Exposure Question - advice

Rockshifter

Rockshifter

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Charles
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Hi All
Looking for some advice / info

I've been playing around at my mate's back room studio - couple of cheap lights.
Problem is I'm shooting with a prime 85, 1.8 and at max f16 lens goes to, I get totally over-exposed shot.
I'm at the lowest ISO, fastest Shutter Sync speed and lights are at lowest power settings and as far away as can get.
Are you guys using HD filters to reduce light or are regular mid-range lights able to step down to allow proper exposure ?
 
Check ISO and what are the lights set to?
 
admirable said:
Check ISO and what are the lights set to?
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Hi Brigadoon

ISO is at lowest setting and lights are at lowest power.
Can only get a properly exposed shot if I use a cheap zoom that goes to f25 or there abouts.
My prime only goes to f16.
 
That sounds very very wrong. No studio light at it's lowest setting will give you those f numbers unless its bare and inches away from the subject.
 
Are the blades sticking open in the lens?
 
I'm wondering why the lens goes to f/16 and not f/22?
 
Are you sure EVERYTHING auto is off? Set your shutter to 1/250th sec iso 100.
Turn one light on and to its lowest setting, and point it at the wall. Now work through the aperture settings taking a shot for each one aiming at the light on the wall. You should now have a range of images from under exposed to over exposed.
If your not getting this your lens might be stuck at a specific aperture. Check the contacts for crud if its digital and for sticky blades.
Failing that you must have fusion reactors running your lights
 
The23rdman said:
That sounds very very wrong. No studio light at it's lowest setting will give you those f numbers unless its bare and inches away from the subject.
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As above.
The likely problems are that the lights just don't adjust low enough - cheap lights may only adjust down to 1/16th or even 1/8th power, and I have personally tested lights that state that they adjust down to 1/8th but in reality only adjust down to about 1/3rd - I say 'about' because they are different every time.

If you have a full frame camera you should really try not to use an aperture smaller than f/16, regardless of what the lens can stop down to, otherwise you will get a general loss of sharpness due to diffraction limitation. If you have a cropped sensor camera then your smallest usable aperture is around f/11. A compact camera, with an even smaller sensor, is even more limited.

Yes, you can use neutral density gels over the lights, or a neutral density filter over the lens. 0.9 (3 stop) is generally the best choice.
 
Hi All
First thanks to all for taking time to offer advice.

Answer to some questions:
Camera – Full frame Nikon D700
Lens – 85mm, 1.8D (Minimum aperture f16)
Didn’t take note of make of (Cheap) lights (Will check next week as my friend is away on holiday)

I haven’t asked if OK to post shots taken, however to try to resolve this / work out solution I’ll post one pic taken and leave it up for a couple of days.

This is the best I've been able to get - moving lights as far ass possible and as wide open without blowing.
I didn't want to shoot faster than 1/125 to avoid sync probs - is 250th, as suggested possible without problems ?
I'm wanting to get a soft look on the skin and use the lens wide open.

Best result - shooting raw (No processing, straight out camera)

1/125, f/5, ISO 100, 85mm, WB - Flash
test110.jpg


As you can see from these settings I have little room to experiment with settings.
 
Garry Edwards said:
As above.
The likely problems are that the lights...

If you have a full frame camera you should really try not to use an aperture smaller than f/16, regardless of what the lens can stop down to, otherwise you will get a general loss of sharpness due to diffraction limitation. .
Click to expand...

Thanks for input Garry
Hoping it is mainly lights not stepping down enough.
Not really wanting to go down filter route.

Can you clarify - is it mainly the softbox / lighting which will give skin a smooth, soft look ?

Maybe you could recommend one of your video.
 
Simon photo said:
Are you sure EVERYTHING auto is off? Set your shutter to 1/250th sec iso 100.
Turn one light on and to its lowest setting, and point it at the wall. Now work through the aperture settings taking a shot for each one aiming at the light on the wall. You should now have a range of images from under exposed to over exposed.
If your not getting this your lens might be stuck at a specific aperture. Check the contacts for crud if its digital and for sticky blades.
Failing that you must have fusion reactors running your lights
Click to expand...

