I've heard a lot about how the cropped sensor cameras are defraction limited to around f/8 - f/11, so I thought I'd see what kind of an image my XSi puts out at a small aperture.
I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, with a shutter speed of 1 sec.
> I've heard a lot about how the cropped sensor cameras are defraction > limited to around f/8 - f/11, so I thought I'd see what kind of an image > my XSi puts out at a small aperture.
> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, > with a shutter speed of 1 sec.
Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I loathe), so there could be some diffraction visible, but I'm also not convinced that the subject didn't move within the 1 second exposure!
>> I've heard a lot about how the cropped sensor cameras are defraction >> limited to around f/8 - f/11, so I thought I'd see what kind of an image >> my XSi puts out at a small aperture.
>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, >> with a shutter speed of 1 sec.
> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I > loathe), so there could be some diffraction visible, but I'm also not > convinced that the subject didn't move within the 1 second exposure!
> Cheers, > David
Thanks, David, I'll try it again with an inanimate object, or a faster shutter speed.
I suppose, if the test is to be useful, I should also take an equivalent pic of the subject using a wider aperture so the two images can be compared.
> Thanks, David, I'll try it again with an inanimate object, or a faster > shutter speed.
> I suppose, if the test is to be useful, I should also take an equivalent > pic of the subject using a wider aperture so the two images can be > compared.
> Take Care, > Dudley
Indeed, yes. Tripod and very careful focussing come to mind. While the degradation due to diffraction at f/22 is noticeable with careful inspection, you probably wouldn't notice with normal use - just sharpen a little more. Diffraction on small sensor cameras is one reason why some of them are limited to f/8 or f/11 as the smallest aperture.
> "Dudley Hanks" <dha...@blind-apertures.ca> wrote in message > news:DvaIm.50463$Db2.1880@edtnps83... > [] >> Thanks, David, I'll try it again with an inanimate object, or a faster >> shutter speed.
>> I suppose, if the test is to be useful, I should also take an >> equivalent pic of the subject using a wider aperture so the two images >> can be compared.
>> Take Care, >> Dudley
> Indeed, yes. Tripod and very careful focussing come to mind. While the > degradation due to diffraction at f/22 is noticeable with careful > inspection, you probably wouldn't notice with normal use - just sharpen > a little more. Diffraction on small sensor cameras is one reason why > some of them are limited to f/8 or f/11 as the smallest aperture.
Some of them haven't even got diaphragm and the "diaphragm" is simulated with a neutral filter.
> I've heard a lot about how the cropped sensor cameras are defraction limited > to around f/8 - f/11, so I thought I'd see what kind of an image my XSi puts > out at a small aperture.
> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, > with a shutter speed of 1 sec.
>>> I've heard a lot about how the cropped sensor cameras are defraction >>> limited to around f/8 - f/11, so I thought I'd see what kind of an image >>> my XSi puts out at a small aperture.
>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, >>> with a shutter speed of 1 sec.
>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >> loathe), so there could be some diffraction visible, but I'm also not >> convinced that the subject didn't move within the 1 second exposure!
>> Cheers, >> David > Thanks, David, I'll try it again with an inanimate object, or a faster > shutter speed. > I suppose, if the test is to be useful, I should also take an equivalent pic > of the subject using a wider aperture so the two images can be compared.
The diffraction limit of aperture is usually taken to be the last aperture in a decreasing series of sharper apertures, i.e., stopping down further makes the image softer because of diffraction. But that's not a fixed aperture, it depends on such things as the exact sensor pixel size (or crop factor) not just the nominal "1.5", on the resolution of the lens, and whether you're looking at the centre of the image or the edges or some compromise between the two. Why should it depend on those? Because the point at which an extra stop's worth of diffraction softening becomes larger than how much other kinds of lens aberration are being improved by stopping down obviously will depend on the size of those other errors. In other words better lenses will have larger sharpest apertures.
I find for example on my Sony A350 that my general purpose zoom is usually sharpest at f8, but at its soft extremes that becomes f11, and my 50mm prime is sharpest at f5.6.
This can only be established for your camera and each of your lenses by taking a comparative series of shots while varying the aperture. On zooms it may change with focal length.
