Monday, 31 October 2011

Halloween

Monter Mash was a favourite of mine as a kid ... I even have the LP

Now thanks to Ben I have a doll doing covers too



the details on the doll are sorta cute, with the neck bolts


and the chorus pumkin


ya gotta love that pumpkin

thanks Ben

Saturday, 29 October 2011

Scanning as neg or scanning as pos

This topic comes up again and again, with people not seeming to actually do anything to verify their work. So I'll put up this post to clarify differences I see when I scan negative on my Epson scanner with the supplied Epson software

I usually scan negative as positive and invert, the reasons are mainly that I get better control and I prefer the results I get. If you don't like to scan this way then by all means don't. If you think that you may gain something from this work flow then what follows are my reasons and some evidence.

Keep in mind that no matter what, the goal here is to produce a result that gets you a satisfactory image from your negative. If you can reliably and consistently get satisfactory results using a method then aside from learning about alternatives for "just in case" then by all means stick to the method you prefer.

Having said that I will say that over the years of scanning I have many times come back to stuff and thought "gosh, I know I can do better with that now". So if you happen to be reading this thinking about scanning your life's work of negatives once and for all just keep in mind that scaning can be a journey of learning.

You may also find the following useful links:



Firstly Methods


I thought I'd start with a slightly over exposed negative. This will exacerbate the problems associated with trying to get shadow details, especially if one follows expose for the shadows and let the highlights fall where they may. I began by setting my Epson 4870 scanner in professional mode and scanned in a variety of ways. I notice (as previously observed in this post that (among other things) scan times varied.

Below is a table of my operations and results, note the changes in scan times in different operations:

Neg as Pos
scan 1 33:95 default adjustments
scan 2 34:00 auto exposure
scan 3 45.61 manual setting, blue hard right

Neg as Neg
scan 4 42:33 auto exposure
scan 5 42:49 manual adjustment of levels

You will find the images named accordingly.

I am not certain as to why there is a scan time difference but I find that the only explanation that makes sense is that the scanner is making alterations in exposure time. Its interesting to note that the scanning of Negative as Negative results in nearly as long an extension of exposure. Previously I have noted that some extension of capture can be found into the darker areas using epson scanners by altering the scan time in the above manner. How much is not a lot, but if you want it, you may just be able to pull a little more out (again also previously discussed).

So now, lets look at some images. Please note these are hosted on Flickr, so feel free to open them in another tab for closer examination if you require.

Firstly lets work with linear data

So scanning neg as pos the first three operations give the following results. Please also note that its important to assign the correct colour profile to your scan after capture. I have mine set to EPSON ColorMatch RGB ...

Again, I prefer to set things myself because I think "never send a machine to to a humans job" (unless you want an insensitive result).


scan-fig3

We can see perhaps there is different contrast ... so now, inverting the image


scan-fig4

Definitely there is different contrast. Clearly we get different shadow details here ... as well as different contrast. And naturally there is different colours as I have not perfectly tweaked each image to match the other yet.

Looking into details in a area of high contrast we see this:

scan-fig5

Dense and inky shadows on the two images done "default" and "Auto" but much better shadow details on the image 3. I happen to think the middle image is about right on colour.


By setting the capture area of the scan (the black and white points) we can capture the density range that negative has. As I have mentioned before negative does not have an even or a linear response. There are some good reasons for this and its not a mistake or a design failing.

The R G and B layers are at different density for a given exposure AND have a different range of density.

So its important to tweak that as soon as you can.

Because each film will have different response characteristics I think its essential to apply curves YOURSELF. One can use the "neg pos" software that has already pre-programmed in various films, but the last time I examined that, it resulted in a much noiser blue channel. I believe that this is not related to the software, but to the way that the scanner driver is handled and the changes that alteration can make.

Of course the linear scan is a little lacking in contrast, and so tweaking it (I only bothered with scan 3 on the right) we get a more 'natural' looking image of the scene.

scan-fig6

So we get a little better shadow details in the image ... but then that may not be noticeable or needed. It is however there if you did need it rather than not being there.

In my opinion this method allowed for better and more accurate setting of black point and seems to have resulted in a better output. I believe that this is related to there being more information in the "heel" of the image (dark is dense on negative) particularly in the green and definately in the blue.

