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what are the light spots on the background of the above photo?

updated fri 26 may 06

 

Russel Fouts on tue 19 jul 05


Question for Clayart:
What are the light spots on the background of the above photo?
- The camera is a Canon C-4000 Z Digital
- They appear in the same place on all the digital images and prints.
- They are more apparent when there is more light
- The lens is clean as far as I can see
- Could it be a side effect of having the shutter stopped down as far
as it can go? (which is only F11) There is a name for that but I forget.

You can see the photo on my Clayart Show Window Page at:

http://users.skynet.be/russel.fouts/clayart.htm

I'd like to not have them. Any ideas?

Thanks in advance.

Russel



Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 3000 Pottery Related Links!
Updated frequently

My work can also be seen on:
The World Crafts Council Belgium Site http://wcc-bf.org:
Members English Pages: http://wcc-bf.org/artistes/ukrussel_fouts.htm
EasyCraft: http://www.easycraft.org

"To announce that there must be no criticism of the president, or that
we are to stand by the president, right or wrong, is not only
unpatriotic and servile, but is morally treasonable to the American
public." --U.S. President (and Nobel Peace Prize winner) Theodore
Roosevelt.

Tony Ferguson on tue 19 jul 05


Russel,

It is dust on your image sensor. You should probably have it professionally cleaned or learn how the pros do it. If you scratch it, it's there forever. Welcome to digital my friend.

Tony


Russel Fouts wrote:
Question for Clayart:
What are the light spots on the background of the above photo?
- The camera is a Canon C-4000 Z Digital
- They appear in the same place on all the digital images and prints.
- They are more apparent when there is more light
- The lens is clean as far as I can see
- Could it be a side effect of having the shutter stopped down as far
as it can go? (which is only F11) There is a name for that but I forget.

You can see the photo on my Clayart Show Window Page at:

http://users.skynet.be/russel.fouts/clayart.htm

I'd like to not have them. Any ideas?

Thanks in advance.

Russel



Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 3000 Pottery Related Links!
Updated frequently

My work can also be seen on:
The World Crafts Council Belgium Site http://wcc-bf.org:
Members English Pages: http://wcc-bf.org/artistes/ukrussel_fouts.htm
EasyCraft: http://www.easycraft.org

"To announce that there must be no criticism of the president, or that
we are to stand by the president, right or wrong, is not only
unpatriotic and servile, but is morally treasonable to the American
public." --U.S. President (and Nobel Peace Prize winner) Theodore
Roosevelt.

______________________________________________________________________________
Send postings to clayart@lsv.ceramics.org

You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/

Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.


Tony Ferguson
...where the sky meets the lake...
Duluth, Minnesota
Artist, Educator, Web Meister
fergyart@yahoo.com
fergy@cpinternet.com
(218) 727-6339
http://www.aquariusartgallery.com
http://www.tonyferguson.net
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John Anthony on tue 19 jul 05


Hi Russell-
Wow,I thought I was the only person this happened to. I have a Canon
EOS 300
(Digital Rebel). It only happens when the lens is stopped all the way
down. I thought it
was damage to the background, spots on the lens...no, it's a technical
issue. I haven't tried
contacting Canon about it,but now Iwill.
John A
http://www.redhillpottery.com

John Anthony on wed 20 jul 05


Here's a link to a site with cmos sensor cleaning tips.

http://www.pictureline.com/newsletter/2004/june/dslrclean.html



John A
http://www.redhillpottery.com

Brian O'Neill on wed 20 jul 05


Russel,

Not sure I'm seeing what you're talking about, but here's two thoughts.
"Depth of Field" is what you refer to regarding the f-stop and I don't
think that's the problem. It looks to me like the image degraded when
you scaled down and/or changed resolutions. Is the image 72ppi? You may
want to scale down to the intended size before you reduce the
resolution to 72ppi. (I'm assuming the original digital image was a
higher resolution.) If not, and you enlarged the image, you get
anomalies in the pixels as it has to add more pixels to "create" the
larger image. This is called interpolation, and the image will suffer
if there isn't enough pixel information to begin with. I think this is
what's going on. Look at the edge of your piece--there's a fuzzy
quality to the pixels there that hints at funky interpolation. The
Funky Interpolation is also the latest dance craze sweeping the geek
night life scene.

That the spots appear in the same place on all images is the curious
thing. The only thing I can think of (and I can't see this on your
images, which is why I'm not sure I'm seeing what you're talking about)
is cell or pixel burnout from your camera. In Photoshop or any image
editing program, if you zoom in to look at individual pixels and see a
totally white one (in a dark area), then this may be the problem. A
more expensive fix to be sure.

