Interesting phenomenon/problem(?)

I was just looking at some negatives I just got back from the lab the other
day. They were shot on Ilford XP-2 at the Salton Sea, a salt lake in the
desert east of San Diego. I was shooting a silhouette against the setting
sun over the water with a 28-135 IS on a Canon 1n, and the flare was so
strong, it fogged the next frame! I'm not exaggerating, it even shows some
of the sun image on the interspace between frames! I've never seen anything
like it before, and it happened on two separate pairs of frames. The sun
was at the top of the frame, both times.
Has anyone else seen anything like this before, and is it indicative of a
problem, internally, with my camera?

--
Skip Middleton
http://www.shadowcatcherimagery.com

No problem, unless you spent too long looking through the viewfinder at the
time. This is halation, and it is not entirely preventable.

--
http://www.chapelhillnoir.com
home of The Camera-ist's Manifesto
The Improved Links Pages are at
http://www.chapelhillnoir.com/links/mlinks00.html
A sample chapter from my novel "Haight-Ashbury" is at
http://www.chapelhillnoir.com/writ/hait/hatitl.html
"Skip M" wrote in message
news:GMvZc.49424$bT1.2974@fed1read07...
I was just looking at some negatives I just got back from the lab the
other
day. They were shot on Ilford XP-2 at the Salton Sea, a salt lake in the
desert east of San Diego. I was shooting a silhouette against the setting
sun over the water with a 28-135 IS on a Canon 1n, and the flare was so
strong, it fogged the next frame! I'm not exaggerating, it even shows
some
of the sun image on the interspace between frames! I've never seen
anything
like it before, and it happened on two separate pairs of frames. The sun
was at the top of the frame, both times.
Has anyone else seen anything like this before, and is it indicative of a
problem, internally, with my camera?

--
Skip Middleton
http://www.shadowcatcherimagery.com

No problem, unless you spent too long looking through the viewfinder at the
time. This is halation, and it is not entirely preventable.

--
http://www.chapelhillnoir.com
home of The Camera-ist's Manifesto
The Improved Links Pages are at
http://www.chapelhillnoir.com/links/mlinks00.html
A sample chapter from my novel "Haight-Ashbury" is at
http://www.chapelhillnoir.com/writ/hait/hatitl.html
"Skip M" wrote in message
news:GMvZc.49424$bT1.2974@fed1read07...
I was just looking at some negatives I just got back from the lab the
other
day. They were shot on Ilford XP-2 at the Salton Sea, a salt lake in the
desert east of San Diego. I was shooting a silhouette against the setting
sun over the water with a 28-135 IS on a Canon 1n, and the flare was so
strong, it fogged the next frame! I'm not exaggerating, it even shows
some
of the sun image on the interspace between frames! I've never seen
anything
like it before, and it happened on two separate pairs of frames. The sun
was at the top of the frame, both times.
Has anyone else seen anything like this before, and is it indicative of a
problem, internally, with my camera?

--
Skip Middleton
http://www.shadowcatcherimagery.com

Tony Spadaro wrote:

No problem, unless you spent too long looking through the viewfinder at the
time. This is halation, and it is not entirely preventable.


Also indicative of poor internal baffling (yes, it is mostly preventable).

"Tony Spadaro" wrote in message
...
No problem, unless you spent too long looking through the viewfinder at
the
time. This is halation, and it is not entirely preventable.

Yep. To expand a little bit, it's flare from the film, not the lens or
anything else about the camera.

Halation is when the light is intense enough to pass completely through
the emulsion layers and bounce off of the acetate base, and in some cases
passes through the acetate base as well, bounces off the back side, and back
through again (much like the faint double reflections from a piece of
glass). In very extreme cases, you can even bounce light from the pressure
plate of the camera, and get a pattern of the dimples in the pressure plate.

This causes light scatter, and very often with B&W films (fewer emulsion
layers absorbing the light) can also cause distinct rings around point light
sources, because the light is focused for the front surface of the film, and
in passing through it actually defocuses enough to produce a ring. I suspect
there are other properties of the film at work too, since the rings are
distinct, not just fuzzy spots like you'd expect.

Basically, it's a result of extreme over-exposure, and this is to be
expected in any photo with the sun in the frame, unless your exposure is low
enough to get no other details *but* the sun, and you'd still probably need
some heavy filtering to accomplish this with most cameras. I see it all the
time in B&W with time-exposures at night that have streetlights in the
frame.

