[Sandy Hancock]

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Dream cream is a word that does not sound positive talking about a lens.

Some people have the ability to put a negative spin on anything. You seem to be one of those people. Congratulations.

I would assume Asahi Man is not a native English speaker, and "dreamy" rendering and "creamy" bokeh are pretty much universally considered to be complimentary terms when used about a lens.

[Serkevan]

The dfa 50 isn't well corrected for pf and loca even if forum members claim it is. By the sounds of it the dfa 85 will be better corrected.

The thing is that strong LoCA corrections tend to lead to harsher bokeh; since the samples shown with the 85 have no such problem, it's safe to assume that the engineers went absolutely all-in in ensuring that the lens will be amazing, at the cost of... cost (and weight, unless they came up with some magical glass that can remove aberrations while keeping a creamy bokeh).

[Mistral75]

The thing is that strong LoCA corrections tend to lead to harsher bokeh (...)

I'm not so sure. True apochromatic lenses have nice bokeh more often than not. Think of the Voigtländer Macro Apo-Lanthar 125mm f/2.5 SL for instance.

[house]

The thing is that strong LoCA corrections tend to lead to harsher bokeh

I've also heard this but

I'm not so sure. True apochromatic lenses have nice bokeh more often than not. Think of the Voigtländer Macro Apo-Lanthar 125mm f/2.5 SL for instance.

There are quite a few examples that show it's not true the Leica SL f2 apo's come to mind in addition to Mistrals example.

[Serkevan]

Yep, there are a lot of apo designs (particularly macros from what I've seen?) that have low LoCA with smooth bokeh... although, like the Leica SL's, they all seem to be large and heavy - so maybe the thing is that to have both apochromatic design and nice, smooth bokeh you have to go ham with the design? I don't know nearly enough about optics honestly, so I would love to be educated - Wikipedia and other "entry level" sources haven't been too helpful so far .

[beholder3]

Yep, there are a lot of apo designs (particularly macros from what I've seen?) that have low LoCA with smooth bokeh... although, like the Leica SL's, they all seem to be large and heavy - so maybe the thing is that to have both apochromatic design and nice, smooth bokeh you have to go ham with the design? I don't know nearly enough about optics honestly, so I would love to be educated - Wikipedia and other "entry level" sources haven't been too helpful so far .

This an apples to oranges claim.

#1 Chromatic aberrations have a lot to do with the angles at which light is bent. So If you want to give apochromatic counterexamples, you absolutely do need to give F1.4 examples to be on par. Feel free to wonder why there are so few apochromatic F1.4 lenses...

#2 The harshness of bokeh has a lot to do with spherical aberrations. If these are overcorrected, then you get disgusting highlighted rings around the bokeh balls. Normally you want the exact opposite (soft edges), not even neutral ones. So "undercorrection" is good for bokeh here.


A good source is:
On Bokeh

In the sample images you can see that there is quite visible green/magenta coming with all this as well.

It is also a very good article to see that a lens can have good bokeh behind the subject and at the same time have bad bokeh in front of it.

[Serkevan]

This an apples to oranges claim.

#1 Chromatic aberrations have a lot to do with the angles at which light is bent. So If you want to give apochromatic counterexamples, you absolutely do need to give F1.4 examples to be on par. Feel free to wonder why there are so few apochromatic F1.4 lenses...

#2 The harshness of bokeh has a lot to do with spherical aberrations. If these are overcorrected, then you get disgusting highlighted rings around the bokeh balls. Normally you want the exact opposite (soft edges), not even neutral ones. So "undercorrection" is good for bokeh here.


A good source is:
On Bokeh

In the sample images you can see that there is quite visible green/magenta coming with all this as well.

It is also a very good article to see that a lens can have good bokeh behind the subject and at the same time have bad bokeh in front of it.

Thanks a lot for the link! Your #2 is what I remembered about the solid edges - I somehow conflated it with the chromatic aberrations.

[Twino4u]

Release date 28.05
2099 GBP


HD PENTAX-D FA85mmF1.4ED SDM Prime Telephoto lens: Amazon.co.uk: Camera & Photo

[Paul the Sunman]

Release date 28.05
2099 GBP


HD PENTAX-D FA85mmF1.4ED SDM Prime Telephoto lens: Amazon.co.uk: Camera & Photo

Expensive!

According to the specifications on this Amazon page, the maximum focus distance is 99999 millimetres, i.e., only 99.999 metres, which is not very far. It doesn't focus to infinity!

Edit: Whoops, my mistake. That's focal LENGTH, not focal distance!! Thanks Mistral75 for pointing that out.

[MikeyBugs95]

£2099 for a lens that doesn't focus to infinity!? It's horrible! Terrible! Overpriced! Completely not worth the price!