>>>> I've heard a lot about how the cropped sensor cameras are defraction >>>> limited to around f/8 - f/11, so I thought I'd see what kind of an >>>> image >>>> my XSi puts out at a small aperture.
>>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at >>>> f/22, >>>> with a shutter speed of 1 sec.
>>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >>> loathe), so there could be some diffraction visible, but I'm also not >>> convinced that the subject didn't move within the 1 second exposure!
>>> Cheers, >>> David
>> Thanks, David, I'll try it again with an inanimate object, or a faster >> shutter speed.
>> I suppose, if the test is to be useful, I should also take an equivalent >> pic >> of the subject using a wider aperture so the two images can be compared.
> The diffraction limit of aperture is usually taken to be the last > aperture in a decreasing series of sharper apertures, i.e., stopping > down further makes the image softer because of diffraction. But that's > not a fixed aperture, it depends on such things as the exact sensor > pixel size (or crop factor) not just the nominal "1.5", on the > resolution of the lens, and whether you're looking at the centre of > the image or the edges or some compromise between the two. Why > should it depend on those? Because the point at which an extra stop's > worth of diffraction softening becomes larger than how much other > kinds of lens aberration are being improved by stopping down obviously > will depend on the size of those other errors. In other words better > lenses will have larger sharpest apertures.
> I find for example on my Sony A350 that my general purpose zoom is > usually sharpest at f8, but at its soft extremes that becomes f11, and > my 50mm prime is sharpest at f5.6.
> This can only be established for your camera and each of your lenses > by taking a comparative series of shots while varying the aperture. On > zooms it may change with focal length.
> -- > Chris Malcolm
Thanks, Chris, that's good info to have.
This is a pretty cheap lens, and I think its a bit soft to begin with.
I've always been a fan of mildly soft portraits, and this lens has worked well for that purpose. But its also given me a few nice and sharp pics as well.
It'll be interesting to see how it performs across its full range...
>>>> I've heard a lot about how the cropped sensor cameras are defraction >>>> limited to around f/8 - f/11, so I thought I'd see what kind of an image >>>> my XSi puts out at a small aperture.
>>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, >>>> with a shutter speed of 1 sec.
>>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >>> loathe), so there could be some diffraction visible, but I'm also not >>> convinced that the subject didn't move within the 1 second exposure!
>>> Cheers, >>> David
>> Thanks, David, I'll try it again with an inanimate object, or a faster >> shutter speed.
>> I suppose, if the test is to be useful, I should also take an equivalent pic >> of the subject using a wider aperture so the two images can be compared.
>The diffraction limit of aperture is usually taken to be the last >aperture in a decreasing series of sharper apertures, i.e., stopping >down further makes the image softer because of diffraction. But that's >not a fixed aperture, it depends on such things as the exact sensor >pixel size (or crop factor) not just the nominal "1.5", on the >resolution of the lens, and whether you're looking at the centre of >the image or the edges or some compromise between the two. Why >should it depend on those? Because the point at which an extra stop's >worth of diffraction softening becomes larger than how much other >kinds of lens aberration are being improved by stopping down obviously >will depend on the size of those other errors. In other words better >lenses will have larger sharpest apertures.
>I find for example on my Sony A350 that my general purpose zoom is >usually sharpest at f8, but at its soft extremes that becomes f11, and >my 50mm prime is sharpest at f5.6.
>This can only be established for your camera and each of your lenses >by taking a comparative series of shots while varying the aperture. On >zooms it may change with focal length.
Your test won't work. Unless the widest aperture of your lens is the very sharpest, that means that the lens is not of diffraction-limited quality, the very best there is. If you lose detail at any time that you open up the lens, then that means the lens is not diffraction-limited. If it's not diffraction limited you can't tell when diffraction is what is causing the softening. As in all DSLR glass, the softening you see is due to lenses not being of diffraction-limited quality, poor lens manufacturing. Usually only one stop is adequate because the defects are overridden by that particular aperture stop. Anything above and below it is showing lens-figure defects, not diffraction problems.
