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Old January 5th, 2008, 04:28 AM   #1
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light match from video to still photo

Im wondering if someone here has insights and experience in lighting both for video and photography at the same time.

After purchasing a lighting kit, which should be usable for both video and still photos (constant light as opposed to strobes) I realized that when the light conditions are setup perfectly for a video shoot, the same light condition is way to dark, to use with a photo camera.

So what Im asking is, would it be possible to setup you scene to be illuminated perfectly for both, where the still image and the video footage, has the same look, illumination and mood.

I can emagine the first reply to this would be... Get more light!
But how much more, and how do I calibrate my cameras to match up?

I will get a lightmeter in a few days which I suppose will be nessessary for this. But equipment alone is not enough if you dont know how to use it.

I have a Canon XL2 with the stock 20x lens and a Canon EOS 400D (Rebel Xti) with a 28-135 IS f3,5-5,6 lens. And Im getting the Sekonic L-758Cine light meter.

Is there any calculation method or diagram available that could tell, that if I forinstance use one specific setting on my Xl2, what the corresponding setting on the 400D would be?

Last edited by Nik Skjoth; January 5th, 2008 at 05:34 AM.
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Old January 5th, 2008, 06:11 AM   #2
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Production stills photographers do this all the time. Part of your problem is that your stills lens at f3.5 -5.6 is rather slow compared to the apertures commonly used to shoot interiors on video & film.

You'll have test your XL2 to find out it's ASA and then rate your stills cameras ASA to match the exposure (having worked out the shutter speed you wish to use - I wouldn't go too high and you may actually wish to use a slower shutter speed given that video cameras are usually in the 1/48 to 1/60th range.).
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Old January 5th, 2008, 06:41 AM   #3
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Thanks for the reply Brian.

My tests so far have shown that in the scene where my XL2 is set to:

25p, Shutter at 1/50, aperture at f2 I get the perfect image that Im aiming for, with the light at hand.

Now if I want to mimic that with my 400D I would have to go as far as 1/15 shutter speed, with 3,5 aperture and iso 400

Now. Could this observation be used somehow so that I can calculate how much more light I need, to have a more still photography friendly lighting enviroment.
Lets say that I want approx 1/150 shutter speed, f8 aperture and ISO 200 at the most on my 400D. Thats 3 distinct changes, which to me seem like a dificult task to calculate as to how much more lumen would be required..

If I only had to change the shutter speed from 1/15 to 1/150, it would mean that I had to multiply the lumen ten fold.. (is that right?)
Then I would simply put a ND filter on the XL2 to compensate.

Another problem is that even if I set both cameras with the same settings: 1/50 shutter, f3,5 aperture. They behave somewhat differently. I suppose its due to the sensor size and the pixels per inch that make the XL2 more light sensitive.

To be hones Im more experienced with video than I am with still photography, so Im not sure if it means a lot to the picture what shutter speed Im using. Since I dont need motion blur in a still image, the shutter speed would be irrelevant, and still give me the overall same image compared to the video footage at 1/50 shutter speed?

Last edited by Nik Skjoth; January 5th, 2008 at 08:13 AM.
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Old January 5th, 2008, 08:30 AM   #4
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Ok so now I found out that the iso of the XL2 is just under 200.

I used iso 400 on the 400D before. Thats why they seemed to behave different.
When setting the iso to 200, matching the shutter and aperture of both cams, I can now get an image that looks pretty close, and the light meter on both is centered.

So thats fixed, now I need to calculate how I get just enough light to have a nicelly lit scene.

I cranked the aperture on the XL2 down to f4,0 for being able to set the same f-stop on the 400D. I would still like to use a f2 on the XL2 tho, for a better DOF control and instead put on a ND filter.

now the question is, how many lumen do I need to multiply with in order to get a good lit picture on the 400D, with more managable settings.

Here is what I need to calculate:

Initial setting that give good picture illumination but dificult to shoot with:
Iso 400, f3,5 aperture, 1/15 shutter speed.

Target setting:
Iso 200, f8 aperture, 1/125 shutter speed.

Who can crack that?

Last edited by Nik Skjoth; January 5th, 2008 at 09:17 AM.
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Old January 5th, 2008, 09:28 AM   #5
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Quote:
Originally Posted by Nik Skjoth View Post

Target setting:
Iso 200, f8 aperture, 1/150 shutter speed.

Who can crack that?
Why do you need f8? The lighting levels are required for 1/150 are way above those you'd use on a feature film set since the days of the old slow colour stocks of the 1950s. In average rooms you'd be using 5000 watt tungsten lights direct without diffusion, so for soft lighting you'd be using much larger units.

Best get some fast prime lenses for the stills camera and use them at f2, rate the camera at 400 asa and try to get a shutter speed around the 1/100 mark or 200 ASA at 1/50th. The real world does kick in at some point.
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Old January 5th, 2008, 10:35 AM   #6
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That kinda makes sense...

I was thinking about f8 to compensate for the larger Cmos on the 400D (DOF wise), and I often hear that f8 is the standard in still photography. Plus thats where my linse has the best performance. But I guess a faster f stop can do. I can go as low as 5,6 to avoid changing aperture when zooming.

Also I changed my post from 1/150 to 1/125 since thee 400D dosent have a 1/150 shutter speed.

All those numbers are only a theoretical target. Maybe I dont need to go as high as 1/125. I just want to make sure I can stop the motion of the subject, even tho its slow action, and we will be shooting the stills handheld.

In any case, It's not like I absolutelly need 1/125, f8, iso200, but I would really want to know how one would calculate for it...

