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09-28-2011, 06:37 PM   #31
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QuoteOriginally posted by s.randy Quote
When I originally made this thread the Sigma 20 f1.8 was the last lens that I saw before I went off. When it comes to wider angled lenses I wouldn't be as picky in reality 3.2 is plenty, its the DA70 f2.4 that irks me mainly, that one should be f1.4 instead!! That would be so awesome but then again it'd be a grand at least for it probably
And it would be a brick also. There are tradeoffs if you're making small, compact lenses that aren't very expensive. This is even more true when you're talking about pancakes like the 21 and 40. You can't have everything in one package.

Why not buy a FA77 or FA85? Both are faster than the DA70.

09-28-2011, 06:56 PM   #32
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QuoteOriginally posted by abacus07 Quote
And it would be a brick also. There are tradeoffs if you're making small, compact lenses that aren't very expensive. This is even more true when you're talking about pancakes like the 21 and 40. You can't have everything in one package.

Why not buy a FA77 or FA85? Both are faster than the DA70.
Yeah those are both good options, the FA85 is discontinued so dealing with finding a good used copy would be a pain and I'd probably have to rent both the DA70 and FA77 before I picked one over the other, 1.8 isnt a whole lot faster than 2.4 and the DA70 is half the price.

Reality is I'm not even trying to buy anything right now which actually makes things worse because day dreaming takes over. If I actually had money I would know what I need and it wouldn't matter as much I guess I'm just whining because I don't actually need anything.
09-28-2011, 07:07 PM   #33
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QuoteOriginally posted by s.randy Quote
Yeah those are both good options, the FA85 is discontinued so dealing with finding a good used copy would be a pain and I'd probably have to rent both the DA70 and FA77 before I picked one over the other, 1.8 isnt a whole lot faster than 2.4 and the DA70 is half the price.

Reality is I'm not even trying to buy anything right now which actually makes things worse because day dreaming takes over. If I actually had money I would know what I need and it wouldn't matter as much I guess I'm just whining because I don't actually need anything.
While I agree about the price, the FA77 is almost a full stop faster. that's hardly insignificant. And this kind of comes full circle to the comments regarding Pentax making light, relatively inexpensive lenses with outstanding IQ. If you make the lens fast like you want it's no longer small (important to some) and it is more expensive. There are tradeoffs involved. If you want a great, fast lens then be prepared to ante up. Unless of course you go MF. Samyang is making some outstanding options that are fast.
09-28-2011, 07:12 PM   #34
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I had the same thoughts when I started to look for a 24-28mm prime.
But when I got a K24/2.8 I began to realize the thought process behind the DA21, which is pretty sound.
Shallow DOF is less important on wide angle lens. Neither does one shoot wide open that often with one.
Stopped down a little up to f4, for human subjects between head and shoulders to half body, there is still enough separation between subject and bkgnd.
In fact, coupled with the nice sharpness and contrast of Pentax lenses like the K24 and FA*24, there is often a nice 3D effect with right lighting.


So DA21 as a good walk about focal length was made with the concept of being portable, low encumbrance, with a trade off of being a bit slow, but usable right from f3.2 and will still give some DOF subject separation and a nice 'pop'.


In general, smaller lenses and cameras is what makes them unique.

09-28-2011, 07:14 PM   #35
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QuoteOriginally posted by abacus07 Quote
While I agree about the price, the FA77 is almost a full stop faster. that's hardly insignificant. And this kind of comes full circle to the comments regarding Pentax making light, relatively inexpensive lenses with outstanding IQ. If you make the lens fast like you want it's no longer small (important to some) and it is more expensive. There are tradeoffs involved. If you want a great, fast lens then be prepared to ante up. Unless of course you go MF. Samyang is making some outstanding options that are fast.
I totally agree with you, my problem is loving shallow DOF way to much, I do have an old trusty M 50mm f1.7, so when I feel like my DA40 isn't fast enough I play with that for a bit

On that note I'm not totally opposed to MF
09-28-2011, 07:16 PM   #36
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QuoteOriginally posted by pinholecam Quote
I had the same thoughts when I started to look for a 24-28mm prime.
But when I got a K24/2.8 I began to realize the thought process behind the DA21, which is pretty sound.
Shallow DOF is less important on wide angle lens. Neither does one shoot wide open that often with one.
Stopped down a little up to f4, for human subjects between head and shoulders to half body, there is still enough separation between subject and bkgnd.
In fact, coupled with the nice sharpness and contrast of Pentax lenses like the K24 and FA*24, there is often a nice 3D effect with right lighting.


So DA21 as a good walk about focal length was made with the concept of being portable, low encumbrance, with a trade off of being a bit slow, but usable right from f3.2 and will still give some DOF subject separation and a nice 'pop'.


In general, smaller lenses and cameras is what makes them unique.
Yeah that size makes a big difference, when I shoot my DA40 for long periods of time then throw on the M 50 f1.7 it feels so heavy
09-29-2011, 12:48 AM   #37
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QuoteOriginally posted by s.randy Quote
why the hell doesn't Pentax make faster lenses??
If you can live with manual focus lenses (which can sometimes be an advantage at wide open) have a look at some of the older Pentax legacy lenses.

Myself, I still use Pentax A series lenses in my working day and as you can see from my sig, several are within your aperture requirements.

