F717: exposure problem with long shutter values

Lisa Young said:

Lisa

Steve Cavigliano said:

Bingo said:

Daniel,

If we cannot trust the LCD, histogram doesn't do anything beyond
1/2s, how do you compose a picture if you don't want to use flash
and it's too dark for anything less than 1/2s? You won't be able to
tell if your image has correct exposure.

Click to expand...

Sure you will. Again, as many have mentioned in this thread, use
your meter. In manual mode select center-weighted metering. Then
select the aperture you'd like or the speed you'd like. Then just
adjust the other until the meter shows 0EV. This is a major
over-simplification, but it will give you the idea and get you
started. Worst case your image will look good in the center...lol

I mentioned bracketing and the using the histogram in my last post.
It was a general statement of how you should try to use all of the
cameras tools. I know it doesn't work at speeds slower than 1/2s
that's why I said when possible. Bracketing, on the other hand,
works at most speeds. Although, you'll have to do it manually, for
slow speed shots.

Since I'm new to

Lisa Young74699 said:

photography, I don't know how in general people control the
exposure without assistance from the camera, either film or
digital. Forgive my ignorance if the question sounds stupid.

Click to expand...

Take the shot then review it in the LCD. To see whether you over
exposed, under exposed, or hit it right on the head. Bearing in
mind that the LCD will show the image brighter than it actually is.
So if it looks perfect in the LCD, it's probably under exposed by
.7 - to 1 EV. Most of us who shoot at night like to take multiple
exposures. For one reason it improves the chance of getting that
"perfect" exposure. Other reasons are that you can blend and/or
stack these images to get less noise and more dynamic range.

Steve

--
http://www.pbase.com/slo2k
'If one really wishes to be master of an art, technical knowledge
of it is not enough. One has to transcend technique so that the
art becomes an 'artless art' growing out of the Unconscious.'

Click to expand...

--
My gallery: http://silvercharm.digitalphotochat.com/gallery
POTDs at DPC:
http://www.digitalphotocontest.com/profile.asp?pid=11986

Click to expand...

David Goldwasser said:

Here is one of my recent night shots (taken in the rain) As you
described steve I did takea few shots at different exposures and
with light trails to blend together.



Here are some earlier 707 shots.

Steve Cavigliano said:

Bingo said:

Daniel,

If we cannot trust the LCD, histogram doesn't do anything beyond
1/2s, how do you compose a picture if you don't want to use flash
and it's too dark for anything less than 1/2s? You won't be able to
tell if your image has correct exposure.

Click to expand...

Sure you will. Again, as many have mentioned in this thread, use
your meter. In manual mode select center-weighted metering. Then
select the aperture you'd like or the speed you'd like. Then just
adjust the other until the meter shows 0EV. This is a major
over-simplification, but it will give you the idea and get you
started. Worst case your image will look good in the center...lol

I mentioned bracketing and the using the histogram in my last post.
It was a general statement of how you should try to use all of the
cameras tools. I know it doesn't work at speeds slower than 1/2s
that's why I said when possible. Bracketing, on the other hand,
works at most speeds. Although, you'll have to do it manually, for
slow speed shots.

Since I'm new to

David Goldwasser said:

photography, I don't know how in general people control the
exposure without assistance from the camera, either film or
digital. Forgive my ignorance if the question sounds stupid.

Click to expand...

Take the shot then review it in the LCD. To see whether you over
exposed, under exposed, or hit it right on the head. Bearing in
mind that the LCD will show the image brighter than it actually is.
So if it looks perfect in the LCD, it's probably under exposed by
.7 - to 1 EV. Most of us who shoot at night like to take multiple
exposures. For one reason it improves the chance of getting that
"perfect" exposure. Other reasons are that you can blend and/or
stack these images to get less noise and more dynamic range.

Steve

--
http://www.pbase.com/slo2k
'If one really wishes to be master of an art, technical knowledge
of it is not enough. One has to transcend technique so that the
art becomes an 'artless art' growing out of the Unconscious.'

Click to expand...

--
David Goldwasser
http://www.inertia-llc.com

Click to expand...

Ulysses said:

Bingo said:

I found 100 is always select if auto mode is used. This seems
abnormal. Anyone else finds this is the case?

Click to expand...

Hmm... I just did a test using the full Auto mode (the green camera
Auto). The ISO it selected was ISO 320. That's what Sony cameras
have always done, generally selecting higher ISO than lower even if
light conditions seem bright.

Click to expand...

Member said:

Member said:

This is absolutely true. The histogram stopped moving after 1/2s
shutter speed is reached. Another thing I found is that when
shooting in low light condition, the aperture value satureated on
the 2.0 side instead of 8.0 side no matter what shutter speed you
select. I just think for the long shutter speed the camera doesn't
do the exposure calculation correctly. Beyond 1/2s you cannot use
histogram anymore. So we're out of luck...

Click to expand...

The results usually look okay, but if you're going for a particular
effect or need a specific aperture, the photographer is going to
have to step away from Auto. The one-size-fits-all mode is rarely
going to do everything you need.

--

Ulysses

Click to expand...

Bingo said:

Lisa Young said:

Lisa

Steve Cavigliano said:

Bingo said:

Daniel,

If we cannot trust the LCD, histogram doesn't do anything beyond
1/2s, how do you compose a picture if you don't want to use flash
and it's too dark for anything less than 1/2s? You won't be able to
tell if your image has correct exposure.

Click to expand...

