Having moved from a compact camera (samsung superzoom) to a bridge camera (fuji xs-1 superzoom) in the last few years it was only a matter of time before I would upgrade to a dslr. I recently took the plunge with a canon 7d camera and it appears to have been a very good choice. A big problem with my previous camera was an inability to crop images to any extent and still retain sufficient detail. This was due to low-ish pixel count and poor image quality due to camera lens and sensor compromises. With the extra pixel count of the 7d of 18 megapixels compared to 12 mp of the xs-1 allied to the bigger sensor and potentially sharper lenses available, i was hoping to take nature pictures and zoom in to the see the fine details such as the hairs on birds’ chests and insects’ legs.
I purchased the 7d body only and needed some lenses to use with it. This is quite a daunting task to a newbie like me but also quite exciting – it was so easy before with the fixed lenses cameras – the lens really needed little thinking about because it was what it was and I was stuck with it regardless. But now a whole new world had opened up to me – thousands of lenses at different prices, focal lengths, weights and various other mysterious specifications are available on the interwebs for my perusal. Lenses can be placed in subgroups depending on their usage, these include macro lenses for close ups, wide aperture lenses for portraits, wide angle lenses for landscapes and zoom lenses for nature. Many lenses of course have a combination of potential usages. The long-term plan was to get a variety of lenses to cover all possibilities and eventualities but I decided to focus initially on buying a zoom lens because getting good close-up nature images like those i’ve drooled over on flickr was a major reason for upgrading to the 7d.
So i wanted a zoom lens but which one? And which focal range? I was initially drawn towards a lens with as massive focal range like the Tamron 18 – 270. I thought this could give me the flexibility of fixed lens set-up on an dslr. Unfortunately, having read a few reviews there appears to be too much compromise with a lens with such a large focal range regarding image quality, i.e general image quality with these lenses isn’t very good. So i then looked at a very popular focal range – 70 to 300mm. These lenses generally have a better image quality and less compromise across the zoom. There is a massive buying choice from various manufacturers and at various specs. I tried a couple of lenses – the Sigma 70-300mm f/4-5.6 DG Macro and Tamron 70 – 300 f 4 – 5.6 DI LD Macro. I didn’t like these much mainly because of the fiddly macro switch system that they utilise at the end of their range. The switch works only when the lens is extended to 270 to 300mm and enables a macro mode – all well and good yes and useful for close-up insect shots. But if the focus is on a close object – which it more than likely will be when using this mode – the switch will not work and the lens remains fixed at 270 – 300 mm. You have to alter focus to a more distant point to allow the switch to be flicked and return the lens to normal mode. Weird – and annoying. Also these lenses, though fairly sharp, do not have image stabilisation which i decided was pretty important on a zoom lens, allowing for lower shutter speeds at long focal lengths.
After checking a review or two, i ended up buying a Tamron SP 70 – 300mm DI VC USM lens – it just edged out the Canon 70 -300 IS lens due to its slightly better specs. With the 7d’s cropped sensor, the range of an EF lens is magnified 1.6 times when used with it so my tamron 70 – 300 lens becomes a 100 – 480 lens when used with a 7d – yay! Great for nature shots. Its pretty good, much better than the standard non image stabilised lens and in my current limited outdoor tests i’ve managed to take some sharp bird photos. I did have a few problems taking landscape shots with the lens – images while apparently in focus where shown to be blurred when viewed in greater detail – though i will need to test more focus and aperture options and rule out user error before castigating the lens.
So i had the telephoto option covered with the tamron lens but also needed a wide angle lens to cover landscape and portrait shots. I went with the Canon 18-55mm IS, a very common lens and included in a large range of Canon camera kits out-of-the-box . But its a good lens and a cheap one, its an EF-S lens so is specifically built for crop sensor cameras and so does not give the 1.6 magnification of an EF lens. You don’t want any magnification in wide-angle lens, you want to get as much content as possible into the frame.
I also needed some sort of macro close up lens option for my camera kit. Instead of buying a dedicated lens i thought i would try extension tubes. These extend the distance between the lens and the camera body sensor, creating a macro effect. I purchased Polaroid extension tubes with metal contacts to take advantage of camera auto focus and auto exposure options. Without the metal contacts any electronic connection between lens and camera body is lost making the lens operate in a full manual mode with no aperture control and manual focus options only. In truth, using either standard extension tubes or extension tubes with metal contacts, the functionality of the lens becomes very limited – depth of field is very shallow and photographing moving objects is nigh impossible though interesting photos can be made if one works within the limitations of the set up.
Next stop for my collection is a dedicated macro lens, maybe a Canon MP-E 65mm, though being an EF lens i think its magnification capabilities are reduced when used with a APS-C crop sensor camera like the 7d. The magnification possibilities for this lens however are far superior to anything else on the market though i have heard due to these properties its usage is limited, kind of like carrying around a portable microscope! I would imagine in a field full of butterflies flitting about it would struggle to take anything meaningful so maybe a half-way house macro option would be the order of the day.