Hope this helps,
Brian
Brian O'Neill
Principal | O'Neill Design
2985 Goshen Rd | Bellingham, WA | 98226 | 360 592 3164
brianoneill@cablespeed.com

On Jul 19, 2005, at 1:43 PM, Russel Fouts wrote:

> Question for Clayart:
> What are the light spots on the background of the above photo?
> - The camera is a Canon C-4000 Z Digital
> - They appear in the same place on all the digital images and prints.
> - They are more apparent when there is more light
> - The lens is clean as far as I can see
> - Could it be a side effect of having the shutter stopped down as far
> as it can go? (which is only F11) There is a name for that but I
> forget.
>
> You can see the photo on my Clayart Show Window Page at:
>
> http://users.skynet.be/russel.fouts/clayart.htm
>
> I'd like to not have them. Any ideas?
>
> Thanks in advance.
>
> Russel
>
>
>
> Russel Fouts
> Mes Potes & Mes Pots
> Brussels, Belgium
> Tel: +32 2 223 02 75
> Mobile: +32 476 55 38 75
>
> Http://www.mypots.com
> Home of "The Potters Portal"
> Over 3000 Pottery Related Links!
> Updated frequently
>
> My work can also be seen on:
> The World Crafts Council Belgium Site http://wcc-bf.org:
> Members English Pages: http://wcc-bf.org/artistes/ukrussel_fouts.htm
> EasyCraft: http://www.easycraft.org
>
> "To announce that there must be no criticism of the president, or that
> we are to stand by the president, right or wrong, is not only
> unpatriotic and servile, but is morally treasonable to the American
> public." --U.S. President (and Nobel Peace Prize winner) Theodore
> Roosevelt.
>
> _______________________________________________________________________
> _______
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>

Tony Ferguson on wed 20 jul 05


Hey John,

I first notice spots when I was doing tests with F22 and higher as well. It's a pain trying to clean, but I think I will pick up some of the cleaning supplies you recommended. Thanks.

Tony Ferguson


John Anthony wrote:
Hi Russell-
Wow,I thought I was the only person this happened to. I have a Canon
EOS 300
(Digital Rebel). It only happens when the lens is stopped all the way
down. I thought it
was damage to the background, spots on the lens...no, it's a technical
issue. I haven't tried
contacting Canon about it,but now Iwill.
John A
http://www.redhillpottery.com

______________________________________________________________________________
Send postings to clayart@lsv.ceramics.org

You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/

Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.


Tony Ferguson
...where the sky meets the lake...
Duluth, Minnesota
Artist, Educator, Web Meister
fergyart@yahoo.com
fergy@cpinternet.com
(218) 727-6339
http://www.aquariusartgallery.com
http://www.tonyferguson.net

---------------------------------
Yahoo! Mail
Stay connected, organized, and protected. Take the tour

Earl Brunner on wed 20 jul 05


Unlikely, and with the SLR only if you remove the lens (frequently or in a
dusty environment)

Earl Brunner
Las Vegas, NV
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Russel Fouts
Sent: Wednesday, July 20, 2005 4:51 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: What are the light spots on the background of the above photo?

Thanks, Can the dust still get there if the camera isn't an SLR? It
would probably cost more than the camera is worth ($450 - 2 years) to
get it professionally cleaned.

Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 1800 Pottery Links!
Updated frequently

Tony Ferguson on thu 21 jul 05


Russel,

Even if your dig camera is a viewfinder type, if your lend extends outward, it is sucking in air. I would suggest you bring it to an authorized canon dealer for cleaning or learn how to use the clone tool in Photoshop or the Gimp (open source & free).

Tony Ferguson

Russel Fouts wrote:
Brian and John,

John, thanks for the link but my camera isn't an SLR, I don't think I
could get into it easily to clean it.

Brian, The images begin life as high resolution tifs, the spots show
up on the original images (even on the camera if I zoom in on the
image). The spots are definitely larger than 1 pixtel. And the reason
the edges look a little fuzzy is because I have to rely on autofocus
because the manual focus on this camera is difficult to use. Which is
one reason I want to replace it next year with a digital SLR.

I'm still betting that it's either dirt (which I'm not sure I can do
too much about) or the "fault who's name I can't remember that you
can get when you stop the aperture down all the way". I worked in my
studio, where the book I want is, all day but forgot to take a look at it.

I got too involved in arranging chemical storage and washing buckets.
I now have all my chemicals out of those nasty bags and into nice
sealable buckets. AND I actually have more buckets than I can easily
store. Both are a very good thing!

Tomorrow I'm buying some compressed air at the photo shop, shopping
for my holiday which starts in a week, Looking for "the fault whose
name I can't remember", cleaning my camera and shooting some pots for
the 2007 NCECA Clayart Show to have them in before the deadline. I'll
try not stopping the aperture down all the way this time to see if
that makes a difference.

I guess you could call that Funky Interpolation.