Sure you will. Again, as many have mentioned in this thread, use
your meter. In manual mode select center-weighted metering. Then
select the aperture you'd like or the speed you'd like. Then just
adjust the other until the meter shows 0EV. This is a major
over-simplification, but it will give you the idea and get you
started. Worst case your image will look good in the center...lol

I mentioned bracketing and the using the histogram in my last post.
It was a general statement of how you should try to use all of the
cameras tools. I know it doesn't work at speeds slower than 1/2s
that's why I said when possible. Bracketing, on the other hand,
works at most speeds. Although, you'll have to do it manually, for
slow speed shots.

Since I'm new to

Bingo137199 said:

photography, I don't know how in general people control the
exposure without assistance from the camera, either film or
digital. Forgive my ignorance if the question sounds stupid.

Click to expand...

Take the shot then review it in the LCD. To see whether you over
exposed, under exposed, or hit it right on the head. Bearing in
mind that the LCD will show the image brighter than it actually is.
So if it looks perfect in the LCD, it's probably under exposed by
.7 - to 1 EV. Most of us who shoot at night like to take multiple
exposures. For one reason it improves the chance of getting that
"perfect" exposure. Other reasons are that you can blend and/or
stack these images to get less noise and more dynamic range.

Steve

--
http://www.pbase.com/slo2k
'If one really wishes to be master of an art, technical knowledge
of it is not enough. One has to transcend technique so that the
art becomes an 'artless art' growing out of the Unconscious.'

Click to expand...

--
My gallery: http://silvercharm.digitalphotochat.com/gallery
POTDs at DPC:
http://www.digitalphotocontest.com/profile.asp?pid=11986

Click to expand...

Click to expand...

David Goldwasser said:

Shay is the master of blending and you can find some good thread if
you search for "Shay Blending"

But here are some basics and background on how and why I use blending.

Why:
-Random noise is of course random, and the more shots you take and
blend together the contrast difference and appearnce of the noise
is greatly reduced, my guess is this what really goes on to some
degree in long expsoure noise reduction mode, althogh I'm sure more
advanced allogrithms, compairing odd hot pixels?)

-Increase of dynamic range. By taking two or more shots at
different exposures you can expand the effective dyanmic range of
the camera.

Camera issues:
Tripod is a must, ideally with wired remote, and also don't touch
zoom, or even focus. Auto maybe ok if subject very far away but I
like to focus and then set to manual. Focusing has very minor FOV
change which can blur your blened images (if they don't line up
your in for a lot of work, not even worth it)

Now if I'm just getting rid of noise I my goal is to overly each
photo so it has equal ammount of impact on the final image. I use
Photoshop to create multiple layers. Now to get each layer to have
equal effect I use numbers below for transparency setting, but if
its not exact won't matter if layers are all same exposure settings)

starting with back most layer
100% (opaque)
50
33
25
20
etc( 1/1 , 1/2 , 1/3 , 1/4 , 1/5)

Flatten and your done.

Now exposure braketing is a tougher issue. You can just blend
because in concept on one photo you have blown out the hilights so
dark areas are well captured, and on another shot you under exposed
the shadows so the bright areas are exposed well. For me it works
best if I also ahve a photo with mid range well exposed. I then
use the other two to enhance each end of the specturm. I have done
this so far without instructions and I need to write some down so
my brief description below may not be very good.

To start with I cut the contrast back on my mid range by pulling
the output in each end of the levels. Then I take my other two
shots (light and dark) and put them on new layers. To start with I
turn on my layer set for hilights. Then I need to select the dark
areas and mask them out. There are a number of ways such as
selecting by color and choosing "hilight" or out of gammut" I like
to make a gray scale copy of the layer, adjust the curves and the
use that as the mask (sorry can't explain more at the moment).
Then once I turn on the mask I adjust the cuves and levels of this
layer till it blends in well with the middle one. I repeate this
on the other end.

There are applications and plugins out there to automte this
process, but I have not been happy with the ones I have used. I'm
sure one day a great tool will come out that does this very
scientifically; ideally requiring some test shots from camera to
calibrate with. Progarm called HDRI Shop I think does something
like this.

Sorry if this is too long, I hope it made some sence and I do plan
on putting a tutorial togher at some point.

Bonus for reading all this (extra use for layering and blending)
When I'm shooting into the sun or its just out of frame and
throwing unwanted lens flare on the photo that I can't stop with a
hood or my hand out of frame I just take two shots. One where I
put my hand where it needs to be to get rid of the flare, even if
its covers part of my photo, and the other where I remove my hand
and let the lens flare go whtere they want, I'm only using this
second photo to patch where my hand was in the first. Camera must
be on full manual everything, and even with this I still feather
the edge of the mask on my patch layer.

Here is a link to quick sample I put up.
http://www.inertia-llc.com/sandbox/flash/

--
David Goldwasser
http://www.inertia-llc.com

Click to expand...

Bingo said:

Oh, I think we are talking about different things. I referred to
the ISO auto in SP mode, not the full auto mode. I always find that
100 is selected. I haven't tried the full auto mode yet...

Click to expand...

Ulysses said:

At least this part of it.

Okay, yes. That has always been the case, too. In the F707 and
other advanced Cyber-shots, when in S and A mode, if choosing an
Auto ISO, then it would always default to 100 unless you chose a
different ISO on your own.

Bingo said:

Oh, I think we are talking about different things. I referred to
the ISO auto in SP mode, not the full auto mode. I always find that
100 is selected. I haven't tried the full auto mode yet...

Click to expand...

--

Ulysses

Click to expand...