Thursday, 9 June 2016

Mastering Your Kit Lens - Part 5

Normally you would not shoot macro images at the widest focal length but sometimes it works just fine.

Now that you know more about your mechanics and attributes of your kit lens time has come to look at the creative use of the wee beasty and we start with macro first.

Macro Considerations

Perhaps surprisingly, a good number of kit lenses are able to focus really closely, no they won't replace a Macro lens, but nonetheless you can get more than passable results.  In fact if you're prepared to crop a bit, which with modern day levels of resolution is hardly a challenge, we can get very good results.  

First a little tip, shooting a bit wider and cropping will probably help you get more consistent results with regard to focus and depth of field as the closer we go the harder it gets to obtain adequate DOF.  You wouldn’t believe the number of people I have in classes with macro lens focusing dramas!   Step back from the insect.....and crop!

Filters and Tubes

Beyond just using the kit lens we can always use a cheap macro filter (plus 2 diopter normally works well) to extend the macro reach or perhaps even a thin auto extension tube to go even closer.  The edges will never compete with your true macro lens for clarity but who really needs flower shots with tack sharp corners and the cost and weight savings are huge.  Just as an example you can probably pick up a set of three macro filters for less than $30.00 on eBay or a cheap set of Auto extension tubes for $40.00 to 60.00.

A decent Macro lens on the other hand will run to about $400.00 as a starting point!

One big advantage of Macro filters is they don't reduce the light reaching the sensor like extension tubes do so normally you can get away with a faster shutter speed. Anyway I have both tubes and filters and use them often.

This little fella was captured with a short auto extension tube and a Sony 18-55mm OSS E mount lens, no problems going close then and plenty of detail.

It might not be obvious, but this "Aquilegia" seed pod is very small, probably about a third of the size it appears on this page, again a short extension tube and Sony 18-55 OSS nails it with ease. 

Fixed Focal Length

Yes thats right you could use your kit zoom as a fixed focal length lens and in fact I mostly do exactly that.  Consider this, all zoom lenses actually have a focal length sweet spot, a point where the balance of all aberrations are best corrected, it is probably somewhere around the middle of the focal length range on your kit zoom but you will need to test to find out.

Generally for APSC lenses it is in the 24-28mm range and at those focal lenghts you are likely working with a maximum aperture of f4.3 or so, which in the scheme of things is quite practical provided the lens is nice and sharp at that setting.

For example my Sony 18-55 OSS e mounts' perfect spot is 27mm, at this setting CA is almost non-existent, there is very minimal distortion and the vignetting is not noticeable at all unless you are shooting blue skies.

In my case I have marked the lens up to easily find that 27mm setting and I use a big wide rubber band to hold it there, I just treat it as a fixed lens, even manually focusing most of the time.  I have no qualms about shooting wide open if needed as the lens is plenty sharp at that setting.

Ignore what you see in lens tests on-line, typically they only test the lenses at max wide and tele settings and maybe the 35mm setting so they almost never uncover the true jewell within in kitty unless by accident or good fortune 35mm happens to be the optimal setting.

This image is an example of using both pre-focus manual and fusing a fixed focal length on the zoom, in fact 60 -70% of all images I shoot with the Sony 18-55 OSS are fixed at 27mm.  In this case we were walking quickly through an alley in Hanoi and the fixed focus makes for reliable faster street shooting.

Pre Focus Manual

In ancient pre-digital times photographers regularly used a concept called “Zone Focusing” to quickly capture scenes with minimal fuss using direct vision cameras. It’s not complex and can be an amazing tool to improve your street photography or even family snaps.

Basically you pre-focus at a fixed distance and adjust the aperture to enable the Depth of Field to cover your needs. As an example you might fix your kit lens to 28mm and focus at 2.5 metres.  Referring to a set of Depth of Field scales on my iPhone   (I use DOF Master) I can see that with an APSC camera I will get from about 1.6m to 5.4 metres in acceptable focus using F5.6.  Which is just peachy for shoot from the hip street photography.

All I need to do is place my Kitty in Manual focus, focus on something at that distance  (2.5 metres in this case) place my camera in aperture priority  (Av mode on most cameras) set my aperture to f 5.6 and my ISO to auto and I am hot to trot.

It is super quick because there is no hunting for focus, or mis-focus on too distant or too close objects. Trust me I shoot stuff like this all the time, it works a treat and is often more reliable, not to mention far quicker and less obtrusive for candid work, most people just don't have time to react or don't imagine you could be shooting that quickly.

Many of the greats of Street Photography worked just like this, so you too can be your own Cartier Bresson.

