dark 'outline' around image?

Archived from groups: rec.photo.digital (More info?)

Any way to offer an example, so that we are not blindly speculating,
and including the possiblity of demonic possession? <grin>

Archived from groups: rec.photo.digital (More info?)

frankg wrote:
> I have a great shot of my nephew fishing on a dock/pier that I took with my
> brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
> around the subject. The pic was taken at sunset, ambient light (low light
> levels) without fill flash and is backlit (semi-silhouette). The image was
> shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> process. The 'outline' gets worse when I bring it into Photoshop and try to
> sharpen it. What is this and how can it be avoided ?
>
> I've noticed it on other digital images I shot too.
> thanks
>
I think it's those aliens trying to communicate with us again! If you
don't wear your aluminum foil helmet, they get control of your brain
and mess up your pictures. It may be too late for your nephew...

Archived from groups: rec.photo.digital (More info?)

Jim Townsend wrote:
> frankg wrote:
>
> > I have a great shot of my nephew fishing on a dock/pier that I took with my
> > brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
> > around the subject. The pic was taken at sunset, ambient light (low light
> > levels) without fill flash and is backlit (semi-silhouette). The image was
> > shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> > process. The 'outline' gets worse when I bring it into Photoshop and try to
> > sharpen it. What is this and how can it be avoided ?
>
> The background is extremely blown out...
>
> The fringe appears to be a flare caused by the grossly
> overexposed background bleeding over..

Can you, Jim, or someone else, elaborate on this comment? I'm just
getting into digital photography (did a lot of film photograpy years
ago) and I'm curious. A few questions come to mind. How would you
properly expose a pic like this? If you stop down enough to get the
water better, won't you lose the boys face? Is the dynamic range of
this picture just too much (i.e., more than 5 stops?)? Is fill flash a
viable option here? Wouldn't you have to have one helluva flash unit to
do much good in this situation? How would a histogram help in taking
this picture?
Moving to the digital darkroom...
What could you do to fix this pic? Is it saveable in RAW format? In
JPEG?
Seems like there could be an entire digital photo course just working
with this image!

Archived from groups: rec.photo.digital (More info?)

wilt wrote:
> Any way to offer an example, so that we are not blindly speculating,
> and including the possiblity of demonic possession? <grin>

Don't discount that possibility.

It's also a known principle that Other Peoples' Cameras sabotage your
efforts if you haven't made appropriate preliminary obeisances.

--
Frank ess

Archived from groups: rec.photo.digital (More info?)

> Any way to offer an example, so that we are not blindly speculating,
> and including the possiblity of demonic possession? <grin>
>

I have uploaded 3 files here http://www.frankgross.com/temp/
one is the entire frame.
another is cropped around the boy so you can see the 'dark outline'
and a third is the the file up- res 'd in photoshop (bicubic smoother) 200%
so you can better see the dark outline

Archived from groups: rec.photo.digital (More info?)

frankg wrote:

> I have a great shot of my nephew fishing on a dock/pier that I took with my
> brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
> around the subject. The pic was taken at sunset, ambient light (low light
> levels) without fill flash and is backlit (semi-silhouette). The image was
> shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> process. The 'outline' gets worse when I bring it into Photoshop and try to
> sharpen it. What is this and how can it be avoided ?

The background is extremely blown out...

The fringe appears to be a flare caused by the grossly
overexposed background bleeding over..

Archived from groups: rec.photo.digital (More info?)

>
>> I have a great shot of my nephew fishing on a dock/pier that I took with
>> my
>> brother's 6 MP Canon Digital Rebel. The main problem being a dark
>> 'outline'
>> around the subject. The pic was taken at sunset, ambient light (low light
>> levels) without fill flash and is backlit (semi-silhouette). The image
>> was
>> shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
>> process. The 'outline' gets worse when I bring it into Photoshop and try
>> to
>> sharpen it. What is this and how can it be avoided ?
>
> The background is extremely blown out...
>
> The fringe appears to be a flare caused by the grossly
> overexposed background bleeding over..
>
Yes it's overexposed with the sun kicking off the water - but on the
original, when I run the Photoshop Info cursor over the hottest spots
they're still under 255. Would that still cause a dark "fringing"?