Better Info <bi...@address.info> wrote: > On 4 Nov 2009 17:49:36 GMT, Chris Malcolm <c...@holyrood.ed.ac.uk> wrote: >>The diffraction limit of aperture is usually taken to be the last >>aperture in a decreasing series of sharper apertures, i.e., stopping >>down further makes the image softer because of diffraction. But that's >>not a fixed aperture, it depends on such things as the exact sensor >>pixel size (or crop factor) not just the nominal "1.5", on the >>resolution of the lens, and whether you're looking at the centre of >>the image or the edges or some compromise between the two. Why >>should it depend on those? Because the point at which an extra stop's >>worth of diffraction softening becomes larger than how much other >>kinds of lens aberration are being improved by stopping down obviously >>will depend on the size of those other errors. In other words better >>lenses will have larger sharpest apertures.
>>I find for example on my Sony A350 that my general purpose zoom is >>usually sharpest at f8, but at its soft extremes that becomes f11, and >>my 50mm prime is sharpest at f5.6.
>>This can only be established for your camera and each of your lenses >>by taking a comparative series of shots while varying the aperture. On >>zooms it may change with focal length. > Your test won't work. Unless the widest aperture of your lens is the very > sharpest, that means that the lens is not of diffraction-limited quality, > the very best there is. If you lose detail at any time that you open up the > lens, then that means the lens is not diffraction-limited.
You've got it back to front. Since diffraction increases as the lens is stopped because because of the change of proportion of lens area to lens circumference, the test works for all cases EXCEPT when the widest aperture is sharpest.
> If it's not > diffraction limited you can't tell when diffraction is what is causing the > softening. As in all DSLR glass, the softening you see is due to lenses not > being of diffraction-limited quality, poor lens manufacturing.
That's true when the aperture is wider than the diffraction limited aperture, and false when it's smaller. The point you're missing is that lens aberrations reduce as the lens stops down, because a higher proportion of the image is coming from less refracted parts of the lens, but as you stop down the proportion of diffraction increases, because the diffraction proportion is related to the area/circumference proportion of the aperture. So in any non-diffraction-limited lens there will be an aperture where the improving of lens defects by stopping down is overtaken by the worsening of diffraction effects.
On 5 Nov 2009 02:02:28 GMT, Chris Malcolm <c...@holyrood.ed.ac.uk> wrote:
>You've got it back to front. Since diffraction increases as the lens >is stopped because because of the change of proportion of lens area to >lens circumference, the test works for all cases EXCEPT when the >widest aperture is sharpest.
Go educate your useless fuck of an ignorant moron troll self. Resolution increases with objective optics diameter. IF those optics are of diffraction limited quality.
Dudley Hanks wrote: > I've heard a lot about how the cropped sensor cameras are defraction limited > to around f/8 - f/11, so I thought I'd see what kind of an image my XSi puts > out at a small aperture.
> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, > with a shutter speed of 1 sec.
> How did it turn out?
The only way to know is to do a test in series. It looks soft to me. Sometimes that's OK though, sometimes DOF is more important. This photo: http://www.flickr.com/photos/edgehill/4075980407 had DOF as a priority though I didn't exceed the diffraction limits and the lens is near optimum wide open. The power lines in the upper left are soft due to tilting the focus plane.
>>> "David J Taylor" >>> <david-tay...@blueyonder.not-this-bit.nor-this.co.uk.invalid> wrote in >>> message news:t6aIm.1501$Ym4.551@text.news.virginmedia.com... >>>> "Dudley Hanks" <> wrote in message >>>> news:4U9Im.50459$Db2.29545@edtnps83... >>>>> I've heard a lot about how the cropped sensor cameras are defraction >>>>> limited to around f/8 - f/11, so I thought I'd see what kind of an >>>>> image >>>>> my XSi puts out at a small aperture.
>>>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at >>>>> f/22, >>>>> with a shutter speed of 1 sec.
>>>>> Take Care, >>>>> Dudley >>>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >>>> loathe), so there could be some diffraction visible, but I'm also not >>>> convinced that the subject didn't move within the 1 second exposure!
