Saturday 11 June 2016

Tests and More Tests







NOTE:  This is a rejigged version of a much older post from my  01imaging.com  website, I have made some small changes to bring things up to date but the content is still perfectly valid.


As I have mentioned elsewhere on this blog, I feel too many folk are inclined to throw money at their photographic problems in order to chase that elusive concept of higher quality.  Those who retail photographic gear are more than keen to promote the idea of better equipment being the best pathway to improved photos, which is fair enough, higher quality equipment will certainly help (note I said higher quality, not more expensive) and of course the camera sellers have to make a living.

In the overall scheme of things, your best pathway to imaging nirvana in at least a technical sense is not more expensive gear but a better understanding of what you can do with what you already have combined with some good technique.  There are photographers who shoot brilliant stuff with just one camera, one lens, and the same old gear they have had for years. These are not generally photographers who are stingy or have no interest in gear, more likely they have come to realise that the best photography is often created when the gear doesn’t get in the way and that usually comes from having a really thorough understanding of how their equipment responds under all photographic situations, which was of course the topic of the last blog post. Sure, there might be limitations with their equipment  and your equipment but really good photographers simply work around them.

And quite frankly a lot of Pros eventually come to the conclusion that they waste far too much money on stuff that really doesn’t make them any more money, and then they start the rationalisation process.  I will give you a free inside tip here, most of the Pros I have known have all gone through periods of massive GAS, (gear acquisition syndrome) and most have wasted many thousands of dollars on the wrong gear so there is nothing unique in amateurs doing exactly the same thing, we all love shiny new things, you will get over it!

The lesson here is that modern photographers have more gear than you can poke a monopod at but often have very little knowledge of how it all works and simply leave things on automatic, never realising the potential just waiting to be unlocked. All this is understandable as the marketing of lots of gear tends to take the old Kodak line of “you press the button and we do the rest”, so consumers get a distorted concept of what their gear should do and then when it fails to measure up they go in search of something better or perhaps they enrol in one of my classes.

So how might you improve your photography results in a technical sense?  Test, test and more tests.  

See it works like this, if you want to know how to get the best out of your gear, you are going to need to know what happens under different circumstances.  Think about these questions and see if you really know the answer for sure.

Do you know how far from correct colour your digital camera sways say when on the daylight white balance setting?

Do you know if your DSLR really is focused on a specific point when it looks like it is through the viewfinder, many combinations slightly back focus or forward focus a bit?

Do you know which aperture on your main lens really is the sharpest overall?

If you shoot RAW just how far out is the histogram, most tell you the shot is overexposed a bit, when the RAW file isn’t, mainly because the histogram is a readout of the jpeg file, but just how much leeway is there?

And on it goes.

Really you can take just about any camera and after some solid testing work out how to use it better and thus reap better results, sometimes the difference will be very dramatic.

Of course testing doesn’t just apply to the camera. Scanners, printers, monitors can all be better used if you run a few tests so you can eliminate the variables, lets just look at one example that I have been working on recently.

A few years back I shot quite a lot of film and as a result needed to get my sleeves rolled up and scanning, which is no drama, I quite enjoy it, but I started to wonder if I was getting the best results possible from my now ancient Epson 4870 flatbed.

The Epson 4870 is not a dedicated film scanner so it is a bit nobbled to start with, but the idea of spending a couple of grand for a second hand film scanner (I am lusting after a Nikon LS5000) doesn’t really thrill me, though I am quite sure the performance gain would be peachy.

So back to the Epson, I had shot some Ilford XP2 super (a chromogenic monochrome film) and the scans and files looked pretty good, all things considered, but it seemed logical that film buckling must have some effect on the overall sharpness.  Pondering this question I thought, well why not cut the negs out that I wanted to scan and mount them into slide mounts for scanning, so I decided to test to see if it helped.  Yes is did, the images were clearly sharper across the whole frame.

Ok that’s good, but then the next question was, will there be a difference in the clarity depending on where the slide/neg is put on the scanning bed, well a few test frames later it was obvious that the close to central spot was best, which I had kind of expected.

Good, but does the scanner really focus as accurately as possible at the standard depth of the film from the platen when in a standard slide mount, once again a few tests later I had the answer, no it doesn’t!  Raising the slide by the thickness of a 240gsm sheet of paper gave the best result (we are talking small variations here).

So now I was able to see the combined effect of three small changes compared to the standard scanning set-up. Is it worth the trouble, too right it is, the difference is about what you might expect if you bought a newer, better scanner.

Is this the end of it, NO!  Checking the 3 colour channels in Photoshop (I scan the monochrome negs as colour) reveals that with this scanner when scanning XP2 the red channel has quite a bit more clarity, I would have expected the green channel to be best, but there you go, the testing proved me wrong.  So if I dump the green and blue channels and retain the red channel the image is better!

But wait there’s more! All scanners produce some image noise of their own, there is an automatic feature available in some scanning software which scans the frame several times then blends the multiple scans together before saving the final file.  In essence, because the noise is random in each frame, multiple scans will cancelled it out across the multiple frames, in addition it can also increase shadow rendering with slides.  There is no multiple scan feature in my Epson’s’ scanning software however I wondered if I made 4 separate scans then blended in Photoshop what might the result be. (I can now do this with later software updates) 

The good news is that it did indeed lower noise, added a small degree of additional clarity and it made for an overall better looking result.

So there you go, a whole series of little tests that in this case gave great results and ultimately a far better image, quality-wise, yet I didn’t spend a cent, just burnt some time.

The thing with photographic image quality is that no single item is responsible for the final result; rather great final image quality is the product of care and attention applied in a myriad of little ways throughout the imaging chain.  

All those little changes add up to a better end product and simply buying more gear will likely not be as beneficial as better application of what you already have. If you don’t test you will never know, and don’t think taking someone else’s word from an internet forum will shortcut the process, most of those giving comments and advice probably know no more than you do and many of their results are open to personal interpretation and system variations. Friends there is no choice, you have to find out for yourself.

So run some tests on the various bits of gear in your imaging chain and see what is possible....then of course if it comes up short feel free to part with the extra dollars, if you’re sure it will help. I suspect however your expenditure on new gear may in fact be somewhat less than it is at present.

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