12.30.2010

Adding a lens adapter to a point and shoot camera - Canon G9

From time to time I have enjoyed playing around with filters on point and shoot cameras. Typically this can only be done on the higher end models, such as the Canon G series and Panasonic LX series. Also, some of the all-in-one superzooms, such as the Panasonic FZ8 also allow for the use of filters. To get the job done, a special tube attachment called a lens adapter is usually required, and the camera must have threads at the base of the lens unit, designed to accommodate such an attachment.

With dSLR lenses, it is pretty simple to add a filter to a lens. That is because interchangeable lenses nearly always have threads on the outer end. For example, a typical kit zoom lens might take a 58mm diameter filter. Filters of similar size can then be screwed into the lens threads. If you only have, say, 62mm diameter filters, these too can fit, by adding a "step up" ring (sized at "58-to-62"). These thin metal rings can be purchased from all the online vendors or from ebay, often for under $5, and are placed between the lens and the filter.  In this case, one side of the ring has 58mm threads to screw into the end of the lens, and the other side is tapped to receive the 62mm threads of the filter.

Reverse-mount rings can also be used. These allow a photographer to reverse a second lens and attach it to the end of the camera lens, in nose-to-nose fashion.  Sometimes two lenses are better than one! For example, using the same 58mm diameter dSLR kit lens mentioned above I can reverse mount an old 50mm f1.4 Nikon lens that has 52mm threads by using a "58-52" reverse mount ring. With a reverse mount ring, both sides have threads. The resulting setup can result in extraordinary macro capabilities.

This all works easily on dSLRs; but compact cameras present problems. Usually the lens retracts inside the body and a protective cover automatically slips over the lens. Using a filter would interfere with this action. And most of the time the lens has no filter threads.

To solve these problems, some of the higher end compact cameras are designed to use a special tube attachment, called a lens adapter. These are designed to be as small as possible but large enough so the zoom lens can operate within the area provided by the tube. The filter or supplemental lens is then threaded onto the end of the tube where it remains stationary while the zoom moves in and out.

In addition to using filters, supplemental lenses are available, which when added can provide one of the following: wider angle of view, a more zoomed in field of view, or better macro capability. For me, the most common use of the lens adapter is for a Canon 500D closeup lens. Though it looks like a filter, it is in fact an acromatic lens about the thickness of two filters and made with two pieces of high quality glass fused together and designed to minimize distortion. The Canon 500D lens can be used on any camera, and it comes in several diameters.

The 500D closeup lens is designed to provide focus at 20 inches (i.e. 500mm distance). Once your subject is in focus, you can frame the image by zooming in or out; however, the focusing distance will remain at 20".

Below are examples using a Canon G9 camera with a Lensmate 58mm adapter:

G9 with lens extended after powering up, without lens adapter


G9 with lens adapter attached. This one is made by lensmateonline.com. It is a high quality aluminum fitting.


G9 with lens adapter and D500 Canon closeup lens. No step up ring was required because both fittings are 58mm.


This gives you an idea of the closeup capability, with lens fully zoomed at 210mm focal length. Working distance was measured at a comfortable-to-work-at 20 inches. At this distance and zoom length, you can focus on a subject as small as 3.5". This is perfect for butterflies, dragonflies and flowers.


Amazingly, I found if the G9 is switched to macro mode with the D500, it will focus at any distance between 10" and 20", making this a very versatile set up. I always use autofocus. At 10" you can capture a 2" wide subject, which is nearly equivalent to a 1:1 macro.


G9 and Nikon 50mm standard lens can be reverse mounted for macros.  I am holding a reverse-mount ring, threaded with 58mm and 52mm diameter threads.


G9 with Nikon 50mm lens reverse mounted.


With this reverse mounted setup, I can fill the frame with a subject that is 3/8" wide! But note that depth of field is minimal. I focused on the center of the image, right on the "dot" that the "2" starts with. Everything closer and further away is blurred due to the shallow depth of field.  This in unavoidable at such magnification.

12.19.2010

Club print "salon" entries for December

I was pleased with how these two images came out.  The color entry was an after-thought.  I was reviewing my images from a 2009 trip to Colorado, and found myself attracted to this picture of autumn aspen trees. After making a vertical crop from the original horizontal image I decided it would make a nice print.  I liked the simple composition and of course the colors.  There is a bit of drama in the sky and just a patch of blue, all of which helped make a fairly even exposure. What I find interesting is that when, a few minutes ago, I went to my Web site to see my 50 favorites from this trip, this image wasn't even included!  This is why I think it is smart not to initially discard too many images. (I am going to add this image to the 50 favorites right after I finish this post!)



The black and white was taken on the same day as the color image.  This was along a gravel road to Crested Butte, Colorado.  I take all my images in color and do the conversion to black and white in photoshop.  It is difficult to know which images will look good in black and white.  I usually experiment with a dozen or so images before I find one that looks reasonable in black and white.  Here I only wish that the solid blue sky was behind the aspens on the right to provide greater contrast against the light bark of the aspens.  Nevetheless, the whispy clouds add to the image in my opinion.... I just wish the clouds were on the left instead.



12.03.2010

Club digital "salon" entries for December

These are my digital entries for my photo club's December digital salon. 

The elk was an early morning shot in Rocky Mountain National Park.  The lighting isn't particularly great, but I did get this bull to look up from his munching.  It was past sunrise when I took the picture, but because this meadow was in a valley surrounded by mountains, the sun had not yet risen high enough to flood the valley with light.



The seagull shot is along the coast of Maine.  It's not the most noble of birds, but I like the exposure here and the piercing yellow eye staring at me.  The salt covered chains bring a little of the environment into the image.



The butterfly was taken in a nearby butterfly house. I don't really like the deep shadows under the wings, but I do like the angle I had of the butterfly resting symmetrically on the single green leaf.