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03-16-2012, 11:19 AM   #121
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QuoteOriginally posted by Clavius Quote
And that's the no1 reason why I don't like Apple products. You've got no freedom. "Not certified? Sorry, you're not even allowed to even try."
Oh yes you do. You have the freedom of not purchasing Apple products and remain in the dark ages.

03-16-2012, 11:21 AM   #122
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QuoteOriginally posted by Quicksand Quote
Lage, you're absolutely 100% correct, of course.

I agree with Qwntm to some extent -- yes, ISO400 and f/4.5 at 4 feet does have the potential to blow out when flash is used, UNLESS the flash power is controlled appropriately. That's why it's a good test.

And when direct flash is used, it works fine. When wireless flash is used, it works fine.

I don't buy the argument about the indirect bounce flash trying to light up the rest of the room. That doesn't make any sense. The way P-TTL is SUPPOSED to work, a preflash gets sent out, and the camera meters the scene twice to figure out how much the preflash affected the actual in-frame scene by calculating the difference between the ambient light exposure and the preflash-lit exposure.

The flash power is then adjusted to bring the predicted exposure up to a well-exposed scene, when factoring in ambient plus flash. P-TTL doesn't care about the rest of the room, only what the lens sees.

And it's failing in this use scenario.
Can anyone post pics with EXIF-info that shows direct flash vs bounce flash @ ISO400, f4.5, 4 feet?

(Or as we used to say; Screenshot, or it didn't happen )
03-16-2012, 01:26 PM   #123
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QuoteOriginally posted by morpho Quote
Can anyone post pics with EXIF-info that shows direct flash vs bounce flash @ ISO400, f4.5, 4 feet?

(Or as we used to say; Screenshot, or it didn't happen )
There's no EXIF in this because it's a composite, but here:



(From this post a couple of months ago.)

I can tell you -- because I took the shots and looked at the exposure info personally -- that all of the shots were as described (ISO400 f/4.5 1/125). It's on my agenda to perform another, more rigorous set of tests, that I can send in with the camera when I get it serviced. I'll post here too.
03-17-2012, 04:32 AM   #124
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Just updated the firmware. The focus motor definitely spins the lens faster.

03-17-2012, 08:49 AM   #125
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QuoteOriginally posted by Quicksand Quote
There's no EXIF in this because it's a composite, but here:



(From this post a couple of months ago.)

I can tell you -- because I took the shots and looked at the exposure info personally -- that all of the shots were as described (ISO400 f/4.5 1/125). It's on my agenda to perform another, more rigorous set of tests, that I can send in with the camera when I get it serviced. I'll post here too.
But does the bounce flash work properly when you are photographing something 10 feet away? Or let's say a person sitting in a chair from 6-8 feet away?

I just don't like the test where you are bouncing on a subject that's the size of a small apple from 4 feet... If everything's working when you shoot a room sized shot bounced and then craps out at 4 feet on a mouse, I'd say you are exceeding the parameters.

The examples you have shown seem very on the edge of the parameters of what's do-able to me, and you might be crossing that line when you bounce. That's all I'm trying to get across.

Take some bounce shots of your dining room table and see what happens...
03-17-2012, 07:50 PM   #126
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QuoteOriginally posted by Qwntm Quote
The examples you have shown seem very on the edge of the parameters of what's do-able to me, and you might be crossing that line when you bounce. That's all I'm trying to get across.
Oh, for heaven's sake.

When I use direct on-camera flash, exposure is correct, time after time after time.

When I use direct off-camera wireless P-TTL flash, exposure is correct, time after time after time.

When I use bounce off-camera wireless P-TTL flash, exposure is correct, time after time after time.

But when I bounce the flash ON-camera, I get overexposure every time.

Do you mind telling me -- what design parameter might I be exceeding when I reattach the flash?

IT'S BROKEN! REALLY!

Not just at four feet, with those examples I showed. That's just an example I happened to post! It happens all the time!

QuoteOriginally posted by Qwntm Quote
But does the bounce flash work properly when you are photographing something 10 feet away?
NO!

QuoteOriginally posted by Qwntm Quote
Or let's say a person sitting in a chair from 6-8 feet away?
NO!

I wouldn't be complaining if that were the case.
03-17-2012, 11:32 PM   #127
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QuoteOriginally posted by kent Quote
Just updated the firmware. The focus motor definitely spins the lens faster.
Think he's onto something here. AF sounds zippier on my 28-80. As if it wasn't scary enough when it reaches the edges and goes *clack*...Don't think this will affect most modern lenses though, as a lot of them are going to be using internal motors.

Other than this, nothing noticeable on my end. Updated around 2 weeks ago.
03-18-2012, 01:36 AM   #128
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There have been some talk for the K5 center point focus, uses a larger area than the red focus dot.
Focusing on objects distend from each other but close to the center (moving red dot minimal from one point to another) the camera reacts precisely within the red dot. Am I making sense here?

Is it just my K5 or is it the1.13 firmware that have "fixed" this?

03-18-2012, 05:33 AM   #129
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QuoteOriginally posted by Pontax Quote
There have been some talk for the K5 center point focus, uses a larger area than the red focus dot.
Focusing on objects distend from each other but close to the center (moving red dot minimal from one point to another) the camera reacts precisely within the red dot. Am I making sense here?

