Flash problem with 7D and AF 28-75mm/2.8

hongsien · 29th August 2005

Hi all,

A friend of mine has a problem with using a Minolta flash 3600 HS on a 7D body in combination with the new AF 28-75mm/2.8 lens. When focused at a subject 1.5m away, and when closing the aperture, the image gets darker and darker........Minolta says the flash needs to be calibrated for the lens combo! Has anyone heard this before?

Hong Sien

TME · 29th August 2005

Yes, I think that's normal without the calibration... just send it back...

But just to clarify, is it the subject only or the background that gets darker and darker? Cos it is the background then that's normal since as u close down the aperture, less ambient light gets into the camera but the subject should remain properly lighted and to the same degree.

Del_CtrlnoAlt · 29th August 2005

err, thats the problem everybody is facing regarding the 7D... the metering goes haywire when the external flash is mounted.

look at the meter, if you use aperture priority mode, without external flash, the shutter will be automatically calibrated to the ev compensation, if external flash is mounted, the meter will stay in centre, then when you stop down, the shutter speed remain the same as the last setting, so you get darker & darker picture... cos background not exposed.

TME · 29th August 2005

Originally Posted by Del_CtrlnoAlt

err, thats the problem everybody is facing regarding the 7D... the metering goes haywire when the external flash is mounted.

look at the meter, if you use aperture priority mode, without external flash, the shutter will be automatically calibrated to the ev compensation, if external flash is mounted, the meter will stay in centre, then when you stop down, the shutter speed remain the same as the last setting, so you get darker & darker picture... cos background not exposed.

Eh? I thought if the camera is on shutter priority with the external flash on, the camera will default to 1/60s, no matter what aperture u use what.... so of course the background just gets darker and darker... that's a feature of all Minolta SLRs right? My Dynax 7 always behaved this way...

hongsien · 29th August 2005

Originally Posted by TME

Yes, I think that's normal without the calibration... just send it back...

But just to clarify, is it the subject only or the background that gets darker and darker? Cos it is the background then that's normal since as u close down the aperture, less ambient light gets into the camera but the subject should remain properly lighted and to the same degree.

I don't think it is 'normal' for a camera to be calibrated for a flash, it should have been designed to work with it properly from the beginning. I never heard this happening with other brands...........

No, she was taking flat objects..........it is not the background that gets darker, the subject is.

Hong Sien

hongsien · 29th August 2005

Originally Posted by TME

Eh? I thought if the camera is on shutter priority with the external flash on, the camera will default to 1/60s, no matter what aperture u use what.... so of course the background just gets darker and darker... that's a feature of all Minolta SLRs right? My Dynax 7 always behaved this way...

Subject is only 1.5 m away! I believe the flash should be strong enough to cover this distance even at F22. Unless she used it at wideangle, but then it should only go dark at the wide setting.........

Hong Sien

Del_CtrlnoAlt · 29th August 2005

Originally Posted by TME

Eh? I thought if the camera is on shutter priority with the external flash on, the camera will default to 1/60s, no matter what aperture u use what.... so of course the background just gets darker and darker... that's a feature of all Minolta SLRs right? My Dynax 7 always behaved this way...

issit? but isn't the metering suppose to work? like when i use Aperture priority, with external flash, it should meter, get the ambience metering or spot, AEL or something, then flash is only to provide illumination of subject.

i think yesterday i tried my 7 for the 1st time, the meter did move in A mode, whereas my 7D meter did not...

Del_CtrlnoAlt · 29th August 2005

hongsien, care to share her shutter speed? cos might be something to do with the High Speed Sync.

hongsien · 29th August 2005

Originally Posted by Del_CtrlnoAlt

hongsien, care to share her shutter speed? cos might be something to do with the High Speed Sync.

Will ask her.........

HS

forbytes · 29th August 2005

ahh, can 3600 be calibrate?

if possible, please post a shot and show us. some of us may be able to help in this wee hours.

TME · 29th August 2005

Originally Posted by hongsien

Subject is only 1.5 m away! I believe the flash should be strong enough to cover this distance even at F22. Unless she used it at wideangle, but then it should only go dark at the wide setting.........

Hong Sien

The flash should cover the subject at 1.5m away but not the background at all... U need to study the shots again (or better post here). Check that it is really the subject that dims... The 3600 has no LCD panel with flash distance displayed so at f/22 I really doubt that the background will be lit.

If it the subject that darkened as u closed down the aperture, then it might be a calibration problem. When I say that it is normal to calibrate for the 3600 and the 5600 flashes, I meant that this is the instruction given by Minolta after they launched the 7D. Cos the flashes were not made with DSLRs in mind then and the way the camera communicates with the flash was probably not completely sorted out before the 7D's launch. Either that was an oversight or some technical thing that could not be overcomed. Anyway the 3600 was not supposed to have this calibration problem, only the 5600.

BTW, DCA, the 5D's had the non-working metering scale back in action unlike our 7D. So the metering should work in manual mode. But I think in aperture priority, the shutter speed is still default at 1/60s.

Hong sien, is that the shutter speed for your friend's shot? I assume that she used aperture priority?

hongsien · 29th August 2005

Hi,

I re-read her email: she used the 5600HS.......my mistake! Don't know the speed she used, still waiting for her reply........I have also send her this thread as a link.....

