I don't understand the instruction manual of 420ex, Any coul

[dereklam]

According to the manual, in order to prevent the dark backgrounds behind the subject you take flash, I should use the Slow-Speed Sync.

The manual said on page 36:-
Slow-Speed Sync for Dark Backgrounds
============================
By using a slow sync speed with flash, you can correctly expose both the subject and a dark background. For automatic slow-speed sync, set the camera to the mode....


I tried to follow these instructions, but not successful!!!! Could anyone make me clear the meaning of slow sync speed? and there are 2 pictures side by side show on that page of this manual. One is "Flash with slow-speed sync" and the other is "Flash in Full Auto mode". I understood the latter term, but what means to Flash with slow-speed sync? How could I make it?


thank you very much.

[SkipD]

That feature doesn't work with the G2.

[dereklam]

SkipD wrote:
That feature doesn't work with the G2.

Oh, thank you very much for your advice. I won't do any trials anymore for this function. This totally wasted my time, as this could not work for G2.

thanks again!!!

[msvadi]

SkipD wrote:
That feature doesn't work with the G2.

Are you sure about that? Dennis Curtin's book http://www.shortcourses.com/bookstore/canon/book_canong2.htm has a section on slow sync.

[msvadi]

okay, here is the answer:

http://photography-on-the.net/forum/showthread.php?t=2724#11573

so, slow sync does work with G2

[scottbergerphoto]

"Slow Sync" is an automated procedure that you can do youself manually! It is a procedure where you set the exposure for the background and let the flash sensor control the exposure for the subject. Normally, in program mode, the camera will not shoot at less then1/60th of a second. When you set "slow sync" you tell the camera to relax and give a shutter speed for the background in a dim room or outside at night.
To do this you need to put the camera in Aperture Priority or manual. In "A" mode, focus on the background and set the Aperure for a normal exposure using the in camera meter. You could also use a light meter. Then refocus on your subject and take the picture. In Manual mode you set the Aperture and Shutter speed. Then when you take the picture the shutter will open, the flash will fire, and when the background is properly exposed, the shutter will close. Your subject must remain still even after the flash has fired till the shutter closes.The camera should be on a tripod.

[dereklam]

scottbergerphoto wrote:
"Slow Sync" is an automated procedure that you can do youself manually! It is a procedure where you set the exposure for the background and let the flash sensor control the exposure for the subject. Normally, in program mode, the camera will not shoot at less then1/60th of a second. When you set "slow sync" you tell the camera to relax and give a shutter speed for the background in a dim room or outside at night.
To do this you need to put the camera in Aperture Priority or manual. In "A" mode, focus on the background and set the Aperure for a normal exposure using the in camera meter. You could also use a light meter. Then refocus on your subject and take the picture. In Manual mode you set the Aperture and Shutter speed. Then when you take the picture the shutter will open, the flash will fire, and when the background is properly exposed, the shutter will close. Your subject must remain still even after the flash has fired till the shutter closes.The camera should be on a tripod.


Is it hard to use this approach for portrait pictures? because the subject must remain still.

[scottbergerphoto]

dereklam wrote:
scottbergerphoto wrote:
"Slow Sync" is an automated procedure that you can do youself manually! It is a procedure where you set the exposure for the background and let the flash sensor control the exposure for the subject. Normally, in program mode, the camera will not shoot at less then1/60th of a second. When you set "slow sync" you tell the camera to relax and give a shutter speed for the background in a dim room or outside at night.
To do this you need to put the camera in Aperture Priority or manual. In "A" mode, focus on the background and set the Aperure for a normal exposure using the in camera meter. You could also use a light meter. Then refocus on your subject and take the picture. In Manual mode you set the Aperture and Shutter speed. Then when you take the picture the shutter will open, the flash will fire, and when the background is properly exposed, the shutter will close. Your subject must remain still even after the flash has fired till the shutter closes.The camera should be on a tripod.


Is it hard to use this approach for portrait pictures? because the subject must remain still.

We're really not talking about that much time. You just have to remind the subject that the picture may last a second longer then the flash. This is not something I would do for casual pictures of friends. But if you find a special background that you want to capture, use it.

[dereklam]

scottbergerphoto wrote:
dereklam wrote:
scottbergerphoto wrote:
"Slow Sync" is an automated procedure that you can do youself manually! It is a procedure where you set the exposure for the background and let the flash sensor control the exposure for the subject. Normally, in program mode, the camera will not shoot at less then1/60th of a second. When you set "slow sync" you tell the camera to relax and give a shutter speed for the background in a dim room or outside at night.
To do this you need to put the camera in Aperture Priority or manual. In "A" mode, focus on the background and set the Aperure for a normal exposure using the in camera meter. You could also use a light meter. Then refocus on your subject and take the picture. In Manual mode you set the Aperture and Shutter speed. Then when you take the picture the shutter will open, the flash will fire, and when the background is properly exposed, the shutter will close. Your subject must remain still even after the flash has fired till the shutter closes.The camera should be on a tripod.


Is it hard to use this approach for portrait pictures? because the subject must remain still.

We're really not talking about that much time. You just have to remind the subject that the picture may last a second longer then the flash. This is not something I would do for casual pictures of friends. But if you find a special background that you want to capture, use it.

Actually, what the approach we are talking about is exactly what the 420ex instruction manual talking on page 36. They showed 2 portrait pictures, which one of them has both the subject (a woman) and background claimed exposed perfectly by using the slow syc speed (the approach we are talking now). However, it is impossible to get such perfect picture as the manual shown, because we could not garantee the subject to remain himself/herself still for a few seconds. Do you agree?