Dont give me the fish, teach me how to catch one instead :)
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Old January 5th, 2008, 11:31 AM   #7
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Check out:

http://en.wikipedia.org/wiki/Light_m...sure_equations

If you're using an exposure meter for setting your exposure, you're better using an incident meter or take your reflected readings of a 18% gray card, otherwise your exposures will in inconsistent.
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Old January 5th, 2008, 03:12 PM   #8
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Here is a link to a set still on flickr:
http://www.flickr.com/photo_exif.gne?id=132274446
http://www.flickr.com/photo_exif.gne...xt=photostream

Here is the main page. On the right, down toward the bottom, there is a link for each picture that says "More Properties." Use this to see details about lens, speed, etc. Top right you can go to other pictures in the series:
http://www.flickr.com/photos/christi...n/photostream/

These pix are all shot at f/2.8 at about 1/60 or 1/100. If you go through flickr you will find that interior pictures shot with a higher f-stop will many times have very, very long shutter speeds (up to a few seconds, even).

It is necessary to find a nice balance between ASA, shutter speed, and f-stop for your particular situation.

It would not be a bad idea to get a quality large f-stop lens if you are shooting in this situation a lot.

Also, look at the program Noise Ninja. It is incredible at removing noise on pictures shot at a higher ASA. With Noise Ninja and your camera you should be able to shoot at at least ASA 800. Here is a link to Noise Ninja:
http://www.picturecode.com/

I think it makes most sense to light for your video. Then experiment with camera settings to get the best shots.

If some of this is new to you, try this. Borrow a good point-and-shoot camera that has a lens about the same f-stop as yours. Takes some pictures with it on auto. Look at the specs on the pictures and see what the ASA, f-stop and shutter speed. These are the settings considered optimal by this camera for your setup. (Remember, the goal of these cameras is to make pictures look as good as possible, nothing else.) Use these settings as a hint at what you can do to make your pictures right. Chances are the auto setting will be using a slow shutter speed. Also, may be suggesting flash (which would indicate to you a larger aperture, for example.).

Make some tests using different types of settings and see what works best. You might consider one or two fixed focal length lenses (prime lenses) if your pictures are always in the same range. To figure out what might work, set your zoom to a focal length, don't move it, and see if you can take all the pictures you need. Often you can get a better lens with a wider aperture for a less expensive price in a fixed focal length (prime).

Here is a great and unbiased site for lens information and evaluations for most lenses available for your camera:
http://www.photozone.de/8Reviews/index.html
Put the specific lens into the search box. Read a couple of the reviews to understand what the site offers. Here is the review of the lens I think you have:
http://www.photozone.de/8Reviews/len...6_is/index.htm

Last edited by Jack Walker; January 5th, 2008 at 11:23 PM.
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Old January 5th, 2008, 04:45 PM   #9
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If you have an SLR digital still camera, get a fast prime lens, like a 35mm, f1.8-f2 and you would be in better shape than using the slow zoom lenses these cameras usually have. You can get a 50 mm f1.8 Canon lens really cheap and it's pretty good. Of course on the 2/3" chip DSLRs that would be about 80mm equivalent.
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Old January 5th, 2008, 05:15 PM   #10
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Thanks for all the replies... So this kinda confirms my fear...

You can't really setup a perfect lighing condition for Video and Still photo at the same time...

Yes a faster lens would solve some of the problem, but Im afraid that the DOF would become to narrow. Besides. A prime lens is out of the question... If we had the time to change lenses on the set, it would be easier just to pause the video shoot, and ad strobes in the studio instead.
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Old January 5th, 2008, 11:42 PM   #11
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Then your options are simple.

1. Buy a zoom lens with wider aperture. (I use a pentax camera and just bought their new F2.8 digital wide angle zoom for a similar purpose.)

2. Use a tripod and slower shutter speed.

3. Up your ASA and use Noise Ninja software to take out the noise.

4. Set up some strobes with Gary Fong (or similar) diffusers]

5. Shoot RAW and slightly underexpose, then bring up the exposure in software.

What are the pictures for? Are you taking pictures at the same time you are taping? What is the scope of the pictures? (full set, full on actors, etc.) Answers to these will affect your solution. (If you're using an SLR I assume you are not shooting stills will you are recording sound. Thus, you could set up some strobes as suggested above.)

Bottom line, you have given limitations and you have to come up with the pictures. Put the pieces together the best way they fit withing the time and budget restraints.

Last edited by Jack Walker; January 6th, 2008 at 01:57 AM.
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Old January 6th, 2008, 01:31 AM   #12
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One other thought, it's very difficult to set up good lighting for two different video shots at the same time. Often times when two and three cameras are used, the lighting suffers or it is of such a nature that the poorer lighting works for the shots.

The more I think about it, a couple of portable slave strobes with diffusers mounting on the set above the camera line and triggered by the camera would give you even and instant lighting.
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Old January 6th, 2008, 09:34 AM   #13
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Thanks Jack...

The still images will be taken at the same time as the video recording, to photograph the actors while they are acting. The image quality is of almost as great importance as the video footage. And I've been told that slow shutterspeeds, and to fast aperture will make it dificult to get the right image, where the action is stopped, and all the actors are in focus. (upping the ISO to 800, seems so far to be the only option)

But if we do it in reverse...What would happend to the video image, if we flood the set with sufficient continuous light for still images, and instead tweak the video camera with ND filters and possibly faster shutter speeds to compensate? Would it look like as if the sun was knocking on the window? Can you even flood a whole set of approx 30 square meters with enough light?

I know that most photographers are married to strobes and flashes.. But latelly I read about many continuous light options that will effectivly do the same job. And some of them even advertize that you can use it for both stills and video.
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