Archived from groups: rec.photo.digital (More info?)

salgud wrote:

> Jim Townsend wrote:

>> The background is extremely blown out...
>>
>> The fringe appears to be a flare caused by the grossly
>> overexposed background bleeding over..
>
> Can you, Jim, or someone else, elaborate on this comment? I'm just
> getting into digital photography (did a lot of film photograpy years
> ago) and I'm curious.

Flare is not uncommon where extremely bright areas meet dark areas.

I've read that this is caused by some of the strong charge in the
light area bleeding over to adjacent sensor sites on the camera's
sensor. The fact that lens glass is never optically perfect might
exacerbate the problem.

Here's a shot I took a while back with a 10D.. Note the halo around the
bright globes. This is the same effect as frankg experienced, only
in reverse.. The light is bright and the background is dark.

http://www.pbase.com/jim_townsend/image/49689066

> A few questions come to mind. How would you
> properly expose a pic like this? If you stop down enough to get the
> water better, won't you lose the boys face? Is the dynamic range of
> this picture just too much (i.e., more than 5 stops?)? Is fill flash a
> viable option here? Wouldn't you have to have one helluva flash unit to
> do much good in this situation? How would a histogram help in taking
> this picture?

It's a tough one.. This is one time a powerful external flash would
come in handy.

> Moving to the digital darkroom...
> What could you do to fix this pic? Is it saveable in RAW format? In
> JPEG?
> Seems like there could be an entire digital photo course just working
> with this image!

LOL.. I couldn't fix it.. Nobody said this digital photography is easy  

Archived from groups: rec.photo.digital (More info?)

Very puzzing. I am not a photography expert regarding the unique
issues of digital photo processing. I do note that the 'edge' follows
your nephew's outline, but it only partiall follows the outline of the
piling to his left...the edges of the piling are free from this effect
although it is bordering the bright area of the reflection from the
water. Also the white waistband bordering the water is free of this
edge. And the fishing reel top edge. This makes me think it is
something in the image processing software of the Rebel 300 image
processor which is getting overwhelmed by radically differences in
brightness, and this edge effect can be seen within the detail of the
top of the piling!

While you might not have applied any sharpening outside with Photoshop,
etc. I wonder if the camera's own Sharpening setting is what is behind
this effect?!?!

Archived from groups: rec.photo.digital (More info?)

On Fri, 23 Sep 2005 10:23:18 -0400, "frankg" <sorry@stoppingspam.com>
wrote:

> I have a great shot of my nephew fishing on a dock/pier that I took with my
>brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
>around the subject. The pic was taken at sunset, ambient light (low light
>levels) without fill flash and is backlit (semi-silhouette). The image was
>shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
>process. The 'outline' gets worse when I bring it into Photoshop and try to
>sharpen it. What is this and how can it be avoided ?
>
>I've noticed it on other digital images I shot too.
>thanks

I've noticed similar on my 350D with airshow photos. Blow out the
background and you get a serious fringe around any in-focus edges in
the foreground. My Canon 75-300 Mk2 does it terribly at 300mm, which
is why I have replaced it with a 300mm L lens.

What lens was this shot with?




--

Tim Hobbs

'58 Series 2 88" aka "Stig"
'03 Volvo V70

Archived from groups: rec.photo.digital (More info?)

>> I have a great shot of my nephew fishing on a dock/pier that I took with
>> my
>>brother's 6 MP Canon Digital Rebel. The main problem being a dark
>>'outline'
>>around the subject. The pic was taken at sunset, ambient light (low light
>>levels) without fill flash and is backlit (semi-silhouette). The image was
>>shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
>>process. The 'outline' gets worse when I bring it into Photoshop and try
>>to
>>sharpen it. What is this and how can it be avoided ?
>>
>>I've noticed it on other digital images I shot too.
>>thanks
>
> I've noticed similar on my 350D with airshow photos. Blow out the
> background and you get a serious fringe around any in-focus edges in
> the foreground. My Canon 75-300 Mk2 does it terribly at 300mm, which
> is why I have replaced it with a 300mm L lens.
>
> What lens was this shot with?
>
It was an 85mm/f1.8 - not an L lens but a decent quality for sure - or am I
sure ?
As i said above, it is overexposed with the sun kicking off the water - but
on the
original, when I run the Photoshop Info cursor over the hottest spots
they're still under 255.
Would this cause a dark 'outline', 'fringing', 'halo' ?

