TwoUptons Quote
I thought he was talking about eyeglasses, which are often made of optical plastics.

I used to have a pair of glasses with SMC coatings, 25 years ago... that was awesome, especially at night...

-Eric
The B&M shop where I get my eyeglasses made still has Pentax table cards and notepads and a wall clock.
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