Use and Abuse of the Better Beamer

[Jay Gould]

Hi, could/would those using the BB post some Tips/Tactics/Tutorials regarding its use? If this has been done already I haven't found it; sorry in advance :o and any citations gratefully appreciated ;) :).

My gear pertaining to the BB: 300 f/2.8 with a Markins plate long enough to attach my Wimberley flash bracket, EX 580, BB, Canon flash extension cord.

Cheers, Jay

PS: If this belongs in the Gear Forum rather than the General Discussion Forum, feel free to move it (I know you do anyway! :cool: )

[Mark Dumbleton]

Im not very experienced in the use of a BB, but can say you should set the zoom on your flash manually to 50mm. Apparently that is the recommended setting. And dont let the sun reflect its rays through the beamer and onto any gear. ITS BURNS LIKE A MAGNIFYING GLASS! Not good.

[Fabs Forns]

The way the beamer works is that it widens the light output at 50mm, at 105mm in narrows to spotlight beam.
It works best at focal lengths of 300mm and if the subject is very close it's best to take the plastic off.

[Alfred Forns]

Hi Jay Have to repeat the warning by Mark and Fabs !!!!! .... careful leaving it aimed at the sun !!! I think just about every flash has a few melted spots !!!! ... I got my fare share but haven't destroyed one !!!

... moved over from Gen Topics !!!

[Ed Cordes]

I too learned the hard way about the BETTER BURNER (beamer). I have burn marks on the hood of my 100-400 as well as my old 550 EX flash. Nothing that interferes with operation, but lesson learned. I remove the lens when not actually making images.

[ChasMcRae]

It is funny that it took me a year to find why I had melted areas on my flashes.
That was many ,many yrs. ago until reports came out and i said-DUH !
Chas.

[Jay Gould]

Hi, thus far for my 300 f/2.8:

1. Don't let the sun shine into the lens as it will burn the 580.

2. Set the 580 zoom manually for 50mm.

3. ?? Suggestion for power levels depending upon situation? For example, and this is the only place I have seen this consistently mentioned, Artie, always the teacher - love it! - always indicates his EC changes and his fill flash settings (+?; -?) with his images.

Are there any rules of thumb pertaining to flash power with the BB.

I guess I am thinking in similar terms to the application of the Sunny 16 rule and when, under different circumstances, you increase or decrease EC because of the tonal quality of the scene.

Thanks, Jay

[Magnus Thornberg]

I use the BB with my 300/2.8L IS USM and it took ½ sec for the sun to do burnmarks on my 580 flash:( I set the zoom at 50mm and i often set it to -1,7 to -2 stops! It is hard to say how to set the flash because the light changes the whole time!

/Magnus

[Dan Brown]

Hi Jay. I have used a BB or a fresnel lense of some typy for over 20 years with lenses from 200mm to 600mm. I have found that the zoom setting is not really critical, especially for a fill-light application, but I still try to keep it set at 50mm. The burn stories are very correct! I have burned many strobes but never have I ruined one with the fresnel lense. As for power settings, I set my camera/strobe for high speed sync TTL, manual exp, and start with -2 EC then chimp the results and adjust as needed. For close subjects (about 6 feet or closer), be careful that the strobe is aimed fairly accurately as you can experience a fall-off of light in the upper or lower portion of the frame. Another benefit to using the fresnels is that you not only gain stops of light, you also extend the battery life of the strobe versus no fresnel in place. Also, don't worry about if the fresnel gets dirty or scratched as this has little or no effect on the output of the strobe, according to my tests in the past of very dirty lenses versus clean, new ones using a flash meter. Learn to optimize this little piece of equipment and I think you will like what you can do!

[Mike Milicia]

Are there any rules of thumb pertaining to flash power with the BB.
I guess I am thinking in similar terms to the application of the Sunny 16 rule and when, under different circumstances, you increase or decrease EC because of the tonal quality of the scene.

