[mikesbike]

I would take the FA 80-320 over this new DFA 70-210 any day. What the old FA lens gives up in sharpness (mostly toward the edges in the 150mm to 210mm range), it more than makes up for with it's rendering. And the FA lens is around 10 times less expensive than the DFA -- and lighter and more compact as well.

As I recall, this FA lens got a very good test rating way back when it was current, especially in the 80-200mm range. And in that range I believe it could keep to f/4.5 with good quality.

The FA 20-35mm f/4 is not expensive and a very good wide angle choice. For a relatively cheap lens on a FF body, the FA 35-80mm f/4-5.6 is surprisingly good. Since there are no really inexpensive D-FA lenses, the very good D-FA 28-105mm offering the lowest price and best value, these old FA lenses represent a good alternative, and save weight as well.

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Last edited by mikesbike; 06-16-2020 at 09:01 PM.

[leekil]

At ƒ4.5 wide open the DA 16-85 is 2456 lw/ph, neither of the DA 50 1.8 or 2,8 values mach it.
The DA 50 1.8 is 2551 lw/ph

I'm not sure you have made the best comparison. You're comparing a DA* against Pentax's second (or first?) cheapest lens, and in general that 50mm had not been considered as good as other similar primes, it is much less regarded than the DA 35. And the 20mm is kind of an extreme focal length.

[Rondec]

Others have said it, but it depends a bit on the FA zoom. The cheaper ones were pretty cheap and didn't have good build qualities or as good coatings. The expensive ones (the FA * in particular) are highly regarded, but are pretty big.

Not all of the FA primes are that highly regarded either. I own the FA 50 f1.4 for awhile and didn't like it very much. It needed stopping down quite a bit to sharpen up, didn't have great contrast, and was really prone to flare. But it is pretty cheap and if you shoot it in the right situation it will give excellent results.

[Ontarian50]

It's hard to compare qualities of lenses from different eras, because in many cases, the demands of the user varied quite a bit over those years.

In the 1960s, when Pentax had its lineup of excellent Takumar primes, the Spotmatic owner often was a shooter of slide film that got blown up big on the projection screen. Or shot fine grain black and white film in the goal of making sharp 8x10s or 11x14s in the home darkroom. Those lenses had to be sharp.


By the late 1980s, when AF cameras started their reign, the typical Pentax SF-10 owner shot colour print film and dropped it off at the local one-hour lab. Ninety-nine percent (or more) of those photos were never seen any larger than the 4x6 machine print - and camera lens makers knew it. This is how Tamron was able to woo photographers with their early 28-200mm lenses. So many people bragged to me how great and sharp their photos were with their new "do it all" lens, and couldn't understand why I lugged around three or four lenses in my bag. But, again, they almost never made any enlargements from their negatives, and never projected slides onto a big screen.

Soft edges, chromatic abberations were invisible on 4x6 prints, so there was no need to buy anything higher grade for those customers. Photographers who did the blowups, projection, and darkroom work, sought out the better lenses and were willing to spend more. And often that meant primes instead of zooms.

Nowadays, camera manufacturers are scrambling to crunch out optical perfection to meet the demands of us who can blow up our images to pixel level on our 4k screens looking for any flaw we can whine about in an on-line forum. Whether all these optical gems that cost big bucks and weigh a ton make our actual photographs any better is a topic for another day.

[normhead]

Others have said it, but it depends a bit on the FA zoom. The cheaper ones were pretty cheap and didn't have good build qualities or as good coatings. The expensive ones (the FA * in particular) are highly regarded, but are pretty big.

Not all of the FA primes are that highly regarded either. I own the FA 50 f1.4 for awhile and didn't like it very much. It needed stopping down quite a bit to sharpen up, didn't have great contrast, and was really prone to flare. But it is pretty cheap and if you shoot it in the right situation it will give excellent results.

I used mine once for a few test images, then wondered what all the fuss was about.
If anyone wants it drop by and pick it up.

---------- Post added 06-17-20 at 10:58 AM ----------

Nowadays, camera manufacturers are scrambling to crunch out optical perfection to meet the demands of us who can blow up our images to pixel level on our 4k screens looking for any flaw we can whine about in an on-line forum.

4k screens are much more forgiving than my old 2160x1600 27 inch.

[bdery]

Prime lenses designs have been optimized many decades ago.

And recently they have been completely overhauled, with 50s leaving the double Gauss behind in order to get those few % of further improvement.

Not only that Roger's post doesn't refer to "primes vs zooms".
It refers to "bargain primes vs bargain zooms."

Correct. As some have shown, it's still a mixed bag. Lenses like the 20-35 are still very well regarded, as is the 24-90 also. Those might bot be "bargain" lenses but they are not STAR lenses by any mean.

Lens design tools, available materials and manufacturing processes, as well as the users' ability to test their lenses in the film era all explain why those cheaper zooms haven't aged well.

[normhead]

I've read the patent for the FA 80-320. That lens was not designed to be a consumer grade lens. It was an ambitious design for its time -- the first 4x telephoto zoom Pentax had produced since the 70s. Unfortunately, by modern standards, the optic comes up short in the long end,

The DA 55-300 PLM is the modern standard for such lenses, among all companies according to some sites.