>>>> Cheers, >>>> David >>> Thanks, David, I'll try it again with an inanimate object, or a faster >>> shutter speed. >>> I suppose, if the test is to be useful, I should also take an equivalent >>> pic >>> of the subject using a wider aperture so the two images can be compared. >> The diffraction limit of aperture is usually taken to be the last >> aperture in a decreasing series of sharper apertures, i.e., stopping >> down further makes the image softer because of diffraction. But that's >> not a fixed aperture, it depends on such things as the exact sensor >> pixel size (or crop factor) not just the nominal "1.5", on the >> resolution of the lens, and whether you're looking at the centre of >> the image or the edges or some compromise between the two. Why >> should it depend on those? Because the point at which an extra stop's >> worth of diffraction softening becomes larger than how much other >> kinds of lens aberration are being improved by stopping down obviously >> will depend on the size of those other errors. In other words better >> lenses will have larger sharpest apertures.
>> I find for example on my Sony A350 that my general purpose zoom is >> usually sharpest at f8, but at its soft extremes that becomes f11, and >> my 50mm prime is sharpest at f5.6.
>> This can only be established for your camera and each of your lenses >> by taking a comparative series of shots while varying the aperture. On >> zooms it may change with focal length.
>> -- >> Chris Malcolm
> Thanks, Chris, that's good info to have.
> This is a pretty cheap lens, and I think its a bit soft to begin with.
The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a lot of excellent shots with mine, so please don't sell it short! I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an improvement as you might expect from the price difference.
-- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^---------------------------------------------------------------
>>> "David J Taylor" >>> <david-tay...@blueyonder.not-this-bit.nor-this.co.uk.invalid> wrote in >>> message news:t6aIm.1501$Ym4.551@text.news.virginmedia.com... >>>> "Dudley Hanks" <> wrote in message news:4U9Im.50459$Db2.29545@edtnps83... >>>>> I've heard a lot about how the cropped sensor cameras are defraction >>>>> limited to around f/8 - f/11, so I thought I'd see what kind of an image >>>>> my XSi puts out at a small aperture.
>>>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, >>>>> with a shutter speed of 1 sec.
>>>>> Take Care, >>>>> Dudley >>>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >>>> loathe), so there could be some diffraction visible, but I'm also not >>>> convinced that the subject didn't move within the 1 second exposure!
>>>> Cheers, >>>> David >>> Thanks, David, I'll try it again with an inanimate object, or a faster >>> shutter speed. >>> I suppose, if the test is to be useful, I should also take an equivalent pic >>> of the subject using a wider aperture so the two images can be compared. >> The diffraction limit of aperture is usually taken to be the last >> aperture in a decreasing series of sharper apertures, i.e., stopping >> down further makes the image softer because of diffraction. But that's >> not a fixed aperture, it depends on such things as the exact sensor >> pixel size (or crop factor) not just the nominal "1.5", on the >> resolution of the lens, and whether you're looking at the centre of >> the image or the edges or some compromise between the two. Why >> should it depend on those? Because the point at which an extra stop's >> worth of diffraction softening becomes larger than how much other >> kinds of lens aberration are being improved by stopping down obviously >> will depend on the size of those other errors. In other words better >> lenses will have larger sharpest apertures.
>> I find for example on my Sony A350 that my general purpose zoom is >> usually sharpest at f8, but at its soft extremes that becomes f11, and >> my 50mm prime is sharpest at f5.6.
>> This can only be established for your camera and each of your lenses >> by taking a comparative series of shots while varying the aperture. On >> zooms it may change with focal length.
> Your test won't work.
Please, get back to us when you grow a clue. Bye!
-- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^---------------------------------------------------------------
Dudley Hanks wrote: > I've heard a lot about how the cropped sensor cameras are defraction limited > to around f/8 - f/11, so I thought I'd see what kind of an image my XSi puts > out at a small aperture.
> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, > with a shutter speed of 1 sec.
I'll go farther than previous respondents: That photo, from a Canon XSi at f/22, is obviously not diffraction limited.
The statements you'll hear of the diffraction limit assume everything else it practically optimal: rock-steady subject, tripod mount, perfect focus, and unless the claim is about a particular lens, they mean a laudably sharp one.
