DSLR better for manual focus than P/S at night?

Hi Everyone,

I've been struggling a bit with pushing my P/S digital (Panasonic FZ30) to
long exposures at maximum zoom at night, taking 30-60 second exposures at
420 mm. My photographic objectives are typically 4-5 miles away, across a
body of water, and, when I view the structures I'm photographing with the
naked eye, the lights anchored to them (blast furnaces, factory buildings,
etc) are shimmering/twinkling pretty badly. I'm using manual focus, but my
results are mixed, and I frequently come home with 2/3 of my pictures
looking blurry, even though I'm focusing as tightly as possible using the
lcd display screen on the camera. I'm using a sturdy tripod, plus a cable
shutter release. I also let the tripod/camera "settle" for at least 30
seconds before starting an exposure. I've fixed the ISO at its minimum
value, and I'm working about two stops short of minimum f-ratio. When I
perform the manual focus, I'm iterating several times until the image I'm
viewing is as in focus as I can achieve in my limited experience, so I'm
wondering if I'm doing anything wrong, or if the camera and atmospheric
conditions are killing my focus. Some of my shots turn out pretty good,
taken only several minutes apart from unfocused shots, so I don't think it's
the camera or the atmospheric conditions (especially with water evaporation
on the bay between me and the buildings, nearly 3 miles wide, with me
shooting from the beach, so I'm at sea level). My question is, can a DSLR
offer more precise manual focus? For example, how about the Nikon D70 or
D200? How does one perform a manual focus with these cameras? Is one using
an lcd display screen, as I would do with the FZ30? I realize, with the
FZ30, I'm viewing the live image on the main camera sensor, which wouldn't
be the case with a DSLR. So how is manual focus done with a DSLR, and would
it be easier to achieve tighter focus with such a camera, at, say, 400 mm
zoom, than with my FZ30?

Thanks for any help,
Scott Speck

In article , Scott Speck
writes
Hi Everyone,

I've been struggling a bit with pushing my P/S digital (Panasonic FZ30) to
long exposures at maximum zoom at night, taking 30-60 second exposures at
420 mm. My photographic objectives are typically 4-5 miles away, across a
body of water, and, when I view the structures I'm photographing with the
naked eye, the lights anchored to them (blast furnaces, factory buildings,
etc) are shimmering/twinkling pretty badly.

That will cause your photographs to be blurred unless the exposure is
much less than the time it takes air-cells to move in the path.

I'm using manual focus, but my
results are mixed, and I frequently come home with 2/3 of my pictures
looking blurry, even though I'm focusing as tightly as possible using the
lcd display screen on the camera.

It is the same as the stellar scintillation (twinkle) effect with stars.

My question is, can a DSLR
offer more precise manual focus?

Yes, but focus is not the issue, you told us that it is
"shimmering/twinkling pretty badly".

For example, how about the Nikon D70 or
D200? How does one perform a manual focus with these cameras?

Look through the viewfinder.

Is one using
an lcd display screen,

No, the LCD is for reviewing the photograph after taking it, only one
DSLR about to hit the shops offers live LCD preview; from comments made
the viewfinders are variously dim or slow updating which would probably
make it unsuitable for your application.

as I would do with the FZ30? I realize, with the
FZ30, I'm viewing the live image on the main camera sensor, which wouldn't
be the case with a DSLR.

Whilst you are not viewing the image that is on the sensor (it's covered
by the shutter) you are viewing the image that will be on the sensor
when the shutter opens (I am ignoring subject movement).

So how is manual focus done with a DSLR, and would
it be easier to achieve tighter focus with such a camera, at, say, 400 mm
zoom, than with my FZ30?

Should be.

