Exposure quandry

[Michael_Hickey]

I am experiancing an interesting problem that apparently is only a factor when shooting with the D1 and not with film

For the first time this year I shot an NCAA volleyball game in our arena with our arena strobes the other night. Shooting with a 400 2.8 provided me with an exposure of 250sec/f10 BUT when I changed my lens to 80-200 or any other shorter lens my exposure seemed to drop and I had to adjust to f6.3. Why would this happen? Of course the light output didn't change and we have pretty much ruled out any mechanical problems, so what gives? My boss said this has always been the case and is not a factor with film cameras.
Anyone have any ideas? [img]images/icons/confused.gif[/img]

[Joey_Chong]

What metering mode where you using? Were the players' wearing white or other brightly colored uniforms? If so then your 400/2.8 would be metering a tighter crop of the person and their uniform. And when you're using the 80-200/2.8 you're probably getting more of the background.


Joey Chong

[Michael_Hickey]

My lens/camera were not metering anything, I am in full manual mode, of course, since I am using external strobes. [img]images/icons/rolleyes.gif[/img]

[DaveLazarowych]

Of course the light output didn't change and we have pretty much ruled out any mechanical problems, so what gives?
Are you saying with this Mike that you've had the lens tested or that the same effect happens on more than one 80-200 or on your 35-70 as well? Have you observed the same effect with the same lens but a different body?

My boss said this has always been the case and is not a factor with film cameras.
What is the point he is making? Is it the same effect on film as well and we just don't see it because the latitude is so great?

[Michael_Hickey]

Yes this has happened on other lenses as well 80-200, 35-70, 28-70 all show a different exposure than the 400 2.8 which by the way just came back from service from Nikon, and the shorter lenses are all brand new except for the 35-70.
Not confirmed by me but my boss says that film cameras do not have this quirk it is only an issue on the D1 which makes me think definately it's not the lenses but the D1. As far as the latitude issue goes, I'll have to look into that one, could be worth investigating that's for sure.
This was my first time shooting with these strobes so I have a lot of testing to do, I was just looking for some possible avenues to explore.

[Thom_Hogan]

What kind of 400mm f/2.8? AF-S, AF-I, or is it one of the older MF versions? Teleconverter or not? Are you mounting the lens or the camera on the tripod?

Assuming that you're not using a teleconverter and it's an AF-S lens, I'd be suspicious of the camera/lens contacts at the top of the mount. I've seen isolated cases of the spring-loaded contacts not working correctly.

Thom Hogan
author, Nikon Field Guide
author, Nikon Flash Guide
author, Complete Guide to the Nikon D1, D1h, & D1x www.bythom.com

[Michael_Hickey]

Yes as a matter of fact it is an AF-S. Not the current version but the original. I will look at those contacts that sounds interesting.
Thanks so much. Sounds like my best lead.
MH