shutter speed of D7i in studio photography

[hwwong]

I am taking a course about studio photography. According to the tutor, I set the apperture in manual mode to the reading that the light meter recorded for the main light. When I set the shutter speed to around 125 or 250, the pictures turned out extremely overexposed. Then I tried to set it to higher speed like 1500, the pictures looked better.

I was told that this is because of the high sync speed for D7i is high so that a higher speed is needed in studio photography. I am still very confused. Could someone be so kind to explain it to me? Many thanks.

Henry

 

[Barrie Davis]

I am taking a course about studio photography. According to the
tutor, I set the apperture in manual mode to the reading that the
light meter recorded for the main light. When I set the shutter
speed to around 125 or 250, the pictures turned out extremely
overexposed. Then I tried to set it to higher speed like 1500, the
pictures looked better.

I was told that this is because of the high sync speed for D7i is
high so that a higher speed is needed in studio photography. I am
still very confused. Could someone be so kind to explain it to me?
Many thanks.

Henry

--
Hi Henry,

Here are a few questions that may help us to help you:-

1) Evidently you are shooting with flash. If so, are you using a meter suitable for flash?

2) Have you changed the camera to Full Manual Mode, so that the camera isn't setting itself to something you don't want ! ?

3) Have you set the monitor/viewfinder to 'constant brightness' mode?

Generally speaking, with flash as the sole source of light, only the aperture needs to be set, and it should be set to the indicated reading from a flash meter. Once that has been done the D7i shutter can be any speed between 1/60 and 1/250: and the results will look very similar.

However, some studio flash is so powerful even at minimum power it can deliver too much light for the smallest aperture of the D7i, which is f/8.

So, let's see if we can get the flash matching the aperture, and then go on from there.

Please get back to the forum with this extra info.

Regards,
Baz

 

[hwwong]

Thank you for your reply. Here are the answers for your questions:

1)I am using a meter suitable for flash.
2)Yes, I changed to Full Manual Mode.
3)I haven't heard of this "constant brightness". Can you explain this to me?

Generally speaking, with flash as the sole source of light, only
the aperture needs to be set, and it should be set to the indicated
reading from a flash meter. Once that has been done the D7i shutter
can be any speed between 1/60 and 1/250: and the results will look
very similar.

This is exactly what the tutor told us and what I actually did. But the pictures just turned out too bright.

However, some studio flash is so powerful even at minimum power it
can deliver too much light for the smallest aperture of the D7i,
which is f/8.

Then, what should I do if it happens? And how do I know if the power is too much? Does the film camera suffer the problem?

Henry

 

[Chuck Gardner]

When shooting in M mode with flash the shutter speed will not affect the flash exposure, but it will affect the role the ambient studio room lights (if any) have on the exposure. But this should only be a factor if the room lights are very bright.

Most studio strobes, and even cheap on-camera ones like the Vivitar 285HV, have multiple power levels so you might try shooting at 1/4 or 1/16 power.

Also, since light intensity decreases with the square of the distance, if you can double the strobe-to-subject distance the exposure will decrease by 2-stops

Chuck Gardner

I am taking a course about studio photography. According to the
tutor, I set the apperture in manual mode to the reading that the
light meter recorded for the main light. When I set the shutter
speed to around 125 or 250, the pictures turned out extremely
overexposed. Then I tried to set it to higher speed like 1500, the
pictures looked better.

I was told that this is because of the high sync speed for D7i is
high so that a higher speed is needed in studio photography. I am
still very confused. Could someone be so kind to explain it to me?
Many thanks.

Henry

 

[Barrie Davis]

1)I am using a meter suitable for flash.
2)Yes, I changed to Full Manual Mode.
3)I haven't heard of this "constant brightness". Can you explain
this to me?

Generally speaking, with flash as the sole source of light, only
the aperture needs to be set, and it should be set to the indicated
reading from a flash meter. Once that has been done the D7i shutter
can be any speed between 1/60 and 1/250: and the results will look
very similar.

This is exactly what the tutor told us and what I actually did. But
the pictures just turned out too bright.

However, some studio flash is so powerful even at minimum power it
can deliver too much light for the smallest aperture of the D7i,
which is f/8.

Then, what should I do if it happens? And how do I know if the
power is too much? Does the film camera suffer the problem?

Henry

--
Thanks Henry,

OK. On to next stage.

Viewfinder "Constant Brightness" mode:-

When D7 is in MANUAL Exposure Mode the viewfinder/monitor varies in brightness dependant on the actual shutter speed/aperture combination the camera is set to.