Archived from groups: rec.photo.digital (More info?)

wilt wrote:
> Very puzzing. I am not a photography expert regarding the unique
> issues of digital photo processing. I do note that the 'edge' follows
> your nephew's outline, but it only partiall follows the outline of the
> piling to his left...the edges of the piling are free from this effect
> although it is bordering the bright area of the reflection from the
> water. Also the white waistband bordering the water is free of this
> edge. And the fishing reel top edge. This makes me think it is
> something in the image processing software of the Rebel 300 image
> processor which is getting overwhelmed by radically differences in
> brightness, and this edge effect can be seen within the detail of the
> top of the piling!
>
> While you might not have applied any sharpening outside with Photoshop,
> etc. I wonder if the camera's own Sharpening setting is what is behind
> this effect?!?!

I'm a video engineer and that certainly looks like 'image enhancement'
(sharpening) to me. Look closely and you will see the same effect
around the top of his ear. The enhancement typically looks for fairly
rapid transitions, develops an 'S' curve and adds it to the original
signal. This shows up as the light side of the transition getting an
extra kick and the dark side getting a dark outline. The 'S' is based
on the magnitude of the transition so it gets larger when the original
transition is larger. Since the background is already at max level, you
don't see the boost in the white, only the cnhange in the dark area. If
you could duplicate the shot with no sharpening in the camera, I don't
believe you would see any outline. Its entirely possible that with 'no'
sharpening, there actually is a minimal amount always added regardless.
Flare and 'blooming' shows up as smearing of the transitions, not
outlines.

Glenn Gundlach

Archived from groups: rec.photo.digital (More info?)

In article <11j8h1r348m6i7d@news.supernews.com>,
Jim Townsend <not@real.address> wrote:

> salgud wrote:
>
> > Jim Townsend wrote:
>
> >> The background is extremely blown out...
> >>
> >> The fringe appears to be a flare caused by the grossly
> >> overexposed background bleeding over..
> >
> > Can you, Jim, or someone else, elaborate on this comment? I'm just
> > getting into digital photography (did a lot of film photograpy years
> > ago) and I'm curious.
>
> Flare is not uncommon where extremely bright areas meet dark areas.

It is not flare. It is either blooming or chromatic aberration.

This is flare:
http://www.ghostweb.com/lensflare.html

>
> I've read that this is caused by some of the strong charge in the
> light area bleeding over to adjacent sensor sites on the camera's
> sensor. The fact that lens glass is never optically perfect might
> exacerbate the problem.

That is what I understand as well.

>
> Here's a shot I took a while back with a 10D.. Note the halo around the
> bright globes. This is the same effect as frankg experienced, only
> in reverse.. The light is bright and the background is dark.
>
> http://www.pbase.com/jim_townsend/image/49689066

I would say that is a totally different effect.

>
> > A few questions come to mind. How would you
> > properly expose a pic like this? If you stop down enough to get the
> > water better, won't you lose the boys face? Is the dynamic range of
> > this picture just too much (i.e., more than 5 stops?)? Is fill flash a
> > viable option here? Wouldn't you have to have one helluva flash unit to
> > do much good in this situation? How would a histogram help in taking
> > this picture?
>
> It's a tough one.. This is one time a powerful external flash would
> come in handy.

There is no perfect exposure. Only correct ones. His exposure, to me, is
correct.

>
> > Moving to the digital darkroom...
> > What could you do to fix this pic? Is it saveable in RAW format? In
> > JPEG?
> > Seems like there could be an entire digital photo course just working
> > with this image!
>
> LOL.. I couldn't fix it.. Nobody said this digital photography is easy  

http://ray.cg.tuwien.ac.at/rft/Photography/TipsAndTrick...

--

Photographs by Christian Bonanno
http://home.nc.rr.com/christianbonanno/

Archived from groups: rec.photo.digital (More info?)

Christian Bonanno wrote:

> In article <11j8h1r348m6i7d@news.supernews.com>,
> Jim Townsend <not@real.address> wrote:

>> Flare is not uncommon where extremely bright areas meet dark areas.
>
> It is not flare. It is either blooming or chromatic aberration.

You're right.. Blooming is the word I should have used.. For some
reason 'flare' came to mind :-)

Archived from groups: rec.photo.digital (More info?)

