[BruceBanner]

Indeed, this is one of the reasons it whops all of those legacy lenses, the K, the M, the A, the F series etc.

Do the FA Ltds beat it at F4 though?

IMO yep, quite substantially so. I did a test. Both of these shots I used the KP, one had the DA 20-40 set at 40mm f4, the other the FA43 at f4. Tripod was moved slightly to accommodate the focal length difference. Not much cropping gone on in either lens.



Concentrate on the bokeh, which version do you like more, can you guess which shot was taken with which lens?

[Jonathan Mac]

IMO yep, quite substantially so. I did a test. Both of these shots I used the KP, one had the DA 20-40 set at 40mm f4, the other the FA43 at f4. Tripod was moved slightly to accommodate the focal length difference. Not much cropping gone on in either lens.



Concentrate on the bokeh, which version do you like more, can you guess which shot was taken with which lens?

I see some differences but I can't claim to much prefer one over the other and the subject is equally sharp in both. Something in me tells me the one on the left is nicer, but it might just be the slight differences of where the shadows fall on the subject.

[BruceBanner]

I see some differences but I can't claim to much prefer one over the other and the subject is equally sharp in both. Something in me tells me the one on the left is nicer, but it might just be the slight differences of where the shadows fall on the subject.

So what we're not really doing here is comparing the actual duck that much. Both lenses at f4 are doing a great job in terms of sharpness (and of course there are subtle differences in where the light was falling between takes. What is a big difference however between the two shots is the bokeh. The bokeh on the image on the right is far more oof than on the left (the FA43 shot is on the right). In essence this is one of the optical properties that all the FA Ltds have over a lot of other glass, 'stopping down' when taking shots still renders bokeh similarly to when shooting at wider apertures. It's one of those things that I feel is not compared enough with on lens reviews. You can talk about the quality of bokeh but really direct comparisons can really be useful. Here we can see the FA43 really isolates the subject so much more and at the same f4 stop number as the 20-40.

A second example of the unique bokeh rendering capabilities of the FA Ltds can be seen in this post here; Hd fa35/2 - Page 3 - PentaxForums.com

If you look at the bokeh surrounding the jug (and comparing with the FA35) you can see the differences quite clearly. Whilst the FA35 starts to lose subject isolation as it is increasingly stopped down the FA31 continues to hold it for longer.

[Mbaez]

IMO yep, quite substantially so. I did a test. Both of these shots I used the KP, one had the DA 20-40 set at 40mm f4, the other the FA43 at f4. Tripod was moved slightly to accommodate the focal length difference. Not much cropping gone on in either lens.



Concentrate on the bokeh, which version do you like more, can you guess which shot was taken with which lens?

I like the one on the right.

[BruceBanner]

I like the one on the right.

Basically yeah

[Jonathan Mac]

So what we're not really doing here is comparing the actual duck that much. Both lenses at f4 are doing a great job in terms of sharpness (and of course there are subtle differences in where the light was falling between takes. What is a big difference however between the two shots is the bokeh. The bokeh on the image on the right is far more oof than on the left (the FA43 shot is on the right). In essence this is one of the optical properties that all the FA Ltds have over a lot of other glass, 'stopping down' when taking shots still renders bokeh similarly to when shooting at wider apertures. It's one of those things that I feel is not compared enough with on lens reviews. You can talk about the quality of bokeh but really direct comparisons can really be useful. Here we can see the FA43 really isolates the subject so much more and at the same f4 stop number as the 20-40.

A second example of the unique bokeh rendering capabilities of the FA Ltds can be seen in this post here; Hd fa35/2 - Page 3 - PentaxForums.com

If you look at the bokeh surrounding the jug (and comparing with the FA35) you can see the differences quite clearly. Whilst the FA35 starts to lose subject isolation as it is increasingly stopped down the FA31 continues to hold it for longer.

I think I'm missing something - f/4 at 40mm is always f/4 at 40mm (let's forget the extra 3mm of the Limited prime in this case). Given the same subject distance and sensor size, while the out-of-focus area may have different characteristics between lenses, the degree to which the background (or foreground) is out of focus at a given aperture will always be the same. f/4 is f/4 regardless of whether you need to stop down to get there or that's the maximum aperture of the lens in question.

[nocturnal]

F4 is wide open on DA20-40 Ltd so the aperture is a perfect circle with no blades forming a pattern which introduces a different kind of diffraction you get when stopping down on the FA 43 f1.9...

So 20-40 @ f4 @ 40mm has a perfecr circular aperture

and the FA 43 @ f4 has an octogal 8 sided aperture

[BruceBanner]

I think I'm missing something - f/4 at 40mm is always f/4 at 40mm (let's forget the extra 3mm of the Limited prime in this case). Given the same subject distance and sensor size, while the out-of-focus area may have different characteristics between lenses, the degree to which the background (or foreground) is out of focus at a given aperture will always be the same. f/4 is f/4 regardless of whether you need to stop down to get there or that's the maximum aperture of the lens in question.