This means that when the camera is used indoors with studio flash, and the viewing light is ONLY the modelling lights of the flash, AND the shutter/aperture is set to correct exposure for flash, the viewfinder is TOO DARK to use.

To overcome this problem Minolta added a feature to the 7i & Hi that switches viewfinder to an 'Auto Gain' mode that brightens the viewing image up to normal. This is pretty much essential, if the viewfinder is to be any use at all with studio flash.

To set viewfinder to "Constant Brightness" mode do following:-

a) On 'Command Wheel' Control set PASM to 'M' for Manual. ('M' appears bottom left of viewfinder.)

b) Whilst pressing Command Wheel button (as above) press viewfinder button " i+ " (viewfinder 'M' turns red)

c) Pressing these two buttons together again cancels. ('M' turns back to white.)

This feature IS listed in the manual -- so for verification check there.

If you have NOT NOTICED this viewfinder brightness problem it does suggest that somehow the camera is not set up correctly for manual exposure with studio flash. Lets check some other things that might be wrong........

1) Have you set camera and flashmeter to same ISO? (100 ISO recommended) Set camera ISO manually to 100. Do NOT use "Auto ISO".
Also ensure WB on 'Daylight'.

2) When flashmeter is used does flash fire OK? If so, what actual aperture does meter recommend? Anything higher than f/8 (like f/11 or f/16) is more light than camera can cope with. If that happens, turn down flash power and try again. If neccessary move lights further away. Remember -- white dome must point towards camera!

3) Are you transferring the reading from the meter to the camera without error? Double check!

Please take note. Anything over f/8 is TOO MUCH and will give pictures which are too light, and that is your problem. So please let us know the ACTUAL reading you are getting. This is most important!

I am sorry to take this stage-by-stage approach, but, instead of suggesting lots of things that might be wrong, and possibly confusing you, I hope this way to go directly to what IS wrong. I think it may be quicker in the end.

Regards,
Baz

 

[hwwong]

Thank you for your detailed explanation. The "constant brigntness" mode sounds useful in studio photography. I set the WB to Auto last time and pictures came out too yellow/warm. I will remember these two points next time. Thanks again.

1) Have you set camera and flashmeter to same ISO? (100 ISO
recommended) Set camera ISO manually to 100. Do NOT use "Auto ISO".
Also ensure WB on 'Daylight'.

Yes, I set the camera ISO to 100.

2) When flashmeter is used does flash fire OK? If so, what actual
aperture does meter recommend? Anything higher than f/8 (like f/11
or f/16) is more light than camera can cope with. If that happens,
turn down flash power and try again. If neccessary move lights
further away. Remember -- white dome must point towards camera!

Actually, I didn't have the control of what fstop can be. The tutor did the set up and told us to set the apperture to a certain value. Most of the time, the apperture the meter recorded is around f8 and f11. However, the smallest apperture of D7i is only f9.5 (tele). Therefore, it was sometimes 1/2 stop over. But the overexposed pictures are not just 1/2stop over but looked like 1 to 2 stop over.

Do you think it is the ambient light that caused the overexposure, as suggested by chuck?

Henry

 

[Barrie Davis]

1) Have you set camera and flashmeter to same ISO? (100 ISO
recommended) Set camera ISO manually to 100. Do NOT use "Auto ISO".
Also ensure WB on 'Daylight'.

Yes, I set the camera ISO to 100.

2) When flashmeter is used does flash fire OK? If so, what actual
aperture does meter recommend? Anything higher than f/8 (like f/11
or f/16) is more light than camera can cope with. If that happens,
turn down flash power and try again. If neccessary move lights
further away. Remember -- white dome must point towards camera!

Actually, I didn't have the control of what fstop can be. The tutor
did the set up and told us to set the apperture to a certain value.
Most of the time, the apperture the meter recorded is around f8 and
f11. However, the smallest apperture of D7i is only f9.5 (tele).
Therefore, it was sometimes 1/2 stop over. But the overexposed
pictures are not just 1/2stop over but looked like 1 to 2 stop over.

Do you think it is the ambient light that caused the overexposure,
as suggested by chuck?

Henry

--

The ambient light would have to be as bright as daylight to register at 1/250 sec shutter speed, so I don't think it likely.

Also, if the subject is a light one (lots of white or light tones) 1/2 stop over might look like rather more with digital. Hmmmm......

However, it does look increasingly likely that you are doing NOTHING wrong at all. Indeed, we must not assume that lack of knowledge is the problem. Just because you are new to studio photography with flash does not make you immune to problems with a faulty camera, and that may be what is happening here.

I don't want to give up on this, Henry, but it may be sensible to consult your course tutor. With your camera in his hands he may be able to discover the problem in a minute or two.

