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Through-the-lens metering (TTL) is a feature in many modern cameras that allows the user to measure light levels through the lens that will capture the picture.

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2
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1answer
36 views

Best approach to handle flash with my film camera?

Although I have been photographing for 3 years now, there are still areas I am fairly new to. I really love film photography, but I also like to use flashes for portraits and such. Of course with my ...
2
votes
3answers
228 views

If TTL only preflashes once, how does it get correct exposure immediately after?

If I understood TTL correctly, say you are in M mode with a camera and you have intentionally underexposed. The flash in TTL mode theoretically would try to add enough light to correctly expose the ...
0
votes
2answers
199 views

Inconsistent TTL results when flash used off-camera (YN565 EX II)

I've got a Yongnuo 565 EX II that meters flawlessly when attached to the hotshoe of my 60D, but is very inconsistent when used off camera and slaved to the built in flash unit. It frequently doesn't ...
8
votes
5answers
450 views

How does TTL flash work when there are multiple flashes?

I've been watching a lot of deconstructing videos on how the light is setup. Often times there are 2-3 flashes at the studio. The photographer will say that they are all set to TTL. But how does that ...
1
vote
1answer
193 views

E-TTL underexposure with flash zoomed in and shot through a modifier?

I think I have a Canon E-TTL issue with a specific camera body/lens combination when the flash is fired through a modifier (umbrella or softbox). When I use my EF-S 17-55 f/2.8 lens on my 60D body, ...
2
votes
0answers
105 views

Promaster Flash Module TTL on a Modern Canon DSLR

I have an old Promaster FTD 5600 flash. These flashes have an interchangeable module that allows it to work with different manufacturers' TTL systems. Right now the flash has a Nikon module; it does ...
2
votes
2answers
132 views

Why is flash TTL metering independent from ambient light metering? [duplicate]

In other words, why is ambient exposure metering independent from TTL metering? Let's say Im taking a picture in a room that has a window and some daylight is getting in,and Im shutting in P (program ...
4
votes
1answer
455 views

Pentax K-30 + Metz 52 AF 1 as off-camera slave

I recently bought external flash Metz 52 AF 1 and I have Pentax K-30 camera. Wireless mode works fine, however i expected it will be possible to use ONLY Metz flash without built-in pentax flash - ...
2
votes
2answers
129 views

Does auto mode of flash metering have any advantage over TTL?

Does auto mode of flash metering have any advantage over TTL? One advantage that I can think of is the absence of a pre-flash in the auto metering, which can make some people blink. (But I rarely use ...
1
vote
4answers
2k views

Does Canon 450D (Rebel XSi) have TTL ratio control over the menu?

There is "External flash control" section in the camera's menu. However it is not accessible if you have no external TTL flash on hand. How can I find out is there ability to change the output power ...
2
votes
3answers
601 views

How do I determine whether flash fired or not?

For example, I use a regular cropped DSLR (like Canon 400D (Rebel XTi)) and I use an external ON-camera flash (mounted on the camera's shoe). How do I determine by looking over the description within ...
2
votes
2answers
140 views

Does the Canon 600EX use face detection for improved ETTL?

I read that the canon 600ex rt has some face detect eTTL magic. Has anyone found this to provide real improvements? I'm shopping for a second flash and want to know if this is worth taking into ...
8
votes
2answers
471 views

Why is there still a flash before my exposure when using second curtain sync?

When I used second curtain sync on my Canon DSLR, I noticed that the camera flashes twice: once when the shutter opens and the other time when the shutter is about to close. (I noticed that because I ...
3
votes
5answers
322 views

Does TTL by definition overexpose your subject? [duplicate]

So I'm only beginning to learn TTL but from what I understand the preflash determines how much flash power to use. But the camera already exposes everything correctly for the entire scene (assuming ...
3
votes
1answer
213 views

What should I pay attention to when buying a second hand flash?

I am planning on buying a second hand ETTL flash for my Canon 550D. What are things I should pay close attention to when buying a second hand flash? For example: is there a parameter, comparable to ...
4
votes
2answers
146 views

Does a flash's TTL automatically adjust as I change its location?