HS

TME · 29th August 2005

Originally Posted by hongsien

Hi,

I re-read her email: she used the 5600HS.......my mistake! Don't know the speed she used, still waiting for her reply........I have also send her this thread as a link.....

HS

Then it seems likely to be the flash calibration. Cos the 3600 came out after the 5600... I think the 5600 has been around for like 5 years already??? Not sure but i had it since I bought my Dynax 7 in 2002.

hongsien · 30th August 2005

Originally Posted by TME

Then it seems likely to be the flash calibration. Cos the 3600 came out after the 5600... I think the 5600 has been around for like 5 years already??? Not sure but i had it since I bought my Dynax 7 in 2002.

Hi all,

Here are the images, she used shutter speed of 1/60 and the distance to the table is 1.5 meter, so it should be sufficient for the flash to cover even at F22 I think.
below F3.5:

below F5.6:

below F8.0:

below F11:

below F22:

hongsien · 30th August 2005

below F22:

Zerstorer · 30th August 2005

Originally Posted by hongsien

Hi all,

Here are the images, she used shutter speed of 1/60 and the distance to the table is 1.5 meter, so it should be sufficient for the flash to cover even at F22 I think.

Hongsein, the answer might be quite simple. Ask her if she is shooting with bounced flash at 1/60 ISO100.

These shots seem to suggest this and that is the reason why.

hongsien · 30th August 2005

Originally Posted by Zerstorer

Hongsein, the answer might be quite simple. Ask her if she is shooting with bounced flash at 1/60 ISO100.

These shots seem to suggest this and that is the reason why.

Will ask her, but from the shadow, it doesn't seem to be bounched, but who knows.......she used aperture priority (A), so speed is set at 1/60 sec. all the time.......

HS

Drudkh · 30th August 2005

look at the magnifier's shadow, looks bounced.

Don.

TME · 30th August 2005

I thought you were talking about direct flash all the time... Likely to be bounced, the monitor screen shows no reflection at all... quite unlikely if the flash was directed forwards. Also the lighting is very even and not harsh at all... I think we are all quite familiar with the light quality of the 5600 when used direct...

Drudkh · 30th August 2005

I just did a simple test with 28-75 f/2.8 @ 2m distance.
f/16, f/22 & f/32 with ADI, using 5600HS pointing forward. no sign of insufficeint flash or dark photos.

Dark photos only happens with flash is pointing upward the ceiling, bounced using Pre-TTL at same distance, using f/16, f/22 & f/32.

29th August 2005	#1
hongsien Senior Member Join Date: Mar 2002 Location: Hong Kong Posts: 2,904	Flash problem with 7D and AF 28-75mm/2.8 Hi all, A friend of mine has a problem with using a Minolta flash 3600 HS on a 7D body in combination with the new AF 28-75mm/2.8 lens. When focused at a subject 1.5m away, and when closing the aperture, the image gets darker and darker........Minolta says the flash needs to be calibrated for the lens combo! Has anyone heard this before? Hong Sien

29th August 2005	#2
TME Senior Member Join Date: Jan 2002 Location: Clementi Posts: 6,188	Re: Flash problem with 7D and AF 28-75mm/2.8 Yes, I think that's normal without the calibration... just send it back... But just to clarify, is it the subject only or the background that gets darker and darker? Cos it is the background then that's normal since as u close down the aperture, less ambient light gets into the camera but the subject should remain properly lighted and to the same degree. Last edited by TME; 29th August 2005 at 09:21 PM.

29th August 2005	#3
Del_CtrlnoAlt Senior Member Join Date: Feb 2003 Location: Outside the Dry Box. Posts: 16,342	Re: Flash problem with 7D and AF 28-75mm/2.8 err, thats the problem everybody is facing regarding the 7D... the metering goes haywire when the external flash is mounted. look at the meter, if you use aperture priority mode, without external flash, the shutter will be automatically calibrated to the ev compensation, if external flash is mounted, the meter will stay in centre, then when you stop down, the shutter speed remain the same as the last setting, so you get darker & darker picture... cos background not exposed. __________________ Logging Off Permanently. Those who need to contact me will know where to contact me.

29th August 2005	#8
Del_CtrlnoAlt Senior Member Join Date: Feb 2003 Location: Outside the Dry Box. Posts: 16,342	Re: Flash problem with 7D and AF 28-75mm/2.8 hongsien, care to share her shutter speed? cos might be something to do with the High Speed Sync.

29th August 2005	#10
forbytes Member Join Date: Jun 2003 Location: West, Singapore Posts: 887	Re: Flash problem with 7D and AF 28-75mm/2.8 ahh, can 3600 be calibrate? if possible, please post a shot and show us. some of us may be able to help in this wee hours.

30th August 2005	#15
hongsien Senior Member Join Date: Mar 2002 Location: Hong Kong Posts: 2,904	Re: Flash problem with 7D and AF 28-75mm/2.8 below F22:

30th August 2005	#18
Drudkh Senior Member Join Date: Mar 2004 Posts: 6,019	Re: Flash problem with 7D and AF 28-75mm/2.8 look at the magnifier's shadow, looks bounced. Don.