In article <edVYe.13$Bi.29131@news20.bellglobal.com>,
"frankg" <sorry@stoppingspam.com> wrote:

> > Any way to offer an example, so that we are not blindly speculating,
> > and including the possiblity of demonic possession? <grin>
> >
>
> I have uploaded 3 files here http://www.frankgross.com/temp/
> one is the entire frame.
> another is cropped around the boy so you can see the 'dark outline'
> and a third is the the file up- res 'd in photoshop (bicubic smoother) 200%
> so you can better see the dark outline


I think it is Chromatic Aberration and it is fixable if you have
photoshop.

http://www.outdooreyes.com/photo26.php3
http://ray.cg.tuwien.ac.at/rft/Photography/TipsAndTrick...

Or it's "Blooming".

http://www.buy-n-shoot.com/photography-tips8.asp

"Blooming occurs when a group of photodiodes on an image sensor receive
more light than they can handle. The resulting electrical charge
overflows into adjacent photodiodes, which lose their ability to record
a signal that is proportional to the incoming light they receive. This
will produce an area in which the image data is corrupted."


But they both can be acting as well.

And it can be from the CMOS or the lens.

But you will notice the dark line nearly disappears at the lighter
portions of his hair.


Here's some more stuff:
http://www.photomacrography.net/photomacrography/Articl...
_abs.htm


--

Photographs by Christian Bonanno
http://home.nc.rr.com/christianbonanno/

Archived from groups: rec.photo.digital (More info?)

"frankg" <sorry@stoppingspam.com> wrote in message
news:8iUYe.1$Bi.59@news20.bellglobal.com...
> I have a great shot of my nephew fishing on a dock/pier that I took with
my
> brother's 6 MP Canon Digital Rebel. The main problem being a dark
'outline'
> around the subject. The pic was taken at sunset, ambient light (low light
> levels) without fill flash and is backlit (semi-silhouette). The image was
> shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> process. The 'outline' gets worse when I bring it into Photoshop and try
to
> sharpen it. What is this and how can it be avoided ?
>
> I've noticed it on other digital images I shot too.
> thanks


Looks like artefacting due to agressive in-camera sharpening to me. Here's
what I did to reduce it:

1) Using the magic wand (+16 sensitivity, I think) I masked all the bright
area around the boy.
2) Modify to expand the mask by +1
3) Copy via new layer
4) Select and erase all portions of the new layer except the dark outline
4b) Optional- apply a light Gaussian blur to layer.
5) Invert the layer and change mode to Overlay
6) Adjust new layer opacity
7) Flatten image

There are several other ways to deal with the outline, selective blurring,
Replace Color, etc. Once you've isolated the dark outline, you can go crazy
with correction experimentation.

Situations like this are why God made fill flash. With something like a
Sunpak 383 (GN=130) you can do slight fills up to 2 miles away. Well, that's
a bit of an exaggeration, but it really can reach out and touch a scene...

Archived from groups: rec.photo.digital (More info?)

In article <edOdnZ1rKMl5KqjeRVn-qA@comcast.com>,
"Paul H." <xxpaulhtck@zzcomcast.yynet> wrote:

> "frankg" <sorry@stoppingspam.com> wrote in message
> news:8iUYe.1$Bi.59@news20.bellglobal.com...
> > I have a great shot of my nephew fishing on a dock/pier that I took with
> my
> > brother's 6 MP Canon Digital Rebel. The main problem being a dark
> 'outline'
> > around the subject. The pic was taken at sunset, ambient light (low light
> > levels) without fill flash and is backlit (semi-silhouette). The image was
> > shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> > process. The 'outline' gets worse when I bring it into Photoshop and try
> to
> > sharpen it. What is this and how can it be avoided ?
> >
> > I've noticed it on other digital images I shot too.
> > thanks
>
>
> Looks like artefacting due to agressive in-camera sharpening to me. Here's
> what I did to reduce it:
>

That is not correct. If it was the case we would see it on all edges of
the shot.

It is blooming or chromatic aberration.

