Are IS lenses doomed ?

Rebecca Ore wrote:
In article ,
"Mark²" mjmorgan(lowest even number wrote:

Rebecca Ore wrote:
In article ,
"Neil Harrington" wrote:

Not in their actual focal lengths, no. But 35mm equivalencies are
always given for them, and typically these are zooms of 35-105mm
(equivalent) or thereabouts.

Again, for people who don't know squat about lenses.

Have you always been such a -----?

Especially on Usenet after the first time someone didn't listen to
what I said and asked for someone with a dick to answer his question.

Ah. OK. Well...at least you know you're being a -----. That's a start...

--
Images (Plus Snaps & Grabs) by Mark² at:
www.pbase.com/markuson

In article , Bill Funk
writes
On Fri, 26 Jan 2007 14:12:37 -0500, "Neil Harrington"
wrote:


"Bill Funk" wrote in message
. ..
On Fri, 26 Jan 2007 00:07:25 +0000, Prometheus
wrote:

In article , Bill Funk
writes
On Thu, 25 Jan 2007 07:48:35 -0500, "Neil Harrington"
wrote:

Nothing is cropped. To crop means to remove part(s) of an existing
image.

What do you think is formed at the sensor plane?

The image on the sensor is the full image, not a crop of it, unless you
want to argue that a 35mm frame being less that a 4x5in frame it is also
a crop.

And, once again, someone who wants to bring LF into a 35mm thread.
Get over it.

It's not a 35mm thread, and this isn't a 35mm newsgroup. LF is no more off
topic than 35mm is.

Neil

Correct me if I'm wrong:
This is a discussion of how to describe the difference in the coverage
of the field of view between 35mm frame size and APS-C frame size.
No?

The thread was about IS lenses.

If so, how does anything other than those two frame sizes enter into
the discussion?

It has progressed to discussing the effect on lenses of different images
sizes.*

* There is, of course, none. The image occurs after the light has past
through the lens and can have no effect on the lens.

--
Ian G8ILZ
There are always two people in every pictu the photographer and the viewer.
~Ansel Adams

"David Littlewood" wrote in message
...
In article , Neil Harrington
writes

"David Littlewood" wrote in message
...

No, I can't find any reference to changes in the quart in the last
couple
of centuries. I think you must be misinformed.

You're saying that the English quart was always 40 ounces? That's a
surprise, if true. Our system of measures obviously is based on English
systems of the 18th century, and our quart has always been 32 ounces. The
Imperial units did not arrive until after the Revolutionary War, of
course.
I'll bet you 512 zorknids that before that, the English quart was 32
ounces
also.That "last couple of centuries" may be not quite far enough back.

Possibly; the US gallon is based on the old English wine gallon, whose
origin goes way back but was only formally defined in 1707. It was smaller
than the imperial gallon, and disappeared from use a century or so later
when the imp. gallon became the legal measure. I can't easily find
information of how the wine gallon was made up, and you may be right.

But I think my mistake about the gallon started decades ago when I noticed
that the Imperial gallon was about five U.S. quarts. I just assumed,
wrongly, that the English quart was the same.


Gasoline is a particularly daft name, especially when abbreviated to
"gas", which means that (real) gas has to be called something else.

Yes, but the context usually makes it clear. Probably even wackier is the
old expression "step on the gas" (meaning the accelerator). Stepping on a
gas must be an extraordinarily difficult thing to do.

Oh, Neil, I'm surprised to find you defending an expression which is
"wrong" and which needs to be made clear by the context. g

I know. I did wince a little when I wrote that. :-)




and kerosene paraffin,

Here the UK name is daft, since to a chemist all saturated aliphatic
(open
chain) hydrocarbons are "paraffins". However, kerosene is the term used
by
those "in the business".

Here paraffin is the hard wax used to seal vegetables etc. in Mason jars
when canning. I've never heard of it being used for anything else. So I
was
amazed when the owner's manual for my little Austin Healey advised
cleaning
some parts by washing them in paraffin.

