What do rails do?
 

Ok, I am dumb, I've seen the DSLR rigs and understand the follow focus/matteboxes and handheld set-ups, but I still don't understand what rails do?

Please enlighten me !

Rails let you mount stuff quickly and easily to the camera. The most important items are the follow focus and matte box. Because lenses have different lengths, the position of these items will change from lens to lens. Rails let you slide the FF and MB as needed.

Rails also provide support for those attachments. A lens itself can be quite heavy, but a matte box with filters and a follow focus might be too much weight for the camera body's lens mount to safely bear on its own.

Also, very, very few follow focus systems are able to mount without rails. How else would you mount the follow focus?

thanks for your answers!

I spent my money on lenses right off the bat, thinking my Manfrotto video tripods would work for the DSLR.

I haven't yet invested in a follow focus system or a viewfinder as of yet. I really need to do that.

The manfrotto video baseplate, is not optimal it seems for my 7d nor for the 70-200mm lens, is there another way of attaching it to my tripod sans rails? I will invest in rails before too long but right now, it's out of my budget.

thanks again

Chris,

It really depends on how you want to shoot. If a tripod is the key, go for that first. You can attach a lever for focusing, and you can use screw-on filters and a still camera hood, instead of a matte box.

On the other hand, maybe you want to do well-controlled handheld shots. In that case, get a viewfinder and some sort of shoulder rig. I built my own for well under $100.

Here's a nice setup without rails:
http://www.dvinfo.net/forum/canon-eo...lr-rig-me.html

Another option is a slider. It's best for viewing small objects. You don't really need any other attachments for a slider.

Then there are jibs and dollies. A monitor is probably the most important attachment. To do it right, you need a remote follow focus.

At the top of the food chain is a Steadicam. A monitor and wireless follow focus are needed to make it complete.

Anyway, a tripod or shoulder rig is the place to start. Rails are nice, but first thing first.