I think if we could find a way (good exposure on both the subject and background) for portait picture, it will be very practical because this senario is always happening in our daily life and during a tour.

appreciated for your help!!

[oilemgolem]

I agree with the procedure described by scottbergerphoto. I have used it successfully many times. For example to photograph a shaded person in the foreground with a city or mountain scene in the background. For true portrait work, the background should not be relevant; you focus and expose for the subject, choosing lighting that gives the mood you want.

[dereklam]

scottbergerphoto wrote:
dereklam wrote:
scottbergerphoto wrote:
"Slow Sync" is an automated procedure that you can do youself manually! It is a procedure where you set the exposure for the background and let the flash sensor control the exposure for the subject. Normally, in program mode, the camera will not shoot at less then1/60th of a second. When you set "slow sync" you tell the camera to relax and give a shutter speed for the background in a dim room or outside at night.
To do this you need to put the camera in Aperture Priority or manual. In "A" mode, focus on the background and set the Aperure for a normal exposure using the in camera meter. You could also use a light meter. Then refocus on your subject and take the picture. In Manual mode you set the Aperture and Shutter speed. Then when you take the picture the shutter will open, the flash will fire, and when the background is properly exposed, the shutter will close. Your subject must remain still even after the flash has fired till the shutter closes.The camera should be on a tripod.


Is it hard to use this approach for portrait pictures? because the subject must remain still.

We're really not talking about that much time. You just have to remind the subject that the picture may last a second longer then the flash. This is not something I would do for casual pictures of friends. But if you find a special background that you want to capture, use it.

I have found in the G2 manual that we could reduce the ISO Speed to 50 in order to make the background clear when shooting for portrait pictures.

[msvadi]

I think that many users of G cameras leave ISO at 50 unless shooting night scenes or macro.

[dereklam]

msvadi wrote:
I think that many users of G cameras leave ISO at 50 unless shooting night scenes or macro.

Before that, the setting was AUTO. (which I was not noticed to change to 50 before.)

-Derek

[scottbergerphoto]

dereklam wrote:
scottbergerphoto wrote:
dereklam wrote:
scottbergerphoto wrote:
"Slow Sync" is an automated procedure that you can do youself manually! It is a procedure where you set the exposure for the background and let the flash sensor control the exposure for the subject. Normally, in program mode, the camera will not shoot at less then1/60th of a second. When you set "slow sync" you tell the camera to relax and give a shutter speed for the background in a dim room or outside at night.
To do this you need to put the camera in Aperture Priority or manual. In "A" mode, focus on the background and set the Aperure for a normal exposure using the in camera meter. You could also use a light meter. Then refocus on your subject and take the picture. In Manual mode you set the Aperture and Shutter speed. Then when you take the picture the shutter will open, the flash will fire, and when the background is properly exposed, the shutter will close. Your subject must remain still even after the flash has fired till the shutter closes.The camera should be on a tripod.


Is it hard to use this approach for portrait pictures? because the subject must remain still.

We're really not talking about that much time. You just have to remind the subject that the picture may last a second longer then the flash. This is not something I would do for casual pictures of friends. But if you find a special background that you want to capture, use it.

I have found in the G2 manual that we could reduce the ISO Speed to 50 in order to make the background clear when shooting for portrait pictures.

By reducing the ISO to 50 from 100 you are making the camera 50% less sensitive to light. That means you will either need longer exposures or wider apertures. There is a limit on how wide your aperture can be set, and since you are trying to capture the background in slow sync it makes no sense to max out your aperture as you will have a very narrow depth of field- a blurry background. If you increase your exposure time(slower shutter speed) you increase the likelihood that the picture will be blurry from camera shake or subject movement. So, if we're still talking about "slow sync" or "night portrait", it's probably not a good idea to drop the Iso to 50. The ISO has no direct effect on the clarity of the background. That is a function of "depth of field" which is controlled by your aperture and the focal lenth of your lens. Large apertures and long focal lengths give blurry backgrounds and vice versa. Lower Iso's require more light- wider apertures or longer exposures.
In addition, since we are talking about a flash technique, when you drop the ISO by 1/2 you reduce the Guide Number of the flash (effective distance) by 1.4. So you may get an underexposed subject unless you adjust your distance from the subject. Take the shot, and if the foreground subject is under exposed on the LCD move closer to the subject. If you want to get technical: Distance = Guide Number/f-stop at ISO 100. If you drop to 50, divide by 1.4. If you go up to 200, multiply by 1.4. If you go to ISO 400 multiply by 2.
Fun huh?
Scott

[phidong]

Its true that slow-synchro will force the subject to stay a bit sooner, so I definitely wouldn't use it on someone flailing alround, but if they're sitting relatively still.. its no problem because the flash should freeze the action whether you're using it on first or 2nd curtain.

[scottbergerphoto]

phidong wrote:
Its true that slow-synchro will force the subject to stay a bit sooner, so I definitely wouldn't use it on someone flailing alround, but if they're sitting relatively still.. its no problem because the flash should freeze the action whether you're using it on first or 2nd curtain.

They have to stay completely still, otherwise the ambient light reflecting off of them will register as trails on the picture either in front of them in "slow sync", or behind them in 2nd curtain sync.

[Mind Socket]

I envy your patience, scott. :)