What exactly is the issue with low light focus?

Stefan Ichim

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I've noticed low light focus being an issue, but when is it an issue?

Do low light focus instances (thus the good or bad behavior of a certain camera) also include the flashes that the camera would fire most of the time to assist its focus? I mean, does low light focus mean ALL instances of low light focus, including flash aided focus, for pictures that are going to be taken with flash?

My common sense (and bit of photography experience) says no. I mean, I have Canon Rebel 2000, beginner's SLR, and it is still able to focus most of the time even in pitch black, provided it flashes a couple of times. I tend to believe that it is the same with digitals (why not?) and then the issue is about flashless focusing for flashless pictures. Am I right? But then, is that such a big issue? How good can a flashless picture be if there is not even enough light to focus? And how long the exposure, thus the blur from shake? You would need a tripod and a steady subject, but how often does that occur to make it such a big issue? and if it does occur, than you probably have enough time to manually focus anyway (I am imagining a group of people posing, or some macro picture, but I still can't see why not to use the flash). Of course, there is also the case when there is not even enough light to manually focus (you just can't see) and than what do you do?

I would very much appreciate your comments, along with exemples (pictures and/or stories) of cases explaining why this low light focus is an issue. If it is possible for the cameras in question to be either Minolta Dimage 7i (apparently very good at the task), Fuji 602z (apparently very bad at it) or Olympus C-730 (not really any information about the particular performance in low light AF), it would be even better. I've gone too far, please forgive me... :)

Thank you very much,

Stefan

Thank you very much,

Stefan
 
I've noticed low light focus being an issue, but when is it an issue?
Do low light focus instances (thus the good or bad behavior of a
certain camera) also include the flashes that the camera would fire
most of the time to assist its focus? I mean, does low light focus
mean ALL instances of low light focus, including flash aided focus,

for pictures that are going to be taken with flash? I mean when a camera is said that it behaves poorly for low light focus, does it mean it's not helping itself with the flash and it's focusing bad without it, or that it is helping itself but it still focuses badly, or just that if I refuse it's helping itself with the flash, it will focus badly?
My common sense (and bit of photography experience) says no. I
mean, I have Canon Rebel 2000, beginner's SLR, and it is still able
to focus most of the time even in pitch black, provided it flashes
a couple of times. I tend to believe that it is the same with
digitals (why not?) and then the issue is about flashless focusing
for flashless pictures. Am I right? But then, is that such a big
issue? How good can a flashless picture be if there is not even
enough light to focus? And how long the exposure, thus the blur
from shake? You would need a tripod and a steady subject, but how
often does that occur to make it such a big issue? and if it does
occur, than you probably have enough time to manually focus anyway
(I am imagining a group of people posing, or some macro picture,
but I still can't see why not to use the flash). Of course, there
is also the case when there is not even enough light to manually
focus (you just can't see) and than what do you do?
I would very much appreciate your comments, along with exemples
(pictures and/or stories) of cases explaining why this low light
focus is an issue. If it is possible for the cameras in question to
be either Minolta Dimage 7i (apparently very good at the task),
Fuji 602z (apparently very bad at it) or Olympus C-730 (not really
any information about the particular performance in low light AF),
it would be even better. I've gone too far, please forgive me... :)

Thank you very much,

Stefan

Thank you very much,

Stefan
 
== Flash here ==

Stefan, this is a good question but to me it is one of the biggest strengths or weaknesses of a digital camera. I just bought a Sony F717 5-megapixel over a Nikon CP5700 because Nikon continually ignores this weakness in their design... NO low light assist and relatively slow lens. I have a Nikon CP995 3-megapixel (beautiful imaging) and an Olympus C2100-UZ, 2 megapixels. Guess which of the two I use more? The Uzi, because it focusses fast, and in low light, it turns on a red AF assist. Snap! Very fast.

It is very frustrating to wait for a camera to find sharp focus in low light. The opportunity may have passed before the shutter goes off.

I hope this helps! This is my first reply on this forum.