Lets now look at the results of scanning negative on the negative settings


Firstly lets look at what we see in the scanner driver .. we see that the default settings leave red in the middle, and a curve being applied already


scan-fig1

but apply a CURVE to the data which does not occur when you scan negative using the positive setting.

The more you adjust the black and white points, the steeper that curve is ... and please note that its not a linear curve. The blue now appears more moved over to the right than it did when you were viewing it as a positive.

scan-fig2

and you'll also see that the curve bellies out more ... I guess that it could be "up to you" to decide if more or less processing in the scanner driver is better or not.

Without a doubt in my mind if you are not editing this in 16 bits, do as much in the scanner as you can.

Now lets over lay these two scans on top of the other 3

scan-fig7

Now, looking at this I think its clear that Scan 4 (which was auto exposure) actually looks less contrasty than the Scan 5 (which I set manually) but BOTH are more contrasty and darker than the linear scan.

Perhaps you can tweak this in photoshop, but pulling the curve back out will result in loss of information due to the integer nature of the data. You can not do log maths on integters in an orthogonal way and not expect data loss.

This supports my experience that scanning negative as negative applies way to much correction to the image and throws away data which you don't want to happen. Its even worse when you look into the shadows as below.

scan-fig8

Both Scan 4 and Scan 5 are much much murkier than Scan 3 (which follows my recommended negative scanning method).

Finally
I am only reporting what I find, if you want "the truth" go to church and the preacher will tell you what to believe.

If you ask questions about my findings I'm happy to reply. I do get a little bored with the simple re-iteration of the initial question, implying I'm wrong while not providing any of your own evidence and general not reading of the posts I link to. Questions about those posts are happily answered as I am not a professional writer I may make my posts with assumptions not properly clarified.

Friday, 28 October 2011

The Nikon 1 series

I've been eyeing this off for some time and wondering if its a crock of under done technology in an over done marketing dressing.

The fact that the Panasonic G1 took ages to get any sort of market traction yet seems to be a screamingly better package for less money seems to cement that the Nikon is just showing what can be done with an extensive marketing network and public ignorance of what anything means.

I am tempted to believe that there may be something in the entire system, particularly with the fast AF and the availablity of interchangable lenses.



The sensor is smaller than the 4/3 (as seen above) but is still much larger than the old "pro-sumer" market of digital cameras (such as the Canon G series). Once upon a time people wanted to move towards DSLR cameras because they had a better pixel density. The less pixels per square area means that each pixel can get more light. Its sort of like carving a pizza into more slices and pretending there is more food.

The graph below shows the pixel density of successive cameras, I've started it with my 2002 model Coolpix 5000 (which is a 2/3" sensor and was a great camera in its day) and moved along towards the new Nikon 1



The Nikon has much lower pixel density than my G1 panasonic, which likely means it'll have more noise. Its interesting how we've come full circle back to where we were in 2002. I wrote this article some years back, but it seems none the less relevant now.

Perhaps Nikon is re-entering the pro-sumer market with a more capable camera (sneaking up the sensor size I mean)? Certainly when compared to the winky dink little sensors put into cameras like the Canon Powershot range (even the G12) this new 1 series will be a better performer.

But something smells badly with the marketing push IMHO.

Tuesday, 25 October 2011

SlowMo HighSpeed Jets

The Gold Coast 600 was on this weekend gone and there was an FA18 flyover to mark the beginning



I'd rate this as the most boring flyover I've ever witnessed. What it lacked in quality it did make up for in quantity and duration. I guess this is what the bogans want right?

I wonder how much it cost to have that many Jets in the air for that long (and getting them all rallied together)

Monday, 24 October 2011

tracks in the sand

One of my the bloggers I follow (Jao) recently did a post on animal tracks in the sand ... this made me think of the times I'd seen similar stuff here.


These are from a sand blow ... not far from this point




Its really good to be up in the early morning before people are up ... everything is quiet and you can see the tracks of those gone earlier in the day.

There's lizards up and around in the early morning


and this crab too

Friday, 21 October 2011

Portrait lenses: 5D vs GH1

One of my favourite words is fungible. I'd never heard of it till I worked in the Finance industry (and who'd have thought but its a finance namespace word). Its defined over at Wikitionary as:

Adjective

fungible (comparative more fungible, superlative most fungible)
  1. (finance and commerce) Able to be substituted for something of equal value or utility; interchangeable, exchangeable.

