[builttospill]

We need newer lenses with better coating than hanging on legends.

I just wanted to make sure everyone knows the FA Limiteds, although legends, aren't that old and have the very same coatings as the current SMC DA and DA* lenses. The SMC coating has been around for a while. There are only two Pentax lenses that I'm aware of that use the newer HD coating, the 560mm and the 645 90mm.

[sb in ak]

What's the difference between FA and DFA? I can't imagine Pentax dumping the FA's as the rumored FF camera seems more likely than ever. Maybe they mean to update them and relaunch beside the FF, so they're leaving them off for now. Anyways, weird they'd be left off. They seem to remain popular with the Pentax community.

[Wired]

What's the difference between FA and DFA? I can't imagine Pentax dumping the FA's as the rumored FF camera seems more likely than ever. Maybe they mean to update them and relaunch beside the FF, so they're leaving them off for now. Anyways, weird they'd be left off. They seem to remain popular with the Pentax community.

FA were designed for film. DFA are lenses designed for digital that cover the full 35mm frame. I believe they were FA lenses that were updated with digital coatings and calibration...

[Blue]

Again, 23 years ago there was an eerie and complete silence before Desert Storm (the first Iraq War). My business thricves on information and I recall being uncomfortable in the information vacuum.

Then January 17, 1991 there was "Shock and Awe," a massive and complete show of force by a coalition of 17 Nations.

Clearly it isn't a perfect analogy - Pentax doesn't have the comparative advantage in war materiel enjoyed by the Coalition Forces. But if you are a little guy and you want the complete attention of your market for a few months - and I do mean complete attention - then you and say Tamron, Sigma and Tokina might drop FF product after product after product on a skeptical market, month after month after month, forcing the eReview publishers, retailers, Forums, fanbois, haters and everyone else to talk about you - and not talk about anyone else - right through the holiday buying season.

Many many small indicators suggest this possibility (real product discontinuations like K-01 to free manufacturing lines, news embargoes, undeclared discontinuations of popular products, hints that are never repeated, a few new B&M distributions in the USA, Clearance Sales of distributor warehouses ---

Maybe, just maybe, I smell a hint of Shock and Awe on the summer breeze.

Doing away with the FA ltd series would be shock without the awe.

[ElJamoquio]

Doing away with the FA ltd series would be shock without the awe.

shock and awwwwwwwwwwwwwwwwwww!

[jsherman999]

I just wanted to make sure everyone knows the FA Limiteds, although legends, aren't that old and have the very same coatings as the current SMC DA and DA* lenses. The SMC coating has been around for a while. There are only two Pentax lenses that I'm aware of that use the newer HD coating, the 560mm and the 645 90mm.

Except AFAIK they don't have coatings on the rear element. This is a new thing for digital-age lenses, to mitigate the glare reflecting off the sensor cover itself.

.

[Blue]

Except AFAIK they don't have coatings on the rear element. This is a new thing for digital-age lenses, to mitigate the glare reflecting off the sensor cover itself.

.

Actually, all of the FA LTD and DA LTD lenses have the Ghostless Coating on the rear element.

The Ghostless Coating was announced in 1992 and is considered a milestone for Pentax. It was apparently 1st used in 1997 on the the FA 43mm ltd and all subsequent limited lenses as well as certain * lenses. However, besides the LTD lenses, the other lens it was used on is unclear.

I just wanted to make sure everyone knows the FA Limiteds, although legends, aren't that old and have the very same coatings as the current SMC DA and DA* lenses. The SMC coating has been around for a while. There are only two Pentax lenses that I'm aware of that use the newer HD coating, the 560mm and the 645 90mm.

There is also the Aero Bright Coating that is used on the DA* 55/1.4 and DA* 60-250mm. The Aero Bright Coating enhances image-description performance by effectively reducing reflections over a wider wavelength range. Compared to conventional multi-coatings, this new coating greatly improves light transmittance in the lens, while drastically reducing flare and ghost images that deteriorate image quality. They also have the SP Coating they use on the front lens of certain lenses. It is a protective coating.

---

Last edited by Blue; 04-16-2013 at 05:41 AM.

[Wired]

Canadians! Right now is the time to get the FA 43! $539!!! Check photoprice.ca. I just got my local store to price match and scored a made in Japan copy for less than USA imported

[Digitalis]

the Aero Bright Coating that is used on the DA* 55/1.4 and DA* 60-250mm. The Aero Bright Coating enhances image-description performance by effectively reducing reflections over a wider wavelength range. Compared to conventional multi-coatings, this new coating greatly improves light transmittance in the lens, while drastically reducing flare and ghost images that deteriorate image quality. They also have the SP Coating they use on the front lens of certain lenses. It is a protective coating.

