Focus versus Rail stacking Poll

deanimator wrote:

RobinHsherwood wrote:

xpatUSA wrote:

deanimator wrote:

xpatUSA wrote:

c h u n k wrote:

xpatUSA wrote:

deanimator wrote:

I use microscope objectives, so I don't have a choice. I HAVE to use a focus rail, in my case a Wemacro.

Thanks, I wasn't familiar with that genre. I should have made it clearer that I'm talking about simple objects like flowers, bugs, small artifacts, etc.

Many people use objectives for all of those subjects.

Pardon my ignorance but I don't understands "objectives". Are they the so-called close-up filters or the likes of the Raynoxes?

Neither. Google a picture of a microscope. Those cylinders protruding from the turret of he microscope are lens assemblies called "objectives". As a general rule, they have neither integral focus nor aperture mechanisms.

I see. So the "Many people" who "use objectives for all of those subjects" have gone out and bought fancy microscopes to shoot "flowers, bugs, small artifacts, etc".

I can't say that there is no 100:1 macro lens. I can say I've never heard of one. That's strictly the domain of microscope objectives... and electron microscopes.

I sense deliberate obfuscation, please desist ...

Ted,

It's NOT obfuscation, but an attempt to supply valuable information.

The many people mentioned do not buy fancy microscopes, but instead use one type of microscope objective directly mounted upon either extension tubes or bellows as shown below;

A 4X microscope objective mounted on extension tubes.

A 4X microscope objective mounted on bellows.

Another type of microscope objective requires the use of a 'tube lens' in order to focus the image, these tube lenses are usually medium telephoto (100-200 mm). Shown below is a 4X microscope lens of this infinite type, mounted on my 100 mm Macro lens.

A 4X infinite type microscope objective mounted on a 100 mm Macro lens.

I hope these illustrations provide some clarity to the discussion. If you require more information about this fascinating area of macro photography, please just ask.

How well does the infinite objective do with the 100mm macro lens as the tube lens? I've heard conflicting recommendations for and against.

It vignettes at the infinity setting but works very well when focused at 1:1. However, this photo was taken while testing various options, I don't use the 4X infinity corrected Amscope objective on this lens. The 10X infinity corrected Amscope works very well when the macro lens is focused at infinity giving about 5X mag, when focused at 1:1 it gives 10X. I use the 4X inf lens on an old Minolta 100-300 mm APO zoom at 200 mm, it's brilliant! The 4X illustrated on tubes & bellows is an old Leitz finite PLAN designed for 170 mm tube length it gives over 6X at full bellows ext.  Still testing other finite PLAN lenses from my Leitz Orthoplan microscope.