How do I use bellows?

Managed to track down a set of Pentax bellows for the LX - probably the last 'useful' accessory I'll need .

Just a couple of questions:

How are bellows best employed? What lens works best with them? - I have a 50mm and a 28mm (I'm guessing the 500mm mirror and the 28-200mm zoom won't be suitable ). Should the lens be reversed or the "right" way round?

Advice please

http://www.bdimitrov.de/kmp/lenses/primes/short-tele/K100f4-Bellows.html

G

All a bellows does is place the lens further from the sensor plane, which means you can focus closer. Because of this, the lens doesn't have to be able to focus, which is why a bellows lens lacks a focus ring.

Usually you would mount the lens the same way as normal, and a longer focal length will allow you to place the subject further away. Useful if it's a poisonous spider.

G

Thanks for the info George, but due to my arachnophobia, I won't be taking any spider pictures

Another thing to consider is the resolving power of the lens. The more extension you put behind the lens, the more you make the lens work. The quality of a standard 50mm lens will start to degrade at about 1:1 which is why it is often recommended that you reverse the lens above certain magnifications. Doing this you lose camera control over the aperture but you will not lose as much quality because conventional lenses are designed to work best at infinity so they focus a distant point on a relatively close film plane so when you reverse it you are getting it to do more like what it was intended for. It is possible to use a macro lens at higher magnifications the right way round because they are corrected to work in that way. I have used a 100mm macro lens on a bellows for magnifications up to 4:1 with some success but that is about the limit.

Carl

Reversed or not, aperture control is always manual when you use a bellows. Even the Pentax Bellows-A set lacks the electrical contacts required to convey lens info to the body. You'll also need two cable releases. I guess you got the double one which comes with the bellows. That'll work OK for a film body. I use a single cable release on the lens end of the bellows and a seperate one for the camera (K10D).

Note: The bellows can't easily be fitted to a *istD/DS/DL digital body without first attaching a short extension tube between camera and bellows. No such problem with the K10D or film bodies.