I also own an FZ-50 and love it in spite of its limitations.
ISO noise is the achilles heel for this camera above 400.
My understanding is if you're using auto ISO it will select a high ISO using the camera as you've stated. Also, manually selecting an ISO higher than 400 will introduce noise.
The "noise reduction" feature of this camera does work at the expense of picture quality due to the old Venus III processor that was used in 2006. It's best to leave the noise reduction option to low and use an ISO 400.
Your exif data shows you used 1/8 sec. exposure so next time try using 1/4 sec. at ISO 400.
The FZ-50 was a knock-out camera in 2006 (and still is for my purposes) but now has 6 year old technology which has been much improved over the years; particularly ISO noise reduction. But I do like the larger sensor it has compared to the newer cameras.
...Just my opinion and thanks for posting.

That last lightning image is excellent and it looks to me like you are quite accomplished at this type of photography. :thumbup: :thumbup:

I love looking at photographs on this forum as it tends to encourage me to try new ideas and this type of image is something I would love to attempt..

Looking at that modified image by jfantasma it appears on my monitor to have taken out the detail of the lightning, turned it very slightly purple and then turned everything else pitch black. Is that the intent or is it my monitor? I ask this as I am very aware of how much detail sometimes gets lost. It is so nice to see others offering different options and top marks to those that contribute :)

As someone that is always learning I am always asking questions and if there is noise then is that due to a lack of light or over working the camera and putting in settings that cannot produce satisfactory results which again will end up with noise? Please note this is the pupil asking questions as that last lightning shot shows me that this person knows their onions :)

That is an amazing shot. I haven't been so lucky. I had some lightning shots that were pretty good but I lost them when my computer crashed. I was pretty dissapointed. I love that shot

Yes I did it all in Lightroom 3.6. I love this program. It is kind of a pain sometimes because if you want to share any of your photos after editing you have to export them to a new album. But on the plus side you can create your watermark for your images as well. Glad I can help now I have bragging rights! LOL just kidding.

In my opinion the ISO settings have a lot to do with your surroundings. If you have a lot of city light I would recommend using a lower ISO and if in darkness you can use a higher ISO setting but I wouldn't go above ISO 400. You just have to take some sample shots with your light set up (or flash).

This is what I came up with. I hope you don't mind that I cropped it a little. I just thought it would look better if it showed mostly the lighning and a little bit of the surroundings. y the way I love the capture. You are fortunate to get this shot.

When you upload a picture click the store original so we can open it up. My guess for your photo is it seems you had the ISO set to high and maybe the distance of the shot. The surroundings are very dark so the camera gets tricked into trying to compensate for the background therefore causing noise. You may be able to get rid of some of it with post processing but I don't know what software you use or the settings of your camera at the time of the shot. It is a good picture though Lightning is extremely hard (at least to me).Try re uploading the picture and clicking store original and I can see if I can adjust it for you.