Experimenting with Flash

Robin Usagani · Mar 1, 2012

You cannot agree with me AT ALL you said. Did I ever say anything about front facing bounce? I agree with Niel Van Niekerk and I have nothing but preached what he said to everyone here. For you to say you cannot agree with me AT ALL sounds bogus to me. Please dont pull the seniority card on me Derrel... it is lame telling me you have been doing it since I was not even born.

Derrel said:
I just simply can NOT agree with this, AT ALL. First off, when one bounces a flash indoors using standard front-facing bounce methods, there's a very great tendency for the light to come raining almost straight down, which is what creates the lifeless and dull look in the dog pics. Using "something", "anything", to get just a little bit of flash going right at the subject to create a catchlight is often better than straight,plain, forward-facing bounce flash. Try a bent business car, or a plastic spoon, taped or rubber-banded to the flash, so that a little bit of the flash beam hits the card or spoon. This is a method for CLOSE-range shooting, as you were doing with the dog...this is a 1980's PJ trick--not for long throws, but for CLOSE-range, indoor bounce flash shot with the flash-in-the-hotshoe method. Like the two shots of the dog.

As far as getting "good light metering" with TTL bounce flash...uh...that might be one of the single biggest weaknesses Canon cameras have had for the past decade. STRAIGHT-AHEAD e-TTL-II flash is decent, although nothing to write home about. Note the qualifier-e-TTL Version II. Color-blind flash and color-blind ambient light metering is a recipe for bad through the lens flash regulation. Nikon has been ahead on color-aware flash and color-=aware ambient metering + distance for a long time. Some of the differing opinions on bounce flash and flash as a whole come out of the tremendously different ways that Canon and Nikon have developed their flash metering and flash-regulation concepts. before e-TTL-II was developed, Canon had a HUGE problem with TTL flash being overly-sensitive to the specific AF spot that was active. The shiny d-slr sensor and AA filter makes the pre-flash rather so-so in terms of reliablilty and repeatability...film simply worked "better".

In many ways, the old AUTO-Thyristor flash metering is better than e-TTl, E-TTL II, d-TTL, or Nikon i-TTL.. It always "depends".

One of the single BIGGEST problems you will run in to when bouncing a single speedlight is that the flash will NOT be powerful enough to expose the shot well enough if you are using the lower ISO ranges with "normal flash units". Using HIGH-ISO settings and bouncing the fl;ash is a technique that Dennis Reggie (sp?) is sort of famous for. As Keith stated in post 10, it can be difficult to separate the BS from the good stuff; his link to Neil's web site is a good,good link that's free of the BS. You can try adding "+" exposure compensation on the flash unit--but if the room is big, the aperture small, or the ISO low, or any combo, then all the "+_" compensation in the world will not give any more exposure if the flash is "topped out"...

Bounce flash can look fantastic, very good, okay, or bad; it largely depends on the skill of the photographer and how he/she uses the equipment and the location.

CowgirlMama · Mar 3, 2012

Ok, rather than starting a new thread, I'm just going to add tonight's experiments here.

My subject was a little less cooperative, but I still got to play around with the flash a bit. I tried a bunch of different ways, but I'm just going to post two. They were both ISO 100, shutter 1/200 and something like F4. I can't remember exactly and I have an unhappy toddler clinging to me. Neither has anything but very basic PP done (sharpening, etc. before converting to jpeg).

This one, I bounced off the ceiling between us, with some white cardstock rubber banded on. It was about 1/2 inch past the top of the flash. I didn't get any catchlight in his eyes, even with the cardstock.

The lighting seems flat to me.

This one, the light is bounced off his off-white highchair about 45 degrees to the right. I need to get real reflectors. (My birthday is coming up and my parents are getting me photography stuff, hopefully including a reflector.

) In spite of being a highchair and not a reflector, it did bounce the light pretty well. I liked this one better because it gives shadows and showed more details.

I took lots of other shots and will be doing more experimenting tomorrow. I'll probably start a new thread for tomorrow's adventure, though.

Thoughts?

ETA: I know there's stuff behind him. I was just focusing on lighting for today and taking what I could get.

