How to take a clear long exposure picture? (Can't find the right balance)

[ClarkKent18]

I am using a Nikon D5100 DSLR with an 18-55mm with an f 3.5-5.6 AF-S lens on a tripod. I am trying to take a long exposure picture of me using sign language (ASL) signing a little statement; it’s an assignment for my class. Every time I can clearly see the first sign, but the rest is very blurred (very ghost like and can’t see anything) or very bright. I am in manual mode and have been playing with the aperture, ISO, and shutter speed (3-6 seconds) and I cannot get the shot I looking for.

I am shooting outside in clear light and I cannot find the right balance between the aperture, ISO, or shutter speed. The background is an off white color and I am wearing a black t-shirt. This is the first time that I am using a long exposure and I don’t know what I am doing, I am not going to lie.

What would you recommend for the aperture, ISO, shutter speed, or any other setting within the camera to get a clean and clear shot? I have been using 3-6 second exposure, should I make it longer and sign slower? Any feedback would help me out a lot since I am so lost.

Thank you for your time

 

[fokker]

Basically it's not going to be possible to get a single long exposure shot with the signs being clear or legible.
The only way I could think of doing this would be to take a long exposure (say 30 seconds) of you in complete darkness, but every time you do a sign, somehow trigger a remote flash to light you up for a brief splitsecond. That way only the 'flashed' exposures will show up. If you don't have an external flash unit, try borrowing one or find an old manual one. Most units have a button you can press to fire them, and you could just have a friend press the button for you when you say.

 

[Kerbouchard]

Basically it's not going to be possible to get a single long exposure shot with the signs being clear or legible.
The only way I could think of doing this would be to take a long exposure (say 30 seconds) of you in complete darkness, but every time you do a sign, somehow trigger a remote flash to light you up for a brief splitsecond. That way only the 'flashed' exposures will show up. If you don't have an external flash unit, try borrowing one or find an old manual one. Most units have a button you can press to fire them, and you could just have a friend press the button for you when you say.

I had to check to see if this was my post. I had just typed basically the exact same thing, but canceled the reply.

Couldn't figure out a solution to the ghosting caused by the head and shoulders being in different locations for each flash.

About the only thing my reply would have added that yours didn't was that it might be possible to do without a flash if he has a friend turn the light switch on and off in between signs.

The other option would be shooting multiple different shots and then using photoshop to merge them into one.

 

[ClarkKent18]

The only way I could think of doing this would be to take a long exposure (say 30 seconds) of you in complete darkness

I did not think about shooting at night. With that suggestion in mind, what would be a good starting point for my aperture or ISO. I am not looking for a shot that you can read each and every sign, but have an idea what I am signing or have what I am signing is blurred and not ghost like (the first sign is very clear and as I continue, it fades out, not what I am looking for). I am trying to have all my signs blurred all together. What I am trying to show is in ASL, some one who is deaf signs really fast. To any outsider, it looks all blurred, until you know the language and understand the culture.

 

[Kerbouchard]

Shooting it in the dark makes your settings almost not matter. Shutter speed will not be a factor, so it would probably be set at whatever your longest shutter speed is. ISO could be set at ISO 200. Aperture around f/8 or so. The exposure would be controlled with the flash, but again, you would run into exposure issues where each part that is in the same location would get brighter with each flash.

Just thought of a possible solution, and it involves painting with light and an assistant.

Basically, you would need a flashlight and a dark room. You would use a long exposure, perhaps around 10 seconds or so. You would then trigger the camera when the lights are on, have a friend turn the lights off after your first sign that is clear, then have somebody point a flashlight just at your hands. Would take some trial and error, but should be possible.

 

[ClarkKent18]

Just thought of a possible solution, and it involves painting with light and an assistant.

I like this idea and I will be playing with it. I have a few ideas in mind with this idea you have. Thank you. Please keep the feedback coming.

 

[KmH]

Kerbouchard is on the right track in that you have to use strobed light, or light painting.

Your problem is that the ambient light is being recorded as you move, and since the shutter is open, any movement you make is blurred.

Shutter speed is what stops motion when only ambient light is used to photograph a scene.

By using strobed light (flash) you can use the short duration of the flash to stop motion. The new problem becomes having several flashes of light in a long exposure will overexpose you, unless you move so the flashes of you do not overlap. (same for light painting)

However, look at page 78 of your D5100 user's manual - Multiple Exposures for a possible simpler solution if your "little statement" is short enough. You will still have to change position so each shot of you making a different sign will not overlap and be overexposed when the multiple exposures are all combined.

Otherwise, you will need to just shoot it as a video, which is shooting at least 25 still frames every second.

 

[Helen B]

Would a B&W image work? It would be helpful to increase the brightness of your fingers relative to the background, and that is easier in B&W than it is in colour.

How many signs in the phrase? If there are about four it will be easier than if there are more. Does the number of signs really matter to the meaning of the image?

I don't know the colour of your skin, but unless you have unusually light skin the difference in reflectivity between your skin and your black t-shirt is likely to be no more than two stops.

Suppose you had a phrase of four signs, and an exposure of 8 seconds. This means that it might be possible to hold each sign for just less than two seconds, with very fast transitions (don't sign at normal speed and rhythm). This means that the changing parts of the image get a quarter of the exposure time that your shirt does (except for those changing parts which are in the same place as another changing part). So, they are two stops brighter than your shirt, but get two stops less exposure time, therefore they are about the same brightness. However, for 6 seconds of the exposure the black shirt is illuminating the same area of the sensor that is briefly occupied by the moving part. Therefore the changing part has a chance of registering as almost a stop brighter than the shirt, but increasing the brightness difference between the changing parts and the black shirt would help. You can do this with makeup (your fingers don't have to be completely white), or with red filtration on the camera or the light (or use the red channel only) if you are not dark-skinned. You would set the ISO to the lowest your camera can manage (to get maximum dynamic range), set the aperture to something like f/8 (not critical) and light accordingly.

Good luck,
Helen

 

[Forkie]

I'm not even sure I understand what you're trying to do! Are you trying to show key parts of each sign? Obviously if you have the shutter open throughout a sign your hands will always be blurred.

I'd have thought that the best solution would be to take a shot of each sign/part of the sign and stack the images to make a composite (if I've understood what you're trying to achieve).

 

[Jesse11]

good ideas,i also will do it follow them.

 

[bazooka]

Helen beat me to it! No flash needed. You'll have a pleasant blur that indicates fast motion, but each sign will be well exposed and identifiable.

 

[ClarkKent18]

I like your idea Helen, I will be trying that tonight. But here are a few that I was able to take that turned out better then once I started

If you did not read my statement above, I am trying to show what ASL looks like from an out siders point of view. Some one that
not understand the language or the culture, it all likes like a blur until you take the time and learn.

Please feel free to C&C

[TABLE="class: kmsg, width: 618"]
[TR]
[TD="class: kmessage-left"]Nikon D5100
18-55mm lens at 24mm
f 20
ISO 250
4 seconds
Camera was on a tripod as high as I could get it with a spot light right under it

[/TD]
[/TR]
[/TABLE]

 

[Helen B]

They look pretty good. Was the light fairly close? Using light falloff is a good way of raising the brightness of the hands relative to the shirt.

 

[ClarkKent18]

Yes the light was right under the camera and I was about 3 feet away. I tried having the light fair away but the shadow of the tripod was killing it. I had the tripod as high as I could get it on top of my desk, being 6'3 does not help.

Now that you can kinda see what I have in my, please keep the ideas coming!!