Thread: Not much depth of field...

Can you not adjust DOF a bit with aperture.

I'm glad you said what it was as it looks like a ...


Nice and sharp. What lens did you use with it and how long an extension?

This is my el-cheepo sony 18-70 kit lens. It might have been sharper if I'd used the other lens, but I'm quite impressed with this one. To keep my life simple the 2.8 is on the camera and the kit lens now has the tubes permanently attached.

Took me a while to get it focussed though. I bluetacked the bean to a translucent tupperware pot which you can see in the background. This was on a white bench top and the tripod set to bench height. I found it easier to move the bean to focus than it was to adjust the camera.

I used all three tubes in the set 7, 14 and 25mm (I think) for a total lenght of 46mm. This was with about 35mm on the zoom lens. I had to take the filter off the lens to allow the bean to get closer to the front element at one stage!

Cheers, Steve

Originally Posted by Mick-Kelly

Can you not adjust DOF a bit with aperture.

Due to the el-cheapo contactless tubes the aperture control is manual. I had it about half way closed. Any more and the viewfinder was too dark to focus with.

I guess I could have gone for fully closed and used the screen to focus. But given the effective light loss in the tubes the exposures were long enough. A coffee bean doesn't move much, but if it was a flower or insect there would likely have been some movement if I'd ended up with a 10 second exposure. I think this was about half a second.

Cheers, Steve

Open the aperture right up so you can set up the shot, get the focus right, then step the aperture back to where it needs to be. Even so the aperture is going to be razor thin.

I bought Kenko tubes for the reason they have the contacts for the lens. I thought it was worth the extra it cost me.

Why didn't I think of that...

I just wonder if a diopter will not give better results that this image with cheap extension tube.......

The tubes were an impulse buy (I was shopping for a hot shoe spirit level) so I didn't research much.

Would a dioptre give this level of magnification?

Cheers, Steve