[cyberjunkie]

I have two FA lenses, a 35mm f/2 AL and a 50mm f/1.4, that i will try soon with my new K-1.
Going by instinct, i'd say that both of them should be better of their cheaper corresponding alternatives in the DA range: the 35mm f/2.4 and the 50mm f/1.8, both with plastic bayonet but very appreciated by forum users for their very good price/performance ratio.
Am i right?
It happens that both DA lenses, available for super cheap on the used market, cover very well the full frame.
Though much more recent, i am not sure they would outperform good old film-era glasses.
Does anybody have personal experience, and made a quick comparison.
I am interested mainly in image quality, i know that the old F and FA lenses (albeit looking often wobbly) were of good mechanical quality, and personally i like to have a physical diaphragm ring, but now i'm jut curious to know if improved coatings and renewed optical projects actually improved image quality, even in economically priced lenses.

cheers

Paolo

[robthebloke]

I'd stick with the FA lenses tbh. The only one that (on APSC) can stand tall with the FA's, is the DA50 (the coatings seem to be a bit better for flare, but the CA's are pretty bad until f2.8). I briefly played around with it on the k-1, but it didn't quite have the sparkle of the FA50. I ended up selling both, and keeping hold of the FA43.

[Buffy]

I have two FA lenses, a 35mm f/2 AL and a 50mm f/1.4, that i will try soon with my new K-1.
Going by instinct, i'd say that both of them should be better of their cheaper corresponding alternatives in the DA range: the 35mm f/2.4 and the 50mm f/1.8, both with plastic bayonet but very appreciated by forum users for their very good price/performance ratio.
Am i right?

Probably, with caveats. I am not fond of the plastic bayonet so I consider both your lenses superior to the DA counterparts on that basis alone. With regard to performance, the FA 35 f/2 is wonderful, remarkably sharp, it was all but glued onto my camera until I got the 31mm Ltd. The FA 50 f/1.4 is more iffy. I also previously owned the the FA 50 f/1.7 and found it sharper than the f/1.4 wide open, although it is a half stop slower. Nonetheless, I prefer it over the DA 50 f/1.8.

[W.j.christy]

I have two FA lenses, a 35mm f/2 AL and a 50mm f/1.4, that i will try soon with my new K-1.
Going by instinct, i'd say that both of them should be better of their cheaper corresponding alternatives in the DA range: the 35mm f/2.4 and the 50mm f/1.8, both with plastic bayonet but very appreciated by forum users for their very good price/performance ratio.
Am i right?
It happens that both DA lenses, available for super cheap on the used market, cover very well the full frame.
Though much more recent, i am not sure they would outperform good old film-era glasses.
Does anybody have personal experience, and made a quick comparison.
I am interested mainly in image quality, i know that the old F and FA lenses (albeit looking often wobbly) were of good mechanical quality, and personally i like to have a physical diaphragm ring, but now i'm jut curious to know if improved coatings and renewed optical projects actually improved image quality, even in economically priced lenses.

cheers

Paolo

I'd not be to fast on assuming the FA's will out performs the DA's. Especially with the nifty 50's. Take a look at this Pentax 50mm Prime Lens Shootout Review - Introduction | PentaxForums.com Reviews it shows that hte 50 1.4 and the 50 1.8 are very evenly matched. Which is also my experience as well.

I would say this, the large aperture makes for an interesting focussing experiment as the depth of field is extremely shallow with the 50 1.4. The difference between focussing the 50 1.4 and the 50 1.8 is noticeable so keep that in mind.

Then there is this review of the 35 2.4 Pentax-DA 35mm F2.4 AL Review - Introduction | PentaxForums.com Reviews. Although I am not a good person to ask about the 35 2.4 as I never did like it, sold and and then bought the DA Limited 35mm. Honestly though, you can't really go wrong with any of those lenses they are all very good performers.

[Blue]

I'd not be to fast on assuming the FA's will out performs the DA's. Especially with the nifty 50's. Take a look at this Pentax 50mm Prime Lens Shootout Review - Introduction | PentaxForums.com Reviews it shows that hte 50 1.4 and the 50 1.8 are very evenly matched. Which is also my experience as well.

I would say this, the large aperture makes for an interesting focussing experiment as the depth of field is extremely shallow with the 50 1.4. The difference between focussing the 50 1.4 and the 50 1.8 is noticeable so keep that in mind.

Then there is this review of the 35 2.4 Pentax-DA 35mm F2.4 AL Review - Introduction | PentaxForums.com Reviews. Although I am not a good person to ask about the 35 2.4 as I never did like it, sold and and then bought the DA Limited 35mm. Honestly though, you can't really go wrong with any of those lenses they are all very good performers.

