Exposure Problems Nikon 300 f/4 + 1.7X TC

The past few days I've taken my setup out (D300s 300 f/4 + 1.7X TC) I've been having some unnerving exposure problems. 90% of the time things work great, but 10% of the time the photo is either black, or almost all white or is simply too dark/too obviously with the wrong exposure. This happens during single shots as well as during bursts. I'll take a burst of 8 shots with 7 being perfect and 1 being all black or having a very slow SS. When this happens, the camera indicates that the aperture is a Triangle and a 6. Also there is no EXIF data on the really bad shots.

I've checked the contacts and everything looks spotless and like I said it usually works - but the times it hasn't have become extremely frustrating. I've been using this combo for about 4 months and never had a problem until the other day. I'm shooting under bright conditions on moving and stationary objects. Any advice/thoughts are welcome as I'm at a complete loss.

Oh, I also forgot to mention that when it displays the "Triangle 6" for Aperture, the lens will not AF.

Was it extremely cold Luke? It sounds like your shutter may have been sticking. I had this problem with my 40D shooting long bursts, but it was happening when it was about 5 degrees. I never had the problem any other time.

It's actually the warmest it's been in months. Was about 45 degrees today.

Luke,

i wonder if the contacts between the lens and camera may need cleaning. Salt is certainally a camera's puplic enemy # 1.

Mike

I've thought about that but I almost never change my lenses and certainly not in a salty atmosphere. Also, if the contacts are dirty, why is it properly exposing 3 shots, then messing up 1, then getting the next 3 right in a burst? We are talking about SS of 1/2500+! If the contacts were simply 'dirty' I think it would be impossible for this to happen.

- Luke

Not likely to be a lens contact issue. I thrash my gear pretty badly, and shoot almost exclusively on the oregon coast in all types of weather. Its always humid and salty. I've had my fair share of salt water issues, but i think you'd have to try really hard to booger up the contacts before they give you any problems. Its such a simple connection, that I'd say they either work, or they don't.

I recently had similar problems with a lens when the aperture gave out. The whole time I was getting an error message that said my contacts were dirty. I knew that wasn't really the issue. They were clean as a whistle. The symptoms were exactly as you described; very random and sporadic, producing unpredictable exposures. Eventually, the issue became more and more common, until the poor thing finally croaked. The lens is now stuck, permanently on f/16.

Hopefully, you prove me wrong, and its a simple matter of cleaning some gear, instead of a trip to the repair center. In the mean time you might try and narrow down the source of the issue by trying different combos. Does it happen w/o the 1.7TC? Is it only the one lens giving you issues? What happens if you set your aperture to a small size and press the DOF preview? Right before my lens died, I could hear my aperture making a faint grinding sound when I used DOF preview. With a little detective work, you should be able to pinpoint the source of the problem.

Best of luck. Hopefully this helps.

Begin by isolating the problem, is it the lens or the camera. Use other lenses to know this. I had similar problem and found that it was the lens diaphragm sticky. And please update us if you know the problem...that will help.

Thanks for the advice. I'll keep you posted - this whole week is supposed to rain/snow so it won't be until the weekend that I can run some tests. Here's hoping it's nothing serious...

Is this by chance the lens that you dropped in the water a few months back?

Charlie,

nooo no no no no. That was just my 55-200mm... I'd be devestated if I dropped my 300 in! I've since sold my 55-200