> 1) Using the magic wand (+16 sensitivity, I think) I masked all the bright
> area around the boy.
> 2) Modify to expand the mask by +1
> 3) Copy via new layer
> 4) Select and erase all portions of the new layer except the dark outline
> 4b) Optional- apply a light Gaussian blur to layer.
> 5) Invert the layer and change mode to Overlay
> 6) Adjust new layer opacity
> 7) Flatten image
>
> There are several other ways to deal with the outline, selective blurring,
> Replace Color, etc. Once you've isolated the dark outline, you can go crazy
> with correction experimentation.
>
> Situations like this are why God made fill flash. With something like a
> Sunpak 383 (GN=130) you can do slight fills up to 2 miles away. Well, that's
> a bit of an exaggeration, but it really can reach out and touch a scene...




--

Photographs by Christian Bonanno
http://christianbonanno.com/

Archived from groups: rec.photo.digital (More info?)

frankg wrote:
>
> I have a great shot of my nephew fishing on a dock/pier that I took with my
> brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
> around the subject. The pic was taken at sunset, ambient light (low light
> levels) without fill flash and is backlit (semi-silhouette). The image was
> shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> process. The 'outline' gets worse when I bring it into Photoshop and try to
> sharpen it. What is this and how can it be avoided ?
>
> I've noticed it on other digital images I shot too.
> thanks
>
> --
> =========

What RAW converter did you use to 'unpack' the RAW file? Too much
sharpening in the converter would cause this problem. I only use
Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
anything like your outlines on my shots. When I unpack I do not use any
sharpening at all, just color balance and exposure correction, and then
sharpen if necessary in Photoshop.

Colin D.

Archived from groups: rec.photo.digital (More info?)

In article <43366B49.987E6E91@killspam.127.0.0.1>,
Colin D <ColinD@killspam.127.0.0.1> wrote:

> frankg wrote:
> >
> > I have a great shot of my nephew fishing on a dock/pier that I took with my
> > brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
> > around the subject. The pic was taken at sunset, ambient light (low light
> > levels) without fill flash and is backlit (semi-silhouette). The image was
> > shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> > process. The 'outline' gets worse when I bring it into Photoshop and try to
> > sharpen it. What is this and how can it be avoided ?
> >
> > I've noticed it on other digital images I shot too.
> > thanks
> >
> > --
> > =========
>
> What RAW converter did you use to 'unpack' the RAW file? Too much
> sharpening in the converter would cause this problem. I only use
> Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
> anything like your outlines on my shots. When I unpack I do not use any
> sharpening at all, just color balance and exposure correction, and then
> sharpen if necessary in Photoshop.
>
> Colin D.


That is not correct. If it was the case we would see it on all edges of
the shot.

It is blooming or chromatic aberration.

--

Photographs by Christian Bonanno
http://christianbonanno.com/

Archived from groups: rec.photo.digital (More info?)

In article
<seewebpage-2F51D7.09530125092005@news3-ge0.southeast.rr.com>,
Christian Bonanno <seewebpage@mysig.com> wrote:

> > What RAW converter did you use to 'unpack' the RAW file? Too much
> > sharpening in the converter would cause this problem. I only use
> > Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
> > anything like your outlines on my shots. When I unpack I do not use any
> > sharpening at all, just color balance and exposure correction, and then
> > sharpen if necessary in Photoshop.
> >
> > Colin D.
>
>
> That is not correct. If it was the case we would see it on all edges of
> the shot.
>
> It is blooming or chromatic aberration.

You are correct.

Archived from groups: rec.photo.digital (More info?)

Christian Bonanno wrote:
>
> In article <43366B49.987E6E91@killspam.127.0.0.1>,
> Colin D <ColinD@killspam.127.0.0.1> wrote:
>
> > frankg wrote:
> > >
> > > I have a great shot of my nephew fishing on a dock/pier that I took with my
> > > brother's 6 MP Canon Digital Rebel. The main problem being a dark 'outline'
> > > around the subject. The pic was taken at sunset, ambient light (low light
> > > levels) without fill flash and is backlit (semi-silhouette). The image was
> > > shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> > > process. The 'outline' gets worse when I bring it into Photoshop and try to
> > > sharpen it. What is this and how can it be avoided ?
> > >
> > > I've noticed it on other digital images I shot too.
> > > thanks
> > >
> > > --
> > > =========
> >
> > What RAW converter did you use to 'unpack' the RAW file? Too much
> > sharpening in the converter would cause this problem. I only use
> > Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
> > anything like your outlines on my shots. When I unpack I do not use any
> > sharpening at all, just color balance and exposure correction, and then
> > sharpen if necessary in Photoshop.
> >
> > Colin D.
>
> That is not correct. If it was the case we would see it on all edges of
> the shot.
>
> It is blooming or chromatic aberration.
>
What, exactly, is not correct? I posed a question, and offered no
opinion, so there was nothing in my post that could be judged 'correct'
or 'not correct'.