Hi Simon
Not my lights but may have a teat as suggested.
Have checked lens and works fine.

Cheers
 
Generally speaking, if you want soft light from your soft box, you should place it as close to your subject as possible. This is assuming your soft box is not very big.
 
t43er said:
Generally speaking, if you want soft light from your soft box, you should place it as close to your subject as possible. This is assuming your soft box is not very big.
Click to expand...

Cheers Edmund
Thought that was the case, however as above too much power to do that without blowing exposure.
 
You can stop down your aperture to f8 or even f11. Else the only solution I can think of is using nd filter which was mentioned above.
 
Rockshifter said:
Lights in softbox and about 4 - 5 feet away.
Click to expand...

In that case, as Garry says, the lights are probably just crap. You'll be better off shooting wide open with the modelling light instead.
 
Rockshifter said:
Lights in softbox and about 4 - 5 feet away.
Click to expand...

Does the softbox have a diffuser front on it? The light in the pic looks very hard, not like a softbox. That would explain the exposure issue, too.
 
HoppyUK said:
Does the softbox have a diffuser front on it? The light in the pic looks very hard, not like a softbox. That would explain the exposure issue, too.
Click to expand...

That's true. I didn't look at the shot as I'm on my phone.
 
Charles, sorry I'm confused, you originally said you were getting overexposure with lights at lowest setting and f16, yet you've posted a perfectly exposed shot at f5.

I dont think you'll find even the most expensive strobes will allow you to shoot at close range lower than f4 ish, I know mine don't!

As has been said, either just use the modelling light with flash turned off, or an ND filter on lens or lights :)
 
Take a look at your auto ISO setting on your D700, something very similar happened to me quite recently, i set the camera to ISO 200, but didn't realise, i hadn't turned the auto setting to off (it's normally on unless i'm doing studio photography) i took a few shots and wondered what the hell was going on, then i checked again, and was kicking myself after :bonk: :D
 
treeman said:
Charles, sorry I'm confused, you originally said you were getting overexposure with lights at lowest setting and f16, yet you've posted a perfectly exposed shot at f5.

I dont think you'll find even the most expensive strobes will allow you to shoot at close range lower than f4 ish, I know mine don't!

As has been said, either just use the modelling light with flash turned off, or an ND filter on lens or lights :)
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Sorry Mark

You are right.
I should have said I get over=exposed shots at f16 when I try to use my friend's two lights at lowest settings.
 
The23rdman said:
That's true. I didn't look at the shot as I'm on my phone.
Click to expand...

Yes, softboxes have diffusers attached.

TG. said:
Take a look at your auto ISO setting on your D700, something very similar happened to me quite recently, i set the camera to ISO 200, but didn't realise, i hadn't turned the auto setting to off (it's normally on unless i'm doing studio photography) i took a few shots and wondered what the hell was going on, then i checked again, and was kicking myself after :bonk: :D
Click to expand...
Yes this actually happened on my first few shots when I had the ISO on auto and shots were well totally over-exposed, however after setting to manual I had to set to ISO 100 which helped a lot, but still was on the limit of getting a correct exposure.

From what's been said I think I'm not doing anything crazy and the problem seems to be the lights not having a low enough setting to give me enough leeway to be a little creative.

Thanks for all the advice.
 
Last edited:
I have used a couple of 500w Bowens just a few feet from my subject and can quite comfortably shoot at f/11 without overexposing, and that's with the lights a few clicks away from their minimum setting, so it does very much sound like your lights are the problem.
 
Scarecrow said:
I have used a couple of 500w Bowens just a few feet from my subject and can quite comfortably shoot at f/11 without overexposing, and that's with the lights a few clicks away from their minimum setting, so it does very much sound like your lights are the problem.
Click to expand...

Cheers Derek
Pretty much looks like the cheap lights - Cheers√
 
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