Larger than 1:1

Hi,

we need to photograph really tiiiny objects, at the size of approximately 3x3x3mm.

Using a 120mm Macro Sinaron on a p2 with Sinarback 54 we don't get enough depth of field, as we get into somewhat 10:1. Stopping down to f/64 results in a mushy picture (diffraction).

We don't mind to use a Mamiya RZ with the Sinarback or even a Canon 5D MkII instead.

Any suggestions?

tobibu

Have you tried focus stacking?

I agree, it sounds like a job for focus stacking.

Also, are you scheimpfluging to decrease the amount of DOF you need?
--
~K

Focus stacking! Focus stacking using a macro is amazing and easy with CS5, but there are other programs. The Scheimpflug technique also works, but is a lot touchier.

well... the scheimpflug doesn't help that much, as the object is more or less a dice, and therefore as high as deep...

But we'll definately try the focus stacking...

Greets

tobibu

Once you go past about 2:1 (2X) the rules change. Bigger (film/area) is not always better. Often the inherently better DOF in a small film/sensor system is a much larger advantage that the large format advantage. So, for a 3x3x3mm item "I" would use a FF or APS sized digital camera (not a Sinar 4x5).

Also, common "macro" lenses are optimized for around 1:1 and begin to degrade as magnification increases. Consider putting something like a high quality 60mm to 100mm enlarging lens REVERSE mounted onto a macro bellows for this type of work.... I "think" mine is a 63mm Nikor enlarging lens. Think about it, enlarging lenses are optimized for something small at their back element (film) and something large at their front element (print).

Focus stacking is also something to look at: at this magnification it will require a GOOD tripod and good macro stage.

Hope that helps.
--
Tom Ferguson
http://www.ferguson-photo-design.com

You should read through the forums at photomacrography.net. I would suggest a T-mount adapter with a 4x microscope objective, bellows, and normal DSLR. With focus stacking.

tobibu said:

we need to photograph really tiiiny objects, at the size of approximately 3x3x3mm. Using a 120mm Macro Sinaron on a p2 with Sinarback 54 we don't get enough depth of field, as we get into somewhat 10:1. Stopping down to f/64 results in a mushy picture (diffraction).

Click to expand...

Focus stacking is definitely the answer here...even a PC-E T/S lens won't get anywhere near the extended DOF results stacking does.

I shoot a lot of very small macro flower stacks...some are almost as small as your 3x3x3mm size.

This tiny "Crown of Thorns" floral is only about 7mm across the entire frame.
http://kvincentphotography.ca/stackedimages/h1fdc3e77#h1fdc3e77

and, this 20 stack Passion Macro shows detail & DOF no regualr lens can provide.
http://kvincentphotography.ca/stackedimages/h1fdc3e77#h137fba94

Here's my short web article on stacking if you feel like a quick read.
http://geofflawrence.com/blog/?p=3367

Please note, if you are going beyond macro 1:1 ratio...even with stacking you will need to shoot at approx f/16...at less than 1mm intervals along the rail in order to adequately cover the desired subject focus range.

KEV
--
http://kvincentphotography.ca/stackedimages
http://kvincentphotography.ca/designerflorals
http://kvincentphotography.ca/macro