Last edited by Kerrowdown; 09-29-2011 at 12:54 AM.
09-29-2011, 01:27 AM   #38
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Well i'm one of the people that has the Sigma 28mm f1.8, and have used it for the last 18mo. The good: at 1.8-2.4 it has a sharp center to softish edges. The bad: it has massive fild curvature(you can actually focus the edge and have the center go OOF)and it never gets completly sharp over the frame(and it's worse on FF as I had the same lens for the Nikon D3X). it is an entirely underwhelming lens, and the 35 F2.4 is worlds more satisfying. BUT in the 1.8(which the K5-7 exif says is 1.7) to 2.4 range for low light is's pretty good, with the above taken into account, but I expect the FA31 to blow it away when it gets here.

David

09-29-2011, 02:14 AM   #39
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It would be great if Pentax released some new fast primes. Hopefully the Ricoh announcement in a few days may bring some good news

In the meantime the FA*85 has a high chance of being my next lens purchase....
09-29-2011, 02:27 AM   #40
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QuoteOriginally posted by kerrowdown Quote
If you can live with manual focus lenses (which can sometimes be an advantage at wide open) have a look at some of the older Pentax legacy lenses.
And if that's not affordable, well, my brilliant-sharp Vivitar-Komine 28/2 CFWA (close-focus wide-angle) cost under US$20 (shipped) a few months ago. Some amazing good glass can still be found cheap. I hope.
09-29-2011, 03:20 AM   #41
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QuoteOriginally posted by s.randy Quote
Sigmas 20mm is 1.8 the DA21 is 3.2 C'mon
the point is that the Sigma weight 500gr, where the Pentax weight 140gr.

You can't have a lense that is "light twice"
09-29-2011, 04:32 AM   #42
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QuoteOriginally posted by steve1307 Quote
There is no "Sigma f1.8 wide prime pumps my 'nads " thread in the lens club section is there?
No offence to other thread creators but maybe we do not have such Sigma threads because Sigma owners are reasonable?

My Sigma 28/1.8 EX is one of the best lenses I have. And with its close focusing ability it is also one of my most versatile. It is very sharp and can produce very nice bokeh. Not quite an FA 31/1.8 but you can get it for a fraction of the price.

However, I don't create a "Sigma f1.8 wide prime pumps my 'nads " thread.

QuoteOriginally posted by steve1307 Quote
These 3 Sigmas f1.8 are far less popular than the "slower" manufacturer options which are f2.8. they are also less popular than the hyper expensive 24mm f1.4's which Cinon & Nakon produce.
Popularity is not always the best measure for quality.

Many just don't like the size of the lenses and/or want to avoid larger filter sizes. If you want fast glass without too much vignetting, however, there is no way around increasing the diameter of the front element.

Hey, you even have people on this forum that suggest not to get a Pentax DSLR if you are into birding or sports despite the fact that Sigma/Tamron offer great long glass for the K-mount.

QuoteOriginally posted by steve1307 Quote
Could it be that they are crap until about f3.2 anyway, they are massive and plasticky and the 77 or 82mm filters cost a bomb?
Could be, yes, but no they are not crap until about f3.2.

Isn't it great that we have the choice between excellent, fast Sigma glass and competent, compact Pentax glass? Why assume / argue that one of the manufacturers does something wrong?

P.S.: Photozone obviously tested a defective copy of the Sigma 20/1.8. Not sure what the measurements are worth.
09-29-2011, 06:13 AM   #43
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QuoteOriginally posted by Reportage Quote
Quality and price consumers willing to pay?

by all accounts the DA 35mm f/2.4 could have been a f/1.8 or f/2.0 but rather then release a lens that is not acceptable sharp at f/1.8, they released it at f/2.4 instead.

Think of it, does anyone actually have a FA50mm f/1.4 that is sharp at f/1.4?

The main problem when wide open, is the dof is so shallow that its easy to miss the focus. Slight shifts in body movement I've noticed can affect it. Even with (some would say, because of) AF. It's for that reason I chose an older A lens. Cause, as a lot of reviews seem to confirm, many times the AF doesn't work or is so slow, which negates the reason to have it in the 1st place.
09-29-2011, 12:17 PM   #44
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QuoteOriginally posted by TOUGEFC Quote
In the meantime the FA*85 has a high chance of being my next lens purchase....
It is truly great, I love it. But I don't often use it wide open. Perhaps if I bought DA70, I'd use it more as it is small and light...

QuoteOriginally posted by Class A Quote
Photozone obviously tested a defective copy of the Sigma 20/1.8. Not sure what the measurements are worth.
I trust you on that 28mm is very good. But 24mm is already clearly inferior to FA*24 (I shot a lot with both lenses) and from what I heard the 20mm sigma is the least good of the three. And the guy that sold me the optically near perfect FA*24 replaced it with DA21. He just wanted smaller lens.
09-29-2011, 01:08 PM   #45
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I own a Sigma 20mm f/1.8 on my Pentax k-x, and i start immediately saying that i'm trying to sell it.

this lens have few but nice pros
-the 0.2m focus distance
-f/1.8
-nice manual focus ring
-nice construction

now we come with the cons .-.
-soft
- edges
-very easy flare
-and the one i hate most... size/weight

Now, I can easily tolerate the optical quality since the 1.8 aperture, but the reason because I use this lens very little is the bulk, the feature that I most underestimated at the purchase.

some example...
f/8, this is the maximum sharpness this lens can offer
f/1.8 bokeh
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