bkyser Loc: Fly over country in Indiana

OK, I admit, I'm stuck in the 70's. I just don't trust, and am not used to TTL, and the few times I tried, it, wasn't really satisfied with the results. Maybe Jerry, Ed, or someone else can straighten me out. I thought I understood it, but a guy in the park last week was either completely wrong, or I have been.

TTL (iTTL) stands for Through the lens, so.... I was at a park that I will be shooting a wedding at soon. It is our community's "rose gardens" Just checking the progress, as they dig up ALL the plants, and keep them in greenhouses, then replant every year. A gentleman was there taking pictures with an impressive Canon set up with L lenses, using off camera flash, etc. So, me being me, who loves to talk, network and just meet people, started a conversation.

We got around to the fact that he shot with his nice DSLR, in P mode...fine... and used TTL metering. He had a small softbox, and had the flash body turned around with the head towards the back of the box (check) but the infrared panel was facing the subject. He said that the infrared plastic thingy was what metered the pre-flash, and sent the info to the camera body. Am I wrong, or is that NOT how it all works? I know nice equipment, doesn't mean anything.

At first, I figured, yeah, he doesn't know what he's talking about, but I just use manual flash, and when I tried TTL, I ended up with over and under exposed images (why I don't use/trust it) So, have I been wrong by not pointing the infrared port towards the subjects? (often covered by diffuser anyway), or is this guy just full of it?

On a side note, I do use Yongnuo 622 triggering with TTL capabilities. I have 7 flashes (2 are manual only), so I could try the set up Jerry mentioned in his last post, but I'm still very uncomfortable with TTL, and trusting it. I know practice makes perfect, but I can't tell you how many times, I set something up at home (like the event printer), then when I get to the venue, SOMETHING always stops working the way it worked when I tested it.

Rick36203 Loc: Northeast Alabama

I'm afraid he was mistaken.

In TTL, the flash fires twice for each exposure... as I'm sure you know. The 'camera' (not the flash) evaluates the pre-flash exposure of your composed scene based on it's metering setting, and sends power corrections to the flash for the 2nd firing.

The flash IR sensor may need to see the camera's command flash if being controlled optically, but that is for communication only. The pre-flash exposure is what is evaluated. And, the evaluation is done by the camera, not by any flash.

http://www.youtube.com/watch?v=VnU-QHIyp5o

http://www.youtube.com/watch?v=MF0V19TBs60

Beercat Loc: Central Coast of California

He was incorrect ......

The camera meters the pre-flash. The only exception to this is if you have a flash programmed for external metering sensor.

On the front of a 600EX-RT there is a AF-assist beam emitter and a external metering sensor, plus a optical sensor but for the way he was shooting in P mode and ETTL they don't come into play.

He may have a flash or more programmed ETTL and the softbox flash programmed as an external metering sensor, in which case the unit would need to be facing the subject while he had the head pointed into the softbox. If this is the case there could of been some confusion.

bkyser Loc: Fly over country in Indiana

I hadn't heard of using a flash programmed as an external metering sensor. Is that a Canon thing, or just another bit of technology that I've let slip through my grasp of understanding.

Going by your setup in the other post, and the Zinser method, I'm trying to get a handle on the TTL thing, and this guy completely threw a monkey wrench in what I thought I was starting to grasp.

I think it's the studio lights, and using a hand held meter instead of relying on the camera's meter and evaluative metering that is why I still think it is easier to go full manual, but it is a lot slower. For me, thinking about exposure compensation and all that jazz seems more difficult than taking a meter reading for a certain situation, and then just shooting away until the lighting changes. (changing a little doesn't effect me too much, since I also shoot in raw. However, the Zinser stuff (I got the book a long time ago, and read it a couple of times) sure makes it look and sound easy, and I do like not having to worry if I have someone in the right place holding the lights stand.

To be honest, I often forget to look at the in camera meter, as I just trust my hand held meter. Trying to get away from that, but old habits die hard.

Beercat Loc: Central Coast of California

don't know if nikon has it but the canon 600 does have it as an option

jaysnave Loc: Central Ohio

Bob, I am right there with you. I will join you in the stupid (uninformed) club regarding TTL. I tried it early on and like you I liked the results some of the time and disliked them some of the time. Maybe I will give it a go again. Jerry & others seem to have it mastered. I am more comfortable with everything manual because it allows me to add as much light as I want. My personal preference is around 60% ambient and 40% flash just to enhance skin tones. I just used my rapid box for an engagement shoot. It operates by bouncing light off a shining disc thingy sort of like a beauty dish. I like custom adding light based on power to the flash and closeness to the subject(s). TTL may be an option in a dark reception where ambient just doesn't cut it. We will see.

bkyser Loc: Fly over country in Indiana

I had an engagement session Sunday, I hope to post a few as examples.

The ones that used TTL and A mode, vs full manual. the TTL ones still all look washed out to me. I think there is more to know than "trust the flash"

Beercat Loc: Central Coast of California

Are you using Eval mode for sampling? You need to have both the speed light programmed for Eval mode as well as the exposure metering set to Eval mode.

Tim Stapp Loc: Mid Mitten

I seem to recall reading someplace (Neil van Niekerk?) about setting -1.5 stop flash compensation when shooting iTTL on Nikon.

Tim Stapp Loc: Mid Mitten

I may have been wrong (big surprise). Here is a link that may help: http://neilvn.com/tangents/flash-photography-techniques/flash-exposure-compensation/

Beercat Loc: Central Coast of California

I would agree on direct "fill" from on-camera flash the average is typically -1.5 FEC

Key light set to neutral to start. This is for reception type lighting on stands. I place my key and kicker at 13 feet, both set to neutral to start and the fill set to -1.3 FEC .... that is my starting point, then as all should do you chimp and make any final adjustments but it will be close ...

Not unusual for me to be +0.6 on the key/kicker. I also wet my zoom range on the key/kicker to 80mm to help funnel the power to the main part of the dance floor. Typically my stands are 25 - 40 feet from the edge of the dance floor thus 80mm is about right. I've had times where the stand was 50 feet away from the dance floor so I set the zoom to 105mm.

There is no right or wrong way to set reception flash. I've gone the route I have to keep it as simple as possible with very little variation in lighting, it stays pretty vanilla. Would rather get solid good exposures than to go to artsy. I started shooting in TV mode during the reception time when the the flash units are used. I prefer to have solid stop frame action. No need to drag the shutter if you have both key and kicker lights as the background will be lite just fine. Trying to stay in the fail safe mode as much as possible.

jaysnave Loc: Central Ohio

Thanks for the resource links guys. I need to read up. Like Bob, I have been trying to use more automatic modes. I was doing an event shoot yesterday where I was using A priority with speed light on TTL. I snapped two pics within seconds of each other. The first looked good, the second was way overexposed. It drives me crazy when I don't know what is going on in that Nikon brain. My brain immediately went back to manual until I figure it out. Not sure if I ever will.

Tim Stapp Loc: Mid Mitten

One thing that I do is utilize spot metering, usually (always) the face.

Beercat Loc: Central Coast of California

I do when no flash but once the flash is on I go Eval but as they say there are many different ways to get to the same destination :)

jaysnave Loc: Central Ohio

OK Jerry, that makes sense. I was on spot metering and the spot could have moved to a darker area on the second shot. With Nikon, there is spot, center weighted, and matrix metering. I will try center or matrix while using TTL flash.