Help with studio photography

[kry10]

Hi all.

As you might have seen in a previous post, I have access to some Bowens 500GM lights, only 2 of them as one of the bulbs has blown in the third.

I now have a remote wireless trigger for the flash, which works perfectly, what I am struggling with is this.....

I know that I have to have the camera shutter speed to 1/200 (it's a Canon 1100D), but, that means a fair bit of light will reach the sensor, unless I close the aperture to f22 or there abouts, I cannot use a wide aperture of f2, which, I would have thought was what you wanted for portrait photography to create a shallow DoF, so, what do I do ?

I was using a two flash set up, one to the left and up high for the hair light with a brolley as a diffuser (shoot through) and the second fill in light on the right with another brolley as a diffuser (shoot through).

I have tried turning the flash power down, but, it's still pretty bright and causing blown out images with very strong highlights.

Would something like an ND filter help with the problem or is there something that I am doing wrong ?

 

[Garry Edwards]

You don't have to have the shutter speed set to 1/200th, that's just the shortest shutter speed that will work with most Canon cameras - it's actually a bit risky having it that high, most of us just use 1/125th.

but, that means a fair bit of light will reach the sensor

Only if there is a very high level of ambient light in the studio, e.g. sunlight streaming in through the windows. If there is, block out that unwanted light.

This is what you need to do to find out whether ambient light is causing a real problem or not...
1. Set up the shot to give you an acceptable exposure with flash.
2. Take a shot without the flash.
3. See whether or not there is enough of an image on your camera screen to cause a problem. There shouldn't be.

I have tried turning the flash power down, but, it's still pretty bright and causing blown out images with very strong highlights.

Which lights are these? Modern lights can be adjusted down to at least 1/16th of the full power. If your lights are very old, you may not have enough adjustments for your needs. Bear in mind that you should be able to set a pretty low ISO on your camera, this needs to be done anyway, and especially if there is too much lighting power.

Would something like an ND filter help with the problem

Yes, that would be a big help. ND filters are common in 0.3, 0.6, 0.9 and 1.2 = 1 stop, 2 stops, 3 stops, 4 stops. If you have a pro Nikon body with a fast lens you should be able to get away with a 1.2 (4 stop) filter
If not, then your camera probably won't autofocus and you may be limited to either a 2 or a 3 stop - it depends on the body and the lens.

 

[kry10]

Thanks for the advice so far.

The lights are Bowens 500GM's and the camera is a Canon 1100D, your right about the ambient light, the problem is, we was in the large room which is one of the rooms with lots of natural light, hopefully we will be able to block out the light in some way.

The reason I chose 1/200 shutter speed is because that seemed to give the best result.

So, in theory, if I get a reasonably dark room with no natural light, use a shutter speed of 1/125 and use an aperture of f2, will I need the ND filter ?

 

[Garry Edwards]

So, in theory, if I get a reasonably dark room with no natural light, use a shutter speed of 1/125 and use an aperture of f2, will I need the ND filter ?

Yes

 

[alexam]

Thanks for the advice so far.

The lights are Bowens 500GM's and the camera is a Canon 1100D, your right about the ambient light, the problem is, we was in the large room which is one of the rooms with lots of natural light, hopefully we will be able to block out the light in some way.

The reason I chose 1/200 shutter speed is because that seemed to give the best result.

So, in theory, if I get a reasonably dark room with no natural light, use a shutter speed of 1/125 and use an aperture of f2, will I need the ND filter ?

Does the lens on your camera go as low as f2 ? Portrait shots are often taken at between F5.6 and f10 as the aperture is adjusted according to the depth of focus you require for the particular shot. At f2 the depth of focus will be very small.
Malcolm

PS. It may help if you complete your Profile information with name and what you have in your camera bag.

 

[Phil V]

I just wonder if you've got the ISO too high? You should be able to get middling apertures at comfortable shooting distances with 100 ISO.