Dudley Hanks wrote: > "David J Taylor" > <david-tay...@blueyonder.not-this-bit.nor-this.co.uk.invalid> wrote in > message news:t6aIm.1501$Ym4.551@text.news.virginmedia.com... >> "Dudley Hanks" <> wrote in message news:4U9Im.50459$Db2.29545@edtnps83... >>> I've heard a lot about how the cropped sensor cameras are defraction >>> limited to around f/8 - f/11, so I thought I'd see what kind of an image >>> my XSi puts out at a small aperture.
>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, >>> with a shutter speed of 1 sec.
>>> Take Care, >>> Dudley >> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >> loathe), so there could be some diffraction visible, but I'm also not >> convinced that the subject didn't move within the 1 second exposure!
> Thanks, David, I'll try it again with an inanimate object, or a faster > shutter speed.
> I suppose, if the test is to be useful, I should also take an equivalent pic > of the subject using a wider aperture so the two images can be compared.
If you are serious about being able to tell include a few ball bearings on black velvet in the picture composition. Specular highlights are about the easiest thing to see if an image is diffraction limited.
Or you could just use a pinhole over the lens and a verry long exposure.
> Dudley Hanks wrote: >> "Chris Malcolm" <c...@holyrood.ed.ac.uk> wrote in message >> news:7ldt5gF3cimtaU1@mid.individual.net... >>> Dudley Hanks <dha...@blind-apertures.ca> wrote:
>>>> "David J Taylor" >>>> <david-tay...@blueyonder.not-this-bit.nor-this.co.uk.invalid> wrote in >>>> message news:t6aIm.1501$Ym4.551@text.news.virginmedia.com... >>>>> "Dudley Hanks" <> wrote in message >>>>> news:4U9Im.50459$Db2.29545@edtnps83... >>>>>> I've heard a lot about how the cropped sensor cameras are defraction >>>>>> limited to around f/8 - f/11, so I thought I'd see what kind of an >>>>>> image >>>>>> my XSi puts out at a small aperture.
>>>>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at >>>>>> f/22, >>>>>> with a shutter speed of 1 sec.
>>>>>> Take Care, >>>>>> Dudley >>>>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >>>>> loathe), so there could be some diffraction visible, but I'm also not >>>>> convinced that the subject didn't move within the 1 second exposure!
>>>>> Cheers, >>>>> David >>>> Thanks, David, I'll try it again with an inanimate object, or a faster >>>> shutter speed. >>>> I suppose, if the test is to be useful, I should also take an >>>> equivalent pic >>>> of the subject using a wider aperture so the two images can be >>>> compared. >>> The diffraction limit of aperture is usually taken to be the last >>> aperture in a decreasing series of sharper apertures, i.e., stopping >>> down further makes the image softer because of diffraction. But that's >>> not a fixed aperture, it depends on such things as the exact sensor >>> pixel size (or crop factor) not just the nominal "1.5", on the >>> resolution of the lens, and whether you're looking at the centre of >>> the image or the edges or some compromise between the two. Why >>> should it depend on those? Because the point at which an extra stop's >>> worth of diffraction softening becomes larger than how much other >>> kinds of lens aberration are being improved by stopping down obviously >>> will depend on the size of those other errors. In other words better >>> lenses will have larger sharpest apertures.
>>> I find for example on my Sony A350 that my general purpose zoom is >>> usually sharpest at f8, but at its soft extremes that becomes f11, and >>> my 50mm prime is sharpest at f5.6.
>>> This can only be established for your camera and each of your lenses >>> by taking a comparative series of shots while varying the aperture. On >>> zooms it may change with focal length.
>>> -- >>> Chris Malcolm
>> Thanks, Chris, that's good info to have.
>> This is a pretty cheap lens, and I think its a bit soft to begin with.
> The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a > lot of excellent shots with mine, so please don't sell it short! > I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an > improvement as you might expect from the price difference.
Originally, I bought it for my Canon A2, but didn't use it a lot. I used it a bit for blurred background shots of the kids, flowers, etc.
However, with the crop factor of the XSi, it's now a great portrait lens, and it still has a fairly respectable aperture when I add in my 2x converter, giving me a (35mm equiv) f/3.5 160mm lens.
I'm finding myself falling back on it a lot these days.
