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Can't believe someone would say this with a straight face

 
 
Rob
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      08-27-2012
On 27/08/2012 10:45 AM, Trevor wrote:
> "David J. Littleboy" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
>> FWIW, I find 6x7 (56 x 70 mm) film scanned on a Nikon 9000 very close to
>> what I see from the 21MP 5DII. With a good lens at f/8, the 5DII is
>> friggin amazing. It's competing with over four times the area of film

>
> My experience too, and the D800 is even better, and then there is medium
> format digital!
>
>
>>> Comparing 35mm to 8x10 is rather stupid.

>
>> Well, not necessarily. In real life, 4x5 and 8x10 shooters shoot at f/32
>> and f/45 a lot, at which point the resolution on the film isn't as good as
>> 6x7 shot at f/8.

>
> That would support my claim it is stupid to compare. However I dispute your
> claim that the resolution of an 8"x10" film shot with a high quality large
> format lens at f32 is less than 6x7cm film at f8. *IF* you tried to use the
> same lens perhaps! Otherwise you're dreaming.
> Remember you need a longer lens for larger formats at the same angle of
> view, and the aperture does not cause the same diffraction effects until it
> is correspondingly smaller.
>
>
>> In landscape work, the large format users go after scenes with incredible
>> amounts of detail; in the landscape magazines here, the LF work jumps off
>> the page at one. But the resolution on the page isn't adequate for even
>> digital.

>
> Agreed, there is no benefit of using LF for small size prints like
> magazines. The situation changes somewhat if you try to do a large mural
> using a 35mm camera!
> (you might do pano and stitch these days of course)
> You certainly don't see many pictures being taken on 8x10" any more, it's
> pretty hard to justify the cost of film for no real benefit. And the cost of
> LF digital backs is rather prohibitive atm!
>
> Trevor.
>
>
>
>



My take on this is a MF and LF have a better feel to the picture and are
more acceptable than a stitched DX or FX digital. Its not necessarily
more resolution its prospective. A 90 degree coverage with a 90mm lens
makes a nice image.

Yes my digital camera is high Mp and the only way to cover a scene for
me is long lens and stitch, then lots of post processing to take out the
distortion and make it flat. This is my way of recreating the feel of MF
and LF.
 
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Trevor
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      08-27-2012

"Rob" <(E-Mail Removed)> wrote in message
news:k1ehfg$fip$(E-Mail Removed)...
>> Agreed, there is no benefit of using LF for small size prints like
>> magazines. The situation changes somewhat if you try to do a large mural
>> using a 35mm camera!
>> (you might do pano and stitch these days of course)
>> You certainly don't see many pictures being taken on 8x10" any more, it's
>> pretty hard to justify the cost of film for no real benefit. And the cost
>> of
>> LF digital backs is rather prohibitive atm!
>>

>
> My take on this is a MF and LF have a better feel to the picture and are
> more acceptable than a stitched DX or FX digital.


Everyone is entitled to a preference without justification.

>Its not necessarily more resolution its prospective.


"Prospective" ?

>A 90 degree coverage with a 90mm lens makes a nice image.


The lens focal lenth/angle of view/perspective is only relative to the
film/sensor size. A 90mm lens on a 35mm camera is less than 30deg, and
simply using a 21mm lens will give you approx 90deg coverage.


> Yes my digital camera is high Mp and the only way to cover a scene for me
> is long lens and stitch, then lots of post processing to take out the
> distortion and make it flat. This is my way of recreating the feel of MF
> and LF.


For what purpose though?

Actually few 8x10" photos are taken with lenses equivalent to 90mm on a 35mm
camera (which of course is less than 90deg). If you meant 90mm on an 8x10
camera, that's still not as common as something like a 135mm or more. But
whatever choices work for you are all that matters, to you, surely?

Trevor.


 
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Bruce
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      08-28-2012
"Neil Ellwood" <(E-Mail Removed)> wrote:

>Ric Trexell wrote:
>
>>
>> "Savageduck" <savageduck1@{REMOVESPAM}me.com> wrote in message
>> news:201208250105017987-savageduck1@REMOVESPAMmecom... >On
>> 2012-08-25 06:12:28 -0700, Alfred Molon <(E-Mail Removed)> said:
>> >
>> > > In article <(E-Mail Removed)> , Ric
>> > > Trexell says...
>> > > > Digital does not have the range of film. I think it
>> > > > can only show something like 40 shades of black and white while
>> > > > film can record over a hundred.
>> > >
>> > > That's very strange, because most DLSRs easily have a range of 11
>> > > stops, which should be way more than 100 shades of grey (although
>> > > it's not clear what you mean with "shades"). In addition you can
>> > > use HDR to extend the range and some cameras have inbuilt DSLR.
>> >
>> > You might want to rephrase your last few words.
>> >
>> >
>> > -- Regards,
>> >
>> > Savageduck