Most films have an anti-halation layer, but it's only so effective, and
B&W films suffer worse from halation because there's only one emulsion
layer, not three, and it has no dye in it. So less light gets absorbed by
the emulsion and is able to pass through.

This effect is also the reason IR films are supposed to be loaded in the
dark. They're a lot more sensitive and don't have this layer, so bright
light hitting the film can actually travel along the film base lengthwise
like fiber optics, fogging the hell out of the emulsion from behind.

Hope this helps,

- Al.


--
To reply, insert a dash between "wading" and "in".
Please excuse the changed format, I'm working remotely.

"Tony Spadaro" wrote in message
...
No problem, unless you spent too long looking through the viewfinder at
the
time. This is halation, and it is not entirely preventable.

Yep. To expand a little bit, it's flare from the film, not the lens or
anything else about the camera.

Halation is when the light is intense enough to pass completely through
the emulsion layers and bounce off of the acetate base, and in some cases
passes through the acetate base as well, bounces off the back side, and back
through again (much like the faint double reflections from a piece of
glass). In very extreme cases, you can even bounce light from the pressure
plate of the camera, and get a pattern of the dimples in the pressure plate.

This causes light scatter, and very often with B&W films (fewer emulsion
layers absorbing the light) can also cause distinct rings around point light
sources, because the light is focused for the front surface of the film, and
in passing through it actually defocuses enough to produce a ring. I suspect
there are other properties of the film at work too, since the rings are
distinct, not just fuzzy spots like you'd expect.

Basically, it's a result of extreme over-exposure, and this is to be
expected in any photo with the sun in the frame, unless your exposure is low
enough to get no other details *but* the sun, and you'd still probably need
some heavy filtering to accomplish this with most cameras. I see it all the
time in B&W with time-exposures at night that have streetlights in the
frame.

Most films have an anti-halation layer, but it's only so effective, and
B&W films suffer worse from halation because there's only one emulsion
layer, not three, and it has no dye in it. So less light gets absorbed by
the emulsion and is able to pass through.

This effect is also the reason IR films are supposed to be loaded in the
dark. They're a lot more sensitive and don't have this layer, so bright
light hitting the film can actually travel along the film base lengthwise
like fiber optics, fogging the hell out of the emulsion from behind.

Hope this helps,

- Al.


--
To reply, insert a dash between "wading" and "in".
Please excuse the changed format, I'm working remotely.

"Al Denelsbeck" wrote in message
...

"Tony Spadaro" wrote in message
...
No problem, unless you spent too long looking through the viewfinder at
the
time. This is halation, and it is not entirely preventable.

Yep. To expand a little bit, it's flare from the film, not the lens or
anything else about the camera.

Halation is when the light is intense enough to pass completely
through
the emulsion layers and bounce off of the acetate base, and in some cases
passes through the acetate base as well, bounces off the back side, and
back
through again (much like the faint double reflections from a piece of
glass). In very extreme cases, you can even bounce light from the pressure
plate of the camera, and get a pattern of the dimples in the pressure
plate.

This causes light scatter, and very often with B&W films (fewer
emulsion
layers absorbing the light) can also cause distinct rings around point
light
sources, because the light is focused for the front surface of the film,
and
in passing through it actually defocuses enough to produce a ring. I
suspect
there are other properties of the film at work too, since the rings are
distinct, not just fuzzy spots like you'd expect.

Basically, it's a result of extreme over-exposure, and this is to be
expected in any photo with the sun in the frame, unless your exposure is
low
enough to get no other details *but* the sun, and you'd still probably
need
some heavy filtering to accomplish this with most cameras. I see it all
the
time in B&W with time-exposures at night that have streetlights in the
frame.

Most films have an anti-halation layer, but it's only so effective,
and
B&W films suffer worse from halation because there's only one emulsion
layer, not three, and it has no dye in it. So less light gets absorbed by
the emulsion and is able to pass through.

This effect is also the reason IR films are supposed to be loaded in
the
dark. They're a lot more sensitive and don't have this layer, so bright
light hitting the film can actually travel along the film base lengthwise
like fiber optics, fogging the hell out of the emulsion from behind.

Hope this helps,

- Al.


--
To reply, insert a dash between "wading" and "in".
Please excuse the changed format, I'm working remotely.


Helps a lot, thanks, Tony and Al! I didn't thing of that, the plastic base
would act like a fiber optic light, and just run the light up the film for a
space. I'll remember that, and be more careful, next time...