What you're missing is the difference between a lens having more glass/elements than another, this can have quite a different impact on how the bokeh renders and appears (as well as I imagine other things such as grouping and placement of the elements). If you click on that other link I posted you can see a fair bit of difference between the FA31 and FA35 on how the bokeh resolves around the jug. (Hd fa35/2 - Page 3 - PentaxForums.com)

FA35, 6 elements, 5 groups
FA31, 9 elements, 7 groups

I have come to test and see for myself that the FA ltds seem to do a really nice job with how it handles bokeh. Those extra elements seem to account for a bokeh that you would normally associate from shooting at wider apertures, yet it's still able to put out that kinda look when stopped down. This is why these lenses are such a joy to use, you can shoot them a little more stopped down than wide open, gain the advantage of that (increased sharpness, more of the subject in focus) yet the compromise from bokeh that you would normally have to put up (from stopping down) does not quite apply the same. Really nice lenses for subject isolation, hence their preference for portraiture.

F4 is wide open on DA20-40 Ltd so the aperture is a perfect circle with no blades forming a pattern which introduces a different kind of diffraction you get when stopping down on the FA 43 f1.9...

So 20-40 @ f4 @ 40mm has a perfecr circular aperture

and the FA 43 @ f4 has an octogal 8 sided aperture

Correct, and that comes with pros and cons. On the one hand the 20-40 is giving nice circular bokeh at stopped down apertures, on the other hand the roundness of the blades leads to less than stella star bursts (if that's your thing). Having compared how a FA ltd renders star bursts I would say it quite substantially trumps the 20-40 in this regard.

It's not a competition tho, I mean I own both glass for a reason, the 20-40 is after all also WR, compact and silent AF, my biggest reasons for adding it to my collection. But hopefully the picture of the ducky above can help show people how different lenses do behave differently at the same apertures and approximate distance to subject (and the jug comparison shots are helpful also in the other thread).

One of my favourite shots that I think really shows the FA43 at its best is this shot I took here;



Obviously not comparing with a 20-40 here, how can it? This is a f1.9 shot and the 20-40 at 40mm would be f4. But what we're looking at here is how the bokeh is rendering. If we look at the wine glasses bottom left behind the girl the bokeh is layered, textured and rich. Having owned a DA50/1.8, FA50.1.4, DA40/2.8, I can honestly say that whilst those are great lenses and priced attractively with fantastic value to be had, the bokek for me was not resolving the same way. It was flatter and a little more... 'boring'.

The interesting thing about this shot is that even greater difference would have been seen had I stopped down to say f2.8, and then compared that with a DA40/2.8 or something, I think you will see how much more the subject appears isolated and the bokeh still retaining a more dreamy fade compared to a DA40/2.8 that starts to show that 'stopped down' look (similar to the jug examples).

Hope this helps! Sorry all for the slight deviation from the wonderful 20-40! Let's get back on track

[nocturnal]

Yes let's get back on track, that was a lengthy post

We've had the 20-40 starburst discussion before here DA Limited Zoom Club - Page 46 - PentaxForums.com

I proved the 20-40 Ltd with the photo posted that it does beautiful 18 point starbursts. The FA43 can only do 8 pointed stars which personally I don't like, a bit better than 6 points but for me that is a +1 for the 20-40. Pentax were clever to put 9 rounded blades in it for the bokeh and the ability to dial in starbursts with smaller apertures.

The FA Limiteds could be improved with HD coatings, 7 or 9 or any odd amount of rounded aperture blades with silent AF. They should have done this as they are very expensive new and are still making the original ones.

Thd FA31 in the UK costs more than £1000 new which is crazy for what is essentially a legacy lens albeit a classic.

[BruceBanner]

Yes let's get back on track, that was a lengthy post

We've had the 20-40 starburst discussion before here DA Limited Zoom Club - Page 46 - PentaxForums.com

I proved the 20-40 Ltd with the photo posted that it does beautiful 18 point starbursts. The FA43 can only do 8 pointed stars which personally I don't like, a bit better than 6 points but for me that is a +1 for the 20-40. Pentax were clever to put 9 rounded blades in it for the bokeh and the ability to dial in starbursts with smaller apertures.

The FA Limiteds could be improved with HD coatings, 7 or 9 or any odd amount of rounded aperture blades with silent AF. They should have done this as they are very expensive new and are still making the original ones.

Thd FA31 in the UK costs more than £1000 new which is crazy for what is essentially a legacy lens albeit a classic.

Yep, we have. I was pleased with the starburst from the DA 20-40, comparing my results from the HD DA 15 and 21 which I owned and didn't think did so well. It all depends on what you like with a starburst, the 20-40 is still 'mushy' compared to what I see as being cleaner defined points from the 43;

FA43 star burst examples;







HD DA 20-40 example;



It's no slouch, and arguably an unfair comparison as it is not stopped down the same as the shots from the FA43 above, but still perhaps someone will find those comparisons interesting.

