Strobe Power for 4X5

laroygreen

Member
Joined
May 8, 2011
Messages
111
Location
Trinidad and Tobago
Format
Multi Format
Good day,

I have been using 2 Alienbee B800 (320WS) flashes for a few years now with my DSLR, but I want to start doing portraits with my 4X5 camera. I plan to use Kodak Portra 400 film and I was wondering (roughly) if my flashes are powerful enough (18% grey looks 18% grey)?

My typical shot is 1-2 persons, with 1 flash going through a softbox just outside the frame of the photo (no more than 6ft away), with the second strobe used for separation/background lighting either with a reflector or through an umbrella - I may use window light as well, if it is strong enough.

I am guessing for portraits on 4x5, F16-F22 would be where I want to be (not a big fan of super shallow depth of field).

I may invest in another flash soon, however, I like the B800 for their compactness, as I do plan to throw everything in a Kelty Redwing 50 (tried it, works great) so that I can move around (I typically take pictures at a friends home or some other interior space).
 

pgomena

Member
Joined
Jun 25, 2003
Messages
1,391
Location
Portland, Or
Set your *slr to 400iso at f/16 and f/22 and see what happens. Better yet, do it in a film SLR with 400iso film, since digital and film iso designations are not an exact match.

Some of the answer to your question also may depend on the lens focal length you intend to use with your 4x5 camera. At 6 feet, you're at the edge of needing to figure bellows extension factor into your exposure with a 210mm lens, which is a good basic portrait focal length. And, if you're accustomed to working close-and-tight to your subjects, you may find you need to spread your lighting setup out a little in order to make room for the bigger camera or you may have to move the camera back a ways and move the lights out of the scene.

There are a lot of variables at work here, so it's a little tough to make a guess. I personally would not want to have a main light with less than 800w/s in a LF portrait setup at f/16. You might find you can work at f/11 if you're careful with focus and camera movements.

Peter Gomena
 

Two23

Member
Joined
Jul 4, 2010
Messages
660
Location
South Dakota
Format
8x10 Format
I've been shooting Portra 400 lately in a 1951 Rolleiflex. I used two White Lightining X3200 monolights (1320ws each) and shot f8. I placed the lights about 100 ft. off the rail. Last night I again used the Rollei with Portra 400 and used only four Nikon SB-28 flash, placed 20 ft. off the rail. I was getting ISO 400 and f6.3. I think you'll be OK since you'll be shooting indoors and the light will reflect back onto your subject, and you will place the flash much closer than I can. Did I mention I photo freight trains running at track speed at night?


Kent in SD
 
OP
OP

laroygreen

Member
Joined
May 8, 2011
Messages
111
Location
Trinidad and Tobago
Format
Multi Format
I went through my archives, and found a few shots taken at f22, and it looked good at ISO 200 (default for my camera) with just one light at full power (these where from 2008 and I only had 1 strobe at the time). I also just did a test at ISO 400 with the flash at the back of a room (10'x15'), pointed at the ceiling (white), and I was able to get a good exposure.

So, it may still be a stretch as I wouldn't have any power in reserve, but it is workable.

Honestly, I am having doubts about using 4x5 for portraits. It can be done, and lots of people do it, but there are many challenges:

- Takes a relatively long time.
- Exposures are more expensive.
- Bulky to set up.
- Very limited in the types of images I can take.

But, it does have some massive advantages:

- I tend to be more careful and methodical, and as a result, my images look better to me.
- I have to plan to take pictures long before I actually take anything, so I have to be more pro-active and less lazy.

I have been considering using the 4X5 for landscapes and probably just going medium format for portraits, but I really don't want to spend any more money and also, looking through the big ground glass at your composition is beyond words.

Slightly off topic, but any advice?


@Two23 - I thought it was a typo when you said 100ft - thanks for clearing that up! Where can I view your images, very interested.
 

36cm2

Member
Joined
Aug 19, 2008
Messages
645
Location
Northeast U.
Format
Large Format
I feel most comfortable with LF in front of something large that doesn't move quickly. I feel most comfortable with portraits in back of something smaller that I can move quickly if I have to.

That's what I feel; it doesn't have to be what you feel. I think each format has its ideal subject and for me it's LF for landscape, MF for portraits and macro and 35 for sport and street.

As for your original question, get a main light at least 1000 w/s and work the rest of the lights from there, if you decide to stick with LF.

Best of luck,
Leo
 
OP
OP

laroygreen

Member
Joined
May 8, 2011
Messages
111
Location
Trinidad and Tobago
Format
Multi Format
Did some soul searching, and decided I want to stay with 4x5 for the moment. Sounds more serious than it really was, but I have a good DSLR that I enjoy using as well, so whenever using my Cambo isn't workable, I'll just use my DSLR - and I have no issues with that and if I need to get another more powerful strobe, I will at some point.

