"Dick" <Tungfree@hawaii.rr.com> wrote in message
news:CMwLa.57026$98.1924803@twister.socal.rr.com...
>
> I had to refresh my memory of  "focal length" and looked it up:
>
> FOCAL LENGTH
>
> This is the distance (in mm.), in an optical system, from the lens (or
> primary mirror) to the point where the telescope is in focus (focal
point).
> The longer the focal length of the telescope, generally the more power it
> has, the larger the image and the smaller the field of view. For example,
a
> telescope with a focal length of 2000mm has twice the power and half the
> field of view of a 1000mm telescope. Most manufacturers specify the focal
> length of their various instruments; but, if it is unknown and you know
the
> focal ratio you can use the following formula to calculate it: focal
length
> is the aperture (in mm) times the focal ratio. For example, the focal
length
> of an 8" (203.2mm) aperture with a focal ratio of f/10 would be 203.2 x 10
=
> 2032mm.
>
> JK How do we apply the above to te C5050 and the C4000  for example? could
> you site one you would look at to make a decision with?
>
> Dick
>
> "JK" <JK9821@netcape.net> wrote in message
> news:3EFE140C.A2904FE1@netcape.net...
> >
> >
> > Tesselator wrote:
> >
> > > "Dick" <Tungfree@hawaii.rr.com> wrote in message
> news:ADiLa.127379$x67.5751859@twister.socal.rr.com...
> > > > The Olympus C-4000 4MP has a wonderful Macro feature going to about
> one inch
> > > > to take a shot of a bee. The C4040 4.1 MP, suposedly a super set of
> the
> > > > C-4000 does not have that super Macro and begins near 8". The new
> C5050
> > > > 5MPhowever is outfited with that macro of near 1".
> > > > So either I seek the C4000 4MP or the C5050 at 5MP.
> > > > What other cameras have such a Macro near 1" ?
> > >
> > > Many (all?) models in the CoolPix line have 4cm or less in macro mode.
> > >
> > > > This News group seems very focused near the 3MP. I have read all
your
> posts
> > > > comparing te A40/A60/A70 With te Nikon 2100/3100 looked at the
> pictures, but
> > > > have no such input for the C4000 Olympus nor any for the C5050 to
see
> if I
> > > > would ever need such resolutions of 4MP/5MP and the expense of them.
> > >
> > > It's probably just a result of the depth of the average consumers
> > > pocket-book.  Both the 4040 and the 5050 are excellent cameras I will
> > > buy a 5050 soon I think to add to my collection.  Don't be put off by
> > > the working range of a camera's macro mode which in the 4040 is 0.2 -
> 0.8 m
> > > but rather focus your attention of the level of magnification it is
> > > capable of.  I would much rather have a working range of a foot or
more
> > > if I could still get the same magnification as a macro engeneered to
> > > operate at minute distances.
> >
> > Since the cameras being discussed have lenses of almost
> > the same focal lengths and sensors of similar sizes,
> >  the degree of "magnification" will vary depending on the
> > distance. With film cameras, magnification is the ratio of the
> > size on film to the size of the object. Since with digital there is
> > no film, one should define magnification in terms of pixels per
> > centimeter or pixels per inch of the subject. This will depend
> > on the distance to the subject, the relative focal length the lens
> > is set at (relative to the sensor size. For convenience,
> > digital cameras show an equivalent focal length compared
> > to 35mm cameras), and the resolution that the camera is set at.
> >
> >
> >
> > >
> > >
> > > As far as the expense and usefulness of a 5MP unit I guess you alone
> > > can answer that.  What will you be using the camera for? etc.
> > >
> > > >
> > > > I welcome suggestions beands and models to look at and consider. And
> the
> > > > advice of where to limit the quality persuits (weakness) I or many
of
> you
> > > > may have :).
> > > > What to do what to do....hmmmmm
> > > >
> > > > Dick in Hawaii
> > >
> > > Someone should make a FAQ if there isn't one already, of the "ideal"
> > > features to look for in a digital camera.  Like:
> > >
> > > The ability to go manual in as many aspects as possible.
> > > The ability to store and transfer uncompressed images.
> >
> > Not that many people shoot uncompressed on consumer level cameras.
> > The quality difference is hardly noticeable compared with shooting
> > at low  compression(SHG?), yet shooting uncompressed yeilds
> > files that are much larger, and the much lower number of images
> > per flash card can be very annoying.
> >
> >
> > >
> > > The ability to add attachements (PC, Hotshoe, Tripod mount, lens
> filters, etc.)
> >
> > >
> > > Readable LCD menus
> > > Tilt/Rotate/Swivel LCD Pannels.
> > > All glass (coated) lens elements.
> > > Other than plastic body frame,
> > > USB or Serial Camera Control via computer or etc. (other than
> downloading)
> > > Etc.
> > > Etc.
> > > Etc.
> > >
> > > And thier _simple_ respective explaination.  Like:
> > >
> > > USB/Ser. Cam. Control  --  Will allow you to to create ultra hi res
stop
> motion
> > >                            and time-laps motion sequences.
> >
> > Very few people do this.
> >
> > >
> > >
> > > Non-Plastic Cam Body   --  Will save you a trip to the repair shop if
> you drop
> > >                            the thing.
> > >
> > > Etc.
> > > Etc.
> > > Etc.
> > >
> > > Anyone know of a faq like that?
> >
>
>