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10-10-2010, 08:58 AM   #46
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QuoteOriginally posted by GeneV Quote
It seems like WallyB jumped all over me once for asking for that lens, but I think they ought to be able to make a reasonably compact 18mm 2.8 DA ltd. The kit zoom which is F3.5 at 18mm is not huge, and it seems like taking out the zoom and adding a bit more speed and IQ could yield a nice lens to hit that spot which would be about the size of the DA15.
wouldn't it be great....

10-10-2010, 10:06 AM   #47
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QuoteOriginally posted by GeneV Quote
It seems like WallyB jumped all over me once for asking for that lens, but I think they ought to be able to make a reasonably compact 18mm 2.8 DA ltd. The kit zoom which is F3.5 at 18mm is not huge, and it seems like taking out the zoom and adding a bit more speed and IQ could yield a nice lens to hit that spot which would be about the size of the DA15.
an 18mm lens with more speed at the size of the DA15? I'm just wondering how Pentax would do that.
10-10-2010, 10:19 AM   #48
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QuoteOriginally posted by axl Quote

the wide open performance of FA*24 is something that has kept me off the lens for a while. Now that I have it, I can conclude it's a myth or bollocks at best! This lens is just fine wide open. It's the same as 50/1.2. Many say it's soft, but the lens perfectly usable. And 24 is no different, when correctly focused the lens is great. Corner softness? Well you would expect it at 24mm and shallow f stops, so yes at f2-2.8 the corners are soft(er) but not horribly so. Still usable, and by corners I really mean corners (on APSC) I'm not fan of a brick wall tests but I think I'll have to do one to address this "badmouthing"

my 2p
Peter, what I meant by soft is the borders and corner shots that you were saying at f2 and f2.8. my use for such focal length requires solid rendering from corner to corner wide open (architectures and group shots). so anything that looks soft is unacceptable. the lens though sharpens up at f5.6 to those areas that I'm concerned with. but this is at f5.6 which makes no sense for a lens that is suppose to be good at faster aperture speed. that is why Pentax really needs to build a better lens, and at best, a lens with an opening of f2.4 or f2.8 with an excellent resolution across the image would be more of use to me rather than see uneven sharpness across the image.

as far as subject isolation is concerned or any lens that requires a fast opening for shallow DOF, a 28mm would be more a suitable or logical focal length for such use. if Pentax or the people that wanted Pentax to pursue a really fast 24mm for such use, I have no problems with it. but I will say that people should prepare to pay the ultimate price for such fast and excellent rendering.
10-10-2010, 10:58 AM   #49
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QuoteOriginally posted by Pentaxor Quote
Peter, what I meant by soft is the borders and corner shots that you were saying at f2 and f2.8. my use for such focal length requires solid rendering from corner to corner wide open (architectures and group shots). so anything that looks soft is unacceptable. the lens though sharpens up at f5.6 to those areas that I'm concerned with. but this is at f5.6 which makes no sense for a lens that is suppose to be good at faster aperture speed. that is why Pentax really needs to build a better lens, and at best, a lens with an opening of f2.4 or f2.8 with an excellent resolution across the image would be more of use to me rather than see uneven sharpness across the image.
personally I think it sharpens up nicely by f4 and I would not hesitate to shoot group of folks at f2.4/2.8. From my first few days with it, I'd say the lens is soft in extreme corners only, where with normal framing you wouldn't have people all that much anyway...

QuoteQuote:

as far as subject isolation is concerned or any lens that requires a fast opening for shallow DOF, a 28mm would be more a suitable or logical focal length for such use. if Pentax or the people that wanted Pentax to pursue a really fast 24mm for such use, I have no problems with it. but I will say that people should prepare to pay the ultimate price for such fast and excellent rendering.
I don't think 24/2 was ever about subject isolation. It was about shooting wide at dark... remember, that lens comes form era where 800 was considered high ISO and 1600 was like super high
Problem is that on film, 35/2 is/was very popular for few reasons: compact, moderate wide, great for landscapes, cityscapes, streets, people shots (capturing surroundings) etc..... f2 helped for sure with the isolation and shallower DOF but if you would really want isolate anything, you'd reach for your 50 or 85ish....
Now in modern days, mpx race is stalling, and ISO race is on! fast lenses are not as necessary as they were but from "artistic" POV, no supergood superhigh ISO will replace shallow(ish) DOF! And that's why many (myself including) demand fast(ish) lenses. APSC sensors don't help here and isolation gets even worse. 31/1.8 wide open is roughly 46/47 f2.4 in terms of DOF when compared to FF! So new DAL35/2.4 is only comparable to 50/3.2!!! and that is huge loss of DOF! So there we go with 24... @f2 on APSC it's only really comparable to 35/2.8 on FF, if they would make it even slower than they again loose huge amount of DOF!
I agree on the 28 statement, but by keeping 31ltd in the line up I think making 28 would be just stupidity, considering it would create:
28 - fast and expensive (probably DA*)
31 - fast and very expensive
35L - fast-ish cheap
35M - so so fast-ish and middle price
40 - as above

considering they have gaps between 21-31 and above 77 I really think 28 would make no sense.....

10-10-2010, 11:13 AM   #50
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QuoteOriginally posted by axl Quote
...
considering they have gaps between 21-31 and above 77 I really think 28 would make no sense.....
I agree, particularly since there are lots of really good 28mm lenses available on the used market at a reasonable price (including some that are autofocus). It is really difficult to find an excellent 24mm. Even the Zeiss 25mm is a bit weak in the corners (for a Zeiss). I used to own the A 24/2.8, and it was quite mediocre--not nearly as good any number of 28mm lenses that I own. (For example, the A 28/2 and the FA 28/2.8 are both much better in the corners than the 24, as are the K 30/2.8 and the FA Ltd 31.) The DA 21 is also much sharper in the corners than the A24, so it is not just a matter of it being easier to design a sharp lens at a longer focal length.

I think that a sharp 24mm with a maximum aperture of 2.4-2.8 would sell really well.

Dan
10-10-2010, 11:26 AM   #51
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QuoteOriginally posted by axl Quote


I don't think 24/2 was ever about subject isolation. It was about shooting wide at dark... remember, that lens comes form era where 800 was considered high ISO and 1600 was like super high
Problem is that on film, 35/2 is/was very popular for few reasons: compact, moderate wide, great for landscapes, cityscapes, streets, people shots (capturing surroundings) etc..... f2 helped for sure with the isolation and shallower DOF but if you would really want isolate anything, you'd reach for your 50 or 85ish....
Now in modern days, mpx race is stalling, and ISO race is on! fast lenses are not as necessary as they were but from "artistic" POV, no supergood superhigh ISO will replace shallow(ish) DOF! And that's why many (myself including) demand fast(ish) lenses. APSC sensors don't help here and isolation gets even worse. 31/1.8 wide open is roughly 46/47 f2.4 in terms of DOF when compared to FF! So new DAL35/2.4 is only comparable to 50/3.2!!! and that is huge loss of DOF! So there we go with 24... @f2 on APSC it's only really comparable to 35/2.8 on FF, if they would make it even slower than they again loose huge amount of DOF!
I agree on the 28 statement, but by keeping 31ltd in the line up I think making 28 would be just stupidity, considering it would create:
28 - fast and expensive (probably DA*)
31 - fast and very expensive
35L - fast-ish cheap
35M - so so fast-ish and middle price
40 - as above

considering they have gaps between 21-31 and above 77 I really think 28 would make no sense.....

the subject Isolation or shallow DOF at 24mm is only a reference I made for the other posters that said they want something like that like a portraiture wider lens. for me personally, I don't use a 24mm for such rendering due to the physical factors that affect DOF such as focal length magnification versus aperture speed versus equivalence. although the other brands are building their 24mm portraits by introducing an aperture with a 1.4 opening. but I doubt that it would be as good as something longer at 30,50, 70, and 85 with the same aperture speed.

a 28mm would make sense for someone who doesn't prefer a 31 but a 28mm focal length. or has a lens lineup of 15, 28, 35/40 or better yet 43/50. the difference between 31 and 35/40 doesn't appear that significant enough to keep in focal length terms. maybe for rendering but not of practicality when fl is concerned.
10-10-2010, 12:45 PM   #52
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Odd - i was just looking for a 24

I was looking for a 24, when i bought an F 28. f2.8. I use it but not quite satisfied with the FOV. I have a DA 21 which i'm using more these days. But you know the end to this story - what i really want is a 24.
Comments:
1. Do people want another $1000 prime lens - i don't think so.