I just bought a radio trigger for my flash. I was just wondering if I understood TTL correctly, as I move the flash around and changes the distance does TTL automatically try to compensate (assuming ...
5
votes
5answers
324 views

What are the most important features to look for in a low budget hotshoe flash and why?

When trying to get started with flash photography, there are a lot of new options, features and techniques that a photographer gets thrown in to. When starting on a budget, what features will give a ...
4
votes
3answers
983 views

How do TTL flash metering systems calculate how much power is needed?

Does anyone know how TTL calculates the amount of power to put in after the preflash is done? I understand that the value is somewhat brand specific, but what is the general logic? Because if you ...
3
votes
1answer
466 views

Why is my Metz 58 AF-2 using long shutter values when my Canon 60D is in Av mode?

About one year ago I bought a Metz 58 AF-2 for my Canon 60D. Because of a lack of free time to experiment with automatic functions, I have used it only in manual mode with other manual flashes, ...
1
vote
2answers
161 views

How do you meter for the effects of a TTL flash

I'm experimenting with a shoe mounted flash at the moment. It's a TTL flash and yet the metering doesn't seem to account for the fact the flash will fire, making judging the correct exposure ...
1
vote
5answers
313 views

What exactly does TTL flash sets its power to?

I understand that TTL flash means the flash will preflash and try to calculate the right exposure for that particular scene. That part makes sense, but what exactly is the "right exposure"? Does it ...
3
votes
1answer
254 views

Does the Canon DS6041 support TTL flash?

I've got that Canon model, and I'm using it with a Promaster 7500DX flash. The flash appears to support TTL light metering, but I can't find any way to make the camera recognize this. Consequently, ...
3
votes
3answers
350 views

How does TTL flash metering works in film cameras?

Unlike digital cameras, there are no pre-flashes in film cameras that do off the film metering. In absence of pre-flashes I want to know how camera can determine accurate flash power when flash is ...
4
votes
2answers
263 views

Why is ETTL necessary?

As I understand, the required flash power for correct exposure is determined by aperture, ISO and subject distance. It shouldn't matter whether a human subject is dressed in black or white -- the ...
6
votes
2answers
1k views

Pentax P-TTL: Why and when does underexposure occur and what can I do?

Pentax's P-TTL flash metering system tends to be unreliable and may underexpose at times. When and why does the system underexpose and what can I do? I want to know the situations that cause flash ...
6
votes
2answers
212 views

Can Nikon flashes display flash power used right after a shot was taken?

I'm trying to compare two camera bodies (Nikon D90, Nikon F100 (digital and film)) with respect to TTL flash power in different situation. I came to know that few Canon flashes can display the flash ...
2
votes
1answer
257 views

Will the YougNuo YN-565EX set as slave work as TTL?

I'm trying to figure out something for a project that's upcoming. I'd like two flashes on stage (maybe three) triggered by an ST-E2 on-camera from the back of the room and various places in-between. ...
1
vote
1answer
716 views

Manual or Automatic Speedlight?

I'm beginner photographer. I thought of buying Speedlight and found cheap Yongnuo 460 for about $35. But it is Manual (No TTL). Is it hard to use Manual flash without TTL ? Should I have to choose ...
8
votes
7answers
5k views

Advantages of TTL over manual mode when using speedlites

Yesterday a user on stackexchange asked me why do I prefer manual over TTL when working with speedlites. I use them mostly off-camera and I've developed a kind of a workflow where I do not walk back ...
2
votes
1answer
146 views

Why does FEL not work with flashes set in manual power mode?

I have a couple of 600EX-RTs and a Canon 5DMkIII. I am using group mode (or manual mode) with the flashes set on manual. Why does the FEL not work in manual mode?! It works in ETTL. It seems like ...
0
votes
2answers
902 views

Why does ETTL occasionally fail with my Canon Speedlite 580 EXII?

