[Rocket]

In general the larger the mm number the further you can get from the insect and maintain the same size image. It is the same as using your zoom lens. Set your zoom to say 100mm and fill the frame with an object, then set the zoom to say 200mm. You will have to walk backwards until the object will fit in the frame again.

So 90mm you can stand further away than 30mm.

And yes, most macro lenses are a fixed focal length.

I'd say 30mm is to short a focal length for insects - you have to get so close they fly off.

90 or 100mm is a good bet


I sometimes use an extension tube with a 55-210 zoom lens to enable me to get shots higher up in bushes. You can shoot a butterfly a few metres away like that.