Flash not firing, need help!

[melissa_v2]

<p>I did a photoshoot yesterday and got some pretty amazing pics, I think any ways. But.... some of the pics that would have been amazing were underexposed because my flash did not fire. I was using my sb600 flash and was shooting with a Nikon D90 with Tamron 17-50mm 2.8.<br>

I have 2 theories which I don't know if I'm on the right track or completely off. <br>

1) The batteries may have been in need of a change, although the battery light never came on to show that batteries were in need of a change until after my shoot was done. But could it be that even though it didn't show low battery it may have already been dying and my flash wasn't firing? Earlier in the day the flash seemed to be working much better and more consistantly (2:30pm-4:30pm)<br>

2) O.k. I hope this makes sense as I am still an amateur. The second part of the photoshoot took place at around 6:00p.m. So I did open up the aperture to allow for a bit more light and just shot on AP mode. All the while the flash was working sparatically and was giving me overexposed shots so I did fiddle with my exposure button and with the flash, but again the shots were overexposed or under, dependant on if the flash fired or not. Could I have been having problems with the flash because I had opened up the aperture so much and therefore I had a fast shutterspeed, resulting in a flash that wasn't "flashing".<br>

Any suggestions would be helpful and like I said I'm an amateur just looking for some friendly flash advice:)</p>

<p> </p>

[dougscroggins]

<p>Hey Melissa. While I don't proclaim to be anything more than an amateur myself I wanted to tell you that I had the same problem two shoots back. I am using Canon gear and the 580EXII flash but it gave me the same problem in that it wasn't firing every time like it should have. I replaced the batteries and haven't had the problem repeat itself so I'm pretty confident that's all it was on my end. I am not familiar with Nikon gear but I know the D90 is a a great camera and I would imagine your flash and camera have ETTL capability. (I think they call it something else in the Nikon family but it is basically where the camera and flash communicate with one another to make sure the flash knows how much light to put out to get the correct exposure, generally) Under the presumption that your camera and flash are communicating then opening up your aperture should cause the power put out by your flash to be slightly decreased without any further input from you. I will cut out here and leave the Nikonians to help you better. I hope you get it all figured out and hope I've helped, even if only a little.</p>

[dougscroggins]

<p>Hey sorry I missed it the first time but something else you need to realize Melissa. If you are getting good exposures with your setting's on the camera and you open up your aperture by one stop you will naturally notice an increase in the overall exposure unless you change the shutter speed conversely. Assuming that is that you are shooting on manual mode. This may explain why you are getting a change in exposure values when you open up the shutter values. It would also help to know what settings you are using when you are getting problems with your flash not firing. Camera's generally have a maximum flash-sync speed of around 1/250th of a second. With the newer flash systems and camera's you can exceed those speeds but again the two have to be able to communicate and you usually have to change the camera settings so the flash will fire when you go beyond those parameters. </p>

[jpo3136b]

<p>What shutter speed were you using? Many digital cameras will not trigger the flash at speeds faster than 1/180; to the operator, everything may appear at first glance to be normal; but, then sometimes we notice the strobe will not trip. Sometimes, it's the shutter speed. </p>

<p>Have a look at the data for the photos you made, and let us know what the shutter speed was. Perhaps that will help.</p>

[Ray House]

<p>Better yet, post a photo with EXIF intact of one problem photo.</p>

[melissa_v2]

<p>Hi, thanks for all the responses. I'm confident that it was low batteries. I replaced them and had another photoshoot and had no problems at all. I guess even the battery light wasn't flashing that the batteries were low, I should have just changed them up.</p>