[lytrytyr]

There is certainly no "AL" in the full name of the DA 40, unlike, say, the DA 21 AL.

[Sandy Hancock]

Hirakawa Jun designed the FA 43 and 77 Ltd lenses. The 43 matches the diagonal of the 135 film (full frame) making it the perfect "normal" lens. He chose 77 because of special meaning of 7. The target focal length was between 75 and 80 so he picked 77. He also designed the DA 40 Ltd perhaps inspired by the M 40/2.8

Thanks Blue. I am aware of all of that.
My comment was in reference to lytrytyr's fixed opinions with focal lengths of the film era and how they translate to APS-C. I have no argument with Pentax's quirky prime focal lengths; indeed it is one of the major factors leading to my loyalty to the brand.

[lytrytyr]

My comment was in reference to lytrytyr's fixed opinions with focal lengths of the film era and how they translate to APS-C. I have no argument with Pentax's quirky prime focal lengths; indeed it is one of the major factors leading to my loyalty to the brand.

What you call my "fixed opinions" concerned so-called normal lenses,
so 28-31mm on APS-C or 43mm on 35mm film.

Recently, I was looking for an AF short tele for street and similar use.
I did contemplate the FA 77 for that.
It lost out to the DA 70, not because of its focal length,
but because of the slowness of its AF in comparison with the DA.

[Sandy Hancock]

Recently, I was looking for an AF short tele for street and similar use.
I did contemplate the FA 77 for that. It lost out to the DA 70, not because of its focal length, but because of the slowness of its AF in comparison with the DA....

....and I got the DA70 for exactly the same reason. I still love the FA77 for its other qualities.
Even the "normals" (FA31 on APS-C, FA43 on film) have their merits, and when you reverse formats one becomes a wicked wide angle, and the other becomes an intriguing short tele.
It's all good.

[lytrytyr]

Even the "normals" (FA31 on APS-C, FA43 on film) have their merits, and when you reverse formats one becomes a wicked wide angle, and the other becomes an intriguing short tele.

You've raised an aspect that I'd never considered.

Was the FA 31 just designed as a wide angle for 35mm film use,
or did its design also deliberately anticipate "normal" use on APS-C?

[Blue]

There is certainly no "AL" in the full name of the DA 40, unlike, say, the DA 21 AL.

The lack of it in the name doesn't mean its not there. Nor does it being in the name make it a extremely well performing lens. An example is the various renditions of the 18-55 kit lenses. There was a time that an al element was an expensive aspect of lens construction. Now it depends on whether they are molded or ground and suspect the ones in the cheaper kit lenses are molded.

http://www.photozone.de/special-lens-elements

[Blue]

Are you absolutely sure of this? I have never heard of any of the Pentax 40mm lenses having any aspherical elements.

I am not absolutely sure on the AL and actually doubt it since it is a normal lens and have no other reference and can't pick the element out. I based that on Dimitrov. However, when he makes mistakes, it is usually an omission of a feature or spec rather than an inclusion. When I don't mention the al, someone invariable comes along and mentions Dimitrov.

DA 40/2.8 AL Limited

Special Features: aspherical element(s), ghostless coating

---

Last edited by Blue; 06-25-2012 at 08:09 AM.

[gofour3]

I think you are wrong. Think different etc. 43 might be a "true normal" (whatever that mean in practice) but 31 and 77 were selected for largely arbitrary reasons... the K 30 of yore was just as arbitrary, and the 77 was selected because it is a lucky number. That is what we call marketing. Pretty much every manufacturer created this line of lenses for a long time:

20, 24, 28, 35, 50, 85, 100, 135.

Think of it as an industry standard. I don't think it is a coincidence that NONE of the limiteds are any of those focal lengths. Marketing. Aren't I different? I shoot Pentax.