Those faster FA's are going to focus wide open. For example, the FA 50/1.4 will be autofocusing at f1.4 even if you have the aperture set at f5.6

[aurele]

I have two FA lenses, a 35mm f/2 AL and a 50mm f/1.4, that i will try soon with my new K-1.
Going by instinct, i'd say that both of them should be better of their cheaper corresponding alternatives in the DA range: the 35mm f/2.4 and the 50mm f/1.8, both with plastic bayonet but very appreciated by forum users for their very good price/performance ratio.
Am i right?
It happens that both DA lenses, available for super cheap on the used market, cover very well the full frame.
Though much more recent, i am not sure they would outperform good old film-era glasses.
Does anybody have personal experience, and made a quick comparison.
I am interested mainly in image quality, i know that the old F and FA lenses (albeit looking often wobbly) were of good mechanical quality, and personally i like to have a physical diaphragm ring, but now i'm jut curious to know if improved coatings and renewed optical projects actually improved image quality, even in economically priced lenses.

cheers

Paolo

Keep your two FA's.

The FA35 is better than the DA35 in many ways. The main difference is coating. This makes the DA 35 produce picture with very true colors, but really without any kind of interest.
Optical qualities are pretty much the same otherwise.

The FA 50 is a very fine piece of glass and like the DA35, the DA50 has nothing special that is worth getting it when you have the FA.

You will sell your FA's for the price of the DA, and you will only loose speed a tad. In the end, it's just a bad idea.

edit : the "outperforming sensor idea" is just a false idea. Your lens will resolve details very fine.
I had the chance to play with the Canon 5DsR and the old Canon 50mm f1.8 from the begining of the EOS mount. There is more details because there is more pixels, but that's pretty much it. Pictures came out exactly like on the 5Dii on every other things. the lens is no worse nor better than the new 50 1.8 STM.

[pathdoc]

I must admit that I reach for my DA50 in preference to the FA50 every time, except when I'm doing things with extension tubes that don't transmit aperture information or data, or when for some reason I just have to have a K-mount fast fifty on an older body (ME, MX, Ricoh XR-1). That's where the aperture ring comes in really handy. In addition, the FA50 is absolutely, positively, incontrovertibly full-frame-compatible (being designed in the film era), whereas there are some who will say that the DA gives vignetting at various apertures, distances, and bright backgrounds on full frame, which it does not give on APS-C.

I haven't noticed such vignetting on film, but this is possibly because the background was dark, I used flash which meant the auto-program was stopping down to somewhere between f/4 and f/8 (which might have masked or eliminated it), and I didn't take all that many shots to be able to be sure.

---------- Post added 01-12-16 at 12:47 ----------

I am not fond of the plastic bayonet

I wasn't either, but the DA50/1.8 changed my mind through experience. It's so short and light that there is no significant stress on the mount. Being a prime it doesn't have a zoom ring, while the focusing ring is light enough that the rotational torque is next to nothing when manual focusing.

When it comes to zoom lenses which protrude significantly, have a centre of gravity significantly clear of the camera body and have the torque stresses of the user working the zoom ring all the time, I would be less happy. I do admittedly have an FA28-90, but that's such a lightweight it isn't funny and it doesn't get used much; I have better lenses. Plus it cost me so little that if the mount ever breaks through overwork, I won't shed too many tears over it.

[stevebrot]

I don't know how the word "old" applies. Both FA lenses are current Pentax product and both are quite capable optics of modern design and construction. As far as DA equivalents for FF use on the K-1, I do not see any advantage to either of the "plastic fantastic" options, particularly if you already own the FA 35/2 and FA 50/1.4. I don't own a K-1, but was unimpressed with the DA 50/1.8 performance on 35mm film. It is a fun and capable lens for APS-C, but corner/edge performance and vignette are below that of my other fast 50s for the larger format.

I also don't own the DA 35/2.4 nor have I ever used one. The prevailing rumor is that it shares optics with the FA 35/2. I find that difficult to believe since the glass elements on the DA lens appear to be physically smaller in diameter. That aside, I can't comment directly about performance for the DA lens on FF. I can give an enthusiastic two-thumbs-up for the FA35/2 on 35mm film. The FA 35/2 was placed as a premium offering in the Pentax line-up when it debuted in 1999 (was significantly more expensive than the FA 50/1.4 even at that time) and is a very competent lens. Mine is always in the bag and often on the camera when I am shooting with my K-mount film SLRs and is my walk-around prime on the K-3.