Here "paraffin" means kerosene sold for space heating in the home, "liquid
paraffin" for a particularly revolting oil of some sort sold as a
laxative, and "paraffin wax" the solid stuff used to make candles.

I think it's used to make candles here too, come to think of it.




and all that while (whilst) driving on the wrong side of the road.

We (and the Japanese, among others) probably help cancel out some of the
cyclones caused by your vehicles.

You and the Japanese and Hong Kong and almost no one else. Some of the
other
ex-British colonies, I suppose.

Oh, Neil, Neil, you are most sadly misinformed. This site:

http://users.pandora.be/worldstandar...0left.htm#left
driving

gives a list of 74 countries and territories where one drives on the left,
including India, the second most populous country in the world (about 3.5x
the population of the USA).

I really am surprised! But of course India would qualify as an "ex-British
colony." As for the other 73, I suppose (without having looked at the list)
those would be Australia, New Zealand, Ireland, Scotland, parts of Africa,
Bermuda, and probably every dot in the Atlantic, Pacific or Indian Oceans
that flies or ever did fly the British flag, eh? Other than Japan, any
non-British-background wrong-side drivers?

I just did look at that article. Very interesting. Some places I've never
(or only vaguely) heard of.

Neil

"Neil Harrington" wrote:

Here paraffin is the hard wax used to seal vegetables etc. in
Mason jars when canning. I've never heard of it being used for
anything else. So I was amazed when the owner's manual for my
little Austin Healey advised cleaning some parts by washing them
in paraffin.

Some people use melted paraffin wax to clean and lubricate bicycle
chains, but I doubt that's what Austin Healey had in mind.

--
Ray
(remove the Xs to reply)

nick c wrote:

In the meantime, nations in this world still accept the
standard passing of time as 60 seconds equals one minute and 60
minutes equal one hour though I suspect horologists are working
to find a way to metrically change the way time is measured. Thus
rendering all the standard time pieces presently used throughout
the world, obsolete. :-)

It was tried during the French Revolution - a day was 10 hours of 100
minutes of 100 seconds. I've seen pictures of clocks with 10-hour
dials http://en.wikipedia.org/wiki/Decimal_time. They also changed
the calendar to have 10-day weeks. Neither innovation caught on.
Imagine having to work eight days between weekends.

I'm reminded of an old Saturday Night Live sketch about the decimal
alphabet.

--
Ray
(remove the Xs to reply)

John Francis wrote:
[...]
A quick question: without calculation, which do you think would be heavier?
A substance with a density of 20 grams per litre, or one with a density
of 20 ounces per cubic foot?

The densities are too close to do without calculation.
Fortunately it's now just a matter of typing

20 grams per litre in ounces per cubic foot

into Google.


--
--Bryan

In article ,
Alan Browne wrote:

Rebecca Ore wrote:

And firmly illustrates that 35mm photographers are generally not very
knowledgeable about lenses and never should crosspost into the medium
and large format groups.

I guess you completely misunderstand why there are newsgroups in the
first place.

Okay, most 35 mm camera users should learn from people who think about
lenses in different ways that actually come from lens physics than
marketing terminology.

I have a D-50 with a 50mm short telephoto lens and a Leica with a 50 mm
normal lens -- there's no need to convert anything since I can see what
I'm getting through the viewfinder on the D50 and the Leica's viewfinder
gives 100% coverage at 10 feet. Multiplying the Leica's 50 mm lens by
the Nikon's focal length multiplier would be useless because the
Summitar won't fit on the D50.

In article ,
Alan Browne wrote:

Rebecca Ore wrote:

To me, the people who use "crop factor" tend to be people who came out
of 35 mm consumer photography, not people with experience with a range
of different possibilities and some reading on lens design.

