Stobe light problems

[jillian]

Hello-
I just moved from using hot lights to using strobes.
I got a pair of strobes and a dynalite power pack- used. The light is great and i am *finally* able to capture motion. But there are little grey spots showing up all over the photos. The weird thing is that they seem to be in the exact same place every time. I took some photos not using the strobes to make sure it wanst my camera- and sure enough they were gone.
Does anyone have a clue as to what is going on? It seems like it has something to do with the lights.
I am using a canon EOSrebel with a hot shoe adapter to allow me to hook up a sync cord to the power pack. Maybe there is some weird power surge happening with the pack to the camera? I bought the cheap hot shoe adapter. (maybe that was a bad idea.... again)

did i just answer my own question?
does anyone have any similar experiences ?

thanx
jillian

[RichardtheSane]

Sounds like sensor dust. Are you using smaller apertures now you are using the strobes?

Heres something to try.

With any lens and camera in AV set your aperture to F22 or higher and ISO. Find something light coloured (sky is always a good thing assuming it is daytime :) ) and shoot a frame off.
Don't worry about a longer shutter speed because you are not looking to get a perfect shot and for this motion blur makes no difference

Once you have an exposure download it and check to see if the spots are there. If so then you have got sensor dust. Sensor dust becomes more aparrent in images that are shot with smaller apertures, so F22 will bring it right out!

[jillian]

That would make sence that it is inside the camera, as the spots were always in the same place.

i see that you can clean the sensor yourself.... looks a little scary! But not too bad i guess.


Thanx for the advice!
jillian

[RichardtheSane]

No worries :)

Sensor cleaning is easy as long as you get good equipment and make sure you use either a fully charged battery or an AC adaptor.

(Personally I trust the fully charged battery route more as power cuts do happen...)