The point is, as far as focal lengths are concerned, the practical difference between 43 and 50 is nothing, between 31 and 35 is nothing, and between 77 and 85 is nothing. It just sounds hip. Like vinyl, high tops, and mustaches.

This is Pentax’s reasoning for the K30/2.8: “The perfect solution for those trying to choose between the 35 and 28mm focal lengths, as it lies between the two, making an excellent compromise.”

The same holds true for the K18/3.5, its half way between the K15/3.5 and K20/4.

On film there is a noticeable difference between the FOV on the FA43 and a 50/55mm lens. I can fit entire buildings into a shot with the FA43, it’s a lot harder with the 50/55 focal length.

Phil.

[lytrytyr]

The lack of it in the name doesn't mean its not there.

That may have been true back in the days of the K15/3.5,
but at least since the FA series,
Pentax nomenclature has included the AL for aspheric lens elements.

Compare the official site
Interchangeable Lenses : Digital Cameras : Products | PENTAX RICOH IMAGING

[Blue]

That may have been true back in the days of the K15/3.5,
but at least since the FA series,
Pentax nomenclature has included the AL for aspheric lens elements.

Compare the official site
Interchangeable Lenses : Digital Cameras : Products | PENTAX RICOH IMAGING

I explained why a said it may have an AL and I also said I had doubts. But I will put it up again:

DA 40/2.8 AL Limited

DA 40/2.8 AL Limited

He also listed it it under special features. And as I said, the rare time he makes mistakes, it is usually in the omission of a feature. I don't think it has an AL but I haven't seen the reference that he used to base that on. The name is certainly wrong. Then again, in 2004, maybe Pentax promotion blew it like they did initially with the DA 35/2.4 AL when Pentax Imaging was calling it a DA-L lens when it isn't. None the less, the bigger point in my post is the optics of the DA limited aren't the same as the M40/2.8. They only share the 5/4 layout and both are pancakes.

[lytrytyr]

I explained why a said it may have an AL and I also said I had doubts. But I will put it up again:

DA 40/2.8 AL Limited

I was indeed aware of your citation,
which is why I emphasized that I was linking to an official site.

[lytrytyr]

Then again, in 2004, maybe Pentax promotion blew it like they did initially with the DA 35/2.4 AL when Pentax Imaging was calling it a DA-L lens when it isn't.

It seems that Pentax now only uses the L designation for a lightweight lens
as a distinction when there is also a heavyweight equivalent (e.g. 18-55).

[Blue]

I was indeed aware of your citation,
which is why I emphasized that I was linking to an official site.

So what. The official site doesn't mention that some of the lenses with Ghostless have Ghostless coating. A prime example of that is the DA 35/2.4 AL. No mention of it in you link or this "official link."

PENTAX Digital Camera Lens Lineup

But it has Ghostless Coating just like the FA 35/2 had.

It seems that Pentax now only uses the L designation for a lightweight lens
as a distinction when there is also a heavyweight equivalent (e.g. 18-55).

That wasn't the point. The point was Pentax Imaging used a misnomer when the initially announced the lens. Plus, they fail to mention it has Ghostless Coating for some reason.

Edit: Regardless, the DA 35/2.4 and DA 50/1.8 could bear the L designation since the lack quick shift and have the plastic mount like the DA-L series of kit lenses.

[lytrytyr]

The official site doesn't mention that some of the lenses with Ghostless have Ghostless coating.

Right. Coatings haven't featured in the lens names since the days of "SMC."

[Blue]

Right. Coatings haven't featured in the lens names since the days of "SMC."

Wrong. SMC is still featured in lens names. Ghostless Coating has never been used in lens names. All Limited lenses have it as do certain others. It is generally listed somewhere in the specs, but not always as in the example of the DA 35/2.4 I gave above.

Even the new DA 50/1.8 officially has SMC in the name.





SMC Pentax-DA



2 of these 3 have Ghostless Coatings but it isn't given away by the name. All 3 have SP and it isn't given away by the name either.