Focus when doing Macro?

Got an old K mount 50mm F4 Pentax macro lens through this morning and am having a play but there seems a very narrow field of focus with it. I know this is not a 1:1 macro lens (Not sure if this makes any difference) but the main subject is not all in focus, on the spider shot the aphid is out and on the beetle half the body is out.
What am doing wrong?

Thanks.

It's not that you're doing anything wrong, nor is there anything wrong with the lens. Depth of field gets progressively narrower the closer you get to the subject; as macro lenses get very close indeed they have wafer-thin DOF's - this is why macro shots are often taken at very small apertures (I use f8~f22 typically) which can mean using a flash even in broad daylight.

There is a definite art to taking macro pictures, you just need a little practice and you'll be up there with Clarky and Dan!

there's an art to picking where you put your plane of focus too, for example the beatle above would probably look a lot better if the focus was a little closer. I would have aimed to get his close eye and wing as sharp as possible. A lot of the shot would still be outside the DOF, but it probably wouldn't notice so much.

This is why many people say that AF is not very useful in a macro lens, you'll end up manually changing it most of the time anyway.

Nearly all my macro photo's are taken at F/16, manual focus and aim to get the eyes in focus, the rest usually then falls into place. But the attrition rate can be high, especially at 1:1 or greater with the wafer thin DOF.

It would make a difference - depth of field at 1:1 is even less!

It looks to me that you've used the lens wide open, or near enough. Stopping down to f/11 or 16 will give you more depth of field, but at the expense of a slower shutter speed. You may still be able to handhold in bright light, especially if you up the ISO to 200.

Focusing is critical, and when you get that right, you can get away with using a wider aperture (one of my favourite shots was a dragonfly side-on, taken at f/5.6, at 1:1 mag - part of the eye is in focus, and some of the rest of the shot, but it just looks 'right' to me).

You need to carefully choose the angle you're shooting from. The beetle would have been better more from the front, looking at it at an angle still. You would have been able to get its nearest eye, mouth, and front of shell in focus (or near enough). Just try different things, and see how you get on.

Fundamentally though, you're doing nothing wrong!

Dan

Not much more to add from all that great advice. But get your self a flash and a diffuser for it. Or better still make yourself a macro flash like i did.

Oh and make sure you know the names of the bugs and spiders you post or else Dan will yell at you

That's true.

Dan

Ok, cheers for all the info.
Got my 90mm Vivitar Macro M42 this morning and focusing is a REAL pain on that.
Heres one I did earlier..

No cropping at all.




Cropped 65%





I must admit the colours on the Vivitar lens seem so much better than the Pentax though ..