== Flash from NH ==
I've noticed low light focus being an issue, but when is it an issue?
Do low light focus instances (thus the good or bad behavior of a
certain camera) also include the flashes that the camera would fire
most of the time to assist its focus? I mean, does low light focus
mean ALL instances of low light focus, including flash aided focus,
for pictures that are going to be taken with flash?
My common sense (and bit of photography experience) says no. I
mean, I have Canon Rebel 2000, beginner's SLR, and it is still able
to focus most of the time even in pitch black, provided it flashes
a couple of times. I tend to believe that it is the same with
digitals (why not?) and then the issue is about flashless focusing
for flashless pictures. Am I right? But then, is that such a big
issue? How good can a flashless picture be if there is not even
enough light to focus? And how long the exposure, thus the blur
from shake? You would need a tripod and a steady subject, but how
often does that occur to make it such a big issue? and if it does
occur, than you probably have enough time to manually focus anyway
(I am imagining a group of people posing, or some macro picture,
but I still can't see why not to use the flash). Of course, there
is also the case when there is not even enough light to manually
focus (you just can't see) and than what do you do?
I would very much appreciate your comments, along with exemples
(pictures and/or stories) of cases explaining why this low light
focus is an issue. If it is possible for the cameras in question to
be either Minolta Dimage 7i (apparently very good at the task),
Fuji 602z (apparently very bad at it) or Olympus C-730 (not really
any information about the particular performance in low light AF),
it would be even better. I've gone too far, please forgive me... :)

Thank you very much,

Stefan

Thank you very much,

Stefan
 
Low light focus problems do apply to flash photos. The preflash is used to set exposure, not focus. If the camera can't focus, you'll get a well exposed blur.

Good point about non-flash low light shots. You can use manual focus by distance, since you can't be in too much of a hurry.
I've noticed low light focus being an issue, but when is it an issue?
Do low light focus instances (thus the good or bad behavior of a
certain camera) also include the flashes that the camera would fire
most of the time to assist its focus? I mean, does low light focus
mean ALL instances of low light focus, including flash aided focus,

for pictures that are going to be taken with flash? I mean when a camera is said that it behaves poorly for low light focus, does it mean it's not helping itself with the flash and it's focusing bad without it, or that it is helping itself but it still focuses badly, or just that if I refuse it's helping itself with the flash, it will focus badly?
My common sense (and bit of photography experience) says no. I
mean, I have Canon Rebel 2000, beginner's SLR, and it is still able
to focus most of the time even in pitch black, provided it flashes
a couple of times. I tend to believe that it is the same with
digitals (why not?) and then the issue is about flashless focusing
for flashless pictures. Am I right? But then, is that such a big
issue? How good can a flashless picture be if there is not even
enough light to focus? And how long the exposure, thus the blur
from shake? You would need a tripod and a steady subject, but how
often does that occur to make it such a big issue? and if it does
occur, than you probably have enough time to manually focus anyway
(I am imagining a group of people posing, or some macro picture,
but I still can't see why not to use the flash). Of course, there
is also the case when there is not even enough light to manually
focus (you just can't see) and than what do you do?
I would very much appreciate your comments, along with exemples
(pictures and/or stories) of cases explaining why this low light
focus is an issue. If it is possible for the cameras in question to
be either Minolta Dimage 7i (apparently very good at the task),
Fuji 602z (apparently very bad at it) or Olympus C-730 (not really
any information about the particular performance in low light AF),
it would be even better. I've gone too far, please forgive me... :)

Thank you very much,

Stefan

Thank you very much,

Stefan
 
you are trying to shoot any concert or theatrical show. Flash is almost never allowed and the focus assist light is not allowed either. These shows are usually rather fast paced and low light so it is hard to manual focus and keep up. I find that I am often trying to let the camera track focus until just the moment when it appears the subject will be staying still enough to get a clean shot with long exposures, If the camera did not autofocus in low light it would make my life that much harder.
Brian
 
Low light focus problems do apply to flash photos. The preflash is
used to set exposure, not focus. If the camera can't focus, you'll
get a well exposed blur.
Then this is a HUGE difference between SLR and digital! I just tested my SLR to make sure: In a very dark room it fired the flash and perfectly focused in less than a second. It does use flash for foscusing and I am very surprised that digitals cameras don't why would that be?
Are you sure?

