Aiming a better beamer and flash?

[Cal Walters]

I am using a Canon 7D with a Canon 100-400 zoom and a 580exII flash on a Wimberly flash arm. I have the flash set to 50mm. I have noticed that the center is falling either below or above the target when I have the lens set on 400mm and I am using either the two most horizontal / perpendicular preset angles that the flash has. The lowest lock in position actually has a flashing warning on the flash unit saying it is pointing below horizontal. I tested it today at a 25' distance and found that the center point of the flash was ending up about 1 foot above the target when it was set on perpendicular. Is there a way to make adjustments to any of these pieces to realign the accuracy of where the flash falls?

[Diane Miller]

My 580 drives me nuts -- there is way too much slop in the D-tents, and no good way to shim it. That lowest position is for very close-up work, hence the flashing warning. The next position up is allegedly horizontal. The others are for bounce flash. With a 300mm lens on a full frame, my "horizontal point" falls a little low, but at longer focal lengths coverage is OK. There is some specification for the zoom to set on the flash, I think 50mm, but I haven't been able to see a difference with it so just leave it where it was before.

[Ian Wilson]

I am using a Canon 7D with a Canon 100-400 zoom and a 580exII flash on a Wimberly flash arm. I have the flash set to 50mm. I have noticed that the center is falling either below or above the target when I have the lens set on 400mm and I am using either the two most horizontal / perpendicular preset angles that the flash has. The lowest lock in position actually has a flashing warning on the flash unit saying it is pointing below horizontal. I tested it today at a 25' distance and found that the center point of the flash was ending up about 1 foot above the target when it was set on perpendicular. Is there a way to make adjustments to any of these pieces to realign the accuracy of where the flash falls?

I use a 600EX-RT and find that with the Better Beamer mounted it aims a little low. There is some compliance in the flash head that allows the cantilevered weight of the BB to causes the head to sag a bit. I found this very frustrating and made up a little wooden wedge with some shallow grooves that I gently push under the head to jack it up a whisker. I tied the wedge on a string around the flash head so that I would not lose it when not in use. It is inconvenient but works provided one remembers to insert the wedge.
Cheers, Ian

[Mike Milicia]

If you are using the Wimberley M-3 flash arm as pictured here, you can loosen the set screws a tiny bit which will allow you to pivot the entire flash head to get the angle you need. If you adjust and leave the screw exactly where it needs to be for your setup, then it is also easy to consistently mount the flash at the necessary angle.

[Randy Stout]

Mike:

An excellent point, and I do exactly the same thing. I figured out how much to back it out by shooting against a white wall in a dark room and observing where the flash pattern fell. It is a bit of a rough measurement, since it varies with distance, but I was able to tweak it to get pretty consistent coverage.

Every time I mount the flash, I recheck the setting, as the knob can allow it to slip a bit .

Cheers

Randy

[Cal Walters]

Mike, Randy, & Ian, Thanks for the Suggestions. I am using the F-1 bracket, but the arm looks very similar. I'll take a look tonite.

[Mike Milicia]

Wimberley uses a modular system. One of the components of the F-1 system is the M-3 arm as shown here.

[Diane Miller]

Thanks, Mike! I never thought that it might be adjustable. Will do it!

[Cal Walters]

Yes, Minke, I tried it tonite - it was the perfect suggestion. I did not realize those screws had that functionality. I also found that I had had the arm in the highest notch of the vertical extender. By lowering it to the lowest level, I had much better alignment - then the screw adjustments really helped dial it in. Randy, I think I also need to set up a longer range as you are suggesting so I'll know the adjustments for various distances.

[tomlamb47]

I know I'm late responding to this thread but I found a solution to aiming the Better Beamer. Get yourself a Harbor Digital Flash Extender. I've had one now for several months a found it to be fantastic. No more aiming problems. I just put it on my 580ex II and fire away. I fits snuggly onto the flash and no velcro. The only negative is that it doesn't fold up. So if packing space is important this may not work for you. But it works great for me, I've got a big truck .

[Barry Ekstrand]

Tom,

This is interesting. Have you had an opportunity to do a 'quantitative' test of the flash beam of Harbor vs. the Better Beamer? Besides sitting on the flash snugly I see that the Harbor fresnel lens is by design much closer to the flash source than with the Beamer. Although I realize both of the fresnel lenses will create a linear beam of light I'm curious if the differences in standoff distance and size of the fresnel lenses of the 2 designs result in a difference in the spread of focused flash beam as a result.

Barry

[tomlamb47]

Hi Barry,
No I haven't done a side by side comparison of the two. Actually after using the Habor Digital extender the first time I haven't gone back to the Better Beamer. But my unqualified view is that the BB may be a tad brighter but not by much. The overall size of the Habor extender is slightly smaller and it also has a diffuser inside the box to help spread the light. Like I said the only downside is it doesn't pack as well as the BB.

[Diane Miller]

I started to do the adjustment for my Better Beamer suggested by Mike, but decided first to see how bad the sagging was. It looked like a degree, maybe. Sloppy, but was that significant?

Short answer -- no. I put on the 70-200, carefully aligned the BB fitting on the flash head, and stood about 15 ft from a shaded wall. At 70mm, there was significant vignetting from the flash, but no major sag toward the bottom of the frame. At 200mm, illumination across the frame was very even. So at 300-840mm, where I normally use the BB, I wouldn't have any alignment issue.

While I was at it I did a further check. If I'm remembering right (and I may not be), the BB instructions say to set the flash zoom to 50mm. That always sounded wide, to me. So I went to all M and compared 50mm to 105mm (the max zoom on my Canon 580). I got slightly more exposure, maybe half a stop, at 105. Illumination was still very even.

Bottom line -- I could use a Fresnel lens with an even tighter beam for most of the uses I have for it.

[Cal Walters]

Interesting Diane. I found mine to be more out of waco, and the screw adjustments worked well to get it realigned. Tom, so do you think the 2 stops that the Harbor Digital Flash Extender claims to add is about right? The BB indicates 3 stops. But I am trying to understand if it can be aimed. Is it adjustable? For my situation it is packing for a birding trip where space is limited.

[tomlamb47]

Cal, Since my last post in this thread I did a basic test with both the Better Beamer and the Harbor Digital Extender. I shot from a distance of about 60 feet in manual mode and only varied the flash exposure compensation on my 580EX II from 0 to -3. And I couldn't tell a difference between the BB or the HD at a given setting. Now to answer your, the HD cannot be adjusted. It fits snugly on the head of the flash and it cannot be moved. And I've yet to find it misaligned. Perfect fill flash every time. At least in how the light from the flash covers the subject. No dark tops to the frame and hot spots on the bottom like I was getting with the BB. Looking at the HD extender's front lens the demensions are, 6 1/8" wide, 3 7/8" high and 5" deep. So if that size is too much space to give up, then the HD isn't for you.