Thanks again,

Russel



Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 3000 Pottery Related Links!
Updated frequently

My work can also be seen on:
The World Crafts Council Belgium Site http://wcc-bf.org:
Members English Pages: http://wcc-bf.org/artistes/ukrussel_fouts.htm
EasyCraft: http://www.easycraft.org

"To announce that there must be no criticism of the president, or that
we are to stand by the president, right or wrong, is not only
unpatriotic and servile, but is morally treasonable to the American
public." --U.S. President (and Nobel Peace Prize winner) Theodore
Roosevelt.

______________________________________________________________________________
Send postings to clayart@lsv.ceramics.org

You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/

Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.


Tony Ferguson
...where the sky meets the lake...
Duluth, Minnesota
Artist, Educator, Web Meister
fergyart@yahoo.com
fergy@cpinternet.com
(218) 727-6339
http://www.aquariusartgallery.com
http://www.tonyferguson.net

---------------------------------
Start your day with Yahoo! - make it your home page

Carl Finch on thu 21 jul 05


At 05:39 PM 7/21/2005, Russel Fouts wrote:

>Tomorrow I'm buying some compressed air at the photo shop, shopping
>for my holiday which starts in a week, Looking for "the fault whose
>name I can't remember", cleaning my camera and shooting some pots for
>the 2007 NCECA Clayart Show to have them in before the deadline. I'll
>try not stopping the aperture down all the way this time to see if
>that makes a difference.

One of the folks that offered you a suggestion (I ferget who) included a
URL to a how-to-clean-it site. And that site cautioned *against* using
something as powerful as compressed air (granted, it was in reference to a
DSLR).

I've been following a Kodak e-list for 6 years (and more recently one for
Minolta) and have not seen complaints of the problem you've
experienced. There *have* been several complaints of dust in the optical
view finder, but of course that doesn't affect photos (the view finder of
my Kodak DC290 has a few). Your spots look very much like the flash photos
I've made of campfires and falling snow--the result of the flash's lighting
up nearby and out-of-focus smoke particles and snow flakes.

You might try joining a Canon e-list (there are likely several of them in
Yahoo groups) and asking how folks with your camera (or similar ones) have
fixed this problem. Heck, dusk leakage could be a known problem with that
model!

--Carl
in Medford, Oregon

Russel Fouts on thu 21 jul 05


Tony,

>> It is dust on your image sensor. You should probably have it professionally cleaned or learn how the pros do it. If you scratch it, it's there forever. Welcome to digital my friend. <<

Thanks, Can the dust still get there if the camera isn't an SLR? It
would probably cost more than the camera is worth ($450 - 2 years) to
get it professionally cleaned.

Thanks for the other suggestions everyone, I'm going to get some
compressed air (not really sure where to blow) and will also try
changing the position of the lights to see if the spots move.

I'm already planning to buy a better camera next year, probably a
Digital Rebel or Rebel XT.

Russel (did I remember to say thanks?)

--
Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 1800 Pottery Links!
Updated frequently

"To announce that there must be no criticism of the president,
or that we are to stand by the president, right or wrong,
is not only unpatriotic and servile, but is morally treasonable
to the American public."

U.S. President (and Nobel Peace Prize winner) Theodore Roosevelt.

Russel Fouts on thu 21 jul 05


John

>> Wow,I thought I was the only person this happened to. I have a Canon EOS 300
(Digital Rebel). It only happens when the lens is stopped all the way
down. I thought it was damage to the background, spots on the lens...no,
it's a technical issue. I haven't tried contacting Canon about it,but
now I will.<<

I think it's a known problem with all cameras, something that happens to
the light when it comes through such a small hole. There is a name for
it that escapse me (escapes Suzanne Tourtillott so I'm not the only one
with a faulty memory). I'll look it up tomorrow when I get home (I'm at
Enzo's tonight).

Anyway, the upshot is that Canon will tell you the name of the problem
when you call them. ;-)

Russel

--
Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 1800 Pottery Links!
Updated frequently

"To announce that there must be no criticism of the president,
or that we are to stand by the president, right or wrong,
is not only unpatriotic and servile, but is morally treasonable
to the American public."

U.S. President (and Nobel Peace Prize winner) Theodore Roosevelt.

Russel Fouts on fri 22 jul 05


Brian and John,

John, thanks for the link but my camera isn't an SLR, I don't think I
could get into it easily to clean it.

Brian, The images begin life as high resolution tifs, the spots show
up on the original images (even on the camera if I zoom in on the
image). The spots are definitely larger than 1 pixtel. And the reason
the edges look a little fuzzy is because I have to rely on autofocus
because the manual focus on this camera is difficult to use. Which is
one reason I want to replace it next year with a digital SLR.

I'm still betting that it's either dirt (which I'm not sure I can do
too much about) or the "fault who's name I can't remember that you
can get when you stop the aperture down all the way". I worked in my
studio, where the book I want is, all day but forgot to take a look at it.

