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10-24-2009, 01:20 AM   #1
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DA15 compensating for lack of versatility

being a fixed focal length lens, does the DA15 really lacks the versatility of that of the wide zoom lenses?

I know that the DA15 cannot compensate for shorter fl, but how about in the longer focal lengths area of the wide zoom lens from let's say 16mm to 24mm, where enlargement of the image and cropping is possible. can the cropping alone be enough or atleast be at par or even better than that of the zoom lens? let alone the fixed focal length lens at 20mm, 21mm, 24mm? focusing distance, exposure variations of course are being considered atleast to match the exposure equivalent, let alone the optimal sharpness of the image that can be achieved by the lens.

10-24-2009, 07:43 AM   #2
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Compared to the 12-24 there is big saving in weight and size with the 15. You will lose IQ when cropping for sure.

The DA15 is my grab and go lens and the 12-24 when I feel like carrying the extra weight for the flexibility of the zoom.
10-24-2009, 08:02 AM   #3
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I don't really think my 15LTD is much better than my 12-24 from an image quality perspective, but I can fit my 15 and 21 Limiteds in the same space as is taken up by the 12-24 and still have room for a nice pastrami sandwich.
The wide angle zooms seem to be such horses.
10-24-2009, 08:26 AM   #4
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QuoteOriginally posted by Wheatfield Quote
I don't really think my 15LTD is much better than my 12-24 from an image quality perspective, but I can fit my 15 and 21 Limiteds in the same space as is taken up by the 12-24 and still have room for a nice pastrami sandwich.
The wide angle zooms seem to be such horses.
I have the DA*16-50 that was as wide as I went before getting the DA15 limited but I didn't get the DA15 to go wider ...but rather smaller. In my DA* kit I would love to add a wide prime that I would prefer to a wide zoom. The 12-24 has an excellent reputation but I suspect if I owned it I would be using it at the wide end almost exclusively so why have a zoom. Same goes for the long end ..I had a sigma EX 100-300 and was using it as a 300 exclusively, so traded it to a DA*300 that is smaller lighter and I think has better IQ; not that the Sigma is any slouch in that regard.

10-24-2009, 08:44 AM   #5
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doubling of the focal length leads to double the magnification

so really, all you would need is the DA15, DA40, and a DA70

and really, have no need for a "zoom"

focal lengths between 10 and 15 provide for a very dramatic distortions and as such are not used often (atleast not used often after you shoot at 10 mm enough times and realize that the photos are just not quite right..so you stop )
10-24-2009, 08:48 AM   #6
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I'm always puzzled by people touting the versatility of zooms. In my opinion, you trade one kind of versatility for another. You gain versatility in quickly modifying perspective (not "zooming", because you can zoom with you feet most of the time), but you loose versatility when it comes to wide apertures (not the case with the DA15), taking shots with little distortion, shooting into the sun and perhaps most importantly, taking pictures unobtrusively.
Sometimes I want to have a battery grip, a hotshoe flash and a DA* zoom lens, for other times a couple of primes are more suited.

Also, as demonstrated in the photozone test, the DA15 is very sharp in the center, so cropping is also a valid option.
10-24-2009, 09:00 AM   #7
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When I use my 12-24 for urban/travel stuff I quite frequently zoom in to 21-24mm-ish focal lengths. As Gooshin mentioned, 12-15mm images tend to have severely distorted perspective (background objects look tiny), which is fun but not what I want for an entire slide show.

You lose resolution by cropping from the 15 -- whether this has any practical effect depends on the size of the print/screen image, the amount of detail present in the subject.

If you're just shooting images for viewing on your computer, you need a compact lens, and don't have time to change lenses, cropping from the 15 makes sense. It's not the best possible image, but probably good enough.
10-24-2009, 09:01 AM   #8
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I'm going to do some tests with some prime and zooms and see how they do with regards to real focal lens length and cropped/zoomed compensation for focal length.

I already did some previous tests before (35mm and 50mm) but I didn't do cropping enlargements for focal length simulation. as far as shooting at the same focusing length distance inorder to simulate or produce the same exact size of the image, the images looked great except that the FOV (background) of the other lens appears much wider.

this time I would only do cropping enlargements for the shorter lenses to compare it with the longer ones. criteria would be original size + IQ of longer lens versus cropped size and IQ of shorter lens. did anybody here did some tests like this? your inputs would be much appreciated in the discussion.


Last edited by Pentaxor; 10-24-2009 at 09:10 AM.
10-24-2009, 09:05 AM   #9
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QuoteOriginally posted by troyz Quote
When I use my 12-24 for urban/travel stuff I quite frequently zoom in to 21-24mm-ish focal lengths. As Gooshin mentioned, 12-15mm images tend to have severely distorted perspective (background objects look tiny), which is fun but not what I want for an entire slide show.

You lose resolution by cropping from the 15 -- whether this has any practical effect depends on the size of the print/screen image, the amount of detail present in the subject.