With that definition in mind, the purpose of todays post is to explore the fungiblity of 50mm on 4/3 vs 100mm on full frame.

background


When digital SLR cameras came out I was unimpressed by the APS size sensor. I felt that it twisted lenses into something I was not used to. My fine 24mm wide angle became a middle or nothing semi-normal and my favourite normal (EF50) became some sort of half assed tele (something like 80mm which is too short IMHO). I ended up needing to buy alternative zoom lenses to cover the angles I liked and the DoF was never what I wanted.

Then I tried 4/3 and found that the x2 factor on the lenses was much more acceptable to me than the x1.6 of APS. I did find that the optical SLR viewfinder was pathetically small and so it wasn't till micro4/3 came out with the electronic viewfinders that I was fully comfortable with focus (and yes, I had a number of focus problems with APS cameras which included backfocus and front focus issues as well as inability to clearly manual focus on the small focusing screens).

Since I started using micro4/3 cameras one of the questions I have sought answers to is the ability to substitute half the focal length at 2 stops brighter and get the same thing. Back in March 2010 I made a comparison of this however I used 35mm negative, which didn't fully satisfy my interests because I still wonder about the utility of a 5D in what I photograph.

As I recently borrowed a 5D (for testing the Olympus 21mm f3.5 wide) I thought I'd do another test to satisfy my curiosity (and of course provide information for others pondering the same thing).

Too many reviews compare things with no context other than the optical one. I think that's invalid because I don't know anyone who just buys based on what the magazines say. Most people need reach into their pocket and pull out some money. So in someways there needs to be an examination of cost benefit. So lets examine some costs.

Both the GH1 and the 5D are only available now as used cameras (which to me is a good thing as they are cheaper this way, let someone else take a big depreciation hit if you can). A good used 5D body still fetches about $1000 while a good G1 about $250 and a GH1 (if you were after video as there is no other significant difference between the G1 and GH1) about $400.

The lenses uses in this test were the Canon FD 50 f1.4 and the Olympus OM100mm f2.8 - one can expect to pay about $100 for the FD50 1.4 and about $200 for the OM100mm f1.8 So one can take advantage of cheaper lenses. Because shorter lenses cost less than longer ones of equal quality and also 50mm was once a really popular focal length.

Then there is size the 5D is about twice the dimensions of the G1

So not only do you pay twice as much for the 5D as you do the G1, you have to carry around twice as much of a monster.

People often discount this fact when making considerations and instead ruminate about "what makes the ultimate image".

This "ultimate image" nonsence forgets an important fact in photogaphy: if you don't have your camera with you then you can't take pictures with it.

Hmmm?

This is of course why I bought a G1 and sold most of my EOS gear back in 2009 (after much rumination and after buying the G1 and having if for some months just to be sure).

Clearly then this test is not without me having some pre-conceptions from the outset. I think its important to say that some of my preconceptions were upheld here, while others were challenged and I think its fair to say I learned something in here which I didn't expect to learn (but wondered about in another context)

examination


In this test wanted to examine how well the micro4/3 camera would hold up against a full frame camera in respect to portrait focal lengths. I chose 100mm for the focal length because I've always like it more than 135mm. Canon and Nikon and Olympus alike have all made good sharp f2.8 100mm lenses for some decades. I happen to own a Olympus OM100mm f2.8 which I think is one of the sharpest lenses ever made (the TS-E90mm would get my vote as the best) and the 135mm range is a bit patchy if you ask me. Likewise there are plenty of good 50mm lenses out there (I own a few of them) which of course makes the basis for this comparison.

So to compare a 50mm lens on micro4/3 to a 100mm on a full frame one needs to consider that to get the same DoF look and feel, you need to keep the aperture 2 stops brighter on the 4/3 camera. So in theory 50mm @ f1.4 <=> 100mm @ f2.8. But of course its not without problems because (among other things) the aspect ratio is different the 4/3 format is far more square looking than the 3/2 format of full frame.

Notice that when covering the same width that the 4/3 gives that bit more along the top and bottom.

Next I'll state that all images were taken
  • in RAW
  • on a tripod that didn't move
  • converted using ACR 5.6 with exactly the same parameters
  • exposure set by my Gossen light meter and manual setting applied to the cameras
This was done so as to get the images as close as possible in terms of processing (camera JPG's would be more difficult for the nature of this comparison)

Something which came out right away was that: if you are taking shots in full sunlight that using f1.4 is a challenge.

