Arms length

[Safety Stop]

What is the best config for arms (length and how many segment) for a photo rig (with Nikon D7100) with double strobes?

 

[bvanant]

There are quite a few configurations out there that people all swear are the best. Personally I use one 8 inch (200 mm) and one 5 inch (125 mm) arm for each strobe.

Bill

 

[tamas970]

For wide angle shots: the longer the better if you want to turn a pea soup to gin. Practical long-tentacle setup: 2x12" segments for each strobe. This is already quite cumbersome to handle (up to 4ft=1.2m span!)
For macro: flexibility is more of an issue, here you can easily provide a 90° illumination with a single 12" flex arm.

What is the best config for arms (length and how many segment) for a photo rig (with Nikon D7100) with double strobes?

 

[Interceptor121]

You generally have two segments and 3 clamps.
Strobes cover around 100-110 degrees so the further distance you can cover depends on the strobe arms
With the 5+8 inches segments bill has mentioned you can cover well something around 12-15 inches away. For subjects further away you need longer arms if you want to ensure you are hitting the subject with the edge of the light instead of frontal
In theory to cover something one meter away you need 2.8 meters distance between the strobes, you can see this is not that practical...!
With two 16" arm segments which is the largest you find on the market you can cover subjects to 80 cm distance

However the issue is that those arms length are going to be good for wide but not that practical for close up and working in small spaces so most people tend to work with a combo of 5+8 this is perfect for macro and also works well for close focus wide angle

 

[bvanant]

You can actually take pictures of things more than 3 inches away? Wow, I never new that, now I have to try it :cool2:
Bill

 

[AussieByron]

I use the same lengths as Bill (8 inch and 5 inch). I mainly shoot wide angle and never have my strobes out wide. You dont need to have extra long arms to shoot wide angle its all about strobe positioning. One can simply move the strobes back behind the lens and angle them out from the lens which gives great coverage. Also if you have long arms out wide you can not get really close to big animals as the strobe will not be covering the subject if its right in your face.

Regards Mark

 

[Interceptor121]

I use the same lengths as Bill (8 inch and 5 inch). I mainly shoot wide angle and never have my strobes out wide. You dont need to have extra long arms to shoot wide angle its all about strobe positioning. One can simply move the strobes back behind the lens and angle them out from the lens which gives great coverage. Also if you have long arms out wide you can not get really close to big animals as the strobe will not be covering the subject if its right in your face.

Regards Mark

If you angle the strobes out you can cover subjects further away however the distance from the strobe itself will be increased so better be a powerful strobe
Even with long arms you can cover close subjects if you fold them on themselves however you now have a rig that is one foot wide and 20" tall that is far from ideal but can be m option if you are 100% sure you will shoot at 80-100 cm distance

 

[AussieByron]

So how can having big long strobe arms out wide make the same light go further than say if you used my suggestion of having strobes close in behind the dome and angled awat from the lens slightly?

 

[Interceptor121]

Think about two beams of light with a given angle
If you spread the arm wide and point the strobe forward the two beam meet in the center and illuminate forward with the same angle of one of the strobe
If your strobes are closer and you point them outward so that they meet in the same point as above the cone of light you are producing is much narrower and reduces by the amount you are turning them away. Part of the frame on the sides is likely to be lit by one strobe only whilst you want both rays of light to meet to eliminate shadows
So having strobes pointed forward and changing the arm length is physically the best way to have the largest area illuminated with the least backscatter in front of the lens
Not sure this is clear to you but if you get a piece of paper and Pencil and draw it is quite visual

 

[mjh]

I fall in the two-long-arm camp, especially for lenses like the Tokina 10-17mm, Lumix 8mm, etc... If you look at the "geometry" you give yourself a wider area of "clear water" reducing backscatter. Without a doubt you can do it with short arms and twisting the strobe head but it is more limiting.

Basic Strobe Tutorial: http://opticaloceansales.com/files/OOS-Strobe-Positioning.pdf (soon to be updated)