--
Ian G8ILZ

"Scott Speck" wrote in message
. ..
Hi Everyone,

I've been struggling a bit with pushing my P/S digital (Panasonic FZ30) to
long exposures at maximum zoom at night, taking 30-60 second exposures at
420 mm. My photographic objectives are typically 4-5 miles away, across a
body of water, and, when I view the structures I'm photographing with the
naked eye, the lights anchored to them (blast furnaces, factory buildings,
etc) are shimmering/twinkling pretty badly. I'm using manual focus, but
my results are mixed, and I frequently come home with 2/3 of my pictures
looking blurry, even though I'm focusing as tightly as possible using the
lcd display screen on the camera. I'm using a sturdy tripod, plus a cable
shutter release. I also let the tripod/camera "settle" for at least 30
seconds before starting an exposure. I've fixed the ISO at its minimum
value, and I'm working about two stops short of minimum f-ratio. When I
perform the manual focus, I'm iterating several times until the image I'm
viewing is as in focus as I can achieve in my limited experience, so I'm
wondering if I'm doing anything wrong, or if the camera and atmospheric
conditions are killing my focus. Some of my shots turn out pretty good,
taken only several minutes apart from unfocused shots, so I don't think
it's the camera or the atmospheric conditions (especially with water
evaporation on the bay between me and the buildings, nearly 3 miles wide,
with me shooting from the beach, so I'm at sea level). My question is,
can a DSLR offer more precise manual focus? For example, how about the
Nikon D70 or D200? How does one perform a manual focus with these
cameras? Is one using an lcd display screen, as I would do with the FZ30?
I realize, with the FZ30, I'm viewing the live image on the main camera
sensor, which wouldn't be the case with a DSLR. So how is manual focus
done with a DSLR, and would it be easier to achieve tighter focus with
such a camera, at, say, 400 mm zoom, than with my FZ30?

Thanks for any help,
Scott Speck

Just my two cents: Since what you are shooting is miles away, every shot is
going to be at infinity, so I'm not sure focus is the problem. It sounds
more like some atmospheric interference or camera movement, depending on the
shutter speeds you are using.

A DSLR can offer you better lenses, faster lenses, and options that may get
you better photos, but don't expect a miracle. If, as you say, 1/3rd of
your photos are good, those are pretty good numbers for any photographer.
It would probably be easier to diagnose the problem if we could see the
images, both good and bad.

Thanks for your thoughts. The problem with my camera is FINDING infinite
focus. The manual focus ring doesn't have a physical "stop" at infinity,
and I can keep rotating the ring beyond infinity, creating a cyclical focal
behavior.
-Scott


"Sheldon" wrote in message
. ..

"Scott Speck" wrote in message
. ..
Hi Everyone,

I've been struggling a bit with pushing my P/S digital (Panasonic FZ30)
to long exposures at maximum zoom at night, taking 30-60 second exposures
at 420 mm. My photographic objectives are typically 4-5 miles away,
across a body of water, and, when I view the structures I'm photographing
with the naked eye, the lights anchored to them (blast furnaces, factory
buildings, etc) are shimmering/twinkling pretty badly. I'm using manual
focus, but my results are mixed, and I frequently come home with 2/3 of
my pictures looking blurry, even though I'm focusing as tightly as
possible using the lcd display screen on the camera. I'm using a sturdy
tripod, plus a cable shutter release. I also let the tripod/camera
"settle" for at least 30 seconds before starting an exposure. I've fixed
the ISO at its minimum value, and I'm working about two stops short of
minimum f-ratio. When I perform the manual focus, I'm iterating several
times until the image I'm viewing is as in focus as I can achieve in my
limited experience, so I'm wondering if I'm doing anything wrong, or if
the camera and atmospheric conditions are killing my focus. Some of my
shots turn out pretty good, taken only several minutes apart from
unfocused shots, so I don't think it's the camera or the atmospheric
conditions (especially with water evaporation on the bay between me and
the buildings, nearly 3 miles wide, with me shooting from the beach, so
I'm at sea level). My question is, can a DSLR offer more precise manual
focus? For example, how about the Nikon D70 or D200? How does one
perform a manual focus with these cameras? Is one using an lcd display
screen, as I would do with the FZ30? I realize, with the FZ30, I'm
viewing the live image on the main camera sensor, which wouldn't be the
case with a DSLR. So how is manual focus done with a DSLR, and would it
be easier to achieve tighter focus with such a camera, at, say, 400 mm
zoom, than with my FZ30?