But, for the moment at least, I'm stuck !! and I admit it!

If I get any brilliant ideas I will post again. Likewise, if you find out what is going wrong, please keep me/us informed.

I am sorry that you have a problem -- and I'm sorry that I haven't, as yet, been able to fix it.

Regards and Good Luck,
Baz

 

[Bramante M Perkasa]

I assume by using the inbuilt flash, ie poping up the flash.

In ADI or TTL mode this means the flash will try to give the correct output to correctly expose your subject given the current lighting condition, f stop and maybe even distance. This means that closing the aperture down will not give different result. Quite often I am surprised that when using TTL flash I do not get different exposure result on my subject even when I use different aperture, until I realised that the camera will adjust its flash output to compensate for your aperture setting. This MAY throw the calculation away when using studio lights (I have never ever use studio lights in my whole life).

Try:

1. Covering/bouncing your flash with a business card or something so the flash will not reach your subject (not most of it anyway) but will trigger the studio lights.
AND/OR

2. Change the Flash Mode to Manual(?) and change the output to its lowest number (1/8? 1/16? Cannot remember)

and please let us know if it works.

Good luck.

Bram

 

[Chuck Gardner]

The crux of the problem is that the teacher is dictating f/11, a f/stop higher than your camera has. The only practical solution is to get neutral density filter. Each .30 of density in the filter will cut the light by one-stop. A .90 / three-stop filter will give you plenty of exposure headroom. This ND will also be useful for taking blurred motion photos of waterfalls, etc.

Chuck Gardner

I am taking a course about studio photography. According to the
tutor, I set the apperture in manual mode to the reading that the
light meter recorded for the main light. When I set the shutter
speed to around 125 or 250, the pictures turned out extremely
overexposed. Then I tried to set it to higher speed like 1500, the
pictures looked better.

I was told that this is because of the high sync speed for D7i is
high so that a higher speed is needed in studio photography. I am
still very confused. Could someone be so kind to explain it to me?
Many thanks.

Henry

 

[Barrie Davis]

I assume by using the inbuilt flash, ie poping up the flash.

In ADI or TTL mode this means the flash will try to give the
correct output to correctly expose your subject given the current
lighting condition, f stop and maybe even distance. This means
that closing the aperture down will not give different result.
Quite often I am surprised that when using TTL flash I do not get
different exposure result on my subject even when I use different
aperture, until I realised that the camera will adjust its flash
output to compensate for your aperture setting. This MAY throw the
calculation away when using studio lights (I have never ever use
studio lights in my whole life).

Try:
1. Covering/bouncing your flash with a business card or something
so the flash will not reach your subject (not most of it anyway)
but will trigger the studio lights.
AND/OR
2. Change the Flash Mode to Manual(?) and change the output to its
lowest number (1/8? 1/16? Cannot remember)

and please let us know if it works.

Good luck.

Bram

--

Bram -- I see where you are coming from. Trouble is ADI and TTL both produce a double flash, leastways, they do on my D7ug. Studio lights would be triggered on the first flash, wouldn't they?

Henry -- are you able to view the shots you took? If you triggered with your built in flash instead of a hard wired synch lead, do your pictures look as if the studio lights exposed them, or do they look like the built-in flash did the job?
--------------
Have also just noticed on my own camera something I didn't know 2 minutes ago!

When pop-up flash is 'up' in Manual mode, the Auto Gain/Constant Brightness feature (see earlier posting) is re-enabled WITHOUT having to switch it in manually. Yup! Didn't know that! (Fair enough, Minolta. That would be so that there is a usable viewfinder image with built-in flash, whilst the manual switching option extends the same facilty to NON built-in flash, be that studio lights or separate gun. Very Clever.)
--------------

Chuck -- Your suggestion of an ND filter is a sensible workaround, and the value suggested is equally sensible. But I really want to know what's actually happening to Henry. I hate a mystery! and half a stop or so shouldn't make his pictures THAT light, should it?

As you can see, Henry, we are still 'knawing' at it. Let's hope we get there in the end.

Baz

 

[Henry Alexander]

I use my D7 to shoot in the studio all the time.
I use an old set of very powerful Novatron lights.
I also use all the things that have been mentioned
plus I set my on camera flash to 1/16 so it will triger my light
but not effect the exposure.
Finnally, with all that, I use a Minolta Flash meter.
From the first time I starting doing this I have noticed
that it seems to overexpose 1 stop at least.
Because of this, I always shoot one stop less that the meter says.
Why? I am as confused as the rest of you about it, but it happens.
Why I like to use the digital in the studio is that you don't have
to just depend on the meter reading.
You can take a test shot, and see. Ain't digital great!!!!!
Two other notes.
The same thing happens when I use my Vivitar, non TTL flash.

