Excessive Noise Shooting Trains

I just finished processing a batch of photos from a trip last month and some of the shots seem to have excessive noise in them despite shooting at ISO 200. I know I have issues getting the exposure right since the headlights trick the sensor most of the time and the resulting shot comes out too dark. Is this where the noise is being introduced? Any tips to get a more consistent exposure that is not blown out by the headlights? I've included a link to a shot to show what I am talking about. There was some snow in the air and that always seems to turn out noisy when I shoot as well. Any thoughts here? Equipment/Settings: 50D, 70-200L @f8, ISO 200, 1/160.

https://picasaweb.goog​le.com …60i0Z552Q?feat=​directlink

Thanks!

Shoot in manual and adjust?

The camera only has so much range light-to-dark. In a scene like that, with a moving subject, you will have to choose your exposure manually in advance. Bottom line, if you underexposed the train, you will get noise in the shadows. Play around in your house sometime with the TV on in the dark, and you'll always get noise in the blackness. Remove it with luma noise reduction in post-processing.

The underexposure would certainly add to noise in the images, but what I mostly see there is motion blur; I'm guessing the train is really humming along in those shots.

1/160 us pretty slow for quick moving objects if you're not panning with them. I'd suggest trying to maintain a shutter of 1/400 or better and adjust your aperture/ISO to that allow for that. Then, as long as you are getting a good exposure, the noise ought to be minimal and easily dealt with in PP, if needed.

As has been said, manual will help with that. Try this: Need an exposure crutch?

So then you brighten it up, & that's where some of the noise comes from.

Maybe not a serious noise problem, but this shot of two trains passing just east of Greencastle, Indiana did come out way too dark. This shot was taken with a T2i, Canon 70-300 at 300mm and at ISO 400.

A fairly serious levels adjustment in Elements helped...

your shutter and aperture is what is varying as the train approaches, you are better off establishing a good baseline (you will want a faster shutter for faster trains) and then shooting full manual. If your photos come out dark due too the camera trying to find the right light balance and unintentionally underexposing, then you will get noise when you adjust it brighter.

That image above is very acceptable noise, in fact, I see none...

It looks good to me on my laptop.

Thanks for the advice guys. I really need to trust myself and start shooting in manual. I normally shoot in Av to keep my lenses at f/8, but rely too much on the camera for the rest. Time to step things up. I haven't gotten LR3 yet and the luma reduction in LR2 is pretty basic. I'll have to upgrade and see if I can improve things.

Definitely upgrade; the CA correction and NR functions in 3 are significantly better than in 2.

A 50D should have had no trouble with that BNSF train. But f8 is wrong for that light. Your problem is as you stated -- you set the camera on AV at f8 and let the camera decide the rest. You should have gone f5.6 or 6.3, probably could have set the ISO at 400 with no noise to speak of and the shutter speed at 1/400 at least to stop the train. Work on your composition, too. Picture is leaning CW and the train is centered as well as too far away.