Interesting information but it doesn't exactly describe what Aero bright is - but from what I have gathered from pieces of information I have seen "aero bright" is based on a nanocomposite silica aerogel designed to scatter and deflect stray light - the coating is only a fraction of a micron thick. The concept is similar to that of the anti-reflective thin-film nanostructures seen on the eyes of moths. Moths evolved these structures to reduce the reflectivity of their eyes so predators would find it harder to spot them, it also is suggested it increases visual acuity* - moths have small nanostructures on their eyes 200nm high with an ordered 300nm spacing, these structures are much smaller than the wavelengths of visible light (400-700nm). The practical upshot of this is that light interacts with the surface as if it has a continuous refractive index gradient between the air and the medium, which decreases reflection by effectively removing the air-lens interface. The nano crystal coat used by nikon is based upon a similar concept.

*though compound eyes better suited for insects that require wide FOV vision - the drawback is they typically do not resolve details as well.

[Wired]

just a quick thought... In light of picking up the last piece of my Pentax lens puzzle, I went to go read the in-depth FA 43mm review, having remembered that during the posting of the 10-17mm DA Fisheye that it was mentioned: "We are now only two lenses short (DA* 200mm and DA* 60-250mm) of having in-depth reviews of the entire (current) Pentax lens lineup!"

Maybe I'm just reading between the lines? Maybe the 43 was forgotten? Or maybe someone knows something.

[bossa]

Interesting information but it doesn't exactly describe what Aero bright is - but from what I have gathered from pieces of information I have seen "aero bright" is based on a nanocomposite silica aerogel designed to scatter and deflect stray light - the coating is only a fractions of a micron thick. The concept is similar to that of the anti-reflective thin-film nanostructures seen on the eyes of moths. Moths evolved these structures to reduce the reflectivity of their eyes so predators would find it harder to spot them, it also is suggested it increases visual acuity* - moths have small nanostructures on their eyes 200nm high with an ordered 300nm spacing, these structures are much smaller than the wavelengths of visible light (400-700nm). The practical upshot of this is that light interacts with the surface as if it has a continuous refractive index gradient between the air and the medium, which decreases reflection by effectively removing the air-lens interface. The nano crystal coat used by nikon is based upon a similar concept.

*though compound eyes better suited for insects that require wide FOV vision - the drawback is they typically do not resolve details as well.

Thanks for that info Doug... ..fascinating stuff.

[ak_kiwi]

Please correct me if I'm wrong but all the FA Ltd's are all screw drive as well as being FF aren't they?

[Digitalis]

all the FA Ltd's are all screw drive as well as being FF aren't they?

Correct.

[Blue]

Interesting information but it doesn't exactly describe what Aero bright is - but from what I have gathered from pieces of information I have seen "aero bright" is based on a nanocomposite silica aerogel designed to scatter and deflect stray light - the coating is only a fraction of a micron thick. The concept is similar to that of the anti-reflective thin-film nanostructures seen on the eyes of moths. Moths evolved these structures to reduce the reflectivity of their eyes so predators would find it harder to spot them, it also is suggested it increases visual acuity* - moths have small nanostructures on their eyes 200nm high with an ordered 300nm spacing, these structures are much smaller than the wavelengths of visible light (400-700nm). The practical upshot of this is that light interacts with the surface as if it has a continuous refractive index gradient between the air and the medium, which decreases reflection by effectively removing the air-lens interface. The nano crystal coat used by nikon is based upon a similar concept.

*though compound eyes better suited for insects that require wide FOV vision - the drawback is they typically do not resolve details as well.

Digitalis, if you go back and read the information that I have included in here https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/104892-pentax-...ro-bright.html, I already mentioned it was nano tech with silca aerogel and also listed the Nikon counter part as well as Canon. Furthermore this information regarding Aero Bright and HD came from Pentax info. Older coatings came from both Asahi and other sources. Also, the insect compound eye has nothing analogous to it and are mosaics and there are multiple types as well as diurnal and nocturnal. Hymenopterans show 3 major peaks at 340 nm, 430 nm and 535 nm and a small peak at 600 nm. Response above 600 nm is uncommon in insects.

[Blue]

Please correct me if I'm wrong but all the FA Ltd's are all screw drive as well as being FF aren't they?

The DA Ltd lenses are also screw drive only.