Thanks,

Stefan
Good point about non-flash low light shots. You can use manual
focus by distance, since you can't be in too much of a hurry.
I've noticed low light focus being an issue, but when is it an issue?
Do low light focus instances (thus the good or bad behavior of a
certain camera) also include the flashes that the camera would fire
most of the time to assist its focus? I mean, does low light focus
mean ALL instances of low light focus, including flash aided focus,

for pictures that are going to be taken with flash? I mean when a camera is said that it behaves poorly for low light focus, does it mean it's not helping itself with the flash and it's focusing bad without it, or that it is helping itself but it still focuses badly, or just that if I refuse it's helping itself with the flash, it will focus badly?
My common sense (and bit of photography experience) says no. I
mean, I have Canon Rebel 2000, beginner's SLR, and it is still able
to focus most of the time even in pitch black, provided it flashes
a couple of times. I tend to believe that it is the same with
digitals (why not?) and then the issue is about flashless focusing
for flashless pictures. Am I right? But then, is that such a big
issue? How good can a flashless picture be if there is not even
enough light to focus? And how long the exposure, thus the blur
from shake? You would need a tripod and a steady subject, but how
often does that occur to make it such a big issue? and if it does
occur, than you probably have enough time to manually focus anyway
(I am imagining a group of people posing, or some macro picture,
but I still can't see why not to use the flash). Of course, there
is also the case when there is not even enough light to manually
focus (you just can't see) and than what do you do?
I would very much appreciate your comments, along with exemples
(pictures and/or stories) of cases explaining why this low light
focus is an issue. If it is possible for the cameras in question to
be either Minolta Dimage 7i (apparently very good at the task),
Fuji 602z (apparently very bad at it) or Olympus C-730 (not really
any information about the particular performance in low light AF),
it would be even better. I've gone too far, please forgive me... :)

Thank you very much,

Stefan

Thank you very much,

Stefan
 
Well, I agree that low light focus can be a problem, but I would think that for a concert or theatrical show it would not be a big deal as you have plenty of time to setup and the subject stays at a relatively constant distance (unless you are photographing the crowd). It is a bigger problem trying to take pictures of people or other moving subjects, as you can easily loose the moment.

Unfortunately, I'm speaking of experience ...

y.
you are trying to shoot any concert or theatrical show. Flash is
almost never allowed and the focus assist light is not allowed
either. These shows are usually rather fast paced and low light so
it is hard to manual focus and keep up. I find that I am often
trying to let the camera track focus until just the moment when it
appears the subject will be staying still enough to get a clean
shot with long exposures, If the camera did not autofocus in low
light it would make my life that much harder.
Brian
 
Low light focus problems do apply to flash photos. The preflash is
used to set exposure, not focus. If the camera can't focus, you'll
get a well exposed blur.
Then this is a HUGE difference between SLR and digital! I just
tested my SLR to make sure: In a very dark room it fired the flash
and perfectly focused in less than a second. It does use flash for
foscusing and I am very surprised that digitals cameras don't why
would that be?
Are you sure?
I don't believe that the flash is used for focusing your SLR either. At least not the flash you see. The flash lasts less than 1/1000 second (even if it fires twice) which isn't enough time for any camera to focus. However. film cameras or their flashes do have a "focus assist light" which is turned on to help focus the scene in dim light. That light is usually infrared, I believe, and not visible as a bright light. If you see it at all, it would be red. If it isn't infrared, it would have to be a bright LED in order to stay on long enough to achieve focus. Having said all this, one of the complaints about most digitals which accept external flashes is that they don't use the focus assist which is on the flash unit. I'm not sure, but I suspect that this might be because, at least in the case of the D7i, there is an an infrared blocking filter built into the camera. So the focus assist wouldn't work anyway.

Most of the above is based on reading I've done. If I'm out to lunch on any of this, I, too, would appreciate enlightenment from one of the experts on this forum.

Dewdrop
 
Back to that rebel...if you look at a canon autofus flash you will notice the big red plastic bit. Underneath most good flashes are often 2 infared beams that project a red light grid pattern at the subject for focus....often up to 30 feet..it sometimes looks like a Terminator movie scene :)

My piece of junk flash has a red plastic area for decoration, whick is fine as i use it for a fill flash on a light stand with umbrella.. My "good" flash has the 'brain" and the "eyes" to focus in absolute darkness...or close enough

If im doing a photo job which may include corporate mingles at hotel dinners its really dark and you need to capture awards quickly. There is no way i could do so many consistant shots without my speedlight.(if your drunk at a party try focusing without an external flash)

with manual focus pack a flash-light :).....