Is it just my K5 or is it the1.13 firmware that have "fixed" this?
Nope, if anything its the other way around.
The red focus conformation square that most people think is actualy the focus area is far larger !
On the k5 I can tell you it its actualy the size of the two
semi circles that mark spot metering in your veiwfinder.
this is why most think they are getting front and back focussing issues. Its genraly because people try focusing on the eye etc, and because the focus point is so large it can latch onto the nose or ear.... hence back or front focus confusion. Since the eye is so close to the side of the head, if full fruntal, its poss the focus can miss altogether and latch onto whatever is behind if it has more contrast etc.
03-18-2012, 08:04 AM   #130
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I just did a quick flash test using 1.13. This may or may not be conclusive, but this is what I did:

I manually set ISO to 100, 400 and 1600 for the tests. Camera on tripod, about 1.5m from subject. Metered with multi-pattern mode. Subject is both light and dark (it's a small plywood box with 3 dark brown beer bottles in it). Some natural daylight coming from 2 windows on each side of the subject, no direct sun though (it's a bit cloudy). AF360FGZ flash used on-camera. P-TTL mode. Camera on P mode. Flash exposure comp on 0.

ISO 100, direct flash (0 degrees): ok (subject a bit bright, but not blown)
ISO 100, bounce flash (45 degrees): ok, nicely lit
ISO 400, direct flash (0 degrees): ok (subject a bit bright, but not blown)
ISO 400, bounce flash (45 degrees): ok, nicely lit
ISO 1600, direct flash (0 degrees): ok (subject a bit bright, but not blown)
ISO 1600, bounce flash (45 degrees): ok, nicely lit

Basically, I am seeing a nicely exposed bounce flash subject. If anything, the direct flash is not very good with this subject, but I believe this is the subject's fault and not the metering or flash. I do question whether the natural light coming in the windows is having a significant effect, or not. I will try the same tests again after it gets dark.
03-18-2012, 08:29 AM   #131
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QuoteOriginally posted by Quicksand Quote
Oh, for heaven's sake.

When I use direct on-camera flash, exposure is correct, time after time after time.

When I use direct off-camera wireless P-TTL flash, exposure is correct, time after time after time.

When I use bounce off-camera wireless P-TTL flash, exposure is correct, time after time after time.

But when I bounce the flash ON-camera, I get overexposure every time.

Do you mind telling me -- what design parameter might I be exceeding when I reattach the flash?

IT'S BROKEN! REALLY!

Not just at four feet, with those examples I showed. That's just an example I happened to post! It happens all the time!



NO!



NO!

I wouldn't be complaining if that were the case.
Well how would I know all that? All you said was 4 feet at f4.5 at iso 400 and then showed samples of a small car on a rug...

The internet is full of people complaining about their camera being broken because when they run a "test" like photographing a light bulb at 5 stops under and then recover the details by pushing the development in photoshop by 8 stops there's some kind of artifacts or something, know what I mean?

From the additional information, it sounds like it's broken... send it in to service.
03-18-2012, 11:58 AM   #132
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QuoteOriginally posted by kent Quote
Just updated the firmware. The focus motor definitely spins the lens faster.
I don't mean to sound condescending, but how can firmware make an electric motor spin faster? Wouldn't increasing the voltage in order to spin the motor faster require a change to the circuitry?
03-18-2012, 12:14 PM   #133
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I'm not saying it IS spinning faster, I haven't noticed it. But it is possible to increase speed via firmware if they are using something more advanced then the absolutely simplest type of DC motor. And even then it is possible if it wasn't running with full speed before.
03-18-2012, 12:56 PM   #134
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These are digitally controlled stepping motors...directly controlled by the CPU. Otherwise the camera would never be able to lock on focus.
03-18-2012, 01:05 PM   #135
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QuoteOriginally posted by cbope Quote
I just did a quick flash test using 1.13. This may or may not be conclusive, but this is what I did:

I manually set ISO to 100, 400 and 1600 for the tests. Camera on tripod, about 1.5m from subject. Metered with multi-pattern mode. Subject is both light and dark (it's a small plywood box with 3 dark brown beer bottles in it). Some natural daylight coming from 2 windows on each side of the subject, no direct sun though (it's a bit cloudy). AF360FGZ flash used on-camera. P-TTL mode. Camera on P mode. Flash exposure comp on 0.

ISO 100, direct flash (0 degrees): ok (subject a bit bright, but not blown)
ISO 100, bounce flash (45 degrees): ok, nicely lit
ISO 400, direct flash (0 degrees): ok (subject a bit bright, but not blown)
ISO 400, bounce flash (45 degrees): ok, nicely lit
ISO 1600, direct flash (0 degrees): ok (subject a bit bright, but not blown)
ISO 1600, bounce flash (45 degrees): ok, nicely lit

Basically, I am seeing a nicely exposed bounce flash subject. If anything, the direct flash is not very good with this subject, but I believe this is the subject's fault and not the metering or flash. I do question whether the natural light coming in the windows is having a significant effect, or not. I will try the same tests again after it gets dark.
As a follow up, I re-ran the same tests after dark with minimal artificial light in the room (a single 7w CFL), and I could just copy/paste the above results.

I am seeing no problem at all with bounce flash exposure using an AF360FGZ and firmware 1.13. Bounce exposures look very natural, while direct is harsh as expected. I can post pics with exif data if someone is interested, but it's getting late here tonight.
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