Wednesday, January 21, 2009

What is the deal with our 85mm f2.8 PC-Micro-Nikkor?

I've been asked for some samples of what our rental lenses are capable of- specifically, the 85mm f2.8 PC-Micro-Nikkor.


In addition to being an exceptionally sharp macro lens, the PC-Micro-Nikkor's big tricks are its tilt/shift abilities. What these allow is greater control over distortion and plane of focus, similar to what large-format cameras are capable of.

Shifting moves the lens off its axis, in any direction. This is mostly useful for architectural photography, but it can also be used to slide your viewpoint off-axis without moving the camera. So if you need to take a picture featuring some kind of reflective surface, and you want to make sure the camera doesn't appear in the image, shifting the lens may let you get away with it.

Tilting is more interesting for creative photography. When you take a picture, the area in focus is a slice of your subject parallel to the film or sensor plane. To illustrate:


If you tilt the lens, the area in focus tilts, too. So instead of having that in-focus area parallel to the sensor plane, you can lay it down against your subject so that more appears in focus:


Both of these ruler pictures were taken at the same aperture from the same spot.

Especially useful for macrophotography, where depth of focus can be a real problem, you can also get great effects from this technique in portraiture and landscapes. National Geographic published an excellent Hurricane Katrina photo essay taken with a Speed Graphic large-format camera, which features the kind of selective focus effects the 85mm f2.8 PC-Micro-Nikkor is capable of.

Part of our rental fleet, the 85mm f2.8 PC-Micro-Nikkor rents for $35/day.

Monday, January 19, 2009

Digital infrared: a how-to guide


Infrared photography is getting more and more popular, and with good reason: it's a lot of fun, and can give some fantastic effects. There are plenty of ways to shoot infrared, both film and digital. Our last update mentioned our stock of infrared film, which makes shooting IR pictures as easy as dropping a roll of film in your camera and attaching a filter.

But if you want to shoot digitally, you've got a few options. Digital sensors are actually very sensitive to infrared light, and the only reason you can't just go ahead shoot IR with most cameras is a simple filter placed in front of the sensor.
So to shoot infrared with a digital camera, the trick is to somehow remove that filter.

You can have a DSLR modified- an expensive proposition- or you can use a simple point-and-shoot camera and get a similar effect.
So today I'm going to go the digital route and show you how to modify an old point-and-shoot camera to capture IR images. It's cheap, and it' fun. We'll start with an old digital point-and-shoot camera, in this case a Toshiba PDR-M70. The PDR-M70 is a chunky old camera that has the good fortune of borrowing the lens and sensor assembly of the Canon G1, one of my favourite digital cameras. It has a nice high-speed f2.0-f3.0 zoom lens and a sensor which, at least at its base ISO, produces pretty solid pictures. And now we're going to cut it open.

You'll need the camera itself, a screwdriver, a piece of glass (I've used an old skylight filter), a glass cutter, a piece of exposed film leader, and some tape. You may also want to have some tweezers on hand.

1) Remove the battery to prevent damage to the camera and yourself.


2) Remove the screws that hold the camera together.


You may want to place the screws in a convenient film container so they don't get lost.


3) Gently take the camera's two halves apart.


Don't yank: you may have missed a screw or, depending on the camera you're dissecting, you may have to pry some plastic clips open before the two halves can be separated.

DO NOT TOUCH THE FLASH CAPACITOR OR ITS CONNECTORS!! Basically do not touch anything in the flash assembly: even though the battery is removed, it can still give you a rough shock.


4) The PDR-M70 is mercifully simple inside, and the sensor assembly is easily visible as soon as you split the casing (apologies for the blurry image.)


Unclip the data cable leading to the sensor assembly and move it aside.


5) Remove the screws holding the sensor to the lens assembly and store the screws in another film case.


6) Gently lift the sensor off the lens assembly.


7) The blue glass filter you see here is the IR filter. You'll need to remove it, and in this camera, it's a simple matter of popping it out with a screwdriver. Your camera may differ.


8) Here's the filter out of the camera.


Place the filter on your replacement glass, and trace its outline


9) Score the glass along your traced lines, and snap it.

