SB-700 zoom range

[miguel_martinez4]

<p>I've finally bit the bullet, and got a 70-200 f/4 to complement my family's Nikon cabinet. With this lens, a doubt has jumped into my mind. The specs of my SB-700 speedlight state its zoom range is 24-120mm FX equivalent. Indeed, the speedlight keeps making noises as I zoom in the 70 to 120 mm range on a D700. What does exactly happen outside 120 mm? Do I just lose power? Can I compensate a bit using the centered lighting pattern? Also, does this render the SB-700 essentially useless on my D7k with my new tele?</p>

<p>OK, yes, these are more than one question, but all are related to the working of the speedlight beyond the zoom range. Thanks in advance for all your answers.</p>

[rodeo_joe1]

<p>The 'zoom' range of a speedlight is really the coverage angle of the light from the flash, and it doesn't <em>have</em> to match that of the lens in use. At the 24mm setting the flash illuminates a slightly bigger area than would be in view with a 24mm lens fitted to an FX camera. Similarly at 50mm, 80mm settings etc., up to the minimum coverage angle, which is roughly equivalent to the field of view of a 120mm lens on FX. Beyond that the flash can't narrow its angle anymore, but there will still be the same amount of light put out by it.</p>

<p>In any case it's a bit ambitious to use, say, a 200mm lens and expect the flash and lens coverage to line up exactly. So as the lens used increases in focal length there must be more and more overlap allowed between flash coverage and lens view. Result: There's really not much point in having a flash that 'zooms' to much beyond 120mm, because you gain very little in apparent lighting power. That's excluding the fact that flash used at great distances and with long lenses just looks quite weird and sometimes very ugly.</p>

<p>In short, just use the SB-700 as is and stop worrying about its 'limited' zoom range. You'll never notice a deficiency, even if you do use a lens longer than 120mm. And it's definitely better to have a slightly wider light coverage than one that's too narrow.</p>

<p>"Can I compensate a bit using the centered lighting pattern?" - Probably, but then again it's also probably not worth the bother to change modes.</p>

 

[miguel_martinez4]

<p>Thanks, Rodeo Joe. I really need to up my speedlight mustard. Maybe I should ask for a book these Christmas.</p>