>> __________________________________________________ ________________
>>
>> Savageduck: I wasn't talking about f/stops, but by shades I meant
>> that if you took a picture of 100 swabs of paint (used as an example)
>> the first one consisting of 100 parts white, then the next having 99
>> parts white and 1 part black, and repeated this until at the end of
>> the board you had 100 parts black, the digital would see about 40
>> different shades of gray where as film would see more. For someone
>> like me with what I call shade blindness, that is in tests my former
>> employer gave me of 20 different shades of red-blue, I would only see
>> about 15 it doesn't really matter. Part of the reason I said former
>> employer is that I was employed as a printer, and when they asked me
>> if I noticed these two colors were off, I would say...they are? Ric.

>
>Surely that would be 101 shADES.



But aren't there 50 shades of grey?


 
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Martin Brown
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      08-28-2012
On 25/08/2012 15:42, Ric Trexell wrote:
> "Savageduck" <savageduck1@{REMOVESPAM}me.com> wrote in message
> news:201208250105017987-savageduck1@REMOVESPAMmecom...
>> On 2012-08-25 06:12:28 -0700, Alfred Molon <(E-Mail Removed)> said:
>>
>>> In article <(E-Mail Removed)> , Ric
>>> Trexell says...
>>>> Digital does not have the range of film. I think it
>>>> can only show something like 40 shades of black and white while film can
>>>> record over a hundred.


It is hard to imagine how you can be so totally wrong about both digital
and film systems simultaneously.

>>> That's very strange, because most DLSRs easily have a range of 11 stops,
>>> which should be way more than 100 shades of grey (although it's not
>>> clear what you mean with "shades"). In addition you can use HDR to
>>> extend the range and some cameras have inbuilt DSLR.

>>
>> You might want to rephrase your last few words.


Consumer digicams are typically limited to 12 bits linear better kit is
14 bits and the high end cooled astronomical CCDs are at least 16 bits
and fully quantitative over the entire dynamic range provided that the
wells do not actually overflow (leading to a whole row burning out).

> Savageduck: I wasn't talking about f/stops, but by shades I meant that if
> you took a picture of 100 swabs of paint (used as an example) the first one
> consisting of 100 parts white, then the next having 99 parts white and 1
> part black, and repeated this until at the end of the board you had 100
> parts black, the digital would see about 40 different shades of gray where
> as film would see more. For someone like me with what I call shade
> blindness, that is in tests my former employer gave me of 20 different
> shades of red-blue, I would only see about 15 it doesn't really matter.


Paint on a card or paper is just about the worst possible test case. You
cannot make an adequate photometric black that way nor an acceptable
white. The dynamic range is severely limited by scattered light from the
target and not by any intrinsic defect of the imaging system or sensor.

Xray film by transmitted light has more dynamic range than normal film
can cope with and will challenge a 16 bit linear system to capture both
extremes of shadow detail and highlights (subject to original correct
exposure).

> Part of the reason I said former employer is that I was employed as a
> printer, and when they asked me if I noticed these two colors were off, I
> would say...they are? Ric.


Being colour blind and working in a colour printshop must be something
of a handicap. At least electronic engineers can measure resistors when
they cannot read the colour bar codes reliably.

It is actually quite hard to distinguish more than about 100 shades of
pure grey on print media because of surface scattered and reflected
light. Even the very best matt pigments on paper are pathetic blacks
when compared to the inside of a ball lined with black velvet.

--
Regards,
Martin Brown
 
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Doug McDonald
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      08-28-2012
On 8/28/2012 1:49 PM, Martin Brown wrote:

> It is actually quite hard to distinguish more than about 100 shades of pure grey on print media
> because of surface scattered and reflected light. Even the very best matt pigments on paper are
> pathetic blacks when compared to the inside of a ball lined with black velvet.
>


The best blacks on prints are on the glossiest papers, properly
lit with a single spot light at an angle. Some papers can get
well over 1000:1 contrast ratio. Of course, that assumes an
otherwise black room for background. The results using prints
so lit with brightness at or approaching sunlight are simply stunning.