The shutter speed required is often exceeding what your cameras shutter will allow. For instance on a sunny 16 kind of day (like this was) I was using 4000th of a second to get f1.4 and even then was needing to have shadows as part of the picture or have a washout. Check the nuclear glow of the shirt back for instance. At 4000th of a second fill flash is out of the question too.

So it seems that fast lenses and daylight are not good friends.

So anyway now lets take a look at the images.

First the image from the Olympus 100mm at 2.8


and then the 4/3 camera with the 50mm at 1.4
The first thing I notice is that the colour and contrast is different (there is also bokeh but that's for another post). The FD 50 when opened up to 1.4 is really soft and dull looking which influences the colour. This is clear in the 100% view below, especially where the stark contrast border between the white velcro of the cap strap borders the darkness of the hair in shadow.


Don't get confused and think this 'flare' only exists where there is bright light, it exists all over the image area and is what serves to make the lens "low contrast".

If we now look at the OM100mm at f2.8 we see definitely better contrast.



Its interesting to note however that the outright resolution of detail between the two lenses is quite similar.

This is consistent with what pulled me away from my 10D and 20D cameras in favor of the Panasonic G1 ... it just has heaps of detail.

On that subject its a good time to observe that the 5D turns its 36x24mm capture area into 4368 x 2912 pixels while the G1 divides its (much smaller area) 18x13mm into 4000 x 3000. This means that while the outright capture of detail is quite similar the micro4/3 is actually a little more demanding of lens quality. Since the FD50 f1.4 (or in fact almost any super bright lens) has always been regarded as a little soft fully open, it translates to a bit more than that here.

So when you stop the FD50 down to f2.8 it clears up immensely

to be more or less equal to the contrast of the Olympus 100mm lens.

but of course loosing that nice shallow DoF. I encourage you to open up each of the above images in a separate tab to allow you to click between tabs and see the differences jump out.

Perhaps the new Olympus 45 f1.8 lens would solve these problems and yield a lens which would
  • have the contrast I find in the Olympus 100 f2.8 on full frame,
  • have at least similar (if not better) sharpness
  • be more compact and light weight than the FD f1.4
The lens will set you back about $400 as it seems to be panning out, which is quite attractive. The initial discussion of the new Oly 45f1.8 indicated prices would be much higher, but if it does come in at $400 that will put it right on par with the typical 100mm f2 lens.




So you would then get the compact benefits of micro4/3 without needing to pay through the nose for smaller.

Back when micro4/3 came out there was of course no such lenses available, but the potential was there. So to actually see and explore this potential I have experimented with adapted 35mm lenses so that I can get a good idea not just a theoretical idea of what I can expect.

Both lenses used in this test were designed for different cameras than the EOS series, and so need adaptors. The OM lens was made for a camera with a shorter flange distance than the EOS, but not by much. So it only has a slim adaptor. The FD being used on the micro4/3 however has a much longer adaptor because (again) the flange distance effects the design of the lens (has to clear that moving mirror).

Paradoxically the 50mm lens actually becomes bigger than the 100mm lens when both are on their respective adaptors.

Of course a 50mm lens does not need to have such a massive stand off on a camera without a mirror. In this photo I show the Pentax 50mm lens (far right) beside the 50mm OM lens (on adaptor).

pentax-110-kit


So the new micro4/3 Olympus 45mm f1.8 is likely to be about the same size as that little pentax lens. If you happen to be interested in more compact 50mm portrait lens than the FD 50mm f1.4 I suggest you consider the little Pentax. I have reviews on them here , here and (perhaps the most interesting) here.

Of course adapted lenses lose "niceties" such as Autofocus, Face Recogntion Autofocus, auto aperture and a few other things which can be important (for people who don't know how to focus a camera or set an aperture). Since that time lenses have begun to emerge which don't cost an arm and a leg, may give better image quality and provide all the creature comforts (crutches?) for the photographer who needs them. For what its worth adapted manual focus 35mm lenses cost about ¼ of what one would pay for a modern equivalent.