[disasterfilm]

I wonder how many other people can say this... I have simultaneously owned the FA*28-70, the D-FA 24-70, the Sigma EX DG 24-70, and the FA 24-90.

The FA* 28-70 is a fantastic lens among all of them... old, semi-modern, and most modern. In fact, if the FA* 28-70 was WR, I may not have even looked at the D-FA.
IQ holds up, for sure, on the K-1 and on the tighter pixel pitch of the KP.

Great lens all around.
The FA 24-90 is nothing to sneeze at either! Certainly given its more compact size, weight, and budget range.

[Alex645]

4k screens are much more forgiving than my old 2160x1600 27 inch.

Norm, please explain. I do not understand this in the context of having a 55" 4k screen and seeing how poorly older lower res videos look on them vs. how they once appeared fine on a 21" Sony Trinitron CRT.

[robbiec]

What has always puzzled me is the difference between FA series Primes and Zooms.

Nearly every prime is well regarded and some are thought of as having the best optics Pentax have ever produced with a few well know models still in production.

There is an equally wide range of zooms but with a few exceptions most have very low optical ratings.

I am well aware that designing a zoom is nowhere as straightforward as designing a prime but went wrong ?

Lens design has improved zooms over the last 15 years more so than primes. Also it has to be said that the majority of FA zooms did not have the quality associated with the prime range. The FA* might be exceptions but only the 250-600 stands out. Prime wise it took Pentax nearly 50 years to improve on the original 50. Simple answer to a good question. Before fans of the FA*S come after me look no further than the FA*80-200 vs DFA*70-200. I'd also argue that the DA*50-135 taking sensor size into account was an improvement over the previous gen, hampered by sluggish AF only and not optics.

[angerdan]

1. What has always puzzled me is the difference between FA series Primes and Zooms.
2. Nearly every prime is well regarded and some are thought of as having the best optics Pentax have ever produced with a few well know models still in production.
3. There is an equally wide range of zooms but with a few exceptions most have very low optical ratings.
4. I am well aware that designing a zoom is nowhere as straightforward as designing a prime but went wrong ?

1. That could be because of more zooms than primes in the FA series
2. Primes always have the advantage to be easier to design than zoom lenses
3. The best FA lens is of course a zoom and at least 29% of the best 24 FA lenses are zooms.
4. These are the rules of optics/physics. Much more complex to design. Good lenses needs mastermind lens designers like Jun Hirokawa.
   Jun Hirakawa - Wikipedia

Btw, here's an overview:

Average User Rating / Lens
10....FA* 250-600mm F5.6 ED [IF]
10....FA* 200mm F4 Macro ED [IF]
..9,9 FA* 300mm F2.8 ED [IF]
..9,7 FA* 85mm F1.4 [IF]
..9,7 FA 77mm F1.8 Limited
..9,7 FA* 200mm F2.8 ED [IF]
..9,7 FA* 300mm F4.5 ED [IF]
..9,6 FA 50mm F1.7
..9,5 FA 31mm F1.8 AL Limited
..9,5 FA* 80-200mm F2.8 ED [IF]
..9,5 FA 43mm F1.9 Limited
..9,5 FA 20mm F2.8
..9,3 FA* 24mm F2 AL [IF]
..9,3 FA 20-35mm F4 AL
..9,1 FA 35mm F2 AL
..9... FA* 600mm F4 ED [IF]
..9... FA 28mm F2.8 Soft
..9,0 FA 135mm F2.8 [IF]
..8,9 FA 50mm F1.4
..8,8 FA* 28-70mm F2.8 AL
..8,7 FA* 400mm F5.6 ED [IF]
..8,2 FA 28-105mm F4-5.6
..8,1 FA 24-90mm F3.5-4.5 AL [IF]
..8,1 FA 28-70mm F4.0 AL

[Serkevan]

1. That could be because of more zooms than primes in the FA series
2. Primes always have the advantage to be easier to design than zoom lenses
3. The best FA lens is of course a zoom and at least 29% of the best 24 FA lenses are zooms.
4. These are the rules of optics/physics. Much more complex to design. Good lenses needs mastermind lens designers like Jun Hirokawa.
   Jun Hirakawa - Wikipedia

1. 23 primes, 20 zooms, 3 FA-J zooms. Exactly a 50/50 split. Although the zooms have a lot of similar "walkaround" zooms covering different parts of the 28-105 range at variable apertures.
2. Absolutely true
3. Yeah, but if instead of an arbitrary 24 best lenses (why? The "better half" would be 23) we take a top 20, zooms are only 20%. The first position isn't "of course" a zoom because the FA* 200/4 Macro has more reviews so it should be in first place . Conversely, there are 0 primes under an 8/10 score (apart from the HD FA 35/2, which got only 4 reviews and one of them is a 6), while 13/23 zooms are under (or exactly at) 8/10. So the average score of primes is substantially higher than that of zooms.
4. Again, agreed.