bill_goldman

The purpose of the preflash is to provide a means for the camera's evaluative meter to get a proportional reading so that the final exposure provide a balance between the main subject and the background. When the flash unit is in manual mode, an evaluative reading is meaningless and unecessary since it can't affect the exposure since it is no longer controlling the flash output. My interpretation is that there is no preflash in flash manual mode. It is also consistent with the instruction manual as it specifies the use of a flash meter in that situation.

 

It should be easy to check as when using E-TTL mode with an on camera EX flash unit, you can see the preflash illuminating the subject thru the viewfinder before the mirror rises since the evaluative measurement is performed before the mirror rises. If there is no preflash in manual mode, it should be apparent thru the viewfinder. After I use up the film in my camera, I intend to check it out, even though I am convinced I am correct.

I purchased one several years ago from B&H when I was in New York. When I got home I discovered the installed 9 volt battery was dead. I installed a new battery and discovered it seemed to be working regardless of whether the switch was in the ON or OFF position. Although the literature says it does not draw battery power when a flash unit is not attached, I'm not sure if it was operating exactly as designed.

Anyhow, the way it works is it triggers the attached flash unit (slave) in response to another flash (master) and shuts off the slave when the master shuts off. In other words it emulates the master flash duration. (The output of a dedicated flash unit is controlled by the camera by shutting off the flash output after the required light is achieved.) Other than experimenting with the Lite-Link, I never really felt it was reliable or its effect predictable enough. I don't know what your needs are or what equipment you have. Maybe the Lite-Link is just what you're looking for. However, if you want an elegant, no-compromise, wireless, multi-flash system that really works, I highly recommend 550EX flash units with one of the EOS type A cameras.

You're not the only one confused. I guess my assumption that the 550EX was operating as a generic optical slave, was not exactly correct. Although I verified the slave was successfully triggering from the master 550EX, whether or not it was set as master, and even when the master and slave were set on different channels, there must be some coded signal in the master's flash output to which the slave responds. Perhaps Canon designed it this way so the slave will not respond to other extraneous flash units.

Well, my curiosity got the best of me. I configured one 550EX as a slave and set it to manual, 1/4 power. I then was able to trigger it by manually firing my other 550EX. Note: With both units in manual mode and neither having a group assignment, it is clear that the slave in manual mode acts exactly as any flash unit with a built-in slave sensor (typical for studio type monolights, such as White Lightning). In fact, the second unit does not even have to be configured as a master for this to work and the slave will most likely respond to any generic flash. However, if you trigger the slave with an on-camera or pop-up flash in E-TTL mode, a hand-held flash meter will not work properly, due to the E-TTL preflash so make sure it's a manual flash or in manual mode. I knew the 550EX was an excellent unit but it is also even more versatile than I realized.

According to the 550EX instruction book, manual flash CAN be set with a 550EX SLAVE unit by holding down the MODE button for at least 2 seconds until M starts blinking. Then use the SEL/SET button and + or - to set the desired flash output. (This procedure is different than the normal way of setting the unit to M mode.) The master unit 550EX (or an ST-E2 transwitter) will then trigger the slave unit just like any normal optical master/slave set up. Since both 550EX units are in manual mode, not E-TTL, there will be no preflash and a hand-held flash meter should work. I have not actually tried this but I have no doubt that it will work. However, since I do have 2 550EXs and a flash meter, I intend to verify it next time I set up for wireless flash to satisfy all the doubting Thomases.

If you check your instruction manual for the 550EX, you will notice it is divided into two sections, one for type A camera bodies and one for type B bodies. Both sections detail how to use a wireless multiflash settup with the flash units in manual mode and specify the use of a hand-held flash meter. Check it out! I didn't make this up.

There is no preflash when the unit is in manual mode. There is also no preflash when the 550EX is used with a type B camera, e.g., an A2, as it defaults to TTL mode. There is only a preflash in E-TTL mode (only enabled when used with a type A camera (EOS-1v, 1D, D30, D60, EOS-3, Elan 7E, etc.).

The A2 does not support ETTL flash with the 550EX. The flash reverts to TTL and there is no preflash. You can perform wireless multiple flash but you have to set both units to manual and use a flash meter. You can also set up a ratio by individually adjusting the fractional power output on each flash unit and positioning them properly with respect to the subject.

If I recall correctly, I believe Canon originally defined AI as in AI Servo as "Automatic Intelligent" Servo. This pertains to the predictive autofocus feature in which the camera predicts where a subject will be by sampling its speed and direction. Artificial Intelligence seems to imply something beyond straight computer calculations.

If you are referring to the built-in diffuser on the 540EZ (and on the 550EX), it has two uses. Firstly, by pulling it out fully and dropping it in front of the flash tube (it's hinged), it will provide coverage for extreme wide angle lenses (e.g., 17mm). Don't use brute force or you can pull it off completely! The second use is by pulling it out to the first stop or resistance where it is still perpendicular to the flash tube, you can then tilt the flash head straight up and the diffuser will provide catch lights in the eyes for portraits.

This is a somewhat surprising question as the more common question is how to accomplish the opposite effect (well exposed background). However, the answer to your question is yes. The flash will properly expose the main subject as long as the focusing point(s) are on it and a properly chosen manual camera setting is used to under expose the background. This is true for both camera/flash combinations.

The camera uses power only when it is switched on so it is not necessary to remove the battery if the camera will not be used for a period of time. However, to answer your question, setting the switch on the BP-E1 between positions removes power from the camera. To verify this, switch on the camera and move the switch to an intermediate point and you will note the LCD screen goes blank. You can accomplish the same thing by placing the switch at the LR6 position and pressing the battery magazine release button.

BTW, Canon specifies the 1.4xII as the original 1.4x has been discontinued. However, I recommend you buy one if you can get it at a really good price. You will probably not be able to tell the difference in performance between the two versions. Also I meant the EOS-1D, not the D1.

The original 1.4X extender and the new mark II version are optically identical. The only differences are the addition of seals at the mounting surfaces to mate with the seals on the EOS-1V and D1 as well as the newest super telephotos, and better internal anti-reflection treatment. The new version of the 2X is a new optical design.

If you want to find out what owners of Canon digital SLRs have to say about their cameras, lenses, etc., I suggest you go to the following site:

 

www.dpreview.com/forums/forum.asp?forum=1019

 

Also, be aware that the D60 is in short supply and you'll have to get in line and be prepared to wait if you want to purchase one.

Yes, you can use your 550EX and 420EX in the wireless, manual mode. Even though you cannot make manual power adjustments on the 420EX, you can set a ratio (E.g., 4:1)on the 550EX master, effectively reducing the power of the 420EX slave. Of course, you will need to use a flash meter to determine exposure. (This is described on page 72 of the 550EX instruction manual.)