However there is more interesting information available in this comparison yet. While the depth of field may be reasonably equal in a gross comparison there are some significant differences.
  • The 100mm at f2.8 has a more shallow depth of field at the subject


With both images I tried to focus on the back edge of the cap. Using the magnify zoom focus assist on the GH1 it was easy to get that spot. Looking carefully its clear that the 50mm lens on the 4/3 the focus zone is much deeper even at f1.4. By the distance from the ear to the eyelashes, they are starting to go out of focus on the 100mm at f2.8 but not on the 50mm at f1.4. This means also that you won't get that on the Olympus 45 f1.8 either.

This (shallow DoF) is exactly what one wants in a classic portrait lens.

The ability to have focus sharp and defined on the eyes
(my wife wanted to keep a little more privacy) but be soft by the ears or the back of the head, especially when the head is turned slightly.

Before people mention anything about pixel peeping, this sort of thing will become obvious on a 8x13 print and more so on a larger photo. Even if you don't "see it" obviously here it will be what makes it "feel better" when you examine prints.

This is not to say that the micro4/3 is bad by any stretch of the imagination. Indeed its pretty bloody good.

While playing around with these images I noticed something else, and that was the 5D also had a better dynamic range. You'll notice that the blacks in the shadows were better resolved? Thats because they had less 'noise' (as well as not being covered up by the flare)



The above are both taken at f2.8 (*where the FD lens became quite equal to the OM), the details in the shadow (arrows) are present on the 5D (right hand) while being muddy on the GH1. At the same time the highlight transition to washout (elipse) was similar. See the differences in the hair clarity in the shadows? If you were trying to dig a little into the image to pull out more shadow detail then the micro4/3 would give you a little less clear shadow detail than you'd get out of the 5D.

Lastly I thought I'd present the difference that one gets using a camera like the 5D in terms of outright printable size. The 5D image is slightly more pixels wide (4368 vs 4000), so if you were wanting to keep the aspect ratio at 3/2 then you'll get a slightly bigger print from the 5D, so printing at 300dpi from native:
  • 14 inches wide at native pixels on the 5D
  • 13 inches wide at native pixels on the GH1
Which is not exactly startling is it. On the plus side the 5D will tolerate more enlargement of pixels (upsizing) from native because it has a slightly better image quality (as identified above) and has a bit more to start with. In my comparisons above I've scaled the 5D back to the 4000 pixels of the GH1 so as to make it easier to compare. Here is the actual pixel comparison from these images.


So there is a minor increase in size of features in the picture, but personally I feel that if you wanted to print BIG or you want to capture every last skeric of detail then the 5D would do it that bit better.

Ultimately my call here is that the micro4/3 gives you 95% of the image feel and 99% of the image quality that a 5D will give. If the pursuit of that few percent advantage is worth doubling your money in buying a camera (and lenses)

PS: and now, after a long delay Part II is completed (sorry about the delays but some times life gets in the way)

Thursday, 20 October 2011

spinning and propagating bullshit

One of the thing I have never understood is why it's so easy to get bullshit past most of the people for enough of the time that it stands. It has been said "never attribute to malice what can be explained adequately by stupidity"; which makes me wonder if most people actually swallow it or if the media just shovels it.

My case in point comes from this article in the ABC news where the waterways on the Gold Coast were rated as having extremely poor water quality. When this was put to the mayor his response was:
"it's as much the lack of rain as it is the new development, I believe," he said.

Well you know, isn't it funny that this year has been about the wettest year the area has had for decades.

loganGolfCourseWaterTrapsWe have had flooding and strong rains even in the dry season. The journalist didn't pull him up on that, and it just gets said as if its true. It seems that noone has the capacity to examine the answer they get and just accept it: "oh well then"

This is not an isolated incident; with politicians, company executives and community leaders often pulling a fish out of their arse to answer questions.

This is of course why I could never succeed in politics, because when asked a question I answer it as best I can. It seems that all our leaders are adept at pulling out some distracting bit of bullshit which preferably bears only a passing resemblance to answering the question.

So my question is: is this because people are stupid (and swallow anything), people don't think and only after go "oh hey..." (sort of related to stupid) or because both the leaders and the media collude to put any old shit up as the justification for problems and to allow them to continue?

Which takes me back to my previous statement at the start of this:
"never attribute to malice what can be explained adequately by stupidity"

hmm ...

In my own life I'm often agape at the complete nonsense people seem to believe and the lame ass explanations they have for phenomenon.