Actually, it is you who is not correct. It is not blooming, or
chromatic abberation. It is excessive edge sharpening. I imported the
second image into Photoshop and pushed the size to the maximum, so each
individual pixel on my screen was about 4 millimetres wide. Adjacent to
the left side of the bollard on the wharf is the general tone of the
water, then a single column of pixels lighter than the water, then
another single column of pixels darker than the general tone of the
bollard, then the tone of the bollard itself. This shows very clearly
the effect of edge sharpening. Further, chromatic abberation shows
outlines of a *different* color than the surrounding images, e.g. purple
fringing on green foliage. The fringing in the image being discussed
shows no change in color at all. All the colors or tones in the fringe
are the same as the image, altered only in density.

As for not being on all edges, the visibility of edge sharpening, like
CA, depends on the contrast across the boundaries. You don't see CA on
all edges either, for the same reason.

Now, let's hear why you think it is CA.

Colin D.

Archived from groups: rec.photo.digital (More info?)

In article <433766EE.E423DC17@killspam.127.0.0.1>,
Colin D <ColinD@killspam.127.0.0.1> wrote:

> Christian Bonanno wrote:
> >
> > In article <43366B49.987E6E91@killspam.127.0.0.1>,
> > Colin D <ColinD@killspam.127.0.0.1> wrote:
> >
> > > frankg wrote:
> > > >
> > > > I have a great shot of my nephew fishing on a dock/pier that I took
> > > > with my
> > > > brother's 6 MP Canon Digital Rebel. The main problem being a dark
> > > > 'outline'
> > > > around the subject. The pic was taken at sunset, ambient light (low
> > > > light
> > > > levels) without fill flash and is backlit (semi-silhouette). The image
> > > > was
> > > > shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> > > > process. The 'outline' gets worse when I bring it into Photoshop and
> > > > try to
> > > > sharpen it. What is this and how can it be avoided ?
> > > >
> > > > I've noticed it on other digital images I shot too.
> > > > thanks
> > > >
> > > > --
> > > > =========
> > >
> > > What RAW converter did you use to 'unpack' the RAW file? Too much
> > > sharpening in the converter would cause this problem. I only use
> > > Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
> > > anything like your outlines on my shots. When I unpack I do not use any
> > > sharpening at all, just color balance and exposure correction, and then
> > > sharpen if necessary in Photoshop.
> > >
> > > Colin D.
> >
> > That is not correct. If it was the case we would see it on all edges of
> > the shot.
> >
> > It is blooming or chromatic aberration.
> >
> What, exactly, is not correct?


>I posed a question, and offered no
> opinion, so there was nothing in my post that could be judged 'correct'
> or 'not correct'.

You said "Too much sharpening in the converter would cause this
problem." I said that is not correct.

But I was wrong.

>
> Actually, it is you who is not correct. It is not blooming, or
> chromatic abberation. It is excessive edge sharpening.

You have changed it to "edge" sharpening which is incorrect. Besides,
the digital rebel does not do "edge" sharpening internally.

It is a sharpening halo caused by hard sharpening, you are right.

> I imported the
> second image into Photoshop and pushed the size to the maximum, so each
> individual pixel on my screen was about 4 millimetres wide. Adjacent to
> the left side of the bollard on the wharf is the general tone of the
> water, then a single column of pixels lighter than the water, then
> another single column of pixels darker than the general tone of the
> bollard, then the tone of the bollard itself. This shows very clearly
> the effect of edge sharpening. Further, chromatic abberation shows
> outlines of a *different* color than the surrounding images, e.g. purple
> fringing on green foliage.


> The fringing in the image being discussed
> shows no change in color at all. All the colors or tones in the fringe
> are the same as the image, altered only in density.
>
> As for not being on all edges, the visibility of edge sharpening, like
> CA, depends on the contrast across the boundaries. You don't see CA on
> all edges either, for the same reason.
>
> Now, let's hear why you think it is CA.

