F11 flash

[MissScarlett]

Does the camera adjust the power of the flash? Someone said on another thread that it does NOT, but it seems to. One of the main reasons I returned the Z1 and bought F11 (besides picture quality) was that the F11 flash supposedly has a range of over 20 feet, compared to 9.8 feet for the Z1. However, when I tried the F11 from about 8-10 feet away (to get a person full-length) in a dim room, it's underexposed. That was auto, 800iso, 1/60.

I experimented trying to get a brighter picture by using flash in S mode, slower and slower (iso set at 800). With the aperture remaining at 2.8, shouldn't the pictures get brighter and brighter as the shutter got slower? But they got progressively DARKER (until I went so slow that they brightened up from the ambient light, but the flash hardly showed at all). So it seems that the camera does lower the flash power, or is there something else obvious that I'm missing? In a dim room are the only choices 1) to take a bright but shaky flashless picture at around 1/4 second or 2) an underexposed flash picture at 1/60? Isn't there any way to trick it into doing a full-strength flash at a slightly slower speed? I haven't finished reading the entire manual yet; EV adjustments disabled with flash (as with the Z1)?

Of course we all buy F10/11s mainly to take natural light pictures, but for those of us who can only have ONE new camera at the moment, there will be times when flash is needed. W3 mentioned in another thread that he thought Z1 and F11 had the same flash, but when I looked at the specs they said 9.8 feet vs. over 20ft-- did they mean 20 ft only at 1600iso? I don't know enough PP yet to use 1600 often, esp. not for flash.

 

[Poochdp]

I cant answer your queston about the dimming of the exposur as you slowed the shutter speed. I think it would help if you post a few pics with the exif info for better help.

The one thing I have noticed with my F11 flash is that it is angeled to center on a point I would say about 10 feet out, when I have used it as fill beyond that, I notice that I get bright on the lower half and even in on the ground in front of the subject and it gets darker as you go up. Anwywhere under 8-10' or less, seems to hit is mark fairly well.

I dont know if the power varies, I doubt it though, if it did, I think they would have given us a fill flash menu item.

 

[Kim Letkeman]

I think the power reduces in macro ...

 

[MissScarlett]

I cant answer your queston about the dimming of the exposur as you
slowed the shutter speed. I think it would help if you post a few
pics with the exif info for better help.

Thanks, I'll do that after experimenting in a more controlled setting-- maybe with a tripod to make sure the difference isn't from my holding it differently. When I repeated a few more hand-held shots just now, I had mixed results on the decreasing speeds, but 1/60 S mode seemed consistently darker than 1/60 auto (both at 800iso, f2.8). Maybe S mode does something different (like with Macro as Kim said below).

I notice that I get bright on the
lower half and even in on the ground in front of the subject and it
gets darker as you go up.

Does that mean that at over 10 feet (on vertical pictures) it would help to have your left (the subject's right) side to a wall to bounce off the light? Or holding it upside-down horizontally so it hits the faces instead of the feet?

Come to think of it, on another thread where someone posted some flash pictures of 3 girls in prom dresses, the left side of the picture (about 12 ft away) was much better lit than the right! Must have been a vertical shot-- I'll try to search for it again.

 

[w3]

I think the power reduces in macro ...

I thought F10's Flash would throttle down in Macro too until recently.

As a result of one of my boring discussions, I went to check out some numbers about various Flash modes. And I found out something about F10's Macro that I wasn't quite aware of before.

Here is what I think F10's Flash (likely the same with F11) does in Macro.

It doesn't reduce the Flash Power in Macro. The Flash Power will remain constant.

Using Macro mode with Flash and Auto ISO, I will end up with shots at the lower ISO zone, mostly between ISO 80 and 200 (400), while regular Auto Flash works between ISO 200 and ISO 800 with Auto ISO.

IN ADDITION, IT WILL NARROW THE APERTURE IN ORDER TO GET LESS LIGHT IN MACRO FLASH MODE!

In other words, it uses lower ISO and narrower Aperture to reduce the Flash effect (while the Flash power remains constant) under Auto Macro Flash.

I will have Macro Flash Shots at lower ISO and narrower Aperture than F2.8 (like F4).

No wonder I don't have problems with F10's Macro Flash Shots. They look really good to me most of the time.

 

[w3]

Does the camera adjust the power of the flash? Someone said on
another thread that it does NOT, but it seems to. One of the main
reasons I returned the Z1 and bought F11 (besides picture quality)
was that the F11 flash supposedly has a range of over 20 feet,
compared to 9.8 feet for the Z1. However, when I tried the F11
from about 8-10 feet away (to get a person full-length) in a dim
room, it's underexposed. That was auto, 800iso, 1/60.

I experimented trying to get a brighter picture by using flash in S
mode, slower and slower (iso set at 800). With the aperture
remaining at 2.8, shouldn't the pictures get brighter and brighter
as the shutter got slower? But they got progressively DARKER

Sorry for the late response.

I finally had a chance to do a little experiment trying to duplicate what you did.

I did it under 3 different ambient light levels - what I would call High, Medium and Low ambient light, but they are ALL STILL LOW LIGHT CONDITIONS. The incandescent lighting in my dinner room has a dimmer switch.

I couldn't duplicate your observations of getting Darker as you went Slower under all 3 different ambient light levels.

I started with 1/60s and slowed the shutter speed down to 1/20s at each of the three ambient light levels.

The results I got were as expected. When there was High ambient light, the help was obvious. When there was Medium ambient light, you could still see the minor improvement. When the ambient light was low, there was not much difference. While it didn't make the picture any brighter (nor darker), however, I did notice at Low ambient light level as I slowed the shutter speed down to 1/20 that the weak incandescent light did manage to slip into the picture to change the white balance a little bit.