Dad worked as a salesman and owned and operated his own businesses. During my school holidays I'd naturally be press-ganged into helping the family business. About the only thing I didn't like was hearing his same old stories said to each customer and the same old micron-thin flattery and ass kissing when we went into each client location. I'd groan and not want anything to do with it.

I realised later that this was because I saw this as a pathetic attempt to suck up, and expected people to be a wake up to that and (rightly) be a bit insulted at being treated like idiots.

The thing is that in the main, they never did.

This lead me to wonder at just how much shit you could get away with. You can toss off answers to valid questions and get an "ohh .. well then" response that indicates people have been satisfied.

I'd just shake my head and wonder what the bloody hell was wrong with people, can't you see that you asked about X and got an answer of something totally unrelated? I would wonder what was wrong with their logic.

As I grew older (and more experienced, though perhaps not yet wiser) I came to think that there was a few likely explanations for this:
  1. people are genuinely thick and have simply memorized the question (perhaps having been furnished with a few "trick questions" by a wiser friend but not having any clue what it meant that any answer would do
  2. people's attention span was so incredibly short that they forgot the question and just "looked up to the salesman as someone who knows" and nod in agreement as he hands down the tablets of stone
  3. none of it meant anything to do with logic and it was some sort of ritual joust and it was the speed of the riposte which indicated who won (irrespective of accuracy)

So I wonder about just how much planning and forethought really goes into things and how much is just "do what makes the powerful more powerful and the majority can play with their toys".

Back when we had
  • a world population of under a billion and
  • much lower demands on resources
  • much less impact on the environment from our actions
  • less dependency on our systems to survive
I suspect that it didn't matter as much but today I don't think we have such elasticity in our systems to tolerate much of a muck up without lots of people (millions) being impacted. Looking at how our leadership operates and the demands of accuracy and effectiveness that the public seem to have on them I reckon that it'll take a big catastrophy to change things.

even then I'm not sure it'll be any change, as has been said before
"plus ça change, plus c'est la même chose" [the more it changes, the more it's the same thing]
Jean-Baptiste Alphonse Karr

Tuesday, 18 October 2011

people have too much money

I know they'll scream that this is wrong, but how else can you explain that someone would be willing to pay $40,000 for a car and then accept loosing over $20,000 in three years?



no wonder people don't give a shit about the price of fuel, depreciation is so costly as to make fuel irrelevant.

There's something really wrong with this picture

Sunday, 16 October 2011

Olympus 21mm f3.5 on full frame digital

My first SLR was an OM1 and so my early years in 35mm photography were shaped by the compact systems that Olympus once made.

The subject of this blog post is the Olympus 21mm f3.5 lens. At 21mm it is a very desirable focal length for landscape wides, architecture interiors and indeed quite a number of photographic uses. Both it and the 21mm f2 are still famed for their sharpness within that focal length.

background

But the 21mm is not just a great tool for making images, its a great tool to use. Smooth to operate and light on the camera it feels as nice to use as the images you can make with it.

Pictured here beside my EOS 24mm f2.8 it is snug enough to slip into a pocket. The EOS lens operates nicely in AF mode, but if you want to operate manually that focus ring is just dreadful.

When it came to digital I was perhaps on of the early adopters. Digital cameras such as the Coolpix and IXUS cameras gave me better versatility and snapshots than any of the compact 35mm cameras could produce. At the time I never really thought I'd replace my 35mm camera with one of these digital things. Not because of any "better or worse" concepts, but simply because they did different things.

For me full frame digital has been one of the destinations of digital cameras since the first DSLR was introduced. For one reason of another I've never made the "commitment" and bought a full frame camera. The steep price tag however has always kept me at bay. So as a result I have never been able to answer an important question.

Is full frame worth the commitment?

I happen to like wide angle lenses, and as it happens shallow depth of field is something I like to take advantage of to make my subjects stand out from the background.

This image of the tree on the sand dune was taken with 35mm film and a 24mm lens at f2.8

I know from experience that had I used an APS DSLR for this image (such as my 20D) then the background would not be as distinct from the subject and everything would be more or less in focus.

So while I've had wide lenses such as my Tokina 12-24mm lens on my EOS 10 and 20D cameras there was always something missing for me.

Since getting my 21mm Oly I have not had a chance to use it on a full frame camera such as the Canon 5D. So this weekend I got to borrow a 5D from a mate (thanks Al) to allow me to think this through more and to also give me the opportunity to do some image testing on the Olympus 21mm f3.5, something which it seems there is not much of on the internet.