2. If this plastic DA 35 f2.4 turns out to be good, i think a DA 24 along the same lines would be excellent. Keep it as cheap as possible but with Excellent IQ. f stop f2 to f2.8. Please - no WR - it just adds cost. screw drive because its cheaper. Plastic or built in hood, whichever is cheaper. Have i said cheaper to many times?

IMO

Last edited by philbaum; 10-10-2010 at 12:51 PM.
10-10-2010, 12:56 PM   #53
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QuoteOriginally posted by philbaum Quote
I was looking for a 24, when i bought an F 28. f2.8. I use it but not quite satisfied with the FOV. I have a DA 21 which i'm using more these days. But you know the end to this story - what i really want is a 24.
Comments:
1. Do people want another $1000 prime lens - i don't think so.

2. If this plastic DA 35 f2.4 turns out to be good, i think a DA 24 along the same lines would be excellent. Keep it as cheap as possible but with Excellent IQ. f stop f2 to f2.8. Please - no WR - it just adds cost. screw drive because its cheaper. Plastic or built in hood, whichever is cheaper. Have i said cheaper to many times?

IMO
Nope. cheaper is the magic word.

10-10-2010, 07:15 PM   #54
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QuoteOriginally posted by Pentaxor Quote
I would agree the necessity for a new 24mm prime, but an f2 prime at such focal length doesn't really give you that kind of special effect that you would want or like for a wide lens. that kind of subject isolation quality or kind of magic doesn't start until 28mm at fast aperture speed. for me a 24/2.8 would be the best solution rather than f2. it brings a balance between quality, compactness and cost altogether. since building an f2 wide angle lens would require more glass and lens length which would mean a glass selling no lower than $1,300 maybe even up to $1,500.
Where to start?

The bokeh difference between 24mm and 28mm is minimal. Even an experienced eye would be hard-pressed to tell the difference from a print with no "EXIF" data available.

The price range your suggesting is pure fantasy. Zeiss has a 25/2.8 and a 28/2 at about $1K (each weighing 1 pound and covering a full frame).

We're talking about an APS-C sized lens with a 24mm focal length at F2. This has advantages both in terms of size and cost that you're conveniently overlooking. Consider, for example, that the K 15mm 3.5 weighs in at 600g and is 80mm long whereas the DA15mm F4 weighs in at 212g and is 39.5mm long with a 49mm filter thread. Even allowing for the 1/3 stop difference in max aperture, you have to admit that there is a significant reduction in weight and size possible when designing a wide-angle lens for APS-C vs full-frame. And that HAS to bring the selling price below that of a full frame Zeiss!
10-10-2010, 08:39 PM   #55
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QuoteOriginally posted by Hello_Photo Quote
Where to start?

The bokeh difference between 24mm and 28mm is minimal. Even an experienced eye would be hard-pressed to tell the difference from a print with no "EXIF" data available.

The price range your suggesting is pure fantasy. Zeiss has a 25/2.8 and a 28/2 at about $1K (each weighing 1 pound and covering a full frame).

We're talking about an APS-C sized lens with a 24mm focal length at F2. This has advantages both in terms of size and cost that you're conveniently overlooking. Consider, for example, that the K 15mm 3.5 weighs in at 600g and is 80mm long whereas the DA15mm F4 weighs in at 212g and is 39.5mm long with a 49mm filter thread. Even allowing for the 1/3 stop difference in max aperture, you have to admit that there is a significant reduction in weight and size possible when designing a wide-angle lens for APS-C vs full-frame. And that HAS to bring the selling price below that of a full frame Zeiss!
that is exactly the point. the thing is, there was never a Pentax DA 24mm wide lens that had an f2 aperture speed. the DA15 that you mentioned is an F4 lens which costs over $600 on average and the DA21 which is slightly faster at f3.2 but isn't even better than the DA12-24, costs around $500. so if you will balance out the f2 aperture speed + excellent IQ, skipping the possibility of an f2.4 or f2.8 stops, surely you won't expect that Pentax would just add an additional $200 for skipping 1 and 1/3 aperture speed + an improved IQ, do you?