Corrected. Peace. Thanks.

>
> Colin D.




--

Photographs by Christian Bonanno
http://christianbonanno.com/

Archived from groups: rec.photo.digital (More info?)

Randall Ainsworth wrote:
>
> In article
> <seewebpage-2F51D7.09530125092005@news3-ge0.southeast.rr.com>,
> Christian Bonanno <seewebpage@mysig.com> wrote:
>
> > > What RAW converter did you use to 'unpack' the RAW file? Too much
> > > sharpening in the converter would cause this problem. I only use
> > > Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
> > > anything like your outlines on my shots. When I unpack I do not use any
> > > sharpening at all, just color balance and exposure correction, and then
> > > sharpen if necessary in Photoshop.
> > >
> > > Colin D.
> >
> >
> > That is not correct. If it was the case we would see it on all edges of
> > the shot.
> >
> > It is blooming or chromatic aberration.
>
> You are correct.

Who is, me or Christian? If you say Christian, then read my reply to
him, and explain also why you think it is CA.

Colin D.

Archived from groups: rec.photo.digital (More info?)

Christian Bonanno wrote:
>
> In article <433766EE.E423DC17@killspam.127.0.0.1>,
> Colin D <ColinD@killspam.127.0.0.1> wrote:
>
> > Christian Bonanno wrote:
> > >
> > > In article <43366B49.987E6E91@killspam.127.0.0.1>,
> > > Colin D <ColinD@killspam.127.0.0.1> wrote:
> > >
> > > > frankg wrote:
> > > > >
> > > > > I have a great shot of my nephew fishing on a dock/pier that I took
> > > > > with my
> > > > > brother's 6 MP Canon Digital Rebel. The main problem being a dark
> > > > > 'outline'
> > > > > around the subject. The pic was taken at sunset, ambient light (low
> > > > > light
> > > > > levels) without fill flash and is backlit (semi-silhouette). The image
> > > > > was
> > > > > shot as RAW and saved as 16 bit Tif with no sharpening etc in the RAW
> > > > > process. The 'outline' gets worse when I bring it into Photoshop and
> > > > > try to
> > > > > sharpen it. What is this and how can it be avoided ?
> > > > >
> > > > > I've noticed it on other digital images I shot too.
> > > > > thanks
> > > > >
> > > > > --
> > > > > =========
> > > >
> > > > What RAW converter did you use to 'unpack' the RAW file? Too much
> > > > sharpening in the converter would cause this problem. I only use
> > > > Canon's Zoombrowser for unpacking my 300D shots, and I've never seen
> > > > anything like your outlines on my shots. When I unpack I do not use any
> > > > sharpening at all, just color balance and exposure correction, and then
> > > > sharpen if necessary in Photoshop.
> > > >
> > > > Colin D.
> > >
> > > That is not correct. If it was the case we would see it on all edges of
> > > the shot.
> > >
> > > It is blooming or chromatic aberration.
> > >
> > What, exactly, is not correct?
>
> >I posed a question, and offered no
> > opinion, so there was nothing in my post that could be judged 'correct'
> > or 'not correct'.
>
> You said "Too much sharpening in the converter would cause this
> problem." I said that is not correct.
>
> But I was wrong.
>
> >
> > Actually, it is you who is not correct. It is not blooming, or
> > chromatic abberation. It is excessive edge sharpening.
>
> You have changed it to "edge" sharpening which is incorrect. Besides,
> the digital rebel does not do "edge" sharpening internally.
>
> It is a sharpening halo caused by hard sharpening, you are right.
>
<snip>

OK, nothing personal was intended in my post, sorry if it sounded that
way. Sharpening and edge sharpening are the same, since it is performed
by software looking for relatively abrupt density changes in the image,
and then adding contrast to those changes, so one can say that edges are
what is being enhanced.

By the way, the Rebel in RAW mode doesn't do any image manipulation, it
just stores the parameters along with the image without applying them.
However, in the various jpeg modes it does apply contrast and sharpening
to the image before it is saved - but then that image doesn't get put
through a converter.

In my experience with a Rebel/300D and various third-party converters, I
have noticed a variety of effects added to the image, including the OP's
problem, which is why, despite its clunky reputation, I stick with
Canon's Zoombrowser. This is the reason I asked what converter the OP
used - which he hasn't yet answered.

Colin D.