31 August 2007

New DA* Zooms In Singapore

Two days ago I trooped down to a IT and electronics fair with two friends to catch a glimpse of Pentax's new DA* offerings: the DA* 16-50mm f2.8 and the DA* 50-135mm f2.8. These long anticipated lenses are the first new offerings from Pentax as outlined in their lens road map.

Pentax's reputation for zoom lenses has in the past been a mixed bag. Some very good ones interspersed among generally average offerings. Well a quick tryout at the Pentax stand was enough to convince me that these new zooms are pretty special. Well they ought to be, given the DA* label, which Pentax gives to its lenses that offer the highest level of optical quality.

These two lenses are unique because they employ Pentax's new supersonic motor which makes for whisper quiet and fast autofocusing (similar to Canon's Ultrasonic lenses); plus dust and weather sealing is incorporated in the design. The SDM is really an impressive feature in my mind and definitely a step up over the conventional screw drive AF.

The 2 lenses look big, thanks in part to their big lens hoods but considering they are large aperture zooms, that's to be expected. The real surprise is that these lenses don't weigh a lot and are pretty balanced, the 50-135mm especially so.

Having already got the DA 16-45mm f4, I personally feel the DA*16-50 doesn't't offer very much more other than the 1 stop difference in aperture, additional 5 mm focal length on the long side, SDM and weather sealing. Like the DA 16-45mm, the DA* 16-50 mm lens barrel extends quite a bit when zoomed.

Being more than double in price, I'll be keeping the DA 16-45 f4 for quite a while longer. Much as the DA* 16-50mm is a better lens, I feel that it would have been a more attractive proposition had the focal range gone 10 mm more on the long end. And oh, by the way, that's the new K100D Super as well.

To me the DA* 50-135mm is by far the more impressive of the two lenses. This lens restores the popular 70-210 mm focal length range in 35mm film format because of the crop factor. Easy to handle, the lens barrel doesn't extend in length when zoomed and as a tele zoom, the faster focusing provided by the SDM is notably evident. Image quality is very good, as is the contrast. The bokeh is nice too. Again weather sealing is present. I predict this lens is going to be even more popular and versatile than the DA* 16-50mm Definitely a lens that's on my wish list.

Sadly the local list price for the two lenses here in Singapore is a little steep and coupled with a 7% goods and services tax, it's not so attractive for me to buy any of them locally.

28 August 2007

Dabbling in IR Photography

Infrared photographs intrigue me. Ordinary scenes take on a new look when given the IR treatment and suddenly the mundane become extraordinary.

Recently I took the plunge to try out IR photography using my Pentax K100D by buying a Hoya R72 infrared filter. That R72 refers to the cutoff wavelength where visible light gets filtered out, in this case below 720nm. The Hoya R72 is about the cheapest branded IR filter available, though there are online sellers from China that sell their unbranded IR filters quite a bit cheaper.

I've taken pictures for quite a while now and thought that taking IR pictures would be pretty simple. Was I dead wrong! My initial pictures turned out all red. Not knowing what to do next, I was prepared to abandon all thoughts of dabbling in IR. Fortunately help came in the guise of a friend on the photographic forum Clubsnap. Not only did he gave a detailed walk through of the IR work flow but a hands on shooting session helped clear up any issues.

My initial pictures were taken with the Pentax DA 16-45mm during dreary overcast weather, not the sort of weather conducive for nice IR images. The DA 16-45mm exhibited some hotspots and a washed out centre. Not the most suitable lens for IR.

The images here are from my second attempt using the DA 18-55mm kit lens at the Singapore Botanic Gardens. Surprise, surprise, this lens proves to be excellent for IR photography. One thing to note is that since plants and leaves reflect a lot of infra-red, they will appear brighter while blue skies have little or no infra-red and thus will appear darker in IR photography. All images shot handheld with the Pentax kit lens at ISO 1600 with no cropping using a 52mm Hoya R72 IR filter.

Essentially, taking IR photographs is a 2 step process: taking the image and post processing.

To shoot IR you need your DSLR, an IR filter for your lens and a tripod. The Pentax K100D is in this respect better at taking IR than the K10D. The K100D sensor is more sensitive to IR and allows shorter exposures than the K10D. Setting the custom white balance is also easier.

This instruction applies to the K100D but if you're using the K10D or some other camera, you'll need to experiment accordingly. Thanks to Wee Kiat for the following pointers.

WB Setting
With the IR filter attached to the lens filter mount, take a custom white balance reading of something green (like green grass or leaves) in strong light. Make sure the entire frame is filled by the green subject. Getting the custom balance right makes all the difference in the colours you're gonna get later. There are other methods to set WB that I have yet to try, like using a custom WB filter but this one works.

Remove the filter from the lens, compose the scene in the viewfinder, affix the filter again and look at the camera's meter reading. You'll need to do this because once the filter is in place, you'll see next to nothing in the viewfinder. It would be a good idea to use a tripod because exposures can exceed 1 second, depending on the subject brightness, weather condition/time of day and aperture setting.

Setting the camera to full manual mode and using RAW mode is best. Ensure that the exposure combination you set indicates between +2.5 to +3.0 times over the what the camera's meter reading indicate. Using identical K100Ds, my friend and I found out that IR sensitivity can vary slightly from camera to camera. Take a shot. To check if the exposure is spot on, look at the histogram curve on the LCD. It should be kind of even and your image should appear to have a sepia like tone. Bracket if necessary.