Be careful with this step, because you're going to end up with a sharp-edged glass square and a bunch of smaller glass bits.
Here is the new filter next to the old one:


10) Drop the new filter into the recess previously occupied by the IR filter.


Here it is properly seated:



11) now you just need to reverse the disassembly and put the camera back together.

Click.

12) Now we make an IR-pass filter for the front of the lens, to minimize the amount of visible light reaching the sensor. You can buy a proper glass IR filter, or do it the cheap way with a piece of exposed colour negative film.


Just cut it to fit, and tape it to the front of the lens.


Looks ridiculous, but it works: the true spirit of DIY. You can also use a completely black frame of slide film, but don't use black and white film, because it's not gonna work.

13) That's it! The camera is done.


You now have a fully functional camera that shoots infrared pictures like this:


More here.

If you take on this project, be aware that the camera you choose to modify will probably be constructed differently than the PDR-M70 I used, so some of the steps I've listed above may differ. And your camera may require some sensor adjustment to get the focus correct (the softness in the IR pictures above is due mostly to a sensor that still needs a bit of prodding)

It's not dead simple, but basically, if you're inclined to tinkering, you should be able to figure it out. GIve it a try!

What's new this week - January 19th

We have a bunch of interesting film and a few cool cameras to talk about this week.

Cameras first: we have a nice Voigtlander Bessa R2A, one of the newer Voigtlander-branded Cosina rangefinder cameras.

These are modern rangefinder cameras with the standard Leica M-mount bayonet, TTL meters, and a big, clear viewfinder. They're compatible with nearly every Leica M lens out there, plus a multitude of 39mm screw-mount lenses available for earlier cameras. They're well-made, metal-bodied cameras- I've been using a similar R3M for a few years now, and it's been nothing but reliable.

The R2A has an electronically-controlled shutter, and operates in full manual or aperture-priority mode. If you've never used a rangefinder camera before, come in and have a look- the R2A is a good one, and sells for a fraction of what a similarly-specced Leica would. Our Voigtlander Bessa R2A is in excellent condition both cosmetically and functionally, and is priced at a very reasonable $369.

The second camera is a bit of an older one:

This is a very clean Zeiss-Ikon Ikonta 524/2, a classic 6x9cm medium-format folding camera. It has a clean 105mm f3.5 Novar Anastigmat lens, fully functional shutter, and a built-in uncoupled rangefinder. These old folding cameras are great, shooting huge pictures on 120 rollfilm and collapsing down to a size that's easily packable into nearly any camera bag (or pocket, I suppose, if your coat is big enough.) This Ikonta is in-store now and priced at $129.

On the film front, we've brought in a selection of some harder-to-find emulsions, including three different varieties of infrared film.

Ilford SFX200 is an ISO200 black-and-white film sensitive to wavelengths up to roughly 790nm. We have SFX200 available in both 35mm and 120 formats.

Rollei IR400 is a slightly faster film with approximately the same infrared sensitivity as the Ilford SFX200. We have only 35mm cartridges of the Rollei IR400 at the moment, but we'll be getting more 120 soon.

Efke IR820 is not an ISO820 film: the name refers to its infrared sensitivity, which at 820nm makes this more of a "true" infrared film than either the Ilford or the Rollei. Efke IR820 is available in 35mm and 120 formats.

Rollei Digibase is a special C41-process black and white emulsion specifically designed for scanning. Its polyester base has no colour mask, and lies flatter than standard film bases to ensure edge-to-edge sharpness. Available in 35mm and 120 formats.

And finally, for the classic camera fans, a special treat:

127 film! This is a smaller rollfilm format used by Rolleiflex 44 and Yashica 44 cameras, as well as many other older cameras. This is not a common film- the 127 format has been out of mass production for more than a decade now- but Efke still makes it, and we've got some. It's a nice-quality ISO100 black and white film, with a silver-rich emulsion that gives great classic-looking photos.

That's it for this week. Be sure to check our used inventory at www.camera-traders.com for all the rest of our stock- and contact us if you have any questions about these or other cameras.