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I have placed a file here:
http://photoviki.com/displayimage.ph...at=10196&pos=0

or if that doesn't work here:
http://photoviki.com/albums/userpics/10196/ece.jpg

Even with much help from this group I was unable to do a professional
job of using arrows to point at the problems. The best I could do was
to type text directly underneath the problem. I have ordered CS2 so
when it gets here I will figure out the arrow thing. BTW, these
problems occur any time I am working with silhouettes. I have only had
the lens off the camera once and that was to replace the kit lens with
a prime a few days ago. The distortion I point out in the picture was
there before I changed the lens, except for the four point star. I
always keep the camera in a plastic bag because the dust in this part
of Oklahoma is relentless. The blue dot varies in size, as well as
some other blue and red dots that I did not point out. The brown dot
is always more or less in focus.
Can someone tell me what these distortions are?

Thanks again,
Ron

My first guess would be that's it's a flare.

A flare is light reflecting around inside of the lens caused by a
bright light shining towards the lens. Set up the silhouette again and
get it to do it. If it's a flare, it will move around on you as you
move your camera. That's your first test. Then, take a piece of
cardboard and place it in between the microscope and the camera,
directly in line with the light source so no direct light shines on the
camera. If it's a flare, then it'll go away.

Then shine a light on a plain wall so it is very diffused and soft.
Photograph it. It should be okay with indirect light.

Then, put your lens cap on and take a exposure of 10 seconds or so. It
should be black (or reasonably close to it).

If the flare stays in exactly the same place, if the diffused light on
the wall causes it, if the cardboard doesn't stop it, or if the
lens-cap test shows it, post the results.

Good luck.

<> wrote:
>I have placed a file here:
>http://photoviki.com/displayimage.ph...at=10196&pos=0
>
>or if that doesn't work here:
>http://photoviki.com/albums/userpics/10196/ece.jpg
>
>Even with much help from this group I was unable to do a professional
>job of using arrows to point at the problems. The best I could do was
>to type text directly underneath the problem. I have ordered CS2 so
>when it gets here I will figure out the arrow thing. BTW, these
>problems occur any time I am working with silhouettes. I have only had
>the lens off the camera once and that was to replace the kit lens with
>a prime a few days ago. The distortion I point out in the picture was
>there before I changed the lens, except for the four point star. I
>always keep the camera in a plastic bag because the dust in this part
>of Oklahoma is relentless. The blue dot varies in size, as well as
>some other blue and red dots that I did not point out. The brown dot
>is always more or less in focus.
>Can someone tell me what these distortions are?

The star is lens flare. Either remove the UV filter from the lens or
rent a better lens. The dots are bad pixels in the sensor and are
quite common in digital cameras. They tend to show up more in long
exposures.

The dots are trivially fixed using Photoshop. The flare can be fixed
in Photoshop as well but it would be a lot harder and eliminating the
problem in the lens would be best.

--
Ray Fischer