I sometime made prints for that express purpose. This requires
a whole recalibration of one's mental "Zone System", especially
what Zones 0, 1, 2, 8, 9 and 10 mean. And so far I have not found
ink-jet prints that are dark enough in the blacks to equal
either B&W or color chemical prints.

Doug McDonald
 
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Martin Brown
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      08-29-2012
On 28/08/2012 22:49, Doug McDonald wrote:
> On 8/28/2012 1:49 PM, Martin Brown wrote:
>
>> It is actually quite hard to distinguish more than about 100 shades of
>> pure grey on print media
>> because of surface scattered and reflected light. Even the very best
>> matt pigments on paper are
>> pathetic blacks when compared to the inside of a ball lined with black
>> velvet.

>
> The best blacks on prints are on the glossiest papers, properly
> lit with a single spot light at an angle. Some papers can get
> well over 1000:1 contrast ratio. Of course, that assumes an
> otherwise black room for background. The results using prints
> so lit with brightness at or approaching sunlight are simply stunning.


I'd give it more like 500:1 but that is with a black velvet sheet as a
target for the front surface reflection. On ordinary print media even in
glossy magazines you seldom see anything like 100:1.

I use this trick for photographing old archive material that is too
fragile to flatbed scan in situ side lit at an angle so that the
reflection is of a black velvet sheet. It works surprisingly well.
Perspective correction in software afterwards squares the image up.
>
> I sometime made prints for that express purpose. This requires
> a whole recalibration of one's mental "Zone System", especially
> what Zones 0, 1, 2, 8, 9 and 10 mean. And so far I have not found
> ink-jet prints that are dark enough in the blacks to equal
> either B&W or color chemical prints.


Agreed. True black is very hard to do. Although this is only obvious
when you have a reference true black nearby to compare with. The eye is
wonderfully good at adapting to the dynamic range it is offered.

Fujicolour Crystal Archive is about as good as I have seen (ignoring for
the moment traditional silver based printing media - which are also not
always a perfect black either).

--
Regards,
Martin Brown
 
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Whisky-dave
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Posts: n/a
 
      08-29-2012
On Wednesday, August 29, 2012 8:06:30 AM UTC+1, Martin Brown wrote:
> On 28/08/2012 22:49, Doug McDonald wrote:
>
> > On 8/28/2012 1:49 PM, Martin Brown wrote:

>
> >

>
> >> It is actually quite hard to distinguish more than about 100 shades of

>
> >> pure grey on print media

>
> >> because of surface scattered and reflected light. Even the very best

>
> >> matt pigments on paper are

>
> >> pathetic blacks when compared to the inside of a ball lined with black

>
> >> velvet.

>
> >

>
> > The best blacks on prints are on the glossiest papers, properly

>
> > lit with a single spot light at an angle. Some papers can get

>
> > well over 1000:1 contrast ratio. Of course, that assumes an

>
> > otherwise black room for background. The results using prints

>
> > so lit with brightness at or approaching sunlight are simply stunning.

>
>
>
> I'd give it more like 500:1 but that is with a black velvet sheet as a
>
> target for the front surface reflection. On ordinary print media even in
>
> glossy magazines you seldom see anything like 100:1.
>
>
>
> I use this trick for photographing old archive material that is too
>
> fragile to flatbed scan in situ side lit at an angle so that the
>
> reflection is of a black velvet sheet. It works surprisingly well.
>
> Perspective correction in software afterwards squares the image up.
>
> >

>
> > I sometime made prints for that express purpose. This requires

>
> > a whole recalibration of one's mental "Zone System", especially

>
> > what Zones 0, 1, 2, 8, 9 and 10 mean. And so far I have not found

>
> > ink-jet prints that are dark enough in the blacks to equal

>
> > either B&W or color chemical prints.

>
>
>
> Agreed. True black is very hard to do. Although this is only obvious
>
> when you have a reference true black nearby to compare with. The eye is
>
> wonderfully good at adapting to the dynamic range it is offered.



http://www.sciencedaily.com/releases...0630082647.htm

Anyone here photgraphed a Black Hole, well there is Hawkins radiation that is emitted but I'm not sure what colour that is

>
>
>
> Fujicolour Crystal Archive is about as good as I have seen (ignoring for
>
> the moment traditional silver based printing media - which are also not
>
> always a perfect black either).
>
>
>
> --
>
> Regards,
>
> Martin Brown


 
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Martin Brown
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      08-29-2012
On 29/08/2012 13:13, bugbear wrote:
> Martin Brown wrote:
>
>>
>> I'd give it more like 500:1 but that is with a black velvet sheet as a
>> target for the front surface reflection. On ordinary print media even
>> in glossy magazines you seldom see anything like 100:1.
>>
>> I use this trick for photographing old archive material that is too
>> fragile to flatbed scan in situ side lit at an angle so that the
>> reflection is of a black velvet sheet. It works surprisingly well.
>> Perspective correction in software afterwards squares the image up.