Thanks for any help,
Scott Speck

Just my two cents: Since what you are shooting is miles away, every shot
is going to be at infinity, so I'm not sure focus is the problem. It
sounds more like some atmospheric interference or camera movement,
depending on the shutter speeds you are using.

A DSLR can offer you better lenses, faster lenses, and options that may
get you better photos, but don't expect a miracle. If, as you say, 1/3rd
of your photos are good, those are pretty good numbers for any
photographer. It would probably be easier to diagnose the problem if we
could see the images, both good and bad.

Thanks Ed, I'm going to try that. I hope this works, since the manual focus
ring is, from what I know, electronically coupled to the camera, not
mechanically. So hopefully, if I make the mark at the correct spot, turn
the camera off, then on, spin the ring a few times, and then align the mark,
it will actually return to the same physical focus on the camera detector as
had previously been the case.

I have another question for you, too. If I set the focus at infinity,
should the image remain in focus as a function of zoom?

Thanks,
Scott


"Ed Ruf (REPLY to E-MAIL IN SIG!)" wrote in message
...
On Sun, 5 Feb 2006 05:53:09 -0500, in rec.photo.digital.slr-systems "Scott
Speck" wrote:

Thanks for your thoughts. The problem with my camera is FINDING infinite
focus. The manual focus ring doesn't have a physical "stop" at infinity,
and I can keep rotating the ring beyond infinity, creating a cyclical
focal
behavior.

So take a bit of time with your camera mounted on a tripod to find where
infinity focus is through trial and error and make a mark on the ring.

--
Ed Ruf Lifetime AMA# 344007 )
See images taken with my CP-990/5700 & D70 at
http://edwardgruf.com/Digital_Photog...ral/index.html

Ed, I think I've figured out what to do, because the manual focus ring is
not hard-coupled to the focusing process. For example, if I set the ring to
achieve proper manual focus at infinity, then switch to autofocus and focus
on something closeby, the manual focus ring doesn't move during the
autofocus process. As a result, if I then switch BACK to manual focus, I'm
out of focus for infinity, but my focus ring is still at the original
position that allowed the camera to BE at focus at infinity. I've therefore
figured out a couple options that should work, and I'll test them tonight:

1) Autofocus the camera on a distant object (infinity) during the day, when
the camera's AF is really good at locking a nice sharp focus. Then, switch
to manual focus and don't touch (or somehow anchor) the manual focus ring
from being able to turn. When I re-power the camera in manual focus, it'll
still be set at infinity.

2) my camera has a "starry sky mode", which, I believe causes the camera to
move to infinite focus. I could take a frame (in AF mode) in starry sky
mode, and then switch out of starry sky and back to manual focus. Then I
would refrain from touching the manual focus ring. I should stay at
infinity, in this case. This might be better than option 1, since I could
re-achieve infinite focus in low light even if I accidentally moved the
manual focus ring (as might happen with method 1).

I also switched OFF anti-shake, since the manual warns AGAINST using
anti-shake for long exposures. I thinks this might have been causing some
of the bizarre optical effects I was seeing (not just being out of focus,
but bizarre "doubling" or "tripling" of some images, despite no camera
motion). I'll keep ISO at 80 (minimum).

With all of this in place, I think I'll be able to get better results.

Thanks again,
Scott

----- Original Message -----
From: "Ed Ruf (REPLY to E-MAIL IN SIG!)"
Newsgroups: rec.photo.digital.slr-systems
Sent: Sunday, February 05, 2006 10:14 AM
Subject: DSLR better for manual focus than P/S at night?