the price that I was referring to was if it were an FA LTD 24/2. a DA LTD 24/2 will be significantly cheaper but will still cost over a $1,000.

don't get me wrong, I would love to have a cheaper, fast 24mm with excellent IQ, but the economic situation of those companies doesn't seem to permit that.
10-10-2010, 09:17 PM   #56
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QuoteOriginally posted by Pentaxor Quote
that is exactly the point. the thing is, there was never a Pentax DA 24mm wide lens that had an f2 aperture speed. the DA15 that you mentioned is an F4 lens which costs over $600 on average and the DA21 which is slightly faster at f3.2 but isn't even better than the DA12-24, costs around $500. so if you will balance out the f2 aperture speed + excellent IQ, skipping the possibility of an f2.4 or f2.8 stops, surely you won't expect that Pentax would just add an additional $200 for skipping 1 and 1/3 aperture speed + an improved IQ, do you?
Sure I do. All I have to do is accept that a DA 24/2 would be larger than the DA 21 pancake. In exchange, I would get the improved IQ and larger aperture. Simple. Note, that this would also differentiate a DA24/2 within the Pentax lens line-up. Those who prefer compactness and slightly wider angle would still line-up for the DA21 and others (like myself) that are willing to accept a slightly larger lens in exchange for a larger max aperture would pick the DA24/2. We already see this in the DA70 vs FA77, both of which are still produced by Pentax.
10-11-2010, 06:34 AM   #57
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QuoteOriginally posted by Pentaxor Quote
an 18mm lens with more speed at the size of the DA15? I'm just wondering how Pentax would do that.
Wally, you are back!

I'm not an engineer, but just looking at the lenses around that FL it seems like it should be possible. The DA15 is a bit shorter than the Kit lens, but almost the same diameter and weight. The DA15 is also slower than the kit lens at 18mm but significantly wider FOV. It seems to me that a fixed focus lens could be made smaller than the kit zoom at the same FL, even if it were a bit faster--maybe not all the way to 2.8. Also, the A 20 2.8 was just a little bigger than the DA15 and it covered full frame.

Last edited by GeneV; 10-11-2010 at 06:44 AM.
10-20-2010, 11:20 AM   #58
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Sony Distagon T* 24mm F2 SSM Lens Review: 1. Introduction: Digital Photography Review

Canon, Nikon and Sony have them, I want a Pentax 24mm lens. 24/2 is just as good as 24/1.4, I just want a good one from Pentax.
10-21-2010, 02:51 PM   #59
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QuoteOriginally posted by rover Quote
Sony Distagon T* 24mm F2 SSM Lens Review: 1. Introduction: Digital Photography Review

Canon, Nikon and Sony have them, I want a Pentax 24mm lens. 24/2 is just as good as 24/1.4, I just want a good one from Pentax.
Price
US: $1250
UK: 1100
EUR: 1250

i wonder how many people will buy it or would buy something in k-mount in this price tag... it weights 555g, what is more than sigma 24/1.8 (485g), and not much smaller. and almost triple sigma price... and sigma's only real downside is the size... for f/2 you even have to close it a bit...
10-21-2010, 03:01 PM   #60
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QuoteOriginally posted by jane7l Quote
Price
US: $1250
UK: 1100
EUR: 1250

i wonder how many people will buy it or would buy something in k-mount in this price tag... it weights 555g, what is more than sigma 24/1.8 (485g), and not much smaller. and almost triple sigma price... and sigma's only real downside is the size... for f/2 you even have to close it a bit...
Canon, Nikon, Sony and Zeiss are FF lenses! If Pentax would make DA24 APSC only they could save a bit and sell it under 1k in whichever of those currencies IMO
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