On Thu, 05 Nov 2009 23:39:40 +1000, Bob Larter <bobbylar...@gmail.com> wrote in <4af2c78...@dnews.tpgi.com.au>:
>The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a >lot of excellent shots with mine, so please don't sell it short! >I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an >improvement as you might expect from the price difference.
What you get for the money with the f/1.4 over the f/1.8 is speed, not IQ.
-- Best regards, John
Buying a dSLR doesn't make you a photographer, it makes you a dSLR owner. "The single most important component of a camera is the twelve inches behind it." -Ansel Adams
>>>> "David J Taylor" >>>> <david-tay...@blueyonder.not-this-bit.nor-this.co.uk.invalid> wrote in >>>> message news:t6aIm.1501$Ym4.551@text.news.virginmedia.com... >>>>> "Dudley Hanks" <> wrote in message news:4U9Im.50459$Db2.29545@edtnps83... >>>>>> I've heard a lot about how the cropped sensor cameras are defraction >>>>>> limited to around f/8 - f/11, so I thought I'd see what kind of an image >>>>>> my XSi puts out at a small aperture.
>>>>>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, >>>>>> with a shutter speed of 1 sec.
>>>>>> Take Care, >>>>>> Dudley >>>>> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I >>>>> loathe), so there could be some diffraction visible, but I'm also not >>>>> convinced that the subject didn't move within the 1 second exposure!
>>>>> Cheers, >>>>> David >>>> Thanks, David, I'll try it again with an inanimate object, or a faster >>>> shutter speed. >>>> I suppose, if the test is to be useful, I should also take an equivalent pic >>>> of the subject using a wider aperture so the two images can be compared. >>> The diffraction limit of aperture is usually taken to be the last >>> aperture in a decreasing series of sharper apertures, i.e., stopping >>> down further makes the image softer because of diffraction. But that's >>> not a fixed aperture, it depends on such things as the exact sensor >>> pixel size (or crop factor) not just the nominal "1.5", on the >>> resolution of the lens, and whether you're looking at the centre of >>> the image or the edges or some compromise between the two. Why >>> should it depend on those? Because the point at which an extra stop's >>> worth of diffraction softening becomes larger than how much other >>> kinds of lens aberration are being improved by stopping down obviously >>> will depend on the size of those other errors. In other words better >>> lenses will have larger sharpest apertures.
>>> I find for example on my Sony A350 that my general purpose zoom is >>> usually sharpest at f8, but at its soft extremes that becomes f11, and >>> my 50mm prime is sharpest at f5.6.
>>> This can only be established for your camera and each of your lenses >>> by taking a comparative series of shots while varying the aperture. On >>> zooms it may change with focal length.
>> Your test won't work.
>Please, get back to us when you grow a clue. Bye!
Bob Larter's legal name: Lionel Lauer Home news-group, an actual group in the "troll-tracker" hierarchy: alt.kook.lionel-lauer (established on, or before, 2004) Registered Description: "the 'owner of several troll domains' needs a group where he'll stay on topic."
John Navas wrote: > On Thu, 05 Nov 2009 23:39:40 +1000, Bob Larter <bobbylar...@gmail.com> > wrote in <4af2c78...@dnews.tpgi.com.au>:
>> The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a >> lot of excellent shots with mine, so please don't sell it short! >> I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an >> improvement as you might expect from the price difference.
> What you get for the money with the f/1.4 over the f/1.8 is speed, > not IQ.
The f1.4 also has more aperture blades, so the bokeh is a bit nicer as well.
-- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^---------------------------------------------------------------
On Fri, 06 Nov 2009 11:56:53 +1000, Bob Larter <bobbylar...@gmail.com> wrote:
>John Navas wrote: >> On Thu, 05 Nov 2009 23:39:40 +1000, Bob Larter <bobbylar...@gmail.com> >> wrote in <4af2c78...@dnews.tpgi.com.au>:
>>> The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a >>> lot of excellent shots with mine, so please don't sell it short! >>> I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an >>> improvement as you might expect from the price difference.
>> What you get for the money with the f/1.4 over the f/1.8 is speed, >> not IQ.
>The f1.4 also has more aperture blades, so the bokeh is a bit nicer as well.
Post-processing plugins with depth-map masks afford an infinite number of aperture blades for bokeh, as well as even emulating catadioptric lens systems no matter what camera took the image, and more.