On Sun, 5 Feb 2006 09:00:57 -0500, in rec.photo.digital.slr-systems "Scott
Speck" wrote:

Thanks Ed, I'm going to try that. I hope this works, since the manual
focus
ring is, from what I know, electronically coupled to the camera, not
mechanically. So hopefully, if I make the mark at the correct spot, turn
the camera off, then on, spin the ring a few times, and then align the
mark,
it will actually return to the same physical focus on the camera detector
as
had previously been the case.

I have another question for you, too. If I set the focus at infinity,
should the image remain in focus as a function of zoom?

Depends on the lens design. You could try asking tech support or try it
yourself at the extreme ends of the zoom.
--
Ed Ruf Lifetime AMA# 344007 )
See images taken with my CP-990/5700 & D70 at
http://edwardgruf.com/Digital_Photog...ral/index.html

Scott Speck wrote:

value, and I'm working about two stops short of minimum f-ratio. When I
perform the manual focus, I'm iterating several times until the image I'm
viewing is as in focus as I can achieve in my limited experience, so I'm
wondering if I'm doing anything wrong, or if the camera and atmospheric
conditions are killing my focus.

At that range,the focus should be set to infinity. Set it there, and
regardelss of what you "see" leave it there.


--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.

On Sun, 5 Feb 2006 05:53:09 -0500, "Scott Speck"
wrote:

Thanks for your thoughts. The problem with my camera is FINDING infinite
focus. The manual focus ring doesn't have a physical "stop" at infinity,
and I can keep rotating the ring beyond infinity, creating a cyclical focal
behavior.
-Scott
You are likely to find it difficult under certain circumstances
solely owing to atmospheric (air density) changes. At 400mm,
you are in essense magnifying the turbulence by about 8x
relative to what your eye sees. That rippling effect above a
BBQ you see with your eyes is what telephoto lenses make more
apparent. The larger the front element of the telephoto lens
(assuming you are using it wide open) the greater the problem.
Magnification makes it more apparent as well.
This is why (especially in daytime due to heatwaves) you are limited
in the amount of detail that any lens can show over long distances
where the air blanket and irregularies are deep. This is also why
testing lenses over long distances is problematic.
The steadiest conditions unfortunately coincide with things like
high moisture content and fog which themselves attenuate detail at
distance.
-Rich

On Sun, 05 Feb 2006 11:42:54 -0500, Alan Browne
wrote:

Scott Speck wrote:

value, and I'm working about two stops short of minimum f-ratio. When I
perform the manual focus, I'm iterating several times until the image I'm
viewing is as in focus as I can achieve in my limited experience, so I'm
wondering if I'm doing anything wrong, or if the camera and atmospheric
conditions are killing my focus.

At that range,the focus should be set to infinity. Set it there, and
regardelss of what you "see" leave it there.

Or, if the lens is marked incorrectly (being able to turn the ring
beyond infinity is sometimes used to compensate for thermal
expansion and contraction of the lens and it's housing) try shooting
at tiny increments before and after to see how it effects the final
result.
-Rich

"Scott Speck" wrote in message
...
Thanks for your thoughts. The problem with my camera is FINDING infinite
focus. The manual focus ring doesn't have a physical "stop" at infinity,
and I can keep rotating the ring beyond infinity, creating a cyclical
focal behavior.
-Scott

My camera is like this. There should be an infinity symbol on the focus
ring. The problem is that some manufactuturers have found that because of
zoom and temperature issues they can no longer put a stop at infinity, so it
leaves you having to find it yourself. I just use the symbol, and unless
you are shooting wide open, if you stop down a couple of stops you should be
well in the ball park. As a matter of fact, if you are not using a 1.8 or
2.8 lens wide open, just using that infinity symbol should be enough.
Personally, I hate the focus rings on most autofocus lenses. The
manufacturer's forgot that many of us still like to shoot in manual mode now
and then. This is where a DSLR might pay off, as you can use lenses made
for 35mm cameras with all the manual controls that go along with them.