The other thing is that ina studio environment portraits rarely need shallow DoF.

Outside the studio we tend to shoot wide apertures simply to render the background as an OoF blur, in the studio we generally just create a clean background using a background. This means we can shoot at f5.6 or f8 and still get clean portraits.

But like Garry said, you'll need an ND filter to get F2.

 

[kry10]

I have made the additions to my camera bag section on my profile.

I am shooting at ISO of 100, the lens I was using was my Helios 44M as it has a wide aperture of f2.

So, an aperture of f5.6 should give a shallow enough depth of field, my question is though, how far away from the backdrop should the model be, I read somewhere that about a meter is the right distance, is that right ?

Another question I have is this, the Bowens lights have modelling lamps, when the photograph is taken, do the modelling lamps contribute to the brightness of the flash or can I have them turned up pretty high ?

The flash setting is as follows - Full to 1/32 - 5 stops.

 

[Garry Edwards]

The subject should generally be as far away from the background as you can manage. The greater the distance, the easier it is to avoid problems

To a limited extent, bright modelling lamps can make a difference if the flash power setting is very low, so if you're going to shoot at the lowest possible power you may need to switch the modelling lamps off, or at least down.

Of course, if you really want to shoot at f/2 then you could just use the modelling lamps instead of the flash.

 

[sk66]

Yes

Um, No.
You EITHER need low ambient OR the ND's. The problem with ND's is that they also kill the flash which requires you run them at higher output.

Why do you feel you need a wide aperture for portrait work in a studio? In a studio you have control of the BG and subject position so you don't *need* it for separation... I can see where you might want to use it occasionally for creative effect.

If you use a 100mm lens @ f/16 from 5ft (headshot) your DOF is ~1ft total. @f/8 it would be ~2ft. Or from 10ft (3/4 shot) it would also be ~2ft @f/16.

 

[Garry Edwards]

Um, No.
You EITHER need low ambient OR the ND's. The problem with ND's is that they also kill the flash which requires you run them at higher output.

???
The whole idea is that the OP wants to shoot at f/2

 

[sk66]

So, in theory, if I get a reasonably dark room with no natural light, use a shutter speed of 1/125 and use an aperture of f2, will I need the ND filter ?

???
The whole idea is that the OP wants to shoot at f/2

The first quote is what you replied "yes" to.... I don't think you need a ND in a "reasonably dark" room with no natural ambient light, even at f/2.

I just checked because I hate to say things that are wrong/misleading...In my LR right now it is bright enough to read in, it has 3 sides with windows but no direct sunlight at the moment (one side has an 8ft window). I would consider it "averagely lit." Right now it meters white as f/2 1/125 ISO 640. So at f/2 1/125 ISO 100 it would require ~2 1/2 stops of light from a strobe. At f/2 1/200 ISO 100 it would require ~3 1/2 stops of light. That's approaching the ability to turn a white BG black.

But I still question the use of f/2 in a studio setting....

 

[HoppyUK]

The first quote is what you replied "yes" to.... I don't think you need a ND in a "reasonably dark" room with no natural ambient light, even at f/2.

I just checked because I hate to say things that are wrong/misleading...In my LR right now it is bright enough to read in, it has 3 sides with windows but no direct sunlight at the moment (one side has an 8ft window). I would consider it "averagely lit." Right now it meters white as f/2 1/125 ISO 640. So at f/2 1/125 ISO 100 it would require ~2 1/2 stops of light from a strobe. At f/2 1/200 ISO 100 it would require ~3 1/2 stops of light. That's approaching the ability to turn a white BG black.

But I still question the use of f/2 in a studio setting....

The OP has 500Ws of studio flash and wants to shoot at f/2. There is no way they will turn down low enough, and even if they did, even the slightest amount of ambient light would have an influence. An ND filter fixes both problems.

The alternative is to forget the flash and just shoot by the modelling lights, though that would require a compeltely darkened room and an ISO push to get a safe shutter speed.