/s

[Mistral75]

From the link above:

1. New-generation, high-performance Star-series lens to deliver ideal image quality
   
   Anticipating the further advancement of SLR camera bodies in the future, PENTAX has designed this lens to deliver extra-clear, high-contrast images with edge-to-edge sharpness by compensating various aberrations to a minimum, while greatly enhancing resolving power — two factors absolutely essential in the next-generation Star series. It provides exceptionally high imaging performance even at open aperture, a beautiful bokeh (defocus) effect and outstanding image rendition at close ranges — all reasons why it produces high-quality, well-defined images. It also boasts an extra-large F1.4 maximum aperture, useful with many different subjects in a range of applications, including portraiture with an effectively defocused background, handheld shooting of indoor scenes and scenic photography. It helps the camera to produce a bright, clear viewfinder image that will inspire the photographer’s creativity and imagination.
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2. State-of-the-art optical technology
   
   This lens incorporates three Super ED (Extra-low Dispersion) glass optical elements to effectively minimize chromatic aberration, and a glass-molded aspherical optical element to effectively compensate for spherical and chromatic aberrations and field curvature to deliver extra-clear, high-contrast images with edge-to-edge sharpness, even at open aperture. It also reduces distortion to nearly zero at a focusing distance of four meters to deliver well-defined, distortion-free images over the entire focusing range, from the minimum focusing distance to infinity. This lens is also treated with high-grade, multi-layer HD* Coating, which reduces average reflectance in the visible ray spectrum to less than 50% of conventional multi-layer coatings, effectively reducing flare and ghost images to a minimum even in demanding lighting conditions such as backlighting.
   
   * HD is the abbreviation of High Definition.
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3. Newly designed, large ring-type SDM
   
   In order to deliver the highest image quality possible over the entire focusing range — from the minimum focusing distance to infinity — this lens features a newly designed, large ring-type SDM to efficiently drive the focusing mechanism, which consists of a larger number of optical elements than ordinary lenses, and is required to shift heavy rear-optical-element groups in unison. Generating a torque approximately 1.3 times that of the unit installed in the HD PENTAX-D FA★ 50mm f/1.4 SDM AW, this new SDM assures flawless, high-speed autofocus operation.
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4. Dustproof, weather-resistant construction
   
   Developed as an AW (All Weather) model, this lens features a dependable dustproof, weather-resistant construction with eight special seals to prevent the intrusion of water into the lens barrel. When paired with a dustproof, weather-resistant PENTAX digital SLR camera body, it assures a durable, reliable digital imaging system that performs superbly in demanding shooting settings — even in rain or mist, or at locations prone to water splashes or spray.
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5. Other features
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   • Nine-blade, round-shaped diaphragm to produce a natural, beautiful bokeh (defocus) effect up to the f/2.8 aperture setting, while minimizing the streaking effect of point light sources
   • Exterior design that facilitates focus-ring operation in manual-focus shooting and provides a firm hold
   • Electromagnetic diaphragm-control mechanism** for flawless, high-precision exposure control during video recording
   • SP (Super Protect) coating to keep the front surface free of dust and spots
     
     ** This mechanism is available when the lens is mounted on a K-1 Mark II, K-1, K-3 II, K-3, KP, K-70, K-50, K-S2 or K-S1 camera body.

[Mistral75]

(...)

According to the specifications on this Amazon page, the maximum focus distance is 99999 millimetres, i.e., only 99.999 metres, which is not very far. It doesn't focus to infinity!

Nope, according to them it's a zoom lens with a 850-99,999 focal length range.



A 850-99,999mm f/1.4 for £2,099.59, that's quite cheap!

[Serkevan]

No info on weight but considering that the package weighs 1.8 kg, I'm betting on the lens being ~1200 g. Ouch.

Although I also guessed on 1700€ and it seems I've missed by almost an entire grand

[JensE]

Interesting that they managed to work with less elements than in the 50/1.4, which has 15 elements in 9 groups. No mention of Aero Bright Coating II either.

[Mistral75]

No info on weight but considering that the package weighs 1.8 kg, I'm betting on the lens being ~1200 g. Ouch.

Although I also guessed on 1700€ and it seems I've missed by almost an entire grand

The HD Pentax-D FA★ 50mm f/1.4 SDM AW's package weighs 1.56kg whilst the lens itself weighs 953g. That would indeed put the HD Pentax-D FA★ 85mm f/1.4 ED SDM AW between 1.1 and 1.2kg.

Remember that the Sigma 85mm f/1.4 DG HSM | Art weighs 1,130g (Sigma SA mount).

The RRP at launch of the HD Pentax-D FA★ 50mm f/1.4 SDM AW was $/€/£1,199 therefore, even though £2,099.59 is theoretically equivalent to €2,345 and $2,129, there is a possibility that the RRP at launch of the HD Pentax-D FA★ 85mm f/1.4 ED SDM AW be $/€/£2,099.