Robin Usagani · Mar 4, 2012

You almost never want to bounce on the ceiling between you and the subject. You want to bounce it to the back. I know it sounds silly because if you bounce it to the back doesnt seem to be bouncing to your subject but it does. The only time you want to bounce it between you and subject is when the subject is far away from you. So try again bounce it to the ceiling behind you (flashead about 45 degree facing back) and try to shoot the flash to the side a little.

pgriz · Mar 4, 2012

Based on KmHs recommendation to me last year (Amazon.com: Light Science and Magic, Fourth Edition: An Introduction to Photographic Lighting (9780240812250): Fil Hunter, Paul Fuqua, Steven Biver: Books), I got the book and it has helped me tremendously in understanding the why behind many of the recommendations we get for lighting. Im still working my way through it, although Ive read it from cover to cover several times, and am now practicing the various principles discussed.

The key idea is that the quality of the light is determined by its size (an distance from the subject). The smaller the source, the harsher the shadows and more glaring are the highlights. That is probably a good description of direct, on-camera flash. By contrast a large softbox will give you soft, almost wrap-around lighting.

The second effect is the inverse square law that describes the intensity of light with distance: the intensity diminishes as a reciprocal of the square of the distance. So, if you have 100% of the light at 1 ft., it falls off to ¼ the intensity at 2 ft., 1/16[SUP]th[/SUP] the intensity at 4ft., and so on. If your flash properly exposed something at 2 feet, then that what was at 4 ft. is two stops underexposed. Kundalini posted a clip from Adorama that explored the inverse square law: [video=youtube;f5BIvSBjvLg]http://www.youtube.com/watch?feature=player_embedded&v=f5BIvSBjvLg"]http://www.youtube.com/watch?feature=player_embedded&v=f5BIvSBjvLg[/video]

The take away lesson from that is that if you want dramatic shadows, you bring the light source close to your subject, if you DONT want that, you need to put the light source further away.

These two ideas are behind why bounce works (well, kinda, shorta, etc.). By bouncing the light , you are replacing a small light source (the flash) with a much larger light source (the surface illuminated by the flash, which now becomes the source for the subject). The second effect comes into play in that the bounced surface is further away from the subject than was your flash, and the light fall-off (due to distance) is less so the difference in brightness between your subject and the nearly surroundings is also less.

However, theres no free lunch. The inverse square law was not repealed. By bouncing the light off the back wall, for instance, the amount of light emitted by the flash is now spread out around the whole room, and therefore the amount of light reaching the subject is much less. You end up using rather large (ie, wide-open) apertures to get enough light to the sensor to get a good exposure (or you boost the ISO, or you get a much stronger flash).

The next thing to address, is the direction of the light source. If you bounce the light directly on the ceiling above, you have a largish light source shining directly down on your subject. Chances are, the eyes will be in shadow (the famous raccoon eyes). If you bounce the light directly behind you (assuming there is a white wall there), then you will get relatively even but flat lighting. If you bounce the light on a side wall, then you will have a light source what is large but lights your subject only from that side.

Another way to deal with this is to use a reflector instead of a wall. The reflector could be a white bedsheet, or a large white cardboard, etc. Youd have to think about the direction of light you would want to illuminate your subject, then arrange to position yourself, the flash, and the subject so that the flash bouncing off the reflector would give you the end result. Yeah, thats a lot of contortion. Which is why off-camera flash is popular with photographers. The flash unit is set up to do its lighting job, and the camera is moved around to take the picture from the right angle. But now you need a way for the camera to trigger the flash, and to figure out the correct exposure OK, were probably not there yet.

Back to bounced flash. Find an unobstructed corner that is painted white. For the purposes of this thought exercise, locate it on your right about 4-6 feet away from you, and about 90 degrees to your right (0 degrees is directly in front of you, 90 degrees is on your right, 180 degrees is behind you, and so on). Position your subject on something comfortable in front of you. Aim your flash head (of your on-camera flash) towards the corner. Focus and shoot. Since you lit the corner, the light should be partly on the side wall and partly on the wall behind you, and should give you a large soft light, but still with shadows. Move around until you find a combination of distance from the corner, and angle of flash that gives you the results you want.

CowgirlMama · Mar 4, 2012

Schwettylens said:
You almost never want to bounce on the ceiling between you and the subject. You want to bounce it to the back. I know it sounds silly because if you bounce it to the back doesnt seem to be bouncing to your subject but it does. The only time you want to bounce it between you and subject is when the subject is far away from you. So try again bounce it to the ceiling behind you (flashead about 45 degree facing back) and try to shoot the flash to the side a little.

This one won't angle back.

It only goes as far as straight up.