with digitals you often just have to trust them and wrestle them into submission if they try to act naughty...some with sophisticated flash options dont use the infared beam feature as it isnt coupled for some reason. (price point)

play with slow speed sync and + - flash if you have the option, and dont shoot long lenses after to much coffee

d
 
I agree that concerts can sometimes be a touch easier, plus they are often brighter but as far as theatre is concerned I have not meet many directors that like having people standing still unless it is a point in the script that it is needed for people to be still. Most actors are moving constantly when on stage, maybe not very far but they are moving, and the moment can last merely seconds when they are still enough to get a pic of. of the roughly 350 shows I have worked as a stagehand I can think of maybe 5 that the actors where not always moving. I do only shot during live performances though so maybe that could be the difference.
Unfortunately, I'm speaking of experience ...

y.
you are trying to shoot any concert or theatrical show. Flash is
almost never allowed and the focus assist light is not allowed
either. These shows are usually rather fast paced and low light so
it is hard to manual focus and keep up. I find that I am often
trying to let the camera track focus until just the moment when it
appears the subject will be staying still enough to get a clean
shot with long exposures, If the camera did not autofocus in low
light it would make my life that much harder.
Brian
 
Low light focus problems do apply to flash photos. The preflash is
used to set exposure, not focus. If the camera can't focus, you'll
get a well exposed blur.
Then this is a HUGE difference between SLR and digital! I just
tested my SLR to make sure: In a very dark room it fired the flash
and perfectly focused in less than a second. It does use flash for
foscusing and I am very surprised that digitals cameras don't why
would that be?
Are you sure?
I don't believe that the flash is used for focusing your SLR
either. At least not the flash you see. The flash lasts less than
1/1000 second (even if it fires twice) which isn't enough time for
any camera to focus. However. film cameras or their flashes do
have a "focus assist light" which is turned on to help focus the
scene in dim light. That light is usually infrared, I believe, and
not visible as a bright light. If you see it at all, it would be
red. If it isn't infrared, it would have to be a bright LED in
order to stay on long enough to achieve focus. Having said all
this, one of the complaints about most digitals which accept
external flashes is that they don't use the focus assist which is
on the flash unit. I'm not sure, but I suspect that this might be
because, at least in the case of the D7i, there is an an infrared
blocking filter built into the camera. So the focus assist
wouldn't work anyway.

Most of the above is based on reading I've done. If I'm out to
lunch on any of this, I, too, would appreciate enlightenment from
one of the experts on this forum.

Dewdrop
Well, I am sorry to say, but it seems to me that the reading you did was more or less wrong, at least for the case of my Canon Rebel 2000. I do not have an external flash. All the time I was only talking about the built-in flash. Also, the camera does not have any infrared LED or anything like that. I was very careful when checking it. It does have a normal light, a small LED, aside from the flash, that is suppoesd to be used for red eye reduction. At first it was turned on while flashing and successfully focusing. I covered it with my finger and there was no change in result: the camera was still focusing in pitch black using its built in flash (and I mean focusing, not metering). Further more, I turned the red-eye reduction off, and indeed, the small LED stopped lighting. The camera is still focusing the same. The only conclusion I can arrive to is that indeed, Canon Rebel 2000 DOES use the the built in flash, and ONLY the flash to focus even in deep darkness, and sucessfully does so. Yet, it is Canon's beginner SLR, so am I to believe that the same thing doesn't happen with fairly advanced digital cameras?

Please let me know what you think,

Thank you,

Stefan
 
According to the specifications page for the Canon Rebell 2000 on the Canon website, the 2000 does have an AF assist beam, as quoted from the page:

"AF-assist Beam: Automatically emitted when necessary and aimed at the area covered by the active focus point."

This would not be the flash. Surely this is covered in your owner's manual.

The principle is exactly the same with digital cameras. The ones with AF assist lamp focus well in the dark, the ones without don't. The Olympus C-2100UZ example was spot on because its AF assist lamp allows it to snap into focus rather quickly in the dark.

Rick
Low light focus problems do apply to flash photos. The preflash is
used to set exposure, not focus. If the camera can't focus, you'll
get a well exposed blur.
Then this is a HUGE difference between SLR and digital! I just
tested my SLR to make sure: In a very dark room it fired the flash
and perfectly focused in less than a second. It does use flash for
foscusing and I am very surprised that digitals cameras don't why
would that be?
Are you sure?