I totally agree with you about the need for the FA ltds to see some upgrades, or at least a more fitting price tag. I think one of the reasons they are so high is they are all assembled by person individually? I dunno... but yeah the reason I don't own a FA31 (and maybe never will) is that insane price tag... very hard to justify. 20-40 is fantastic value

[nocturnal]

Yeah you need to stop it down more which is what I meant by dialling starbursts in to ones liking. Many times I don't want a star or sunburst.

Below is a sunburst at f11 which is where you need to be or smaller. I prefer these as they are a bit more faint, more subtle and not an over the top feature taking the centre stage. I don't like the SMC DA15 over the top starbursts and I have the HD version. The majority of times I don't want a spikey sun in my photographs which is one of the reasons I love the HD version instead.



Your FA43 Limited is great but I'm not a fan of those starbursts (although they work well as a feature in your first photo of the little tree, but for me as a landscaper 8 sunspikes look terrible), I suppose you could consider them as legacy starbursts, 8 bright spikes remind me of 80's photographs and those starburst filters, the cross type etc. As you agree to the need for updating the FA Limiteds, this is an area that could do with modernisation with 14 or 18 multiple and more subtle spikes? I'm sure the Pentax engineers consider this with new designs, although they rereleased the FA35 f2 with HD but left the legacy 6 straight blades in it which was a mistake IMHO.

Overall isn't it nice for us fo discuss the real qualitative qualities of lenses above the usual sharpness in corners, MTF charts, what lenstip says about it, internet site scores etc.

It's a real photographers discussion albeit still nerdy

[BruceBanner]

Yeah you need to stop it down more which is what I meant by dialling starbursts in to ones liking. Many times I don't want a star or sunburst.

Below is a sunburst at f11 which is where you need to be or smaller. I prefer these as they are a bit more faint, more subtle and not an over the top feature taking the centre stage. I don't like the SMC DA15 over the top starbursts and I have the HD version. The majority of times I don't want a spikey sun in my photographs which is one of the reasons I love the HD version instead.



Your FA43 Limited is great but I'm not a fan of those starbursts (although they work well as a feature in your first photo of the little tree, but for me as a landscaper 8 sunspikes look terrible), I suppose you could consider them as legacy starbursts, 8 bright spikes remind me of 80's photographs and those starburst filters, the cross type etc. As you agree to the need for updating the FA Limiteds, this is an area that could do with modernisation with 14 or 18 multiple and more subtle spikes? I'm sure the Pentax engineers consider this with new designs, although they rereleased the FA35 f2 with HD but left the legacy 6 straight blades in it which was a mistake IMHO.

Overall isn't it nice for us fo discuss the real qualitative qualities of lenses above the usual sharpness in corners, MTF charts, what lenstip says about it, internet site scores etc.

It's a real photographers discussion albeit still nerdy

Yep, and so personal choice also comes into the equation of what one likes from a lens in terms of star bursting and what not. Feel free to pass yer DA15 over to me

You're spot on the money though about the stuff that gets left out of a review. Most unique qualities of a lens happens at the wider apertures, even possibly entirely wide. A good example of this is the new DFA50/1.4, what it can do at f1.4 is unrivalled by any other glass for Pentax that is on the market to date. To hold edge sharpness at 1.4 is pretty insane. I've seen group portraits where f1.4 was used and having owned a FA50/1.4 I can tell you it's soft at 1.4 and even only in the centre.

But its more than just edge sharpness, it's about the bokeh, what does it look like, the quality etc, and for me in a review, without a comparison to another lens then the bokeh aspect is pretty hard to rate, however its actually one of the reasons the lens (any lens really) can cost so much! Once you get to f8 a lot of unique properties of a lens starts to fade away. We could for example take some 20-40 shots at 40mm and f8 against the FA43 at f8 and I bet plenty of mistakes will be made guessing which lens took which shot. However there will be no mistaking the FA43 at 1.9 and the 20-40 at f4 (is my point, or even like the duck pic a difference can be seen at f4 even).

So yeah, not enough bokeh comparisons for my liking (in reviews).

As you are more of a landscaper I can understand why you perhaps have not grabbed a FA ltd, I think much better value can be had elsewhere. And I think also they can CA quite badly. Picking the right tool for the job is important.

I don't mind the flare of the FA ltds (I try and use it for effect where possible) , HD coating might be cool, and I don't need more blades for star bursts as I'm ok with what they have. I agree with you about the FA35, star bursts from 6 straight blades is pretty bad, 8-9 blades is enough tho imo. What features I would want more would be WR and silent AF with Quickshift, optically I am fine with the recipe they came up with. I'd happily take a little more bulk in the lens for those features.

[onlineflyer]

Took the 20-40mm out for a walk today. Skies were showing some angry clouds but the colors were still eye catching. I don't shoot this lens often but it always brings out the best of the scene.

[onlineflyer]

And a few more

[onlineflyer]

And still a few more