Occasionally I have tried to print the overexposed pictures and they are really not as bad as they seem in the cameras viewer, but I tend to underexpose anyway as I find the highlights tend to "blow out" in digital photographs.

IMHO
HankAlexander

However, it does look increasingly likely that you are doing
NOTHING wrong at all. Indeed, we must not assume that lack of
knowledge is the problem. Just because you are new to studio
photography with flash does not make you immune to problems with a
faulty camera, and that may be what is happening here.

I don't want to give up on this, Henry, but it may be sensible to
consult your course tutor. With your camera in his hands he may be
able to discover the problem in a minute or two.

But, for the moment at least, I'm stuck !! and I admit it!

If I get any brilliant ideas I will post again. Likewise, if you
find out what is going wrong, please keep me/us informed.

I am sorry that you have a problem -- and I'm sorry that I haven't,
as yet, been able to fix it.

Regards and Good Luck,
Baz

 

[Bramante M Perkasa]

Thanks for your response Barrie, by the way I use 7Hi and 7i (there are four in my house at the moment, http://forums.dpreview.com/forums/read.asp?forum=1024&message=5638114 ). Correct me if I am wrong, but I thought only preflash mode (not ADI) emits preflash, at least with the 7i and 7Hi?

Regards,
Bram

 

[Barrie Davis]

Thanks for your response Barrie, by the way I use 7Hi and 7i (there
are four in my house at the moment,

http://forums.dpreview.com/forums/read.asp?forum=1024&message=5638114 ). Correct me if I am wrong, but I thought only preflash mode (not ADI) emits preflash, at least with the 7i and 7Hi?

Regards,
Bram

--
Hi Bram,

Well .... MY D7ug emits TWO flashes on ADI. (just checked) Always has done so too, as I remember.

Of course, I have no way of knowing whether that's right or not. It might be faulty --- might ALWAYS have been faulty. Hmmmm. Thanks ????

(As it happens, I rarely use the built in flash -- mostly for a tiny 'dab' of fill.)

Anyone here able to clarify how many flashes a D7 should make on ADI ?

Regards,
Baz

 

[Bramante M Perkasa]

I'll check it tonight Barrie, will let you know ASAP.

Bram

Hi Bram,

Well .... MY D7ug emits TWO flashes on ADI. (just checked) Always
has done so too, as I remember.

Of course, I have no way of knowing whether that's right or not. It
might be faulty --- might ALWAYS have been faulty. Hmmmm. Thanks
????

(As it happens, I rarely use the built in flash -- mostly for a
tiny 'dab' of fill.)

Anyone here able to clarify how many flashes a D7 should make on ADI ?

Regards,
Baz

 

[Ed Starkey]

ADI and TTL will both preflash, so I suggest use of manual at 1/16 as someone else has stated. I also think shutter speed can be bumped up to 1/350 or 1/500 if the camera is being handheld (depends on flash duration) to get an ultra sharp picture!!

Seems he is overexposing until he goes to 1/1500 which makes sense as most flash tubes output around 1/700 sec. pulse.

It seems he's doing everything right!!!

I'm as puzzled as the rest of u guys!!!!

Ed

 

[hwwong]

I've just had a thought, which I think may be the possible reason of my overexposed pictures:

I set the power of the built-in flash to 1/4 and didn't use any softer and bouncer when I was taking the overexposed pictures. I shot at a short distance from the model. When I set the shutter speed to higher speed like 1/1500, the exposure was better. That means the 1/4 built-in flash was too strong and made the pictures overexposed when I was using a shutter speed of 1/250. But a shutter speed of 1/1500 can just compensate the high output of the built-in flash so that the exposure turned out ok. I think it is most likely the case because theoretically, the exposure of the pictures should stay the same at whatever shutter speed is used in studio photography. So the only factor that causes the overexposure should the built-in flash.

Do you think so?

Henry

 

[JusGene]

AS I BEST RECALL; the manual states (and I confirmed elsewhere) that the D-7 has a pre-flash for the TTL and ADI. I did the D-7UG(upgrade) and haven't seen a difference to that regard. I do enjoy the other added fractional flash speeds to trigger slaves, rather than the TOO expensive PCT-100 add-on.

Thanks for your response Barrie, by the way I use 7Hi and 7i (there
are four in my house at the moment,

http://forums.dpreview.com/forums/read.asp?forum=1024&message=5638114 ). Correct me if I am wrong, but I thought only preflash mode (not ADI) emits preflash, at least with the 7i and 7Hi?