 

[kry10]

It's okay, as someone said, an f5.6 should be suitable for what I need, I will keep working at it, its all a learning process.

 

[Bayrunner]

I now have a remote wireless trigger for the flash, which works perfectly, what I am struggling with is this.....

I know that I have to have the camera shutter speed to 1/200 (it's a Canon 1100D), but, that means a fair bit of light will reach the sensor....

Remember that the flash duration is measured in 1/1000ths of a second, so unless you have large amounts of ambient light the same amount of light will be hitting the sensor regardless of shutter speed.

Where the 1/200th comes is is that above that the flash sync process becomes too slow to allow the shutter to clear the aperture

 

[canonlad]

Don't forget that DOF is reduced the nearer you are to your subject, F8 is not the same at four feet as it is in a landscape photograph. I suffer the same problems that you do in my small studio. If you are in a large room why not move the lights back away from the subject. That way less light will fall onto your subject and your DOF will be reduced. you could buy ND filters for the flash heads or one for the camera.
All a bit random, I know, but I hope it helps.

 

[Phil V]

Don't forget that DOF is reduced the nearer you are to your subject, F8 is not the same at four feet as it is in a landscape photograph. I suffer the same problems that you do in my small studio. If you are in a large room why not move the lights back away from the subject. That way less light will fall onto your subject and your DOF will be reduced. you could buy ND filters for the flash heads or one for the camera.
All a bit random, I know, but I hope it helps.

The problem with moving the lights is that it changes their relative size, and so the shadow quality.

Given the reason for studio lighting is to control the quality of light its a bit self defeating to move the lights for exposure reasons.

 

[sk66]

The OP has 500Ws of studio flash and wants to shoot at f/2. There is no way they will turn down low enough, and even if they did, even the slightest amount of ambient light would have an influence. An ND filter fixes both problems.

The alternative is to forget the flash and just shoot by the modelling lights, though that would require a compeltely darkened room and an ISO push to get a safe shutter speed.

Well, Ws' aren't directly comparable, but apparently those strobes do have a pretty high GN (80m?). With one stop of diffusion and at 1/32 power (6 stops less power total/GN 10.6m) it's around 5m @f2...That's probably too far and certainly not ideal for a shoot thru umbrella. So yeah, I was wrong.

So what else could we do? One could buy ND's. They are rather expensive for good ones, but probably a very good idea if you're going to be using strobes outdoors... or if you're stuck with these strobes long term.

We could move the lights even further away...bad choice...not if we can help it; might not even be an option.

We could add additional diffusion to our modifier. That might be an option using a sheet or something. One stop of added diffusion would cut the power/working distance down to ~3.5m. 2stops= ~2.5m

We could change "how" we use the light... This has added consequences which may not be desirable, but perhaps it would work to use the main light bounced in a smaller studio; effectively turning the entire wall/ceiling into a huge softbox. By bouncing we eat up a lot more working distance/power of the light, and we loose another stop or two due to scatter.

Or we just stop down the aperture some more...

 

[Garry Edwards]

Using a ND filter over the lens is exactly what I suggested. Yes, he could stick ND gels over the light sources, and this is in many ways a better option because it's selective, but has the disadvantage that the effective power of the modelling lamps is effectively reduced.

Bouncing the light off the ceiling? Yes, in terms of power, but lighting is all about controlling light and shadows, and doing that and using things such as shoot through umbrellas, will take the OP in the opposite and wrong direction.

No, adding diffusion doesn't reduce the amount of light in real terms, it just spreads it around - there is in reality no such animal as one stop (for example) of diffusion - just an effective 50% spread of light at a given distance, resulting in an effective power loss at that distance of 1 stop.

Hence my suggestion of a ND filter.

 

[sk66]

Bouncing the light off the ceiling? Yes, in terms of power, but lighting is all about controlling light and shadows, and doing that and using things such as shoot through umbrellas, will take the OP in the opposite and wrong direction.

