i took up experimenting last year with long exposure photography,if you look at the photo of Tower Bridge,this was a 4 second exposure,i have done long exposures as low as 3 seconds and up to about 30 seconds :). Any way the camera i used at the time was a Nikon D3300 and Nikor 18-55mm + Tripod along with one of these shutter release gadgets, as of now i've moved from a crop sensor and on to a full frame camera ( 5D mK11). The mk11 is slightly heavier than my other camera and i want to try out long exposure with it would the tripod i used on the D3300 along with another tripod be able to support the weight with say a 150-600mm lens attached to the camera
It's good that you're experimenting with something new. Long exposure photography is one of my main focuses.
Do you have any more recent photos of your long exposure work? I'd be willing to give some advice, but since this one is old, I don't want to give tips that you may already be using.