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Aimee C. Eisaman

Depth of Field with Studio Lights

One problem I seem to be having with my studio shots is that my DOF is very deep. I have these wrinkled backdrops, and even with my kid 4 to 5 feet in front of them, I'm seeing them clear as a bell. I'm shooting in manual mode with ISO 200, shutter speed 1/100 sec, F/14, focal length-55mm. I'm using an 18-55mm lens. I'm thinking I need to be shooting at a lower F-stop, but I can't seem to find the balance between that and my shutter speed to get correct exposure. I'll include a few examples of originals I have with these settings!

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March 09, 2009

- Carlton Ward

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Hi Aimee,
F/14 will allow more background clarity. Try opening up to f/7.1 or f/4 to give you a shallowr DOF and use a faster shutter speed like 1/250 or whatever your strobes are set to - and you may try using ISO100 as well.
Give this a try.
Carlton

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March 09, 2009

Aimee C. Eisaman

Thanks Carlton....I'll give it a whirl when I get my lights set back up! Can't leave them up in the living room with 3 little boys or they would be broken! :~) I'll have to check my camera, but I think after ISO 200 is .3 low .7 low or 1 low. Probably just Nikon jargon.....I'll try .3 low.

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March 09, 2009

- Dennis Flanagan

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Aimee, The lights have nothing to do with your DOF. The rules are the same as shooting with natural light.

Do you own a flash meter? It's a necessity for shooting with stobes. Then you set your key (main) light up to shoot for the apeture you desire. It can be achieved by either dialing down the power of your light for a smaller f/stop setting or moving the lights farther away.
using controlled lighting, use the lowest ISO your camera allows.

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March 09, 2009

Aimee C. Eisaman

My lights either go full power or half power so what I think I'm going to have to do is try moving them back. I'm working in a long narrow room so it's a tad complicated. I do not have a flash meter....on my list of things to get....it's a long list! LOL! I knew I had to use a smaller F/stop, but when I did...highlights were blown out and I already had my lights on half power. I think to learn what is going on I am going to have to practice using only 1 of my lights. I will try moving it around....thanks Dennis! Going to set them back up today after 2 of my kids are napping and work on sealing off the living room. Used to be able to do it with the couch, but the 2 year old figured out that he can just crawl under it to get in! And I'll have to set that ISO.....with my new camera it can go pretty low. I had never thought of that before.....why would I need a high ISO if I have tons of light and am setting the shutter speed myself anyway? Hmmmm.....learning already! :~)

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March 10, 2009

- Dennis Flanagan

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Remember that when you decrease your f-stop (wider apeture) you need to increase your shutter speed.

Do you have a reflector? You can make one easy enough with some cardboard and white paper, or use some crumpled aluminum foil. It can be used to fill in shadows in the absense of a fill flash.

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March 10, 2009

Aimee C. Eisaman

Yes....that is what I played around with last time, but if I increased the shutter speed too much I got a black screen because the shutter beat out the flash on my strobes! LOL! Guess my problem seems to be finding that happy medium! Yes I do have a reflector. I have not been using it because I find it impossible to hold it, the camera, and try to keep my kid from knocking down my lights! I really need an assistant or some adults to shoot!

Got my lights set up again and once it gets dark out I am going to play around with it. I have an idea I need to shoot by the end of the month for my clubs monthly theme and it is going to require a shallow DOF. I'll post my results soon!

Thanks so much again for all of your tips and ideas!

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March 10, 2009

Aimee C. Eisaman

Well my idea for my theme ended up going a different direction so I couldn't use it as an example of my struggles. I did, however, set up shop with a doll as a model. I played around a little and realized that the lights I have are really powerful! Too powerful for the small area I have them in. So I decided to start from the begining and unplug all the lights but one. The power pak has 2 settings...full power & half power. I have only ever used it on half power so I left it there. Took a few shots and still too much light. So I took out the white umbrella I was shooting thru and put on a reflector umbrella. This did help.