Just Crop It

Should the 55mm end be insufficient for your needs you can always crop say the middle 70% out of the frame to get some extra reach with good clarity from edge to edge because you of course cut off those crook pesky corners.  Perhaps even better, a good number cameras will digitally zoom at moderate levels to render out a cropped but upsized JPEG straight out of the camera,  all Sony cameras for example do this, and they do it really well, they normally go out to 2 times magnification which makes your 55mm end equal to 110mm, but normally you can choose an 
intermediate option.

Now before you start throwing any hissy fits and howling at the moon in protest to “going the crop”, lets run some numbers. Say you have a 24 megapixel APSC DSLR and you cropped half the frame away, you'd still have 12 megapixels and most of the micro 4/3 cameras were that until very recently.  In fact if you cropped without resampling your 24mp frame to M4/3 dimensions you get around 14mp and a Full Frame equivalent of 110mm out of your std kit lens!   A 16 meg sensor will be less impressive coming back to about 9-10 megapixels but still that’s enough for a good sized print, like A3!

If you have a focal length that is a bit soft on the edges, sometimes you can actually get a sharper shot by shooting slightly wider on the focal length then cropping to match.  For example my 18-55 Sony is a bit rubbish in the corners at 35mm but terrific at 30mm, cropping the 30mm frame to match the 35mm angle of view actually gives a better looking image in terms of having even "cross frame clarity". 

And try this one on for size..... Often you just need a wider aperture to cope with low light levels.   Well now your kit lens is usually f3.5 at the wide end and gets down to 5.6 at the tele end.  Perhaps shooting at 18mm f3.5 and cropping the frame down by say 30% to 40% might just give you the aperture boost you need when the going gets really tough.  Oh and guess what, those in camera digital zoom functions work at shorter focal lengths too!

But there is more, lets say you have to take a group shot in a low light situation, and you need say 30mm to cover the group and f8 to get enough DOF.  Unfortunately for you, the shutter speed will now be too slow, ah but grasshopper try this.  Go wider than you need and you can then get the DOF you need without having to go too small on the aperture and bingo you can shoot at a faster shutter speed....just add the crop later.

All I had was the Sony18-55 OSS and of course the action was a bit far away, crop away I say, still looks fine doesn't it.

The Creative Crop Chop

Cropping to gain a magnification or f stop boost is fine and dandy but what about cropping for compositional improvement and how might that relate to kit lenses anyway.

If your camera is an APSC model the framing aspect ratio is 2 to 3 which has been around since Oskar shoved a roll of 35mm movie film in a little metal box with a nice lens attached and yelled Leica.  But photos can look great at all sorts of other formats, like 4:3,  4:5, 16:9 and that holy of holies of medium format, the square.

Now what do you think happens when we crop to any of these formats from 2 to 3?  Easy, we lose those pesky messy corners that our kit lenses don’t like to resolve.  It would have to be an utterly useless kit lens if when you cropped a square out of the full frame you didn’t end up with good to great corner to corner resolution.

The only fly in your ointment might be that if you shoot without actually looking through the viewfinder you could end up cropping not from the middle but into the corners to get the final image....but that will be your fault not the lenses.

I often advise my student to shoot a little wide these days to allow for creative post cropping that way you can get any final format you want, But don’t take that advise as an excuse for sloppy workmanship on your part!

 There is nothing sacred about a 2 to 3 ratio, crop to be creative and as a bonus that cropping might give you a better level of overall clarity as well.

What about You?

Whilst we're on the subject of reach, I could place a fair bet that a lot of the time you could get a bit more reach by just moving closer to the subject, you can use photography's greatest accessory to help, they’re called legs and amazingly most humanoids come pre-fitted with a pair.  (Moving closer will give your kit lens a really great boost in the shallow DOF department as well!)  Just ask yourself this, how often do you have to crop shots because you left too much around the edges of your pic when you could have, should have, moved closer with ease?

Be Prepared to Edit

Moving beyond the shooting, you really need to accept that most of the great images you see on the web are not just “out of the camera” jpegs.  They have been massaged and manipulated, tweaked, tinkered and stroked in a myriad of ways.  The editing is at least as important as the lens, so those great shots you saw created with a Zeiss 35mm on a Nikon D800, were they really OOC or were they edited?  
Fact is, you need to accept that editing and shooting go hand in hand, no company has yet come out with a DSLR lens that applies creative corrections and effects in camera without you moving a finger.

Another fact to chew on, most folk who can justify spending say 2Gs on a fancy lens have long ago worked out how to edit well.  A new lens is unlikely to be a magic bullet, but by golly gosh a new editing application and some real editing skills could prove to be close.

And here's a final insight for the post, any photographer prepared to do a little saving can buy a new or better lens so ultimately you won’t end up with anything 
advantageous in your possession by taking that path.  Good technical skills, 
creativity and solid editing skills are not something you can purchase off the shelf but are far more likely to yield great photographic results that stand you apart from the crowd.

Ok so next post we continue on our theme of creative use of the kit lens.

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