--
Skip Middleton
http://www.shadowcatcherimagery.com

"Al Denelsbeck" wrote in message
...

"Tony Spadaro" wrote in message
...
No problem, unless you spent too long looking through the viewfinder at
the
time. This is halation, and it is not entirely preventable.

Yep. To expand a little bit, it's flare from the film, not the lens or
anything else about the camera.

Halation is when the light is intense enough to pass completely
through
the emulsion layers and bounce off of the acetate base, and in some cases
passes through the acetate base as well, bounces off the back side, and
back
through again (much like the faint double reflections from a piece of
glass). In very extreme cases, you can even bounce light from the pressure
plate of the camera, and get a pattern of the dimples in the pressure
plate.

This causes light scatter, and very often with B&W films (fewer
emulsion
layers absorbing the light) can also cause distinct rings around point
light
sources, because the light is focused for the front surface of the film,
and
in passing through it actually defocuses enough to produce a ring. I
suspect
there are other properties of the film at work too, since the rings are
distinct, not just fuzzy spots like you'd expect.

Basically, it's a result of extreme over-exposure, and this is to be
expected in any photo with the sun in the frame, unless your exposure is
low
enough to get no other details *but* the sun, and you'd still probably
need
some heavy filtering to accomplish this with most cameras. I see it all
the
time in B&W with time-exposures at night that have streetlights in the
frame.

Most films have an anti-halation layer, but it's only so effective,
and
B&W films suffer worse from halation because there's only one emulsion
layer, not three, and it has no dye in it. So less light gets absorbed by
the emulsion and is able to pass through.

This effect is also the reason IR films are supposed to be loaded in
the
dark. They're a lot more sensitive and don't have this layer, so bright
light hitting the film can actually travel along the film base lengthwise
like fiber optics, fogging the hell out of the emulsion from behind.

Hope this helps,

- Al.


--
To reply, insert a dash between "wading" and "in".
Please excuse the changed format, I'm working remotely.


Helps a lot, thanks, Tony and Al! I didn't thing of that, the plastic base
would act like a fiber optic light, and just run the light up the film for a
space. I'll remember that, and be more careful, next time...

--
Skip Middleton
http://www.shadowcatcherimagery.com

"Al Denelsbeck" wrote in message
...

"Tony Spadaro" wrote in message
...
No problem, unless you spent too long looking through the viewfinder at
the
time. This is halation, and it is not entirely preventable.

Yep. To expand a little bit, it's flare from the film, not the lens or
anything else about the camera.

Halation is when the light is intense enough to pass completely
through
the emulsion layers and bounce off of the acetate base, and in some cases
passes through the acetate base as well, bounces off the back side, and
back
through again (much like the faint double reflections from a piece of
glass). In very extreme cases, you can even bounce light from the pressure
plate of the camera, and get a pattern of the dimples in the pressure
plate.

This causes light scatter, and very often with B&W films (fewer
emulsion
layers absorbing the light) can also cause distinct rings around point
light
sources, because the light is focused for the front surface of the film,
and
in passing through it actually defocuses enough to produce a ring. I
suspect
there are other properties of the film at work too, since the rings are
distinct, not just fuzzy spots like you'd expect.

Basically, it's a result of extreme over-exposure, and this is to be
expected in any photo with the sun in the frame, unless your exposure is
low
enough to get no other details *but* the sun, and you'd still probably
need
some heavy filtering to accomplish this with most cameras. I see it all
the
time in B&W with time-exposures at night that have streetlights in the
frame.

Most films have an anti-halation layer, but it's only so effective,
and
B&W films suffer worse from halation because there's only one emulsion
layer, not three, and it has no dye in it. So less light gets absorbed by
the emulsion and is able to pass through.

This effect is also the reason IR films are supposed to be loaded in
the
dark. They're a lot more sensitive and don't have this layer, so bright
light hitting the film can actually travel along the film base lengthwise
like fiber optics, fogging the hell out of the emulsion from behind.

Hope this helps,

- Al.


--
To reply, insert a dash between "wading" and "in".
Please excuse the changed format, I'm working remotely.


Helps a lot, thanks, Tony and Al! I didn't thing of that, the plastic base
would act like a fiber optic light, and just run the light up the film for a
space. I'll remember that, and be more careful, next time...

--
Skip Middleton
http://www.shadowcatcherimagery.com