I got too involved in arranging chemical storage and washing buckets.
I now have all my chemicals out of those nasty bags and into nice
sealable buckets. AND I actually have more buckets than I can easily
store. Both are a very good thing!

Tomorrow I'm buying some compressed air at the photo shop, shopping
for my holiday which starts in a week, Looking for "the fault whose
name I can't remember", cleaning my camera and shooting some pots for
the 2007 NCECA Clayart Show to have them in before the deadline. I'll
try not stopping the aperture down all the way this time to see if
that makes a difference.

I guess you could call that Funky Interpolation.

Thanks again,

Russel



Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 3000 Pottery Related Links!
Updated frequently

My work can also be seen on:
The World Crafts Council Belgium Site http://wcc-bf.org:
Members English Pages: http://wcc-bf.org/artistes/ukrussel_fouts.htm
EasyCraft: http://www.easycraft.org

"To announce that there must be no criticism of the president, or that
we are to stand by the president, right or wrong, is not only
unpatriotic and servile, but is morally treasonable to the American
public." --U.S. President (and Nobel Peace Prize winner) Theodore
Roosevelt.

Russel Fouts on thu 25 may 06


Tony, John, Suzanne, Everyone who responded,

I found this unsent thank you in my outbox, sorry about the delay.

Thanks for all your help. It turned out to be just some stubborn
spots on the lense. I got a really good cleaning kit and some
compressed air and gave it a good cleaning. The spots have
disappeared! I also sent a little blast of compressed air in where
the zoom barrels telescope over each other, don't know if that did anything.

Anyway my pictures look much better now.

I also discovered the Automatic White Balance feature on my camera.
Set this up, hold a white card in front of the camera and click the
button. The camera adjusts itself and your color balance is almost
perfect. DUH!

Now, if I could just figure out how to get rid of the haze that
adjusting the levels in Photoshop gets rid of I'd be all set. I could
send perfect, unaltered images!

Thanks again to the great, common brain.

Russel (I'm just another neuron in the chain) Fouts

At 05:46 21/07/2005, you wrote:
>Russel,
>
>Dust can get in there, but if its a closed lens system, it is less
>likely. When a lens expands or contracts, it draws air from the
>seams sucking in, you guessed it, dust.
>
>Tony Ferguson
>
>
>
>Russel Fouts wrote:
>Tony,
> >> It is dust on your image sensor. You should probably have it
> professionally cleaned or learn how the pros do it. If you scratch
> it, it's there forever. Welcome to digital my friend. <<
>Thanks, Can the dust still get there if the camera isn't an SLR? It
>would probably cost more than the camera is worth ($450 - 2 years) to
>get it professionally cleaned.
>Thanks for the other suggestions everyone, I'm going to get some
>compressed air (not really sure where to blow) and will also try
>changing the position of the lights to see if the spots move.
>I'm already planning to buy a better camera next year, probably a
>Digital Rebel or Rebel XT.
>Russel (did I remember to say thanks?)
>--
>Russel Fouts
>Mes Potes & Mes Pots
>Brussels, Belgium
>Tel: +32 2 223 02 75
>Mobile: +32 476 55 38 75
>
>Http://www.mypots.com
>Home of "The Potters Portal"
>Over 1800 Pottery Links!
>Updated frequently
>"To announce that there must be no criticism of the president,
>or that we are to stand by the president, right or wrong,
>is not only unpatriotic and servile, but is morally treasonable
>to the American public."
>U.S. President (and Nobel Peace Prize winner) Theodore Roosevelt.
>
>
>
>Tony Ferguson
>...where the sky meets the lake...
>Duluth, Minnesota
>Artist, Educator, Web Meister
>fergyart@yahoo.com
>fergy@cpinternet.com
>(218) 727-6339
>http://www.aquariusartgallery.com
>http://www.tonyferguson.net
>
>__________________________________________________
>Do You Yahoo!?
>Tired of spam? Yahoo! Mail has the best spam protection around
>http://mail.yahoo.com


Russel Fouts
Mes Potes & Mes Pots
Brussels, Belgium
Tel: +32 2 223 02 75
Mobile: +32 476 55 38 75

Http://www.mypots.com
Home of "The Potters Portal"
Over 3000 Pottery Related Links!
Updated frequently

My work can also be seen on:
The World Crafts Council Belgium Site http://wcc-bf.org:
Members English Pages: http://wcc-bf.org/artistes/ukrussel_fouts.htm
EasyCraft: http://www.easycraft.org

"To announce that there must be no criticism of the president, or that
we are to stand by the president, right or wrong, is not only
unpatriotic and servile, but is morally treasonable to the American
public." --U.S. President (and Nobel Peace Prize winner) Theodore
Roosevelt.