If you're just shooting images for viewing on your computer, you need a compact lens, and don't have time to change lenses, cropping from the 15 makes sense. It's not the best possible image, but probably good enough.
true. distortion is another thing to consider, but what about sharpness? sure there is a possibility that the resolution may not be up to it, especially in large prints but may not be evident nor appear significant enough to be noticed in smaller prints nor in a small monitor. this may appear though in a 40"-60" inch WIDE screen tv?
10-24-2009, 09:37 AM   #10
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QuoteOriginally posted by EricT Quote
I'm always puzzled by people touting the versatility of zooms. In my opinion, you trade one kind of versatility for another. You gain versatility in quickly modifying perspective (not "zooming", because you can zoom with you feet most of the time), but you loose versatility when it comes to wide apertures (not the case with the DA15), taking shots with little distortion, shooting into the sun and perhaps most importantly, taking pictures unobtrusively.
Not to mention the loss of versatility that comes if the zoom is so large you are loathe to take it with you in a given situation. Obviously not an issue for some people who don't mind carrying larger lenses, or who expect to use these kinds of wide angle lenses often enough to be worth taking up so much space in their bag with a wide zoom, but for many of us, it's a big deal. Luckily, both options exist, so everyone can be happy.

I have say, I agonized for quite a while between the DA15 and DA21. I knew a zoom was not for me, and I know I don't care about anything wider than 15mm, but I also realized that often I don't really want anything as wide as 15mm - I just want something wider than the 28mm that is currently my widest prime. I think a 17mm would have been the perfect prime for me, actually. For some reason, the thought of simply cropping shots from the DA15 didn't really pop into my head, except maybe once or twice in passing. But since I was also concerned that 21mm wouldn't be wide enough (I shoot the DA18-55 more often *at* 18mm than in the 18-21mm range), I went ahead and ordered the DA15 anyhow.

Even though my DA15 hasn't arrived yet, I had already been having occasional (just occasional!) flashes of buyers' remorse specifically over that issue - that 15mm was really wider than I wanted, and the lens might not get all that much use as a result. This thread is actually putting my mind much more at ease - I'm getting more and more excited about getting my DA15!
10-24-2009, 09:44 AM   #11
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QuoteOriginally posted by Marc Sabatella Quote
Not to mention the loss of versatility that comes if the zoom is so large you are loathe to take it with you in a given situation. Obviously not an issue for some people who don't mind carrying larger lenses, or who expect to use these kinds of wide angle lenses often enough to be worth taking up so much space in their bag with a wide zoom, but for many of us, it's a big deal. Luckily, both options exist, so everyone can be happy.

I have say, I agonized for quite a while between the DA15 and DA21. I knew a zoom was not for me, and I know I don't care about anything wider than 15mm, but I also realized that often I don't really want anything as wide as 15mm - I just want something wider than the 28mm that is currently my widest prime. I think a 17mm would have been the perfect prime for me, actually. For some reason, the thought of simply cropping shots from the DA15 didn't really pop into my head, except maybe once or twice in passing. But since I was also concerned that 21mm wouldn't be wide enough (I shoot the DA18-55 more often *at* 18mm than in the 18-21mm range), I went ahead and ordered the DA15 anyhow.

Even though my DA15 hasn't arrived yet, I had already been having occasional (just occasional!) flashes of buyers' remorse specifically over that issue - that 15mm was really wider than I wanted, and the lens might not get all that much use as a result. This thread is actually putting my mind much more at ease - I'm getting more and more excited about getting my DA15!
Marc, just in case your DA15 had arrived, maybe you could do some crop testing at the longer end? let's say about cropped to about 21-24mm equivalent of the image?
10-24-2009, 10:07 AM   #12
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QuoteOriginally posted by Pentaxor Quote
true. distortion is another thing to consider, but what about sharpness? sure there is a possibility that the resolution may not be up to it, especially in large prints but may not be evident nor appear significant enough to be noticed in smaller prints nor in a small monitor. this may appear though in a 40"-60" inch WIDE screen tv?
That's quite possible. Huge projections/prints require greater detail in the sensor image (and often greater depth of field) if the viewer has the opportunity to closely inspect the image.

However, if your humongous-screen TV has big pixels, then you will be limited by display resolution and not sensor resolution, and again the tight crop may appear to be about as good as the zoom lens image.

Your original post asks two questions:
Does the DA15 [+cropping] lack the versatility of a wide zoom?
IMHO, yes, but it might not make a difference for moderately cropped, small (web-size) images

can the cropping [from a prime] alone . . . be at par or even better than that of the zoom lens?
That depends on the the prime and the zoom and how tightly you crop. For the cropped DA15 versus the DA12-24@24mm, I'd bet on the 12-24 (unless the 12-24 picked up some flare or ghosting that the 15 didn't) but that's just a guess.