Are you saying a smaller bare source is better than a larger diffused one? How is a light modifier "the wrong direction?" That's completely contrary for most forms of lighting.
Size and direction are major factors in the quality/character of light and controlling shadows. The main disadvantage of bouncing the light that I can envision would be a loss of controlled catchlights. Directional control would probably be a little more difficult as well. Otherwise it is (could be) turning that entire section of the room into a huge softbox. You then have control over subject position for refinements.

Am I just not understanding something?

No, adding diffusion doesn't reduce the amount of light in real terms, it just spreads it around - there is in reality no such animal as one stop (for example) of diffusion - just an effective 50% spread of light at a given distance, resulting in an effective power loss at that distance of 1 stop.

Technically, you are correct in that light has to be converted into something else (i.e. heat) in order to be "consumed/reduced". But diffusion material doesn't just "spread" the light forward, it also reflects it backwards. It still results in an "effective" reduction of power. 1 stop is 1 stop regardless of the distance, although distance also affects effective power significantly.

Hence my suggestion of a ND filter

I completely understand the ND for the camera considering the GN of the strobes in use...I already admitted that part. But using ND's then would probably not require also having a dark room with no natural light. I suppose there is variability in that as far as how much ND reduction is available.

As I understand it, these are borrowed strobes. I wouldn't want to commit to purchasing fairly expensive ND's for just this one time use. And I wouldn't recommend them as a solution in that case either...not if there is a way around it. ND's are very useful tools with other purposes, so I own them anyways.

 

[Garry Edwards]

Are you saying a smaller bare source is better than a larger diffused one? How is a light modifier "the wrong direction?" That's completely contrary for most forms of lighting.
Size and direction are major factors in the quality/character of light and controlling shadows. The main disadvantage of bouncing the light that I can envision would be a loss of controlled catchlights. Directional control would probably be a little more difficult as well. Otherwise it is (could be) turning that entire section of the room into a huge softbox. You then have control over subject position for refinements.

Am I just not understanding something?

I'm guessing that I just didn't make myself clear. GBS once famously described Americans and British as "Two great nations divided by a common language" By wrong direction, I meant that bouncing light off of a ceiling just to reduce the effective quantity is a poor choice.

This doesn't of course mean that it is always wrong to bounce the light off of a ceiling, sometimes that overhead, soft light is exactly what is wanted. But it is a very bad way of reducing the effective power, because it kills the lighting control. If that kind of lighting was all that the OP required he could produce that result with hotshoe flashes bounced off the ceiling.

Technically, you are correct in that light has to be converted into something else (i.e. heat) in order to be "consumed/reduced". But diffusion material doesn't just "spread" the light forward, it also reflects it backwards. It still results in an "effective" reduction of power. 1 stop is 1 stop regardless of the distance, although distance also affects effective power significantly.

Yes and no, but mainly no. Yes, some of that light is bounced back - but where to? If it's a softbox or a beauty dish then it bounces back then bounces forward, some of it continues going forward, a little of it bounces back and then forward again, ad infinitum. It all ends up going forward, travelling at c

The point I was trying to make, and I am absolutely right, is that the main function of an extra diffuser is to spread the energy (in this case light) over a larger area. The further it has to travel, the more the energy is spread and the greater the apparent "loss". Therefore there is no such animal as a "1 stop diffuser", just a "1 stop diffuser at a distance of X".

I completely understand the ND for the camera considering the GN of the strobes in use...I already admitted that part. But using ND's then would probably not require also having a dark room with no natural light. I suppose there is variability in that as far as how much ND reduction is available.

There is a limit, it's a practical one. People who have consumer bodies and kit lenses can't use strong ND filters and still autofocus, and even people who have pro bodies and wide aperture lenses are limited, in practical terms, to 1.2. Even though 10 stop ND filters are available, and even though variable density ones are available, even though the IQ has been poor on the only one that I tested.