Educationg Trolls Is An Endless Task <eti...@somewhere.net> wrote:
> On 5 Nov 2009 02:02:28 GMT, Chris Malcolm <c...@holyrood.ed.ac.uk> wrote: >>You've got it back to front. Since diffraction increases as the lens >>is stopped because because of the change of proportion of lens area to >>lens circumference, the test works for all cases EXCEPT when the >>widest aperture is sharpest. > Go educate your useless fuck of an ignorant moron troll self. Resolution > increases with objective optics diameter. IF those optics are of > diffraction limited quality.
But as you keep pointing out, DSLR lenses are not of diffraction limited quality and we're discussing DSLR lenses here!
If you actually uderstood what you're talking about you'd realise that that makes half your comments in this thread nonsense. You're arguing two logically incompatible positions at the same time.
Is the amount of swearing and cursing you do when trying to educate others a reflection of how your own teachers treated you when they they were trying to teach you? :-)
> John Navas wrote: >> On Thu, 05 Nov 2009 23:39:40 +1000, Bob Larter <bobbylar...@gmail.com> >> wrote in <4af2c78...@dnews.tpgi.com.au>:
>>> The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a >>> lot of excellent shots with mine, so please don't sell it short! >>> I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an >>> improvement as you might expect from the price difference.
>> What you get for the money with the f/1.4 over the f/1.8 is speed, not >> IQ.
> The f1.4 also has more aperture blades, so the bokeh is a bit nicer as > well.
> -- > W > . | ,. w , "Some people are alive only because > \|/ \|/ it is illegal to kill them." Perna condita delenda est > ---^----^---------------------------------------------------------------
On 6 Nov 2009 02:51:17 GMT, Chris Malcolm <c...@holyrood.ed.ac.uk> wrote:
>Educationg Trolls Is An Endless Task <eti...@somewhere.net> wrote: >> On 5 Nov 2009 02:02:28 GMT, Chris Malcolm <c...@holyrood.ed.ac.uk> wrote:
>>>You've got it back to front. Since diffraction increases as the lens >>>is stopped because because of the change of proportion of lens area to >>>lens circumference, the test works for all cases EXCEPT when the >>>widest aperture is sharpest.
>> Go educate your useless fuck of an ignorant moron troll self. Resolution >> increases with objective optics diameter. IF those optics are of >> diffraction limited quality.
>But as you keep pointing out, DSLR lenses are not of diffraction >limited quality and we're discussing DSLR lenses here!
What part of; that's exactly why you can't determine what aperture reveals diffraction being an imaging problem because your lenses are not figured accurately enough to cause observable diffraction, it's all optics figure error; do you fail to comprehend?
Time to go educate your useless troll-ass of a self.
>If you actually uderstood what you're talking about you'd realise that >that makes half your comments in this thread nonsense. You're arguing >two logically incompatible positions at the same time.
>Is the amount of swearing and cursing you do when trying to educate >others a reflection of how your own teachers treated you when they >they were trying to teach you? :-)
I'll leave you to your fuckingly pathetic trolls' ignorance, only for you to wake up one day (or not) realizing just how amazingly stupid you were with your words and reasoning on this day. Just another day of many thousands where you have done exactly the same. Garbage in, garbage out.
>On Fri, 06 Nov 2009 11:56:53 +1000, Bob Larter <bobbylar...@gmail.com> >wrote:
>>John Navas wrote: >>> On Thu, 05 Nov 2009 23:39:40 +1000, Bob Larter <bobbylar...@gmail.com> >>> wrote in <4af2c78...@dnews.tpgi.com.au>:
>>>> The 50mm/F1.8II is a surprisingly good lens for the money. I've taken a >>>> lot of excellent shots with mine, so please don't sell it short! >>>> I've since 'upgraded' to a 50mm/F1.4, but it's not as much of an >>>> improvement as you might expect from the price difference.
>>> What you get for the money with the f/1.4 over the f/1.8 is speed, >>> not IQ.
>>The f1.4 also has more aperture blades, so the bokeh is a bit nicer as well.
>Post-processing plugins with depth-map masks afford an infinite number of
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