Last edited by troyz; 10-24-2009 at 10:12 AM.
10-24-2009, 10:32 AM   #13
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another reason why I started this thread is also in part of Marc's dilemma. obviously, for some people, size and weight does matter. people would love or prefer to have a compact wide lens like the DA15, especially for those trekkers. some people like the 12-24 or 10-20, etc... for the added much wider focal length end and closing up at 24mm. some would prefer a much balance and well-performing wide aperture opening of the zooms (the DA15 is great at the center resolution at wide open but only achieves it real potential and overall performance across the borders at f8 which is about 2 stops slower. having said that, the DA15 is excellent if we're not talking about aperture speed at wide open.
10-24-2009, 10:58 AM   #14
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QuoteOriginally posted by Marc Sabatella Quote
Not to mention the loss of versatility that comes if the zoom is so large you are loathe to take it with you in a given situation. Obviously not an issue for some people who don't mind carrying larger lenses, or who expect to use these kinds of wide angle lenses often enough to be worth taking up so much space in their bag with a wide zoom, but for many of us, it's a big deal. Luckily, both options exist, so everyone can be happy.

I have say, I agonized for quite a while between the DA15 and DA21. I knew a zoom was not for me, and I know I don't care about anything wider than 15mm, but I also realized that often I don't really want anything as wide as 15mm - I just want something wider than the 28mm that is currently my widest prime. I think a 17mm would have been the perfect prime for me, actually. For some reason, the thought of simply cropping shots from the DA15 didn't really pop into my head, except maybe once or twice in passing. But since I was also concerned that 21mm wouldn't be wide enough (I shoot the DA18-55 more often *at* 18mm than in the 18-21mm range), I went ahead and ordered the DA15 anyhow.

Even though my DA15 hasn't arrived yet, I had already been having occasional (just occasional!) flashes of buyers' remorse specifically over that issue - that 15mm was really wider than I wanted, and the lens might not get all that much use as a result. This thread is actually putting my mind much more at ease - I'm getting more and more excited about getting my DA15!
When I first got my K10D, I only had the kit lens, and most of my shots were at 18mm. Then I got the DA* 16-50mm, and suddenly most of my shots were at 16mm! I'm suspecting that if I get an ultra wide angle zoom, that I will still stay at the widest end. The DA15 ltd really appeals to me though...the biggest issue with my 16-50 is the distortion at the wide end and lack of flare resistance .
10-24-2009, 11:05 AM   #15
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QuoteOriginally posted by Pentaxor Quote
Marc, just in case your DA15 had arrived, maybe you could do some crop testing at the longer end? let's say about cropped to about 21-24mm equivalent of the image?
It comes Monday (although I might be out and miss it; not sure if I can or should get UPS to leave it anyhow, so it might be another day or two). Anyhow, sure, I'll do that, but aren't there full size samples all over the net you could use to do it yourself?

I know from experience with cropping in other contexts that, assuming the lens is not a complete dog, I'm personally almost always satisfied with results of cropping down to 1/2 the original dimensions (1/4 the original area) on my 10MP K200D. That reduces my image from 2592x3872 to 1296x1936, and virtually everything I do with my images is done with 1200x1800 JPEG's I generate from the original RAW files - it's the 1200x1800 JPEG I upload to Zenfolio/Flickr/etc, it's the 1200x1800 JPEG I send to family and friends when necessary. And when it comes to prints, a 1200x1800 JPEG is enough resolution for 300dpi at 4x6" (which is why I chose those dimensions for my JPEG's).

It's the very rare image that I need more resolution than this for - to print larger, or because I have a "client" who needs more resolution for their own prints. And pretty much every lens I have can withstand cropping down to 1/2 dimensions and still have acceptable quality to me - only my el-cheapo Samyang-made Vivitar 500/8 mirror gives me pause (but I'll still go there!). But aside that one one lens, I have to say that at full screen view or in 4x6" prints, I can barely tell the difference in sharpness between an image cropped to 1/2 the dimensions versus one shot with a longer lens. Given that the DA15 got about the best scores for center sharpness of any lens not named FA43 Limited, I have to believe it will work out at least as well for cropping as my other lenses.

This suggests that my DA15 could actually cover the entire range from 15-28 for me "most" of the time. Obviously not at the level of quality where I'll actually be likely to use the DA15 in place of my M28/2.8 in general, but I'm confident it will do everything I need in order to consider it a "15-21 digital zoom". Back of the envelope calculation here - seems like if cropping the image down to 1/2 dimensions yields an image with just enough pixels for my 1200x1800 JPEG's, and that's the equivalent of a 30mm lens (yes?), then to simulate a 21mm lens, I could keep at over 1600x2400 pixels, and that would be good for an 8x12" print at 200dpi. I'd still be generating those 1200x1800 JPEGs and using those for most purposes, but if I wanted to print 8x12", I don't think I'd be afraid to do so. If I expect to be hanging in art galleries, I might yet spring for the DA21 - but really, I'm not unhappy with the performance of my DA18-55II at that focal length, either.

Last edited by Marc Sabatella; 10-24-2009 at 11:12 AM.
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