(until I went so slow that they brightened up from the ambient
light, but the flash hardly showed at all). So it seems that the
camera does lower the flash power, or is there something else
obvious that I'm missing?

I know you could be thinking, and not illogically, that the F11 might cut down its Flash power to match the slowed down shutter speed and sometimes might overdo it. But I couldn't verify that.

In addition, if that were the case, increasing the shutter speed (say to 1/500s or 1/1000s) would then help the F11 to unleash the full flash power? Unfortunately, it doesn't do that. It was already at full power. Just tried another little experiment increasing the shutter speeds too. It didn't help but didn't hurt much either under low ambient light. I think the reason may be that the onboard flash lasts about 1/1000s only (please correct me if I am wrong here), and so I didn't really cut down the flash exposure by going to 1/1000s.

To sum it up: for Shutter Speed to play a role, for slower shutter speed to help with Flash shots, THERE HAS TO BE ENOUGH AMBIENT LIGHT. If the ambient light is very low, it doesn't matter much what shutter speed you use.

In a dim room are the only choices 1) to
take a bright but shaky flashless picture at around 1/4 second or
2) an underexposed flash picture at 1/60? Isn't there any way to
trick it into doing a full-strength flash at a slightly slower
speed? I haven't finished reading the entire manual yet; EV
adjustments disabled with flash (as with the Z1)?

Of course we all buy F10/11s mainly to take natural light pictures,
but for those of us who can only have ONE new camera at the moment,
there will be times when flash is needed. W3 mentioned in another
thread that he thought Z1 and F11 had the same flash,

I probably said that according to dpreview's product summaries, both F10 and F11 have a Flash Guide No of 9.8 feet (Guide No is defined as the effective distance of the flash with the camera at aperture F1 and ISO 100 - translated to about 5 ft at F2.8 ISO 200, or back up to about 10 ft at F2.8 ISO 800)

but when I
looked at the specs they said 9.8 feet vs. over 20ft-- did they
mean 20 ft only at 1600iso? I don't know enough PP yet to use 1600
often, esp. not for flash.

Guide No of 9.8 would get it up to about 14ft at F2.8 ISO 1600.

To get to 20 ft at F2.8 ISO 1600, you have to start with an onboard flash that has a Guide No. of about 14.

(Checking: Guide No = Distance x F Number at ISO 100
Guide No 14 means 14 ft only if at F1 and ISO 100
but it is F2.8, so the distance will be 14/2.8 = 5 ft at ISO 100
from ISO 100 to ISO 800 is 3 stops, to 1600 is 4 stops
5 x 1.4142 x 1.4142 x 1.4142 = 14 ft at ISO 800
x 1.41.2 one more time = 20 ft at ISO 1600 )

 

[Sunshine_boy]

I think you are right W3 about the fixed duration of the flash.

But I think it may not be as 'sharp' as 1/1000 but certainly shorter than 1/125. So, in theory, if you are in total darkness, a slower shutter speed will not give you a brighter picture. I remember seeing (years ago) examples of frozen action (eg breaking an egg) done by special flash guns that had a very short duration (1/1000?) used with the 'B' mode in which the shutter stayed open long before and after the flash fired.

This would explain our friend's description of the F11 behaviour.
--
Sunshine
If you see anybody without a smile on, give him one of yours... )

 

[X2222]

I think the power reduces in macro ...

It definetly does. In order not to overexpose the picture, especially with auto iso, if the range is only a couple feet or closer switch on the macro mode and the flash will expose the pic properly.

The f10/f11 does have a long flash range but thats only when used with high iso settings which ultimately serve to increase the flash range. Using auto iso indoors will do the trick.

 

[w3]

I think the power reduces in macro ...

It definetly does. In order not to overexpose the picture,
especially with auto iso, if the range is only a couple feet or
closer switch on the macro mode and the flash will expose the pic
properly.

In my opinion, it does so probably by not adjusting the actual POWER, but by adjusting the EFFECT via Lower ISO and Narrower Aperture.

Please check your Macro Flash shots' EXIF numbers.

Please see my post above.

The f10/f11 does have a long flash range but thats only when used
with high iso settings which ultimately serve to increase the flash
range. Using auto iso indoors will do the trick.

 

[Kim Letkeman]

I did it under 3 different ambient light levels - what I would call
High, Medium and Low ambient light, but they are ALL STILL LOW
LIGHT CONDITIONS. The incandescent lighting in my dinner room has
a dimmer switch.
...
To sum it up: for Shutter Speed to play a role, for slower shutter
speed to help with Flash shots, THERE HAS TO BE ENOUGH AMBIENT
LIGHT. If the ambient light is very low, it doesn't matter much
what shutter speed you use.

For years now, the use of capitals in a posting or email has been used to indicate shouting, usually in anger. I realize that you are using it for emphasis, but there are other ways to indicate emphasis that do not trigger the immune response many of us have built up over the years.

The easiest way to emphasize a phrase would be to surround it with asterisks. For example:

"... for Shutter Speed to play a role, for slower shutter
speed to help with Flash shots, there has to be enough ambient
light . If the ambient light is very low, it doesn't matter much
what shutter speed you use."

I only suggest this because I can't really enjoy your posts when many paragraphs contain what I automatically process as shouting. I hope that this does not offend you, I'd just like to be able to comfortably follow your discussions.

--
My gallery: http://letkeman.net/Photos

 

[w3]

Hi Kim,

Your suggestion is well taken.

I would have used bold, underline or italic if available, unfortunately they are not.

I will try to reduce the use of the occasional CAPs ... oops

I
hope that this does not offend you, I'd just like to be able to
comfortably follow your discussions.

Not offended.

And sincerely thank you for trying to follow my discussions.