Micro / Macro question?

I need to photograph small objects at a distance of 2-4 inches (5-10 cm) from
the lens. I want a magnification of ~50 to 100.

Photomicrography (using microscopes) is limited in the working distance from
the objective; it needs to be <1 inch. Photomacrography is limited in the
magnification; typically <10.

I'd like a solution that terminates with filter threads (any size can be
adapted) so I may attach a digicam.

Suggestions?

If there is a better forum in which to ask this question, just point the
way...

Thanks.

 

Hi Doc,

Seems like your solution would be an 'industrial' type microscope, not the
ones used in medicine. These usually go to the magnification and the working
distances you need. The better ones will zoom and have a ring-type
illuminator. A camera will usually attach with a 'C' mount. If you want to
use a P&S camera, make sure that a 'C' mount can be attached to it.
A stereo microscope with a camera tube will let you view the image through
the right lens, while using the left one for the camera. Fancier ones will
even have a third objective lens, allowing taking photographs while having
full stereo vision. Hope this helps.

 

You are mixing a lot of different technologies.

Let's try again.

What is the size of the object to be photographed? Is it two
dimensional? Is it important to keep the entire depth in focus? How much
depth is there? Is the surface shiny or flat? Is there a lot of detail?
What type of camera are you using or do you have available? Digital?
Lenses? Lighting? Does the subject move? How will the results be viewed?
In a book, a large print as video etc.

 

Sorry I hit send too soon. It is not clear if you know or are asking
about Macro vs Micro. In the traditional sense Macro is anything recorded
on the light sensitive material at life size or smaller to about half to
quarter life size. Micro is used for anything recorded larger than life
size. Those terms don't have a lot of meaning in the digital world with
the changes in sensor size, but from a technical view, I would guess they
still apply.

 

I think what you're looking for is a stereo or stereo zoom microscope.
It's sometimes called a dissecting microscope. You'll also need an
eyepiece adapter for your camera ... or buy an eyepiece camera.

What are you trying to photograph?


TR

 

What is the size of the object to be photographed?

~50 micron

They are roughly spherical in shape.

Not sure. Not important. Suspended, submerged in clear water, so of high
contrast.

No. Confirming presence and number will be sufficient.

Have Canon P&S A95 digital.

researchers.

 

1 millimeter = 1,000 microns so if they were closely spaced, 100 of them
could be counted in a screen sized mm wide strip (ballpark scope).

7.18 x 5.32 mm sensor so the 1mm wide frame would be about 7x.... but
that's not how things are stated in photography, the "7x" in camera
speak is a completely different number, anyways it would be a job for a
microscope mounted camera.

The Nikon Multiphot system
http://www.microscopyu.com/museum/multiphot.html
.... goes up to 40x which means a 24x36mm sensor capturing 40x life size.
1/40th of 36mm is .9mm... round that off to 1mm so that would work for
your purposes with a DSLR, but you don't need to make huge beautiful
prints at that size so probably something much less powerful is needed.

Re-reading your original question....

Hmmm, so you need a longer focal length to keep further from the
subject. That is odd because extreme closeups are usually done with
short focal length lenses, like the Multiphot above uses 19mm at 1:40
and 120mm at 1:1. To use longer focal lengths would require a very long
tall bellows.

 

Hmmm, so you need a longer focal length to keep further from the

But since the subjects are submerged, longer working distance is necessary.

For example...? Can you give me an idea of what lens (backward?) and what
bellow length? Just a ball park idea...

 

From "The Science of Imaging: An Introduction" by Graham
Saxby,

Photomacrography is the making of an image that is larger
than the object using conventional camera technques.

Photomicrography is te technique of imaging through a
microscope.

Generally though, macro has become more broad in meaning and is
now commonly used for 1:4 ratios on zoom lenses rather than only
at 1:1 or more.

But the basic difference is the use of a compound
microscope (micro) rather than a generic camera lense
(macro).

 

You want to look at a web cam mounted on a dissecting
scope. That combination will give you the lense to
subject distance you need and allow both optical and
through the camera viewing (and you will soon enough
determine that optical viewing is great for the initial
setup, while through the camera viewing is essential for
photography).

This web site has a large selection of articles
describing virtually all aspects of photomicrography.
For you purposes be sure to read the ones involving
dissecting microscopes, but for a general overview
you'll want at least scan through some of the others
too.

http://www.microscopy-uk.org.uk/mag/libindex3.html

To get the magnification you need, that is not within
reason.

 

http://www.microscopy-uk.org.uk/mag/libindex3.html

Thank you.

 

I think it's a microscope job but I'll try to make an educated guess for
an SLR setup. A regular 200mm lens needs about 200mm of
extension/bellows to reach 1:1 and a typical bellows is about 200mm, so,
I'm not sure, say you start with a 200mm macro lens already at 1:1,
another 200mm of extension brings it to 1:2 which is still a 12mm wide
field of view and you want to see about a 1mm frame. Well, if that's a
10MP image, 3,000 pixels across & 3 pixels is enough to resolve an
object & you can crop to 750 pixels wide field of view of 3mm... not
rteally enough detail. I'm not sure the working distance of this setup
but would guess at least 4 inches. The Canon 65mm MPE goes to 1:5 and
probably has a working distance considerably less than 2 inches so maybe
an in between focal length, 100mm macro lenses are common but I think
you'd need something designed for more magnification: something more
like a microscope lens, not a 35mm still lens:

Here's that Multiphot setup with what looks to be about 400mm of
extension (twice the size of a normal bellows):
http://www.naturfotograf.com/images/U020812490.jpg
Here's the lenses which go with it:
http://www.naturfotograf.com/lens_spec.html

 

Hi there,

If it can be done, then the people at Brunel Microscopes will know:
http://www.brunelmicroscopes.co.uk/

I have several of their IMXZ 'scopes with digital cameras for field of views
ranging from 50mm diameter down to around 1mm. At 1mm you will easily be
able to count/detect 50um particles.

A