The fractional speed flash under manual setting with studio slave flash should capture correctly if settings follow a correct metering. "AUTO ISO" could be a MAJOR no-no!!

Best,

Gene

Regards,
Bram

--
Hi Bram,

Well .... MY D7ug emits TWO flashes on ADI. (just checked) Always
has done so too, as I remember.

Of course, I have no way of knowing whether that's right or not. It
might be faulty --- might ALWAYS have been faulty. Hmmmm. Thanks
????

(As it happens, I rarely use the built in flash -- mostly for a
tiny 'dab' of fill.)

Anyone here able to clarify how many flashes a D7 should make on ADI ?

Regards,
Baz

 

[Barrie Davis]

I've just had a thought, which I think may be the possible reason
of my overexposed pictures:

I set the power of the built-in flash to 1/4 and didn't use any
softer and bouncer when I was taking the overexposed pictures. I
shot at a short distance from the model. When I set the shutter
speed to higher speed like 1/1500, the exposure was better. That
means the 1/4 built-in flash was too strong and made the pictures
overexposed when I was using a shutter speed of 1/250. But a
shutter speed of 1/1500 can just compensate the high output of the
built-in flash so that the exposure turned out ok. I think it is
most likely the case because theoretically, the exposure of the
pictures should stay the same at whatever shutter speed is used in
studio photography. So the only factor that causes the overexposure
should the built-in flash.

Do you think so?

Henry

That may very well be the answer, Henry.

In fact, it may be a combination of factors.

A little overexposure from the studio lights, which might have been as much as one whole stop for some of the shots. Then an additional top-up of light from the front from the built in flash. Even a small amount of light, when hitting subject from the front, can have a big effect. Also the 1/4 power is 'fixed' and does not reduce with small distances as auto flash does.

Here is a tip:-

To use the pop-up to trigger studio flash and NOT have any actual light come out is easy. Put an "infra red passing" filter over the flash window. Flash units emit a quantity of infra red AND the slave cells in the flash heads are very sensitive to it and will trigger reliably, even on 1/16 power (usually!).

The best part is this. An Infra Red passing filter can be made out of any old piece of transparency film (E6 process) which has been processed out, but was never exposed. The film leader from a roll of slide film, (the BLACK bit that the pro labs throw away) is ideal. Scrounge some from your local processing lab and tape it over your pop-up flash --- instant infra red trigger system at zero cost!

I am glad we got there in the end, Henry. We couldn't have done it without you. ;-)

Regards,
Baz

 

[hwwong]

Thank you Barrie for your good suggestion of using a E6-processed but unexposed positive film. I will definitely try this method next time. Your help throughout this problem solving process is greatly appreciated. Thanks again.

Henry

I've just had a thought, which I think may be the possible reason
of my overexposed pictures:

I set the power of the built-in flash to 1/4 and didn't use any
softer and bouncer when I was taking the overexposed pictures. I
shot at a short distance from the model. When I set the shutter
speed to higher speed like 1/1500, the exposure was better. That
means the 1/4 built-in flash was too strong and made the pictures
overexposed when I was using a shutter speed of 1/250. But a
shutter speed of 1/1500 can just compensate the high output of the
built-in flash so that the exposure turned out ok. I think it is
most likely the case because theoretically, the exposure of the
pictures should stay the same at whatever shutter speed is used in
studio photography. So the only factor that causes the overexposure
should the built-in flash.

Do you think so?

Henry

That may very well be the answer, Henry.

In fact, it may be a combination of factors.

A little overexposure from the studio lights, which might have been
as much as one whole stop for some of the shots. Then an additional
top-up of light from the front from the built in flash. Even a
small amount of light, when hitting subject from the front, can
have a big effect. Also the 1/4 power is 'fixed' and does not
reduce with small distances as auto flash does.

Here is a tip:-

To use the pop-up to trigger studio flash and NOT have any actual
light come out is easy. Put an "infra red passing" filter over the
flash window. Flash units emit a quantity of infra red AND the
slave cells in the flash heads are very sensitive to it and will
trigger reliably, even on 1/16 power (usually!).

The best part is this. An Infra Red passing filter can be made out
of any old piece of transparency film (E6 process) which has been
processed out, but was never exposed. The film leader from a roll
of slide film, (the BLACK bit that the pro labs throw away) is
ideal. Scrounge some from your local processing lab and tape it
over your pop-up flash --- instant infra red trigger system at zero
cost!

I am glad we got there in the end, Henry. We couldn't have done it
without you. ;-)

Regards,
Baz