Thanks,

Stefan
 
According to the specifications page for the Canon Rebell 2000 on
the Canon website, the 2000 does have an AF assist beam, as
quoted from the page:
Now that makes sense to me, but I don't think that Stefan believes it. I suppose it's possible to use the flash if the focus method was to use the flash to somehow measure the camera to subject distance and then set the focus before firing the main flash. The double flash, though, is more likely a preflash to set the exposure, just like digital. If, on the other hand, the flash is the focus assist, I'd like to know how an ordinary electonic falsh can maintain a light output long enough to set the focus. Flashes work by discharging a capicator though the gas in the flash lamp. This discarge takes only a very short time. So I can't imagine how it could remain on long enough to focus the camera let alone have enough energy left to expose the image. In any case, since digital cameras work by adjusting for maximum contrast, only a steady focus assist lamp would be of any use.

Dewdrop
 
According to the specifications page for the Canon Rebell 2000 on
the Canon website, the 2000 does have an AF assist beam, as
quoted from the page:
Now that makes sense to me, but I don't think that Stefan believes
it. I suppose it's possible to use the flash if the focus method
was to use the flash to somehow measure the camera to subject
distance and then set the focus before firing the main flash. The
double flash, though, is more likely a preflash to set the
exposure, just like digital. If, on the other hand, the flash is
the focus assist, I'd like to know how an ordinary electonic falsh
can maintain a light output long enough to set the focus. Flashes
work by discharging a capicator though the gas in the flash lamp.
This discarge takes only a very short time. So I can't imagine how
it could remain on long enough to focus the camera let alone have
enough energy left to expose the image. In any case, since digital
cameras work by adjusting for maximum contrast, only a steady focus
assist lamp would be of any use.

Dewdrop
You are right, I can't really believe it... I am pretty handy with devices in general, I would say, and I've bee looking very thorughly at the camera. There is nothing else than the flash (or the red eye reduction little led, that I checked not to be responsible) that could emmit any kind of light. Also, the camera has a night portret mode, in which it uses the built in flas as a lantern (it stays on, although obviously not at full strength, for several good seconds). So they must have overcome the fast flash problem somehow (probably an additional basic light bulb). However, what it is doing is indeed when focusing is indeed flashes not a continous light.

Anyway, I decided to take the matter into my own hands, and after the guys at Ritz camera assured me that the camera is returnable for a full refund within 10 days, I bought a Fuji 602z today. The first thing I wanted to check was obviously the low light focus, what it is trying and what is it managing to do. The focus is almost nonexistant! It really needs A LOT of light to focus. and it would not use the flash, even though I actually tried to make it do so (I am talking about focusing, it does use flash for the picture). Also, the applauded-by-some "super-fast" good light focus is not that fast at all. There is a lot of lag somewhere along the way even with prefocus. I could not get one single picture the I wanted, it always came up something else, since there was no way to tell when the picture will actually be taken. I know that it is the advantage of digital that you can just check the picture, delete it and take another one. But it was just too much russian rouletting fo me. It would also not use the flas in supermacro mode (I guess it would be useless thanks to the huge lens barrel). On a purely personal oppinion: I find the grip huge, not necesarily unconfortable, but too big, as well as the camera overall. What can I say, than that I am really really disappointed by the camera. It is going right back first thing tomorrow morning!

As a final note on the comparison with my SLR: There is basically no comparison between the good indoors flash pictures taken with the Fuji and those taken with the SLR: Fuji's are way better! Except that they are only in focus when there is a lot of light and the content is never the instance that I want. The SLR's have bad colors and exposure, proving a crappy flash, but they are always in focus and contained what I wanted in the first place....

I will probably tell you my hands-on exerience with the 7i tomorrow... we'll see... I am so sorry for this, the quality of the image is so nice. But what is the use when the subject is never what you want it...
 
According to the specifications page for the Canon Rebell 2000 on
the Canon website, the 2000 does have an AF assist beam, as
quoted from the page:
Now that makes sense to me, but I don't think that Stefan believes
it. I suppose it's possible to use the flash if the focus method
was to use the flash to somehow measure the camera to subject
distance and then set the focus before firing the main flash. The
double flash, though, is more likely a preflash to set the
exposure, just like digital. If, on the other hand, the flash is
the focus assist, I'd like to know how an ordinary electonic falsh
can maintain a light output long enough to set the focus. Flashes
work by discharging a capicator though the gas in the flash lamp.
This discarge takes only a very short time. So I can't imagine how
it could remain on long enough to focus the camera let alone have
enough energy left to expose the image. In any case, since digital
cameras work by adjusting for maximum contrast, only a steady focus
assist lamp would be of any use.