I have the Canon Speedlite 580EXII for 3-4 years now, and I have used it with a 450D and more recently with a 60D. With both bodies, there was a very weird behavior where ETTL or even TTL will ...
1
vote
1answer
3k views

When to use different combinations of TTL/TTL-BL and Spot/Matrix metering?

I am trying to teach myself flash photography, and I am currently confused about metering modes. In what shooting conditions would each the following metering modes be best-suited? (And why do they ...
2
votes
2answers
428 views

How important is it that the Canon 50mm f/1.4 lens does not return distance data?

I read at the photonotes website that the Canon 50mm f/1.4 USM lens does not return distance information to the camera, to be used for E-TTL II. How important is this, and should this be a ...
3
votes
4answers
2k views

Why is manual flash at the lowest power stronger than the TTL result?

I have a 500D with the 430EX II flashgun. I've taken two pictures with the camera in manual mode, one with the flash in ETTL mode and then in manual mode with the power to 1/64 and the flash exposure ...
8
votes
4answers
8k views

How does TTL flash work in manual exposure mode?

I got the Metz 44 AF-1 flash recently that is TTL capable for my Canon 550D, and have been reading around to get a better understanding of using flash on-camera (Neil Van Niekerk's article on flash ...
24
votes
1answer
10k views

What are the differences between E-TTL, i-TTL, and P-TTL?

Canon, Nikon and Pentax each have their own TTL flash metering systems, respectively E-TTL, i-TTL, and P-TTL. They all use a weak preflash that is metered and used to calculate flash power level ...
1
vote
1answer
628 views

Can I use the on-camera flash along with an off-camera SB-700 on my Nikon D5000?

I recently bought an SB-700 flash for my D5000 and I was wondering what would be my options to use this as an off-camera flash along with the on-camera flash. Is it possible? TTL cable, wireless ...
6
votes
2answers
2k views

Are there any radio flash triggers capable of P-TTL?

All the popular radio TTL flash triggers, like PocketWizard or RadioPopper, seem to be only available in Nikon and Canon flavors. Are there any models capable of transmitting Pentax P-TTL data?
10
votes
1answer
508 views

Why isn't TTL metering accurate when using a non-electronic lens?

I recently bought a Lensbaby lens and I played with it a lot. Then lens is awesome but I have one big and annoying problem and is that TTL metering fails miserably when using P, TV and M modes. I ...
1
vote
1answer
356 views

Will the “Pixel Knight TR-332” radio flash trigger work with a Canon 350D?

I am using a Canon 350D/XT and found some information on web that the Pixel Knight TR-332 radio flash may be incompatible with that particular Canon camera due to DIGIC II and lack of Flash functions ...
4
votes
1answer
1k views

How do I read the flash distance scale on the Canon 580EX II?

My Canon 580EX II has a distance scale running from 0.5m to 18m. When the flash is in manual mode, a single segment of the distance scale illuminates to indicate the maximum effective range for my ...
6
votes
1answer
257 views

Are there risks in using a third-party TTL cable?

I see that the cables that support TTL offered by manufacturers such as Canon and Nikon for using a flash off-camera are fairly spendy and that there are some third-party cables at a fraction of the ...
13
votes
3answers
661 views

What was my flash power?

When I am using a Canon flash in the E-TTL mode, how can I tell which flash power the E-TTL magic chose? For example, if I got a correct exposure in the E-TTL mode, can I easily choose the same flash ...
19
votes
4answers
17k views

What does TTL mean?

I'm new to photography and I see the term TTL all over the place. What does it mean? And how do I use it to make my pictures better?
6
votes
1answer
281 views

Can an E-TTL II cable trigger a speedlite in Manual mode

Essentially, if you own an E-TTL II (or presumably iTTL) cable of a certain length/type, is there any reason to also own a manual PC-sync cable of a similar length/type, or can the camera be fired in ...
9
votes
2answers
646 views

Inexpensive flash with full ETTL support

I've been planning to get the Canon 430EX, but I'd love to save a little cash, so I started looking at other 3rd party flashes. I've found a few that claim to have ETTL II support, but being so much ...