I am by no means a flash expert and there is way more to this can I put in a post but I can tell you the basics of what I have picked up from various experts over the years
(much of it from the Flash portion of Chas Glatzer's Technical Series) . I'm sure others will chime in to add more detail and/or correct anything that I get wrong ;)

When using flash in ETTL, the proper Flash Exposure Compensation (FEC) will depend on the tonality of the scene being metered (flash uses Evaluative metering)
in the same way that that the ambient EC depends on tonality. But you don't need to do anything different for the BB as its effect is taken into account when the preflash
is done to determine the Flash exposure. You can also use Flash Exposure Lock, which serves a purpose analogous to Autoexposure Lock for the ambient exposure.
A brief summary of all this can be found here :

http://cpn.canon-europe.com/content/...ompensation.do

This dependence between proper FEC and the tonality of the scene is one of the main reasons why Manual Flash can be useful in many situations as it eliminates the need
to predict how the flash's evaluative metering will react to a particular scene. Manual Flash also relieves you from having to reconsider your FEC each time the scene changes,
e.g. goes from light to dark BG. When using Manual Flash, you are manually setting the flash power based on the distance to the subject vs. the distance at which the flash will be
effective as shown on the distance chart on the back of the flash. In this case, you DO need to consider the BB as the effective distance readout on the back of the flash has
no idea the BB is in use and the BB approximately doubles the effective distance of the flash. With Manual Flash, there is no need to do FEC based on the tonality of the scene
but you still need to (manually) set FEC based on whether you are trying to achieve balanced flash or fill flash and if fill flash, how much. For example, let's say for a given
ambient exposure, the flash distance chart shows that the flash will be effective (as balanced flash) at 40 feet. If the subject is 40 feet away and you want fill flash at -2,
you would reduce the flash power until the distance chart reads 20 feet (2 "stops" less than 40 feet). If you are also using the BB, you would need to reduce the power by
another 2 stops to account for the extra reach of the BB, so you would reduce flash power until the distance chart reads 10 feet.
Of course, using Manual Flash is only practical in situations where the distance to the subject is constant or can be predicted in advance.

All that said, for fill flash with birds, you can usually get very close to what you need by just using flash in ETTL, and setting compensation to between -1 and -3.
One good guideline for this is to start around -2 2/3 in low light and check the result on the LCD. In brighter light, start with less compensation, i.e. -1 or -2.
The brighter the light, the more fill flash you will likely need to get the desired result of filling in the shadows. One good thing about the fact that the flash cannot usually
recycle fast enough when shooting a burst is it gives you the opportunity to see the difference on the LCD between how you have the flash set and no flash at all.
Just know that at a given FEC setting in ETTL, your results may change a bit if the tonality of the scene changes. If you want to get consistent results at a given
distance regardless of tonality, Manual Flash is your best bet.

[Robert Gravel]

I do what Mike just said...the brighter the light, as in full sunny day light, I use FEC of -1 /-2 and in lower light such as overcast days I use even less.

I tend to prefer that flash should account for a very small percentage of the whole exposure, maybe 5 / 10%.

[Mike Veltri]

I have made a cover for my better beamer, and don't worry about the sun burning the flash or my lens. I recommend everyone covering the top and bottom of the beamer.

[Tell Dickinson]

I have made a cover for my better beamer, and don't worry about the sun burning the flash or my lens. I recommend everyone covering the top and bottom of the beamer.

Have you got a picture of this Mike ?

Tell

[John Chardine]

I've used my flash extender or "Better Beamer" (BB) quite a bit over the past year. My experience is as follows:

1. Flash of any sort, including with the BB does not work well on black birds.
2. When the ambient light is low and the bird's pupils are open, the BB will often produce an unpleasant "steel eye" effect. I avoid using any flash in very low light conditions such as tree shade because of the disturbance effect on the birds.
3. I normally set my flash to ETT-L. The compensation I set depends on the working distance from the subject. With long lenses you are often working beyond the reach of the flash even with a BB attached and if you have the flash set to H-synch, you are losing flash output to-boot (in H-synch, flash output declines as the shutter speed goes up). In these cases I might try no compensation in ETT-L mode or switch to Manual full-blast to see if I can get some light on the subject. At minimum focus distances out to maybe 25' or 8 m I normally use -1 2/3 and will play with this to get a pleasing result- i.e., no too much flash, just enough to fill the shadows a little.
4. Jay- be very aware of pointing the BB in ANY direction towards the sun, not just directly at it. Just don't do it at all! E.g., the sun can be overhead and you are shooting at a low angle but in the direction of the sun and the BB can then project a very hot spot onto the top of your lens instead of the flash itself. I have been meaning to make a small cloth cover that wraps over the fresnel lens when not in use and holds with a small piece of Velcro.