Dewdrop
You are right, I can't really believe it... I am pretty handy with
devices in general, I would say, and I've bee looking very
thorughly at the camera. There is nothing else than the flash (or
the red eye reduction little led, that I checked not to be
responsible) that could emmit any kind of light. Also, the camera
has a night portret mode, in which it uses the built in flas as a
lantern (it stays on, although obviously not at full strength, for
several good seconds). So they must have overcome the fast flash
problem somehow (probably an additional basic light bulb). However,
what it is doing is indeed when focusing is indeed flashes not a
continous light.

Anyway, I decided to take the matter into my own hands, and after
the guys at Ritz camera assured me that the camera is returnable
for a full refund within 10 days, I bought a Fuji 602z today. The
first thing I wanted to check was obviously the low light focus,
what it is trying and what is it managing to do. The focus is
almost nonexistant! It really needs A LOT of light to focus. and it
would not use the flash, even though I actually tried to make it do
so (I am talking about focusing, it does use flash for the
picture). Also, the applauded-by-some "super-fast" good light focus
is not that fast at all. There is a lot of lag somewhere along the
way even with prefocus. I could not get one single picture the I
wanted, it always came up something else, since there was no way to
tell when the picture will actually be taken. I know that it is the
advantage of digital that you can just check the picture, delete it
and take another one. But it was just too much russian rouletting
fo me. It would also not use the flas in supermacro mode (I guess
it would be useless thanks to the huge lens barrel). On a purely
personal oppinion: I find the grip huge, not necesarily
unconfortable, but too big, as well as the camera overall. What can
I say, than that I am really really disappointed by the camera. It
is going right back first thing tomorrow morning!

As a final note on the comparison with my SLR: There is basically
no comparison between the good indoors flash pictures taken with
the Fuji and those taken with the SLR: Fuji's are way better!
Except that they are only in focus when there is a lot of light and
the content is never the instance that I want. The SLR's have bad
colors and exposure, proving a crappy flash, but they are always in
focus and contained what I wanted in the first place....

I will probably tell you my hands-on exerience with the 7i
tomorrow... we'll see... I am so sorry for this, the quality of the
image is so nice. But what is the use when the subject is never
what you want it...
The 7i is a good camera......as digital cameras go. If you are expecting it to do as well as your SLR in low-light focussing, particularly in action shots, forget it.

To me the other benefits of the digital system outweigh these hassles, but different folks are different.
Best regards,
--
DaveMart
 
I will probably tell you my hands-on exerience with the 7i
tomorrow... we'll see... I am so sorry for this, the quality of the
image is so nice. But what is the use when the subject is never
what you want it...
Stefan,

The 7i has excellent low light focus with some special considerations. I own a 7i and have been able to get focus in light so dim I had trouble seeing objects with my naked eye. However, it isn't fast. The dimmer the light, the slower the focus and it may take several tries. The EVF switches to black and white in dim light and boosts the gain which allows you to frame the subject in pretty dim conditions. As to focusing, remember that the focusing system adjusts for optimum contrast on a vertical line or edge. So you should set the camera for spot or flex focus and point the camera or move the focus point so that a vertical edge of reasonable contrast is at the focus point. Then press the shutter button half way, recompose if necessary, and take the shot. Be sure that you hold the camera as still as possible while it is trying to focus. It can't judge best contrast when the edge is moving. Also, the motion can cause objects to blur in such a way as to appear like good contrast and you'll get a false focus lock indication. You need to practice to avoid this.

Another thing you will notice in dim light with a B&W EVF mode is that the image in the viewfinder will smear or blur if you move the camera or the suject is moving. This is annoying, but I've gotten used to it and manage to get decent shots. Hopefully, you won't be shooting in light that dim.

If working with the 7i doesn't do it for you, I doubt that you will find a digital camera for your purposes unless you are willing to spend really big bucks (at least $5000, maybe more) for a professional camera.

Let us know how you make out.

Dewdrop
 
Thanks a lot for sharing this with me. I returned the 602 today. They weren't extremely happy but they didn't say anything or give me any hassle. Thumbs up for that (thumbs down for the price, though).

