DSLR And Reversed Lens As Microscope

Abstract: This article demonstrates how to use a DSLR camera with a reversed lens for taking high level magnification images and as a simple yet powerful microscope.

Author: Sparq. This article is under construction but feel free to send me comments via PM in the SRP forum.

Goal

The goal of this article is to show you how to take pictures like the ones in this page with your photo equipment for cheap. The "trick" discussed here is use of reversed wide angle primes on DSLR bodies.

Prerequisites:

1. A DSLR camera of any brand or vintage that allows for manual focus lenses

1. A wide-ish prime lens for a 35mm camera with manual aperture control

1. An adapter for reverse mounting of your lens to your DSLR body

1. A tripod

1. A well lit surface for placing your razor such as a kitchen counter top

1. Patience

Camera

Any DSLR camera with a support for manual focus lenses should work as long as you can get a reverse mounting adapter for it. I use a 4/3rds Panasonic DMC-L1 but most (if not all) DSLRs should work (except for those dumbed-down by their manufacturer to force you to use their expensive auto focus lenses). I highly recommend cameras with Live view as they make focusing easy and that can also work as high magnification microscopes.

Lens

High magnification macro pictures can be taken with reverse mounted fixed focal length lenses. The general rule of thumb is: the shorter the focal length of the lens is, the higher the magnification but also the narrower the depth of field. Usable focal length range is typically between 20-50mm (in 35mm format terms). The lens should have a manual aperture control as it can not be electrically linked to a camera. Note that as the mounting is done via the lens's filter thread, it does not have to be from the same manufacturer as the camera. 

I use a f=29mm vintage Exakta lens (Meyer Görlitz Orestegon 2.8/29) on a 4/3rds body. This combination yields magnification demonstrated below.

Adapter 

Adapters for reverse mounting of lenses are readily available on 'bay for less than $10 (see http://shop.ebay.com/i.html?_nkw=reverse+lens+adapter). They mount lenses via their front filter thread so make sure you have a match against your camera body AND against the filter size of your lens.

I use a combination of two adapters - a filter thread to Exakta body adapter and an Exakta lens to 4/3rds body adapter to mount the Orestor on L1.

Tripod

A solid tripod is a must. You can use anything that lets you place the camera near a counter top or any other well surface where the razors will be placed.

I use an olden but golden Tiltall tripod whose central column and three-section-legs makes it easy to place the camera close to a counter top edge.

Well lit surface

Anything goes as long as the place is well lit and the razor is safe. I recommend you to pick a place that is well lit by a fixed light source as variations in lighting will make it impossible to compare a series of pictures. With fixed light, your changes of repeating the exact lighting conditions may be higher.

Taking Pictures

Here is an example just for your entertainment and inspiration. You are certainly a skilled photographer and so you will figure out a better method quickly. :)

Mount the lens to the camera via the reverse adaptor. Switch your camera to a mode that allows use of manual focus lenses and switch on the live view if available. Place the camera on a tripod and place it near the counter top. Place a sheet of newspaper on the counter top and play with the tripod and the camera (position, angles, distance) until you get a straight and well focused picture of the newspaper in the viewfinder or on the LCD. Place the razor edge near the center of focus and re-adjust the camera and razor positions until you get a well focused image of the edge. Mind how the razor's edge is lit. You will have to focus with distance - with moving the edge forth and back. It can be confusing initially but one gets used to it quickly. When well focused, take the picture but make sure you do not shake or move the camera (remote shutter release or self-time use is HIGHLY recommended). Feel free to experiment with apertures, the smaller the aperture the larger the DOF but also the longer the exposure.

When everything goes as planned, you should be getting pictures like those in this page or better.

Post-processing

In order to achieve maximum sharpness, I recommend shooting raw files and post-processing them in your favorite editor. I have been using Picture Window Pro with excellent results for years (inexpensive, works with 16bpc, can process very very very large files (i.e. large scans of 8x10 negatives) and does not require big hardware).

Using Camera as a Microscope

In order to be able to see the magnified picture on the camera LCD instead of in the viewfinder, the camera needs to have Live view. Switch it on and use the "digital zoom" for highest magnification (if your camera is equipped with one). It works very well on my DMC-L1.

Troubleshooting

Under construction

Geometry, calculations, magnification

Under constructions. Volunteers are welcome.

Discussion, comments

Please add your comments, complaints, experience and links to your pictures here.

Cheers, Sparq.