Steve

[stevebrot]

I haven't noticed such vignetting on film, but this is possibly because the background was dark

That may be. The one time I shot with the DA 50/1.8 on film, part of the roll was a deliberate test that involved blank wall shots at f/1.8, f/2, f/2.8, f/4, f/5.6, and f/8. Obvious vignette was apparent by direct examination of the negative down to f/4. In general shooting, edge and corner performance was meh and not to the same standard as, say, my M 50/1.7.


Steve

[stevebrot]

Take a look at this Pentax 50mm Prime Lens Shootout Review - Introduction | PentaxForums.com Reviews it shows that hte 50 1.4 and the 50 1.8 are very evenly matched. Which is also my experience as well.

On APS-C, I would concur with the 2012 review. The DA 50/1.8 is a decent lens that punches well above its weight on the format for which it was designed. I have no hesitation using it on my K-3.


Steve

[pinholecam]

If I already have the 2 FA lenses (which I do), I won't look at the DA ones for FF use.

Even if they are the same optically, the DA versions are spec'ed for the APSC image circle.
This does mean that production lens tests and specs will properly take care of the FF image circle.
The result will be larger sample variation off center on FF.


Yes, there are sample shots with both DA lenses on FF.
But you need to question how often these have the subject off center (in the rule of thirds are at the least), and how good is the quality at those points.
Also, what about stopped down (ie. f8 and be there) type sames. (edge to edge sharpness being the criteria here)

Yes, if one already has the DA lenses, there is no harm trying them out on the K1.
Or if one can get them really cheap.
But the approach has to be one of 'fun' (of it works good on that copy -great) than spending good money in the hope that its a FA lens.

[cyberjunkie]

I don't know how the word "old" applies. Both FA lenses are current Pentax product and both are quite capable optics of modern design and construction. As far as DA equivalents for FF use on the K-1, I do not see any advantage to either of the "plastic fantastic" options, particularly if you already own the FA 35/2 and FA 50/1.4......

I used the word "old" because both are film-days lenses, and the 50mm, if i remember correctly, shares the same optics of the old Pentax-M version!
Not so strange though, i don't follow the evolutions in Canikon's lens offering, but i know that until quite recently both makers sold similar double-gauss 50mm "heritage lenses".
AFAIK the 35mm f/2 AL has a more modern design, and i know that many forum users were satisfied by its performance on APS-C sensors.
I didn't use much both FA lenses since the film times, i mainly do travel photography and especially the 35mm had no huge speed advantage over a good f/2.8 zoom.
Full frame opens a new door, and many lenses that were idling in a drawer will be given a new lease of life.
I'm looking forward to use them on my new K-1 as soon as i can.

The reason for my original post was the incredibly low price of a second hand DA 35mm AL or DA 50mm.
Both can be had for very cheap. I have seen a few being sold on Ebay for little more than 70 euros plus shipping, and often the lenses are spotless.
So i asked myself if it was worth to buy them and see myself how they would perform on FF.
From the responses i'm getting the answer seems to be NO.
Even if they cost less than some old glasses i routinely buy (that are nothing but collector's item!), it seems that the IQ isn't a step better than their FA counterparts.
While it is given that they are not better built, and somewhat slower.
I like to photograph at dusk and often at night, and i travel a lot, often storing the equipment in inconspicuous bags... which is not the best way to avoid knocks and bumps
All in all, i guess it's better to save the money for something else.

Thanks for your opinion, and for the very informative links.

EDIT:
The dynamics of the used lenses market are quite mysterious to me.
At least the two DA's were entry-level lenses...
I see old single-coated Takumars sold for way more than modern, SMC coated PK lenses.
The underlying logic is beyond my intelligence
It's not just Pentax-M 50mm's, often i see the very good Pentax-A 35-105mm and 70-210mm zooms sold for almost nothing.
If i had to explain why, i'd be at a loss.

cheers
Paolo

[pathdoc]

EDIT:
The dynamics of the used lenses market are quite mysterious to me.
At least the two DA's were entry-level lenses...
I see old single-coated Takumars sold for way more than modern, SMC coated PK lenses.
The underlying logic is beyond my intelligence
It's not just Pentax-M 50mm's, often i see the very good Pentax-A 35-105mm and 70-210mm zooms sold for almost nothing.
If i had to explain why, i'd be at a loss.

cheers
Paolo

It's mostly because of the rendering of the lens, not necessarily the sharpness. The Takumars are all metal and glass, and haev a very high build quality; many of the A lenses incorporate plastic parts. The sharpness of the A's and the resistance of flaring is better, but there is something subjective about the image quality of the earlier lenses that demands the higher price. Plus there are fewer of them remaining.

[Conqueror]

Keep the FA 35mm unless you plan to get an FA 31... and you should only consider that if you shot an awful lot at ~30 ~35

because the FA 35 is pretty decent and has the advantage of being compact/light weight