I took a few images in the back yard getting a feel for the lens and found that it was staggeringly soft in the corners. I only took one image at f3.5 and so I wanted to do something a little more through for a blog entry. So today we had fine weather (and I had some time) so I took my tripod off to the park and took some shots. So, lets look at the overviews of the two scenes I took today (at about midday) with the 21 on the 5D.

All images were taken with manual exposure, using exposure determined by my Gossen lightmeter. Naturally as I stepped aperture I also stepped shutter to compensate.

Image 1
In this image I focused on the building in the background. Below is a contact sheet made from the exposures starting with f3.5 on the LHS and moving to f16 on the RHS.

its pretty clear that at f3.5 there is some significant vignetting.


Image 2
where I tried to focus carefully on that middle green tree. Clearly with a 21mm lens once you focus on anything more than 3 meters from you its more or less the same as infinity.

The contact sheet.

The vignetting is (of course) strongest at the corners, but even at the middle edge of the frame its enough to be annoying at less than f5.6


Vignetting
As I mentioned above the vignetting at f3.5 was significant, so from Image 2 I've taken the left hand edge to show this. Not only is the image significantly darker but colour and contrast suffers somewhat too. Click on this image to load a 100% screen grab.


Sharpness
The middle of the image is unaffected, these are some from the center of image 1


so even at f3.5 if your subject is in the middle (as in my dune tree above) then it may not be a strong problem for you.

Corners predictably fall off badly, this is the lower left corner ...

and this is the upper right corner.



Click on this image and have a careful look at not only the sky density but also the definition of the building (well not that its not clear even at this size).

All of which leaves me feeling a little out to sea. I know from previous testing of this exact lens on 35mm film (both neg and slide) that I didn't see such stark and obvious vignetting or sharpness fall off. For example on this blog post where checked out this lens (using film) against the 9-18mm zoom on my 4/3 sensor digital camera. And again here.

So for those of you who may have been interested in obtaining one of these lenses (the Olympus 21mm f3.5) for use on full frame digital I can say it does an excellent job at f5.6 and smaller aperture, but just be prepared for some softness at f3.5 ... with foreground detail it can be quite a strong effect too. Click this image for a larger version to see what I mean (look in the branches of the tree in the right foreground).



This is the image which started me off checking the lens in more detail. If you look at the grass in the lower left of the image above, that's essentially in the out of focus foreground. So, if you like that look, then great, but you should be aware of if before you go get one.

conclusions?


Well now I feel stuck. This now has me thinking that for ultra wide lenses I'm actually going to be better served in staying with 4/3 (or in my case micro 4/3) while my previous experience with the larger full frame (on film) had me feeling that this lens gives better shallow renderings and being able to work at f3.5 higher effective shutter speeds (at a given ISO) than the Olympus f4~5.6 which is designed for 4/3 (and which is my other contender as a wide lens for my digital setup)

Right now I'm feeling more shakey about buying a Canon 5D than I have ever been.

The lens on film makes great images ...






its just that I don't normally use 35mm film much these days.

Perhaps I should?

pave paradise

put up a high rise lot ..

Ahh ... the Goldie, despite the fantasy propaganda of luscious beaches where you can relax with your family, the mass construction cancer is spreading. So you're likely to see stuff like this unless you have tunnel vision
Construction

it doesn't take a genius to realise that with all this highrise right next to the beach that its not going to be the cliche empty beach with just you and your family.

Friday, 14 October 2011

living in my letter box

Part of living near tropical areas is that much more lives around your house.

sometimes things take advantage of small sheltered spaces ... like letter boxes



with all the wet we've been having it seems that a Green Tree Frog has adopted my letterbox as a new home



he's so cute, and he comes out to hunt at night

Baltic Humor

I noticed when coming back to Australia that we have an entirely different sense of humor here. I suspect its a combination of "unnecessary Victorianism" blended with the American cocktail of "liberated" + "deeply stifled".

A classic for instance is this alcoholic "party drink" called popsy. We bought it on a trip to Tallin from Helsinki.

It looks rather like a sperm ... doesn't it


and incase you were uncertain of that the nice little logo reminds you



so, is it trying to get you in the mood, or is it just a warning?

Can't imagine them being popular here ... despite the fact that its popular here.