A few months ago I bought a Pentax Q system. While this camera is usually criticized for its very small sensor, I saw a tremendous opportunity for macro photography. I really enjoy the camera and use it for a wide variety of purposes with excellent results, but I have been hankering to try some snow crystal shots with it.
Why snow crystals? The sensor on the Q is a diminutive 6 x 4.5mm in size. A large snow crystal would be about that size, meaning that one could get a frame-filling snow crystal image (for a large crystal) at a simple 1:1 magnification, and smaller crystal could easily be photographed at 2:1. This makes for a much simpler setup than what is required for shooting snow crystals on an APS-C DSLR – where magnification needs to be 4:1 to 8:1. The Pentax Q is compatible with all my existing Pentax flash gear and focus peaking should simplify focusing. So I figure I’d give it a try.
So today, when it finally snowed, I tested the Q on my snow crystal macro setup. I usually use a reverse mounted 50mm macro lens (Sigma EX 50mm f2.8) on a bellows (135mm maximum) and extension tubes (180mm maximum). A flash is used to light the crystal from below. I decided to try the Q first with this setup, but just the lens and bellows. Due to how the bellows mount on the macro-focusing lens, they have to be extended to at least 48mm. So, here is a plastic ruler, the metric scale, taken with the Pentax Q and 50mm macro lens reverse mounted on a bellows extended to 48mm. As you can see, the frame covers less than 2 mm on the longer axis. That would be great for many snow crystal shots.
So here is one of my first shots. Not a pretty crystal, but the shot is clear enough:
One of the problems I saw right off is that the flash stays in P-TTL mode, even though P-TTL needs access to the lens’s electronic data to function properly. I could not figure out how to get the flash into manual mode, so I just worked with it the old-fashioned way, and put a diffuser over it to manage the power level.
So here is another shot – even at the minimum magnification, the crystal was too big to fit in the frame:
But… What’s that magenta rectangle in the middle of the shot? It can be minimized by desaturating the image, but I don’t like it. Here’s the desaturated image:
So… Plan B – skip reverse mounting and just use a macro lens mounted normally and shoot at 1:1 or 2:1. I tried the DA-F 100mm macro, but the working distances posed a problem with my tripod setup. So, back to the Sigma 50mm. The lens will go to 1:1 on its own and with a 25mm extension tube it will do 1.5:1. So I setup the Sigma 50 mm macro lens on a 25mm extension tube.
An early test - here again the crystal was larger than the 1.25:1 magnification that I had set up the lens for:
Here’s a very “fluffy” snow crystal lit by a flash from below and compact florescent lights from above:
By this time the snow had stopped… So that was it for today’s experiment. I’ll continue working with the Q for this kind of photography – need to work out what is going on with the flash and test some other lenses. I guess that the magenta triangle was some sort of lens flare from the reverse mounted lens, but there is still a bit of it in the shots taken with the lens forward mounted. I have never seen that in shots taken with other cameras (I’ve used this setup with the *ist-D, K-10D, K-7 and K-5.)
As for noise – at ISO 160 there is very little noise. The advantages of the system way out weight the disadvantages.
More experiments to come - assuming it snows some more! At the end of the day, the grass is till poking out of the snow. Less than an inch fell today, but more is coming.