Depth of Field

[JohnR]

I can't seem to get the hang of depth of field. I tried this shot with a 180mm macro and couldn't get the whole of the beast in focus even though I went to f32, I switched to a 60mm macro lens and eventually got this at f8 1/15th and even then it's not all in focus. I had to set the lens in the same plane as the moth to even get this close.

Has anybody got any idea as to what I am doing wrong - apart from failing to understand depth and lenses. This is the best of over 100 shots.

Brindled Beauty

[Rogerdodge]

John
The first thing to check is that it really is shallow depth of field you are experiencing, and not some other blur (e.g camera shake).

If it is camera shake, then no part of the picture will be sharp.

If it is shallow depth of field, then at least some part of the picture will be really sharp.

The depth of field varies with the aperture, length of lens, object (image) size and subject to camera distance.
For a given image size - for example, your subject fills half the frame - the focal length is irrelevant, and the effect of aperture will be identical.

In order to get best depth of field you stop down to f22, but sacrifice some sharpness, and reduce the shutter speed to a level where even a tripod mounted camera may show some camera shake (shutter bounce for example).

Best to get to f8 or f11 and get the subject as near to parallel to the film plane as possible.

You can also increase depth of field by having a smaller image, and cropping to increase its size, or move to a camera with a smaller sensor (same thing really).

Remember that a smaller image, artistically placed in the frame will give a much more pleasing photograph than an "in your face" close-up.
See Neil Hulme (Sussex Kipper) for some excellent examples of this.

For example, at f11 your Dof (180mm) on a 1.6 crop camera will be 1cm at 1m, move in to 50cm, and the DoF becomes just 2mm.

HTH

[Gruditch]

In other words John, step back a bit.

Regards Gruditch

[Rogerdodge]

Gary
Sheer genius
You managed to condense my verbosity into four, succinct, words.
Superb

[JohnR]

The 60mm lens was at its extreme focus, there was a wind moving the birch, the tripod seemed stable and I was using a cable release on the camera.

In other words John, step back a bit.
Regards Gruditch

I dooooon't think a longer cable release would work, suppose I could get a wireless one I had already tried the 180mm with and without the extender, from fully open to fully closed and with the ISO from 100 to 2000 the noise was noticeable from about 1000

IMG_1067 reduced.jpg (52.86 KiB) Viewed 492 times

[NickB]

Looking at the way the moth is positioned (wrapped slightly round the tree) and the slight angle you are shooting from I think the right wing-tips are slightly outside the d-o-f available. As Roger says - take one step back and recompose; that way you increase the chance for a sharper subject.
Also, speaking of "sharpness", I would suggest that for the sharpest detail using a 180mm macro, I would aim to shoot at f11 - f13. I know that f20+ works well for landscapes and does capture more detail, but using a macro lens, sharpness also depends on f-stop. (I refer to the presentations at a UKB Photography Workshop (can't remember which one !) where it was shown that the sharpest image for a 100mm macro lens was around f8-f9, if I remember correctly; outside that range the image was much fuzzier. I use a 200mm macro and have found that the "sweet-spot" for maximum sharpness and d-o-f is f14). If shooting at a high enough speed is an issue, to reduce the chance of motion or camera-blur (for a 180mm the lowest I would go is 1/160th - 1/200th) then using ISO 400 or 800 should remove that problem. (Dare I mention fill-in flash...? I think attending the Photography Workshop, where people can give you first-hand advice and examples is one of the best things anyone who is thinking of starting down this route can do)

Taking pictures of things that lurk in dark places is always going to be a challenge
(Some moths also have a nasty habit of vibrating, just to make it harder too!)
Good luck
N

[Rogerdodge]

Nick

Some moths also have a nasty habit of vibrating, just to make it harder too

Indeed they do.
I have found that the only way to "freeze" some moths is to use flash. To my mind, flash and moths seems to work, in that the black background is acceptable for a creature of the night.
Again it is important to use a really diffuse "bounced" flash. I have found that scrunched up tissue paper over a flash head, and then bounced from card etc. is pretty good at removing the harsh shadows of unbounced flash.

[Pete Eeles]

Nick

Some moths also have a nasty habit of vibrating, just to make it harder too

Indeed they do.
I have found that the only way to "freeze" some moths is to use flash. To my mind, flash and moths seems to work, in that the black background is acceptable for a creature of the night.

I find the best combination is flash, with a fairly slow shutter speed. That way you can freeze any motion *and* get some ambient light included to avoid a black background.

Cheers,

- Pete

[JohnR]

Thanks, I'll dig the 180 macro out of the dustbin and try again and maybe stick to non-vibrating butterflies.

[NickB]

Worth persevering, John!
I think this is one of the better explanations available on the web for d-o-f (I think JackHarr posted this before...)
http://www.cambridgeincolour.com/tutori ... -field.htm
Even I eventually got my head round it