Need help, flash settings,

ginger_55 · June 5, 2006

for fill, and for straight flash.

I have a Gary Fong diffuser, when I first used it, it worked great for me.

Yesterday, it worked OK in the church but for fill outside, I was over exposing everything. I just felt totally clueless. I can't listen to the Gary Fong DVD as it is not captioned. My husband listened to the first part and said this is all you need to know, turn it this way for this and that way for that. Nothing else. I have read more than that on here. My husband is not a "talker".

I thought I read somewhere "here" to use the P setting when using flash, so I was using that. Then when everything was being overexposed, I switched to the AV setting: still over.......... Eventually I put it on the TV setting which appeared to work better.

I had put it the week before on -2/3, the flash unit and I think I used the P setting, got great photos inside and out. Then I thought I read on a thread on dGrin to use it on 0 for fill........... Neither of those were working for me yesterday. And those were on the outside shots, then inside with the performers................I gave up. I did get some good photos but please..........does someone know what I need to know to operate with.

I own a Sigma 500 Super flash, and the cloudy GF thingy with the dome thingy.

I need to be able to use it generally for fill.............

outside, and inside.

and I need to know the usual setting for just reg flash with the GF on there.

When it works, I love it. When it doesn't, my hair starts to fall out!

I know that there is no one setting fits all, but just a couple would help me get going.........the more usual ones would help, both for the camera and the flash together with the GF thing on it.

Plus, minus, fill, indoors, outdoors. that is really two settings......or four if you count the camera as one unit and the flash as another.

Can anyone help me with that?

ginger

photocat · June 5, 2006

Can anyone help me with that?

ginger[/QUOTE]

I will be reading too Ginger, as I have the same hair problem as you have when the flash starts acting up.
Lots to learn about flash I find, and hard to learn out of books. It must be hard for you if you can't even listen to explanation...

pathfinder · June 5, 2006

Ginger,

If there is moderate ambient light - enough to take a nice shot - then shoot in Av mode with flash - this will set the exposure by the ambient light and only emit enough flash to illuminate the foreground subjects. If the flash needs toned up or down slightly, add or subtract maybe 2/3 stop of Flash Exposure Compensation ( not exactly sure how to do this with the Sigma flash - with the 580ex or the 430ex you just dial it back on the flash.) This works great outdoors in the sunlight or with backlit subjects.

Better than shooting in P, is to put your camera on Manual mode and enter the aperture and shutter speed yourself - the flash will then meter and emit the proper amount of light. Remember that the 20D does not synch at shutter speeds higher than 1/250th unless the strobe is set for High Speed synch too. If you shoot in full auto rather than P, the ISO is set by the camera - NOT recommended!

Both of these two methods will work just fine with Fong's Lightshpere diffusion gadget.

Only use P when there is not enough ambient light to shoot in Av - P will be using straight flash illumination.

Check the settings on your flash and your camera - you should not get overexposures unless a setting is off

ginger_55 · June 6, 2006

Thanks, Pathfinder........that was my thought on Sunday re AV. Didn't work, don't know why.
I guess I will have to try it again..............frustrating. I had a guy who wanted his photo taken, I think he was drinking, so I could see if it worked and come back. I did P, I did AV, I dialed down ON THE FLASH. didn't work, overexposed. Went to TV, and it seemed to work.

But that was my thinking re AV, as if there is not enough ambient light and I would accidentally shoot in AV there would be a lag which would signal me that I was in AV. So with the bright sun, I thought there would be no lag and all would be cool.

dogs just woke me up to take them outside...........saw this and thought I would answer.

I don't know what ISO the camera was on..............tried lowering that, too.

did all sorts of things......

ginger (for what it is worth, the Sigma is not a bad flash but it is not as good as the Canon in many ways, starting with the manual. I got it because it was cheaper and everything I read said that it was as great as the Canon at a cheaper price. It feels cheaper, the manual is not as good, it works similarly. But it does not dial down, it is a bit different on that and a few other areas. I have seen Bill's company's Canon, so for other people, if you can afford it, get the Canon. I use Bill's manual a lot.)

I have had problems with AV and the flash on my camera. I would be concerned that it was the camera, but this was Bill's camera.............mine is held up at the shop and no one knows why. Seems they never got my money, though it cleared our bank. I hate Canon! Nice people, bad service, or just me and bad luck.

thanks for trying to explain PF.

jfriend · June 6, 2006

Trying stopping down some

ginger_55 wrote:

for fill, and for straight flash.

I have a Gary Fong diffuser, when I first used it, it worked great for me.