AS a reply to David as well, I understood by now that only a 2000$ dSLR will ever get close to a 200$ SLR (I am talking about bodies) in terms of shot and focus responsivness. I am wondering why. I am not a physics and technology illterate (actually, I am currently doing physics and electrical engineering at one of the best universities in the US). Still, unless the actual film strip has something to do with the focus (which is common sense obviously not true, and cam be straight forward proven by focusing and shoting without film in the camera) I don't see what the diference between digital and film metering and focusing is. I don't know exactly what a film camera is using to focus, but I can't see why a digital one can't use the same thing. I mean it's just lenses, is it? It can't be the focal length either. The wide angle from film intersects with the telephoto from digital in actual focal lengths, for a decent range. Yet digital is still far behind, when comparing performance at the same focal length. Whatever is there in a film camera, why can't they put it in a digital one, and just replace the film by a CCD?

Sure enough, though, I am only curious to see an explanation. I realise that this is just what it is, take it or leave it. And knowing what it is, I decided to try it. Still the 602 disappointed me. As you were saying, I realise that low light focus will take more. It does on the SLR anyway. Had the 602 had a slow low light focus, it would have been OK, but it doesn't have one at all! On top of that, what I found particularly annoying was the shot lag, given it was prefocused. I prefocused, waited for the shot, took it and got something different. I can't really measure by hand such short intervals, but I am pretty sure it could not have been a 0.1 seconds average as the reviews say. And this lag should not depend on the quantity of light, should it (I mean, it's only applying what it already has)?

I see a bunch of sample action photos floating around, taken with various cameras. Is it that they just happen to fall at the right moment, aided by the photographer's anticipation, still one out of 100 tries? Or should I hope that I stumbled around a particularly crappy unit, and that action photgraphy is not impossible?

Right now I am waiting or an Olympus C-730 in a store nearby, I am going to give that a shot as well. For the time being I am kind of scared of the Minolta. I wanted lots of features but upon handling the fuji I realized I may end up just taking a point-and-shoot picture most of the time, so....

I'll let you all know what comes out of this.

Do you think I should start a new thread on the differences between the actual picture taking (and focus, maybe) speed between film and digital, and why is digital so much slower? I am really interesetd in the issue... Was there such a talk, that you know of, before?

PS: I did try all your suggestions before deciding the fuji is virtually unusable in low light... Not too much improvenment there...
I will probably tell you my hands-on exerience with the 7i
tomorrow... we'll see... I am so sorry for this, the quality of the
image is so nice. But what is the use when the subject is never
what you want it...
Stefan,

The 7i has excellent low light focus with some special
considerations. I own a 7i and have been able to get focus in
light so dim I had trouble seeing objects with my naked eye.
However, it isn't fast. The dimmer the light, the slower the focus
and it may take several tries. The EVF switches to black and white
in dim light and boosts the gain which allows you to frame the
subject in pretty dim conditions. As to focusing, remember that
the focusing system adjusts for optimum contrast on a vertical line
or edge. So you should set the camera for spot or flex focus and
point the camera or move the focus point so that a vertical edge of
reasonable contrast is at the focus point. Then press the shutter
button half way, recompose if necessary, and take the shot. Be sure
that you hold the camera as still as possible while it is trying to
focus. It can't judge best contrast when the edge is moving.
Also, the motion can cause objects to blur in such a way as to
appear like good contrast and you'll get a false focus lock
indication. You need to practice to avoid this.

Another thing you will notice in dim light with a B&W EVF mode is
that the image in the viewfinder will smear or blur if you move the
camera or the suject is moving. This is annoying, but I've gotten
used to it and manage to get decent shots. Hopefully, you won't be
shooting in light that dim.

If working with the 7i doesn't do it for you, I doubt that you will
find a digital camera for your purposes unless you are willing to
spend really big bucks (at least $5000, maybe more) for a
professional camera.

Let us know how you make out.

Dewdrop
 
I just foun this on the web, in a review of Rebel 2000 ( http://www.photo.net/canon/eos-300 )

In low light, the flash is used to provide autofocus assist light, which is accomplished by firing flash bursts. Do that a few times to people, and they might start developing agressive behavior toward your person. The good side is that you can run away while they are totally blinded by the flash bursts, and the angry expressions on your subjects faces will be extremely realistic (but they might not be looking directly at you, since they can't see you anymore). If you are in the "creative" modes, the camera will only do this if the flash is already popped up (so you could wait until the focus is done to pop up the flash), but in the idiot modes, the camera will pop up the flash as needed.

So it does use flash burst for auto focus...
"AF-assist Beam: Automatically emitted when necessary and aimed at
the area covered by the active focus point."