Okay on to the issue at hand! The lens I shoot with is an 18-55mm 3.5-5.6. I always end up shooting around 50mm so I set it to that. Put it on manual mode setting the ISO as low as it could go, setting the Ap to 5.6 which is as low as it would go, and setting the shutter speed to 1/400 sec. which gave me a picture with the shutter in it. Picture number 1 in my uploads. In order to get my shutter out of the shot I had to back the shutter speed down to 1/200 sec which gave me picture #2. This shot let way too much light in and blew the histogram out of the water! In picture number 3 I adjusted the Ap to 10 and got a shot with minimal blown out area, but still not acceptable.

This concludes my test to see if I could get a better DOF. I'm stumped! I'm sure I must be missing something. Maybe the correct lens for this type of photography?

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March 10, 2009

- Dennis Flanagan

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One issue is your short focal length lens. Do you have something longer? The longer focal length has a shallower depth of field.

Don't get to alarmed about the histogram being blown out. With as much white as you have in your scene, that is going to happen. Another thing, try placing your second light behind your subject pointing at our white background. In High Key photography, you want your background bright white. Try your main on low power and your background light on high. Position it so your modeling lights brightest spot is right behind your subject. You may need to find something to put between the model and background light to prevent spillover. I typically run my background light in high key one to two stops brighter than on my subject. It will also kill the wrinkles.

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March 10, 2009

Aimee C. Eisaman

I do have a 55-200mm lens that I could try. Unfortunately all my lights run off a single power pak and I can only control the settings for the whole thing. I cannot adjust lights individualy. I do have a third light for backdrops and yes it would work in this shot to blow out the background thus eliminating the wrinkles which would mean I wouldn't have to worry about DOF. Here's the problem. I don't put my kids up on a table so that I can put a light on the floor behind them.

It seems my issue has alot to do with my kids! LOL! I'm finding studio photography with my kids....not so fun! I do however enjoy using my lights to do still life shots.

I'll try with the longer lens.....

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March 11, 2009

Aimee C. Eisaman

Duh...I have a macro lens that would work best for this....it has been sitting in my bag all along. It's a Sigma EX 105mm 2.8. Gave it a shot even with 2 lights going. One thru a white umbrella and the other reflected. Got this shot at 250 (even though you can see some shutter shadow) and F8. Can still see the wrinkles in the background, but they are nice an even now. I think I found a starting point to figuring out what I can accomplish with what I have!

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March 11, 2009

- Gregory LaGrange

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For white and light colored backgrounds you need to start with a smooth surface, especially with that short of a distance.
Use an iron or get some seamless paper.

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March 12, 2009

Aimee C. Eisaman

Looks like I'm gonna have to just be happy with wrinkled! Since I have to drag all my stuff out of boxes to work with my studio stuff I don't think I'll be taking the hour or two it would take to iron a 10X20 backdrop. Paper would have been the way to go and in hindsight I should have gone that route. Maybe in the future! Thanks!

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March 12, 2009

- Dennis Flanagan

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Go to Walmart and buy a steamer. That's what I use to get the wrinkles out of my backdrops. It takes about 10 minutes after hanging it.

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March 12, 2009

Aimee C. Eisaman

wow.....what a fantastic idea! wonder how much they are?

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March 12, 2009

- Dennis Flanagan

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neighborhood of $30 to $50.

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March 12, 2009

Aimee C. Eisaman

Thanks so much for all your help Dennis.....without going thru all of this it would have never dawned on me to use my 105mm lens as a portrait lens. I took the lights down today and used it with natural light from the window and my cameras flash for fill and got great results for DOF and color. Starting to wonder if this studio light thing is for me. I like the look of natural light so much more, but then again it isn't always readily available and my lights for the most part are! :~)

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March 12, 2009

John H. Siskin

Hi Aimee,
Sorry I didn’t notice this thread earlier. Your shutter speed has nothing to do with exposure with strobes! The strobe has a duration of about 1/1000th of a second, which your shutter can’t control. However, if your shutter is in front of the sensor when the strobe goes off you get a partially black picture. The highest shutter speed you can use with strobes is called your sync speed; it is different for different camera models. Check your instructions. You can use a longer speed if you want to add light from other sources, such as daylight.
If you want to reduce the light from your strobe further than you can with the controls on the strobes, you can use neutral density filters or use metal window screen over the strobes. Most monolights will reduce power output to 1/32nd power, which gives you more control. You might also want to check out this article on making light panels: www.betterphoto.com/article.php?id=156.
Thanks, John