Questions from a newbie (mostly related to focus)

[kster]

Hello, yesterday I purchased the Canon 100mm f2.8 macro lens and I've been searching this forum for information. This weekend, I'm planning my first attempt at macro. For a class assignment, I'll have the following setup:
- indoor shooting
- natural lighting with a reflector
- using a tripod
- remote shutter release

My subject will be things like plastic jewelry, watches, stones, etc.

A few quick questions:
1. For focusing, should I use the autofocus to get close, keep the shutter half depressed, and then use the focusing ring to nail the focus?

2. If I hand hold the camera, I keep reading about rocking back & forth to get the focus sharp. Why is this done?

3. In natural light, is there a rule of thumb for minimum shutter speed to keep the images sharp?

I'll post some pics after this weekend.

Thanks!!

[lungdoc]

As a fellow beginner with a 100mm I'll try to answer based on my reading/understanding and limited practice - I welcome the views of those with greater experience
1) I think for static objects when really close it's easier to use manual focus and move the camera back and forth slightly to maintain focus. Auto seems to work if you are away from the extreme of closest focus.
2) It's easier to put the camera to the closest focus distance and move slightly then it is to try to move the focus ring when you that close.
3) For a non-moving object the shutter speed minimum would only be there if you are hand-holding, in that case the traditional rule of thumb is a minimum 1/focal length x 1.6 or 1/150, but I'd probably go higher e.g 1/250 as macro likely more sensitive to movement than most. Most people use support e.g. tripod, or a flash in that situation.

[LordV]

Good answers from Mark.
For stationary objects where I'm not using long exposure times I try to work out a way of resting the camera on something rather than swaying, but like many here I always use manual focus (make sure your dioptre setting on the viewfinder is correct :)
Brian V.

[kster]

Thanks for the information guys!

[Cactuspic]

Whenever practical, particularly when I am not using flash as my primary form of lighting, I use a tripod for suport.

Irwin

[kster]

Whenever practical, particularly when I am not using flash as my primary form of lighting, I use a tripod for suport.

Irwin

Good to know. Since I'll only be using natural light this weekend, I'll also be sticking to the tripod (and trying both manual & auto focus).

[John_B]

kster,
I usually set my 100mm f/2.8 to 1:1 (its life size macro focus) and focus by moving the camera, otherwise I could get less then life size which I usually don't want.

[kster]

kster,
I usually set my 100mm f/2.8 to 1:1 (its life size macro focus) and focus by moving the camera, otherwise I could get less then life size which I usually don't want.

I'm at work right now and don't have the lens in front of me. How does one set the lens to 1:1? I thought it was always 1:1.

[John_B]

kster,
When you have the 100mm f/2.8 set at its closest focus point that is when you achieve 1:1 macro (look at the scale on the lens). :)

[kster]

Got it. Thanks John.