Post Processing
The second step relates to post processing. If you're using Pentax's Photo Laboratory, click the grey point setting on something that you know is green in the scene (a leaf, tree, etc.). Save the file. The image then needs a channel swap to give it the characteristic IR look. In Adobe Photoshop, go to Channel Mixer and change the following settings:

1) Red channel : Red 0 Green 0 Blue 100
2) Blue channel: Red 100 Green 0 Blue 0
3) Green channel: Red 50 Blue 50 Green 0 (you can experiment on the red and blue amounts but it should add up to 100)

From here onwards, you can experiment freely by adjusting saturation in Hue/Saturation, curves, add a tone, adjust shadow/highlight etc. limited only by the effect you want and your free expression. For example, the shot above has been post processed a little differently.

IR definitely is fun and the K100D with the kit lens make an excellent combination. Go try it!

18 August 2007

Cheap Superzoom

Have been busy lately but managed to grab a few shots using a Tokina SZ-X 28-200mm f3.5~5.3 zoom. A manual focus lens in PK-A mount, this was one of the early versions of the wide focal range zoom we now call superzoom. Optically it isn't too bad but obviously it can't match a prime lens.

Usually I'd steer clear of superzooms because convenience usually doesn't come cheap and there are compromises using these lenses (physical size and weight, optical quality and contrast, aperture size, minimum focusing distance, filter diameter). However a local store were clearing them for S$45 brand new (about US$28) and the bargain hunter in me took over!

The Tokina is very solidly built and has a very short focusing throw. Being a superzoom filter size is a big 72mm. Took these images in fading light and thanks to Pentax's in-body Shake Reduction, the images are acceptably sharp, even at the 200mm end. Will post more images with this lens later.

10 August 2007

Macro Lenses Part 2

Another very affordable macro lens that I recently got was the older Sigma 90mm f2.8 Macro. A very compact lens that goes to 1:2 and life size with an add-on close-up lens. A manual focus lens that comes with a big lens hood. Very nice too as it's felt lined. Paid about 70 Euros for it in mint condition. Much nicer build quality compared to the Vivitar/Cosina. While I like my Voightlander Macro Apo-Lanthar a lot, this lens is light and compact, which means I get to use it a lot.

Fruity breakfast

Here's some very recent shots taken with the Sigma. As you can tell I was playing around the breakfast table. Beautiful colour and nice bokeh. K100D with no cropping.

Pear Slices

Apple Strudel

Bird Park Images: Who Needs AF?

Some pictures taken at the Jurong Bird Park. here in Singapore. All taken with the K100D. Manual focus, handheld.

Scarlet Ibis Voigtlander Macro Apo Lanthar 125mm

Flamingo gathering Tokina 60-300mm

Crowned Pigeon Tokina 60-300mm

Shoebill Voigtlander Macro Apo Lanthar 125mm

Stork Voigtlander Macro Apo Lanthar 125mm

Red Macaw Tokina 60-300mm

Considering I paid less than US$50 for the Tokina SZ-X 60-300mm telezoom, I can safely say I got a bargain for this new but older manual focus lens. No AF but I can live with that.

For those who shoot manual focus or want a better view of the viewfinder, my suggestion is to replace the existing factory eyepiece with the Pentax O-M53 eyepiece magnifier. Increases magnification 1.2X and works on the K10D and K100D. A little hard to find but very useful because once you've use it, you don't want to go back to the original eyepiece that comes with the camera.

For Pentax users, there is literally a treasure trove of older manual focus lenses that can and will work with the Pentax. This backward compatibility is really a great advantage, given that Pentax is only slowly rolling out its range of new lenses.

Whereas other camera manufactures have compatibility/functionality issues for older lenses on newer cameras, some like Canon have completely abandoned the use of their older lenses (Canon's FD mount). That limits their current bodies to newer and probably more expensive new lenses. Pentax has continued to extend a new lease of life for the older K mount and M42 lenses. A good thing in my book because it saves me money.

07 August 2007

Talking About Macro Lenses: Part 1

I've come to love macro lenses in the many years I've toyed with cameras. Not that I'm a serious bug hunter or anything of that sort, far from it. For me it's the versatility and flexibility of shooting a distant subject one moment and close-ups the next that gives the macro lens an edge over many other lenses. Unlike a zoom, the predictability of angle of view means that I can quickly determine what's going to be covered. Plus the adage that there are no bad macro lenses is true which translates to nice sharpness and colour.

These shots were taken by a very cheap manual focus Vivitar 100 f3.5 Macro. Made by Cosina, this lens comes in many different names as there are camera mounts both in manual and autofocus. The lens barrel is very plasticky and many photographers I know cast the "can't take it seriously" look whenever they look at this compact dinky lens. However in terms of image quality, this lens gives results far better that expected. It focuses to 1:2 and goes to 1:1 with a diopter filter attachment. Bottom line, it's cheap and good despite the dodgy build quality.

Here's how it looks like (manual focus version).

04 August 2007

Doggie at the doorway

Well before I plunged into the world of Pentax, I had this Nikon Coolpix 5700 prosumer. One of those purchases that was influenced by slick marketing brochures with impressive technical specifications. Not a bad camera image quality wise but it is really a slow camera to operate.

Slow to power up, slow to focus, especially in dim light and that electronic viewfinder is just a case of being too clever. That said, I might use it to take IR pictures as I am told it is a capable camera for infra-red photography. But why am I talking about this particular Nikon? Well the reason it gets mentioned is because I took a nice shot of my pet chihuahua Pepe some while back and in the process of searching for another picture, chanced upon this shot. A little soft but passable. BTW, if ever you need a good watchdog, this breed is it. Not too sociable compared to other breeds and requires quite a bit of attention.