This would not be the flash. Surely this is covered in your owner's
manual.

The principle is exactly the same with digital cameras. The ones
with AF assist lamp focus well in the dark, the ones without don't.
The Olympus C-2100UZ example was spot on because its AF assist lamp
allows it to snap into focus rather quickly in the dark.

Rick
Low light focus problems do apply to flash photos. The preflash is
used to set exposure, not focus. If the camera can't focus, you'll
get a well exposed blur.
Then this is a HUGE difference between SLR and digital! I just
tested my SLR to make sure: In a very dark room it fired the flash
and perfectly focused in less than a second. It does use flash for
foscusing and I am very surprised that digitals cameras don't why
would that be?
Are you sure?

Thanks,

Stefan
 
Thanks a lot for sharing this with me. I returned the 602 today.
They weren't extremely happy but they didn't say anything or give
me any hassle. Thumbs up for that (thumbs down for the price,
though).
AS a reply to David as well, I understood by now that only a 2000$
dSLR will ever get close to a 200$ SLR (I am talking about bodies)
in terms of shot and focus responsivness. I am wondering why. I am
not a physics and technology illterate (actually, I am currently
doing physics and electrical engineering at one of the best
universities in the US). Still, unless the actual film strip has
something to do with the focus (which is common sense obviously not
true, and cam be straight forward proven by focusing and shoting
without film in the camera) I don't see what the diference between
digital and film metering and focusing is. I don't know exactly
what a film camera is using to focus, but I can't see why a digital
one can't use the same thing. I mean it's just lenses, is it? It
can't be the focal length either. The wide angle from film
intersects with the telephoto from digital in actual focal lengths,
for a decent range. Yet digital is still far behind, when comparing
performance at the same focal length. Whatever is there in a film
camera, why can't they put it in a digital one, and just replace
the film by a CCD?
Sure enough, though, I am only curious to see an explanation. I
realise that this is just what it is, take it or leave it. And
knowing what it is, I decided to try it. Still the 602 disappointed
me. As you were saying, I realise that low light focus will take
more. It does on the SLR anyway. Had the 602 had a slow low light
focus, it would have been OK, but it doesn't have one at all! On
top of that, what I found particularly annoying was the shot lag,
given it was prefocused. I prefocused, waited for the shot, took it
and got something different. I can't really measure by hand such
short intervals, but I am pretty sure it could not have been a 0.1
seconds average as the reviews say. And this lag should not depend
on the quantity of light, should it (I mean, it's only applying
what it already has)?
I see a bunch of sample action photos floating around, taken with
various cameras. Is it that they just happen to fall at the right
moment, aided by the photographer's anticipation, still one out of
100 tries? Or should I hope that I stumbled around a particularly
crappy unit, and that action photgraphy is not impossible?
Right now I am waiting or an Olympus C-730 in a store nearby, I am
going to give that a shot as well. For the time being I am kind of
scared of the Minolta. I wanted lots of features but upon handling
the fuji I realized I may end up just taking a point-and-shoot
picture most of the time, so....

I'll let you all know what comes out of this.

Do you think I should start a new thread on the differences between
the actual picture taking (and focus, maybe) speed between film and
digital, and why is digital so much slower? I am really interesetd
in the issue... Was there such a talk, that you know of, before?

PS: I did try all your suggestions before deciding the fuji is
virtually unusable in low light... Not too much improvenment
there...
Don't know the technicalities of focussing myself, but SLR's and other cameras use entirely different focussing systems. The light coming in to the camera allows the SLR to determine the correct range and homein directly to focus.

On most digitals this system is not usable, and the camera has to, say, increase the focal length until it has gone to far and come back to the correct distance after it realised it has gone too far.
From what you are saying the Sony 717 may be your best bet.

It has excellent low-light focus, now that they are fixing the bugs, providing that:
The subject is not too far away
It's not too small.
It's not an animal that can be frightened by the holographic illumination.
It's not going to upset people.

You may not find it quite so daunting as the D7i.
It's got to be between these two cameras.

Don't forget that 95% of your photography will probably be in lighting conditions which are fine, and if you save up and buy something like the 3600HS(D) flash, it really is a great flash and will make the conditions under which you cannot get a decent picture rare indeed.

Just count yourself lucky that you don't have to mix and explode chemicals for your flash!
Best regards,

--
DaveMart
 

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