Yesterday, it worked OK in the church but for fill outside, I was over exposing everything. I just felt totally clueless. I can't listen to the Gary Fong DVD as it is not captioned. My husband listened to the first part and said this is all you need to know, turn it this way for this and that way for that. Nothing else. I have read more than that on here. My husband is not a "talker".

I have thoroughly enjoyed using fill flash outdoors, but I've overexposed a few of my own. Usually the problem is that when using the flash, the max shutter speed (depending upon the camera) is somewhere around 1/250 or 1/500th. If it's bright outside and your aperture is too large (sometimes set that way to try to get blurred backgrounds in portraits), then there's just too much light and there's nothing the camera can do, particularly when you then add the light from the flash. This happens most often if you're in A-mode with a large aperture in very bright light while trying to use fill flash.

If this is the issue, the solution is to either use an ND filter (if you really want to keep the aperture wide) or make sure you stop down a bit more so there isn't too much light at 1/250th shutter speed or some combination of the two. I usually just stop down and have to give up on the blurred background.

I don't know what kind of camera you have, but you should be able to check on the exposure to see if your aperture is too large with your camera's meter even before you take your first shot. Or just turn the flash off and look at what the camera would take the picture at. If you're in A mode and the shutter is >1/250th, then you need to stop down more.

ginger_55 · June 6, 2006

Thanks, John: that speaks to my problem and is probably what happened. I just routinely keep my aperture pretty open. F 8 is standard for me. F 11 is a high number..........I can fix that. I usually shoot birds, smile, and that always worked for birds, I needed to keep the speed up then. So, shooting people on a dock, well, I don't really care and can address that easily.

ginger

pathfinder · June 6, 2006

jfriend wrote:

I have thoroughly enjoyed using fill flash outdoors, but I've overexposed a few of my own. Usually the problem is that when using the flash, the max shutter speed (depending upon the camera) is somewhere around 1/250 or 1/500th. If it's bright outside and your aperture is too large (sometimes set that way to try to get blurred backgrounds in portraits), then there's just too much light and there's nothing the camera can do, particularly when you then add the light from the flash. This happens most often if you're in A-mode with a large aperture in very bright light while trying to use fill flash.

If this is the issue, the solution is to either use an ND filter (if you really want to keep the aperture wide) or make sure you stop down a bit more so there isn't too much light at 1/250th shutter speed or some combination of the two. I usually just stop down and have to give up on the blurred background.

I don't know what kind of camera you have, but you should be able to check on the exposure to see if your aperture is too large with your camera's meter even before you take your first shot. Or just turn the flash off and look at what the camera would take the picture at. If you're in A mode and the shutter is >1/250th, then you need to stop down more.

Excellent point John.

A good time to consider High Speed synch on the flash then right?? You could then shoot at 1/1000th or whatever you needed.

That may be why Ginger found Tv worked better for her - the aperture got stopped down.

jfriend · June 6, 2006

Tv mode works because it frees up the camera to set a smaller aperture

pathfinder wrote:

Excellent point John.

A good time to consider High Speed synch on the flash then right?? You could then shoot at 1/1000th or whatever you needed.

That may be why Ginger found Tv worked better for her - the aperture got stopped down.

Yeah, you're right. I'm not a Canon guy so I just had to look up what Tv was. It appears to be shutter priority mode where you set the shutter and the camera sets the aperture. That absolutely will fix it because it will free up the camera to pick a small enough aperture to make the exposure work at a mid-range shutter speed that's appropriate for the flash sync. It could also have been addressed in Av mode by just setting the aperture to f/8 or f/11 (depending upon how much light there was).

I've never really understood or used high speed sync for the flash. On my Nikon D70, it will do normal flash sync up to 1/500th. I know there are some unsupported ways to go faster than 1/500th, but I think it involves tricking the camera by covering some pins on the flash unit and setting the exposure manually. I don't know about Canon cameras in this regard.

Scott_Quier · June 7, 2006

I'm not the expert that PF is, but here are a couple of thoughts:

I believe the max X-Sync speed on the 20D is 1/250
Set the camera to AV and check the calculated shutter speed for the selected aperature? Is it faster that 1/250. Close it down a bit.
Is your aperature smaller than you want? If so, add an ND or set to lower ISO and go back to step 2.
Set the flash explosure compensation to -1/3 or -2/3. This will get you the flash fill you are looking for. To do this on the Sigma 500 DG Super, press the "Sel" button (once, maybe twice - I'm doing this from memory). Then press the "+" or "-" button to get the desired compensation. Press the "Sel" twice again to set it.

