Re: The "wow" factor of slide film on a lightboxOn 20 Aug, 18:36, "Neil Gould" <n...@myplaceofwork . com > wrote:
> Recently, RolandRB <rolandbe...@hotmail . com > posted:
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> > On 20 Aug, 16:12, RolandRB <rolandbe...@hotmail . com > wrote:
> >> On 20 Aug, 14:39, RolandRB <rolandbe...@hotmail . com > wrote:
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> >>> On 20 Aug, 13:44, "David J. Littleboy" <davi...@gol . com > wrote:
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> >>>> "RolandRB" <rolandbe...@hotmail . com > wrote:
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> >>>>>>> This is the Sigma SD10 image:
> >>>>>>> * w w w .pbase . com /rolandrb/image/84194056/original
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> >>>>>>> This is the Sony DSC-R1 image:
> >>>>>>> * w w w .pbase . com /rolandrb/image/84194495
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> >>>>>> That's pretty badly sharpened to start with, but here ya go. 4MP
> >>>>>> of aliasing
> >>>>>> artifacts.
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> >>>> Look at slats on the windows on the next floor up on the building
> >>>> to the right of "Apotheke". In the original Sony image, the R1
> >>>> resolves those as equal-width slats, but the Sigma camera
> >>>> renders them as varying in width.
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> >>> I agree with that. The Sony does that better.
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> >>>> If you start looking around at the fine detail, you'll find lots
> >>>> more examples of detail that the Sony renders quite reasonably but
> >>>> which the Sigma either turns them randomness or fails to render at
> >>>> all. The Sigma loses it pretty badly on the roofs.
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> >>> I agree with that again but the Sony image looks bad even though it
> >>> is holding more details. There are a lot of distracting effects that
> >>> spoil the image. The rendering on the walls on the building behind
> >>> looks unreal rather than like a true texture. The rooves look
> >>> better, that is true, but maybe only because I have oversharpened.
> >>> If you look at the corner on the wall of the Sony image of the
> >>> building behind to the left of the TV mast then the Sony image
> >>> makes it look like there is a drainpipe running down the corner
> >>> edge when there is not. The lower roof of the rear building where
> >>> the bird is standing looks as though it had a black edge with a
> >>> white line on top. The people standing and sitting in front of the
> >>> Brötlibar restaurant look vague and unreal. They are too large and
> >>> their lack of detail is distracting. The foreground wall on the
> >>> right with the public seating in front has an unreal texture. The
> >>> "Tel 06" on the blue bin behind this wall does not show the "06"
> >>> clearly while the Sigma photo does. The six "BAR" red lettering in
> >>> the top windows below the "don't worry - be happy Bar" neon sign
> >>> look more like red curtain material in the Sony photo, though
> >>> downsized it looks better. The people sat below the "TicketCorner"
> >>> notice in the tram shelter look unclear. The people in the posters
> >>> to the left of the blue bin look unclear as do the real people in
> >>> front of the Rio Bar and the Zum Braunen Mutz. The Sony picture is
> >>> too big for the amount of detail it is showing and to me the image
> >>> looks bad. Printed out, it might look a bit better than the Sigma
> >>> photo, but to look at it on a computer screen then to me the Sigma
> >>> photo looks more like a print than the Sony photo does and is
> >>> easier on the eyes. It draws my view rather than repelling it.
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> >>> Perhaps if I could send you the Sony photo jpeg as it came out of
> >>> the camera and you did a careful downsizing then the downsized Sony
> >>> photo might look better. As you rightly said, the downsized Sony
> >>> photo was showing some horrendous artifacts in places, though I
> >>> thought overall it looked better.
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> >>>>>> * w w w .pbase . com /davidjl/image/84196441/original
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> >>>>> Thanks. Your fixed copy looks quite good to me. The writing is not
> >>>>> quite as distinct but that could be due to the exposure being
> >>>>> higher for the Sony image.
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> >>>> David J. Littleboy
> >>>> Tokyo, Japan- Hide quoted text -
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> >>> - Show quoted text -
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> >> I was looking at the slats next to the Apotheke building on the floor
> >> above. Today, looking at them, they were not regular. maybe the Sony
> >> was showing false details that human eyes would prefer to see and the
> >> Sigma was showing it more accurately. I will go back there now and
> >> photograph a more detailed image.- Hide quoted text -
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> >> - Show quoted text -
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> > Here are the slats as photographed today. The Sigma appears to have
> > done a better job at reproducing them than the Sony.
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> > * w w w .pbase . com /rolandrb/image/84205472
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> Very interesting, and just the kind of difference I would expect from a
> Bayer-pattern vs. Foveon comparison!
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> Neil- Hide quoted text -
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> - Show quoted text -
Me too but both methods have their strengths and weaknesses and both
methods are let down by the practicalities of using that method. A
Bayer 10.2 megapixel sensor should beat a Foveon 3.4x3 megapixel
sensor hands down in terms of its black & white resolution. The color
guessing should be a minor problem but would depend any case on the
interpolation software. The problem I see with using the Bayer pattern
is that an anti-aliasing filter is required to stop color Moiré
patterns. The Foveon sensor also has a regular array and so will
suffer Moiré patterns as well but less often and indeed, the Sigma
SD10 does not use an anti-aliasing filter. It is this introduced blur
of the anti-aliasing filter needed by the Bayer sensor that causes a
problem in that to undo the effects of the blur is not being handled
well in the software and perhaps it can't be. And where they try to
sharpen the blur then "unreal" detail come in that is annoying to look
at. But the the Foveon sensor has its faults as well. Colors are not
clearly distinct and two sensors can detect the same light freqeuncy
if the frequency falls between colors. Reds on the Foveon sensor are
not good because of this but then at the same time it gives a better
resolution for reds as red squares are only one quarter of the Bayer
pattern -- same as blue.
My own personal preference is that I want digital images to look good
on a computer monitor and to print the same. The Foveon sensor images
suit this although their colors can be misleading. It's a case of
"swings and roundabouts".