Thanks for all the help - and sorry for the nervous breakdown - was frightened by the cost for Polaroid 405 holders on eBay which shook my believe in humanity to the core
 
OP
OP

laroygreen

Member
Joined
May 8, 2011
Messages
111
Location
Trinidad and Tobago
Format
Multi Format
@Two23 - Really like! My father used to be a train driver and mechanic ("modern" diesel trains) and I've always loved them. Had a lot of trains where I grew up and no greater way to get around than travelling the island on a slow train, across hills, valleys, rivers, tunnels and along the coast - some of my best memories! As a side note, don't the drivers get alarmed when they see the strobe light, and then you emerging from the darkness?
 

Leigh B

Member
Joined
Jan 17, 2011
Messages
2,059
Location
Maryland, USA
Format
Multi Format
Power requirements for a strobe system depend only on the film speed and lens aperture.

For example, an exposure with a particular flash using ASA 100 film and f/22 will look exactly the same
regardless of film format or lens focal length.

- Leigh
 

Steve Smith

Member
Joined
May 3, 2006
Messages
9,110
Location
Ryde, Isle o
Format
Medium Format
laroygreen said:
As a side note, don't the drivers get alarmed when they see the strobe light, and then you emerging from the darkness?
Click to expand...

I wondered about this too. I suppose it must be a bit of a surprise to them but unlike someone driving on a road, they are not going to lose control and crash into a tree.


Steve.
 
OP
OP

laroygreen

Member
Joined
May 8, 2011
Messages
111
Location
Trinidad and Tobago
Format
Multi Format
If that happened to me, I'd file a UFO sighting - Unidentified Flashing Object ... Interesting work though, and they probably get a story to tell on the CB radio, and it may well turn into an urban myth over time.
 

daleeman

Member
Joined
Jul 17, 2008
Messages
1,150
Location
Homosassa, Florida
Format
Multi Format
I really enjoyed using my Alien Bees with my 4x5 and a 210 lens. I have two #800 alian bees with umbrellas and also gells and such. I also picked up an Adorama 160 watt little flash with a snoot and barndoors for some hair light and seperation from what ever background on a boom stand. Shoot most of my stuff at f22 and it is fine.

Also, yes it is slow but the sessions are fantastic. I would ask for 30 to 45 minutes to do a remote before the sitter was to get involved to get things in place and use my flash meter to check things out. Then I usually did 12 shots. The interactions with the sitter was wonderful. I got very good and getting them posed how I liked them, then I did a second stool for me to sit off camera with a longer release. I would engage them in conversation and they would relax, except for my repeated request not to slowch. Sessions were about 40 minutes. Then there was breakdown.

I really enjoy this every time it happens. Personnally I would like to bill myself as a special add-on to so many DSLR weding shooters to have me come in and work with the bride and groom just for this special true B&W experience. Reminds me of what great portrait photographers like Jane Reece used to be.
 

TheFlyingCamera

Membership Council
Advertiser
Joined
May 24, 2005
Messages
11,546
Location
Washington DC
Format
Multi Format
I was always very happy with my 750 w/s Calumet Travelites when shooting 4x5 in the studio, with a 210mm lens. They had more than enough oomph at about 5-6' from the subject (my studio was SMALL - my 10x12' dining room) to hit f16-22 in a 30x40 inch softbox. Your alienbees don't have the power to really do that, but you could probably get away with f11, especially if you bring your light in a little closer, and/or change your light modifier.
 

ParkerSmithPhoto

Member
Joined
Jan 16, 2010
Messages
1,685
Location
Atlanta, GA
Format
Medium Format
Just tested my White Lightning Ultra Zap 800 (330 watt seconds) -- full power at 10 feet, through a 48" octa light, ASA 400, got a nice crisp f16. I like my box to be just outside the shot when I shoot portraits, so I would generally have it much closer. You should have plenty of power with the bees.
 
OP
OP

laroygreen

Member
Joined
May 8, 2011
Messages
111
Location
Trinidad and Tobago
Format
Multi Format
Just as an FYI, I found this on the PCB website (makers of Alienbee flashes) and it matches up with my own results with my DSLR http://www.paulcbuff.com/output.php.

Those measurements are at ISO100, so I am right where I would typically need to be at ISO400, plus, I don't have any issues pushing the film 2 stops if needed (even if it isn't needed, like the look of it from time to time), so I should be OK until I can invest in more powerful strobes (no time soon!).
 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…