No. It's everyone whether "amateur" or "pro" who has a bag of lenses
and has to adapt to it. No big deal for most ranges, but wide angle
gets to be a challenge, one way or another. My general purpose walk
around lens, 28-70 f/2.8 is now pretty limited as a wide angle lens when
used on a cropped sensor. My 80-200 f/2.8 is now a fabulous lens for
walks in the woods. My 20mm has become a bit of an orphan.

Most but not all amateurs have 35 mm cameras. Many but not all
professionals have 35 mm cameras. There is medium format digital, and
the price is coming down.


The PITA is all the "digital" lenses with reduced image circles and the
ongoing liklihood that Nikon (and possibly Sony) put out FF sensors.

They're cheaper to make than lenses with a larger image circle.

In article ,
"Mark²" mjmorgan(lowest even number wrote:

Rebecca Ore wrote:
In article ,
"Mark²" mjmorgan(lowest even number wrote:

Rebecca Ore wrote:
In article ,
"Neil Harrington" wrote:

Not in their actual focal lengths, no. But 35mm equivalencies are
always given for them, and typically these are zooms of 35-105mm
(equivalent) or thereabouts.

Again, for people who don't know squat about lenses.

Have you always been such a -----?

Especially on Usenet after the first time someone didn't listen to
what I said and asked for someone with a dick to answer his question.

Ah. OK. Well...at least you know you're being a -----. That's a start...

Women know they've won the argument when they get called bitch or are
accused of arguing like a man.

David Littlewood wrote:
In article , nick c
writes

Units of measurement are theoretical. A standard unit of measurement
is whatever is accepted by international standardization agreement.

Indeed.

It would be interesting to learn what units of measurement are used by
alien space travelers, if indeed there are such things as alien space
travelers. In the meantime, nations in this world still accept the
standard passing of time as 60 seconds equals one minute and 60
minutes equal one hour though I suspect horologists are working to
find a way to metrically change the way time is measured. Thus
rendering all the standard time pieces presently used throughout the
world, obsolete. :-)

The definition of the second (the SI unit of time) has changed over the
years - at least two definitions in astronomical terms in the 1950s. In
1964 the definition was changed to be the duration of 9,192,631,770
periods of the radiation corresponding to the transition between two
hyperfine levels (F=4, M=0 and F=3, M=0) of the ground state of the
caesium 133 atom.

David


That should read, the ground state of the caesium 133 atom ..... at 0
Kelvin. Thereby using agreed upon theory to define time interval but not
the common state of time of day. My posted concern was related to
defining what a metric day would be as made up from the passing of the
time it takes for the earth to make one revolution, which is not 24
hours but 25 hours. Using 25 hours, each hour would then (using metric
units divisible by 10) be divided into 100 metric minutes and each
metric minute would then be 100 metric seconds. Thus a day would not
consist of 86,400 seconds but 250,000 metric seconds. When pressed to go
metric, commonly used time pieces used throughout the world would become
obsolete. The common mechanical clock/wris****ch keeps time using the
traditionally accepted 60 sec x 60 min x 24 hr/day = 86,400 sec/day.
Using metric time would be 100 metric sec. x 100 metric min. x 25
hr/day = 250,000 metric seconds/day. The hour would change from one hour
being composed of 60 minutes to one metric hour being composed of 57.6
minutes. The common clock/watch would be short 2.4 minutes/day.
Discounting your explanation of a SI unit of time, I think I would be
correct in saying all the standard time pieces presently used throughout
the world would become obsolete. Past accepted time recording practices
then becoming obsolete would have a domino effect upon written history
of mankind.

If, or when (whichever the case) a change of common time is proposed and
might well be accepted by the ISO, would you still find engineering data
incomprehensible if time related data was not, or did not, make
reference to metric time changes? Would you expect world (or the US,
for that matter) use of common standard time to be trashed in favor of
using metric time, just because the ISO accepted the definition of what
common standard time should be? Wouldn't history have to be rewritten
just to satisfy metrication. Years from now would you really care one
way or another? :-)