I've not yet had a chance to play with the high-speed sync, but that looks like a lot of fun.

pathfinder · June 7, 2006

Scott_Quier wrote:

I've not yet had a chance to play with the high-speed sync, but that looks like a lot of fun.

Scott,
What Canon and others call High Speed Synch really goes back to the days of using focal plane flash bulbs. The strobe emits multiple sequential flashes of light so that a fast shutter speed will be evenly illuminated.

The reason this is necessary for higher shutter speeds, goes to the nature of a focal plane shutter like an SLR uses.

Focal plane shutters are not inside a lens, but in the camera body immediately in front of the film or the sensor. There are limits to how fast the focal plane shutter curtains can move. At shutter speeds slower than about 1/250th ( the 20D X-synch maximum) the whole sensor is uncovered for the duration of the exposure. But at 1/1000th and higher, the whole sensor is NEVER wholly exposed.

One curtain opens, and before the first curtain reaches the opposite end of the frame, the second curtain begins to close, so what you really have is a slit of various width, that passes across the sensor. The higher the shutter speed, the narrower the width. At 1/8000th the slit is very narrow, but may take 1/250th second to pass across the entire sensor. This was true for film SLRs also. Obviously, a very brief electronic flash exposure will only illuminate a brief slit on the sensor or film.

SO they used focal plane flash bulbs - that is flash bulbs that ignited and stayed ignited for about 1/15th second or so, and thus illuminated the film evenly for the entire duration of the shutter curtain slit passing across the film.

In High Speed Synch, the 580ex or the 430ex, emits a series of flashes, rather than one very brief flash, thus emulating a focal plane flash bulb. I use High Speed synch with the camera in manual mode frequently. It lets you chose the aperture and shutter speed, as well as ISO, that you prefer.

And I am certainly no expert! Just a guy with a couple cameras, here to learn, like everyone else.

saurora · June 8, 2006

pathfinder wrote:

And I am certainly no expert! Just a guy with a couple cameras, here to learn, like everyone else.

Pathfinder, you may not consider yourself an expert, but time and again, you have proven yourself very knowledgeable, and you are definitely an expert at explaining things to technically-challenge people like myself! Thanks for this great explanation!!!

pathfinder · June 8, 2006

saurora wrote:

Pathfinder, you may not consider yourself an expert, but time and again, you have proven yourself very knowledgeable, and you are definitely an expert at explaining things to technically-challenge people like myself! Thanks for this great explanation!!!

Thanks, Saurora.

Scott_Quier · June 8, 2006

pathfinder wrote:

Scott,
What Canon and others call High Speed Synch really goes back to the days of using focal plane flash bulbs. The strobe emits multiple sequential flashes of light so that a fast shutter speed will be evenly illuminated.

The reason this is necessary for higher shutter speeds, goes to the nature of a focal plane shutter like an SLR uses.

Focal plane shutters are not inside a lens, but in the camera body immediately in front of the film or the sensor. There are limits to how fast the focal plane shutter curtains can move. At shutter speeds slower than about 1/250th ( the 20D X-synch maximum) the whole sensor is uncovered for the duration of the exposure. But at 1/1000th and higher, the whole sensor is NEVER wholly exposed.

One curtain opens, and before the first curtain reaches the opposite end of the frame, the second curtain begins to close, so what you really have is a slit of various width, that passes across the sensor. The higher the shutter speed, the narrower the width. At 1/8000th the slit is very narrow, but may take 1/250th second to pass across the entire sensor. This was true for film SLRs also. Obviously, a very brief electronic flash exposure will only illuminate a brief slit on the sensor or film.

SO they used focal plane flash bulbs - that is flash bulbs that ignited and stayed ignited for about 1/15th second or so, and thus illuminated the film evenly for the entire duration of the shutter curtain slit passing across the film.

In High Speed Synch, the 580ex or the 430ex, emits a series of flashes, rather than one very brief flash, thus emulating a focal plane flash bulb. I use High Speed synch with the camera in manual mode frequently. It lets you chose the aperture and shutter speed, as well as ISO, that you prefer.

All this I was eventually able to extract from my flash manual and a couple three pages that Andy turned me onto. However, you have, once again, made things a lot easier to understand than most of what I was able to extract. Thanks for the clarification.

pathfinder wrote:

And I am certainly no expert! Just a guy with a couple cameras, here to learn, like everyone else.

We'll just have to agree to disagree on this one. So there!

pathfinder · June 8, 2006

Now I'm blushing.....

Need help, flash settings,

Comments