>
>
> At the risk of topic drift, could you expand on that a little.
>
> I'm struggling to work out where the light, sheet, and camera are.


Usually depending on the subject matter one of either.

Picture hung on a wall camera off axis about 20-30 degrees to left and
space frame with black cloth (ideally velvet) placed so that it blocks
any reflections of background that would be present. Two diffuse lights
above and below the plane to get uniform illumination.

Same sort of thing on a desk with a piece of that 5mm black foam board
providing the dark side and again camera about 30 degrees offset the
other way. ASCII art is pushing it a bit here:

Camera Black card
\ /
\ /
\ /
Subject

Requires an assistant or a retort stand to clamp the black board.

It is mainly of use when there is no way to avoid a square on image
showing a reflection of the camera, room lights or an ornate ceiling.

Same method also works to eliminate glass reflections when photographing
delicate exhibits inside glass cabinets. Control what gets reflected so
that it is close to being uniform and black.

--
Regards,
Martin Brown
 
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Chris Malcolm
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      08-30-2012
In rec.photo.digital Martin Brown <|||newspam|||@nezumi.demon.co.uk> wrote:
> On 28/08/2012 22:49, Doug McDonald wrote:
>> On 8/28/2012 1:49 PM, Martin Brown wrote:


>> The best blacks on prints are on the glossiest papers, properly
>> lit with a single spot light at an angle. Some papers can get
>> well over 1000:1 contrast ratio. Of course, that assumes an
>> otherwise black room for background. The results using prints
>> so lit with brightness at or approaching sunlight are simply stunning.


It's annoying how many galleries are really poorly lit. So when
printing wide range images you either have to print to their
restricted lighting, which prints look silly under good lighting, or
put up with losing lots of dark detail.

> I'd give it more like 500:1 but that is with a black velvet sheet as a
> target for the front surface reflection. On ordinary print media even in
> glossy magazines you seldom see anything like 100:1.


> I use this trick for photographing old archive material that is too
> fragile to flatbed scan in situ side lit at an angle so that the
> reflection is of a black velvet sheet. It works surprisingly well.
> Perspective correction in software afterwards squares the image up.


So the camera is offset too as well as the light. So how do you avoid
(or deal with) the lighting gradient? Do you use two opposed lights
rectangular to the camera view?

--
Chris Malcolm
 
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Chris Malcolm
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      08-30-2012
In rec.photo.digital Martin Brown <|||newspam|||@nezumi.demon.co.uk> wrote:
> On 29/08/2012 13:13, bugbear wrote:
>> Martin Brown wrote:


>>> I'd give it more like 500:1 but that is with a black velvet sheet as a
>>> target for the front surface reflection. On ordinary print media even
>>> in glossy magazines you seldom see anything like 100:1.
>>>
>>> I use this trick for photographing old archive material that is too
>>> fragile to flatbed scan in situ side lit at an angle so that the
>>> reflection is of a black velvet sheet. It works surprisingly well.
>>> Perspective correction in software afterwards squares the image up.

>>
>> At the risk of topic drift, could you expand on that a little.
>>
>> I'm struggling to work out where the light, sheet, and camera are.


> Usually depending on the subject matter one of either.


> Picture hung on a wall camera off axis about 20-30 degrees to left and
> space frame with black cloth (ideally velvet) placed so that it blocks
> any reflections of background that would be present. Two diffuse lights
> above and below the plane to get uniform illumination.


> Same sort of thing on a desk with a piece of that 5mm black foam board
> providing the dark side and again camera about 30 degrees offset the
> other way. ASCII art is pushing it a bit here:


> Camera Black card
> \ /
> \ /
> \ /
> Subject
>
> Requires an assistant or a retort stand to clamp the black board.


> It is mainly of use when there is no way to avoid a square on image
> showing a reflection of the camera, room lights or an ornate ceiling.


> Same method also works to eliminate glass reflections when photographing
> delicate exhibits inside glass cabinets. Control what gets reflected so
> that it is close to being uniform and black.


You've answered my question. I've often thought of doing that, but
never been well organised enough to do more than park a dark clothed
person in the way of the reflections. For small things my
"photographer's scarf" of very black felty wool is a good stand in.

--
Chris Malcolm
 
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