Getting "enough light" for LF portraiture

[StoneNYC]

is that the point of making a portrait, to put it on a large computer screen so people can zoom in ?
if that is the reason to do it, it seems like an utter waste of time ..
no matter the image, someone is going to find some sort of flaw ..

The OP...

I've been trying my hand at large format portraits and have been struggling to get fast enough shutter speeds to keep subject motion under control.

My experience is primarily 35mm/DSLR, where it's pretty easy to take portraits in any lighting environment, due to the greater aperture and ISO flexibility.

The OP is used to digital, and is struggling with motion blur, this is because they are dealing with the perception of what I'm addressing. The difference between noticeable motion blur of an 8x10 or smaller contact, vs an enlarged image many times enlarged to notice the motion blur. I'm only addressing this because of what the OP describes as a problem.

[Kodachrome25]

I get dynamite 20x24's from medium format negs and can really concentrate on making great emotionally driven portraits if I so choose. I have done a few portraits with my 4x5 but it is probably about 3rd in line for that kind of work.

Put the power of the image over the gear used and you will win everytime in my book.

[blueribbontea]

i get dynamite 20x24's from medium format negs and can really concentrate on making great emotionally driven portraits if i so choose. I have done a few portraits with my 4x5 but it is probably about 3rd in line for that kind of work.

Put the power of the image over the gear used and you will win everytime in my book.

amen...

[ImSoNegative]

You should really look into understanding flash/ambient exposure control...once you understand that you'll be off making work confidently.


Sounds like your flash overpowered any ambient light in your last test.

there are some really good videos on youtube covering this subject. the meter I have is the sekonic L358, what I do is meter my ambient, and say my ambient fstop is 5.6, I just zero my flash to 5.6 and the meter gives me a ratio of flash to ambient and then I will adjust my shutter speed accordingly to get the ratio I want.

[ghostcount]

If your meter doesn't calculate the contribution for you, a couple of multiplication, an addition and a division will get your flash contribution.

The flash to ambient ratio is,

(flash contribution)^2 / [(flash contribution)^2 + (ambient contribution)^2 ]

For example, your metered flash reads 8 and your metered ambient reads 11

8^2 = 64

11^2 = 121

64/(64+121) = 0.345 or 34.5% comes from the flash. Easy, peasy and everyone has a calculator in their phone these days.

As a note, the ambient contribution is dependent on the shutter speed. So if you are too lazy to change the flash power and your ambient has the latitude, change your shutter speed and the ambient contribution becomes a variable. No need to "give up" anything. In fact, getting the catch lights in the subject's eyes from the flash is rather nice.

[jnantz]

The OP is used to digital, and is struggling with motion blur, this is because they are dealing with the perception of what I'm addressing. The difference between noticeable motion blur of an 8x10 or smaller contact, vs an enlarged image many times enlarged to notice the motion blur. I'm only addressing this because of what the OP describes as a problem.

just in case you missed what he wrote on page 4 just before your post ---

Thanks John, that is a lot of good advice and interesting thoughts.

Yes, my normal workflow is drum scanning the 4x5s and editing and printing digitally at 16x20. I would not call that a massive enlargement, but pretty big I guess at 4x the dimensions and 16x the area.

I may print bigger if I end up with a good portfolio, and have a reason to print 32x40 or something like that. I don't know. But I'd like to given the opportunity.

==

adam

not really sure what sorts of portraits you hope to ( or do ) make ..
whatever it might be, good luck ( and don't let the turkeys get you down )!

john

btw the attached was done with a cheap little tlr on a tripod (not 4x5), and a sunpack /pc cable off camera
the one prevciously posted ( #2 i think at the furniture shop ) done the same with with a 4x5 -- on tripod
and a lumedyne ... both were taken at about 1/60 or 1/30S ... no blur, real people, not models, and easily enlarged really big.

[StoneNYC]

If your meter doesn't calculate the contribution for you, a couple of multiplication, an addition and a division will get your flash contribution.

The flash to ambient ratio is,

(flash contribution)^2 / [(flash contribution)^2 + (ambient contribution)^2 ]

For example, your metered flash reads 8 and your metered ambient reads 11

8^2 = 64

11^2 = 121

64/(64+121) = 0.345 or 34.5% comes from the flash. Easy, peasy and everyone has a calculator in their phone these days.

As a note, the ambient contribution is dependent on the shutter speed. So if you are too lazy to change the flash power and your ambient has the latitude, change your shutter speed and the ambient contribution becomes a variable. No need to "give up" anything. In fact, getting the catch lights in the subject's eyes from the flash is rather nice.

Luckily my meter tells me the percentage on the screen

[Corran]

I get dynamite 20x24's from medium format negs and can really concentrate on making great emotionally driven portraits if I so choose. I have done a few portraits with my 4x5 but it is probably about 3rd in line for that kind of work.

Put the power of the image over the gear used and you will win everytime in my book.

Hey, this might be a good start to another thread. If this were 100% true, why do you keep beating the anti-digital drum? If it's all about the image and not the gear you use, digital wins hands-down.

Just playing devil's advocate here. Interested to hear what you think.

[analoguey]

Hey, this might be a good start to another thread. If this were 100% true, why do you keep beating the anti-digital drum? If it's all about the image and not the gear you use, digital wins hands-down.

Just playing devil's advocate here. Interested to hear what you think.

I know it was addressed to someone else but the transition from 'in-Focus' to oof areas is much sharper and more clearly defined with Digital capture.

That in itself is good enough reason to shoot film.

And I'm sure there's already 250000 mentions of 'why film ' already in the Forum.

[analoguey]

That said, back to the original topic. The OP would probably benefit from practicing more off camera flash in smaller formats and then moving onto the bigger format.
The principles are the same. Ditto calculations.
Easier to test the learning out on smaller formats and then move upwards.