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onsdag 27. oktober 2010


Time for a blogg-deck: a links page or what we used to call affectionately, a jump station to my E450 bloggs and some external links if you have come here by Google/Yahoo.

Sample Images on the olympus E-450 : all web optimised, small/ medium 72ppi. Also see this blogg









Functionality on the E450: Bracketing Exposures; Using spot metering ; general settings and tips




What is Image Quality ?....Getting Better Results on the E450




Night Photography



Equivalency to the mrk 1 Human Eye in Focal Legnth and Field of view


Simulating a Blurred Background: The GIMP does Bokeh


External Links:

A very objective review , giving conclusions here

Olympus Europe Page on the E450

Using Manual Legacy Lenses from the Zuiko OM range biofos by John Foster

DP digirtal preview's forum for Olympus
E5 wannabees, sorry Olympus users with cameras in their hands.

Four Thirds User UK oriented forum

Dynamic Range, IQ and Tonal Depth Explained ( Olympus E450 owners)

Jargon Busting!

DR: Dynamic range. Seen a histogram? This is worth delving into on your camera display and at least on Olympus viewer on your PC. It relates very firmly to the actual digital data and the quality of the capture of the scene.

IQ No, your camera is not getting more intelligent, this is just a good old subjective reference "Image Quality"

Tonal Depth: this is just as important as dynamic range: given a hue or short range of light intensity, this is how many tones can be captured (and displayed!) such that the nuances of colour and shadow over shapes, textures and colour gradients like a sunse, add to the perception of quality and the technical accuracy of the shot..

How to Define Image Quality?

Well beauty is in the eye of the beholder and you could say therefore there is a dichotomy between technical accuracy and æsthetic value:

Most shots on the Dp forum showing Olympus DR etc are very dull subjects: standard test cards, studio objects or just desk foibles and views up the street from the office or shop with the new E5 on test!

However given some form of interesting content then you can say that the key contributors to image quality are:

1) representation of the scene in either true-to the eye or, a one that gives some æsthetic which impresses at first glance.

2) sharpness : usually the subject of the photo should be sharp: and when enlarged detail remains sharp, although this is a technical sharp: see the debate on how many mpx . I like many slightly blurry portraits - it is one of my own styles. Shaprness acheived by appropriate shutter speed, tripod, image stabilisation, correct focus and associated aperture mediated DOF:

3) Appropriate Depth of Field: the subject is either the only area which is represented sharp or the whole image is sharp ( by in large these two are what is regarded as contributing to good IQ.) DOF is a whole blogg on its own and can be mimicked in image software like gimp.

4) Accurate capture of shadows and highlights. The range apparent to the eye or a range which represents some æesthetic in the image.

5) A good representation of the colours and tonal depth of those colours across their hues and light intensities in the range between the white highlights and black shadows.

Rocket Surgeons Versus Picasso De Vanci

I guess the arguement could rage between the "technicians" and the "artists" on what IQ really is, but as in a previous blog on what makes a good picture, there are both technical elements and æsthetics which you could get rated by 1000 people and come up with an IQ rating if you must.

Certainly a good technical image will lend itself to representing the scene as intended or being worked up in after effects to a new æsthetic which may have been limited if the technical qualities were not there.

My favourite portrait photographers, including Anton Cobijn - the Joy Division and U2 image man, have often rather poor technical prints: very short DR, grainyness, blur, innapporpriate DOF , underexposure. However to me they are really striking.

Way Back When....

In the old days of film, given you had a reasonably good camera, there were two main areas affectting the quality of your colour prints.

1)IThe film as bought: how good the film was relative to its' ISO. it's colour "hue" representation, tonal depth and most of all the grain and noise.

2) At the Lab: The quality of the developing of the film ; the accuracey of the test exposure meter/print; the quality of the paper and chemicals, and the freshness of both.

Now we can't blame it on the lab or the shop or the film maker!

We have responsibility for the quality of our images, but it is luckily much easier : especially with Olympus which has such a good JPEG rendering engine and actually RAW files which are sensibly worked up from the totally raw data. Unlike some camera makes, you start with a reasonably sharpened ORF with a little more sharpening on the JPEG.

The 400 series do not have the absolute best DR and Tonal depth but for the price the overall image quality even with the so called "kit" lenses, is really stunning.

What is dynamic range and how do I see it in an image?

Well you see it most immediately in the histogram as mentioned, but wait up: take a look at the image and the exposure just after you have taken it, and compare it to what the eye sees. Try and alter exposure and focus until you capture near to what the eye sees.

Now look into the shadows and highlights of the image: there is a function in "INFO" which displays highlights and shadows ( I believe it is above 251 and below 5 respectively, more on numbers later.)

The key to understanding DR is that it describes these two extremes: what the camera can pick up in nuances before shadows become black and highlights become white.

Another related issue which is unfortunetly prominent in some conditions and exposures on the E450, is that in being devoid of nuances at the highlight or shadow end, flecks of noise, usually reddish, creep in. More on noise later.


Dynamic range is defined in digital terms as the range from 0 to 255, with 0 being pure black on the left of the histogram or curve (graph) and white highlight being 255 on the right. In black and white, everything in between is a shade of gray in a BW image for example.

Some cameras do not acheive a complete capture of this possible range: they will therefore lose some tones into being just black or white : so for example 250 upwards or 10 downwards. Also some exposures in the E450 will not capture the range: this would be under or over exposed for the situation.

Finally relating to this last point, some subjects or scenes either lack light intensities from the whole range: high key/ low key , or sometimes the sun is just too strong for the camera to "find" grades in tones from about 240 upwards. The same is true in very dark images, where there is not enough light / long enough exposure to give any detail in the shadows.

The relative proportions of image area which are captured in the image are then shown as the peaks on the y axis.

To capture the very best dynamic range for the conditions on the E450, I recommend using bracketed shots on programm or shutter priority, such that the aperture setting is changed. Further to this, if you want to capture the best exposure and "local" dynamic range for a given subject within the fram, like a face in a crowd, or a bird in a shaft of sunlight, then use the spot meter function. The camera will then interpret only the correct exposure and DR for that small area of the shot. ( see earlier blog)

Tonal Depth

This is actually not justt the y axis of the histogram : it is more the accurate representation of the spectrum of colours and their light intensity or saturation.

Shadows are black? Well many argue they are blue tinged, brown or infact grey and not pure black. But at first glance , total shadow point of below 5 on the scale will appear black to the eye.

The whole thing is easier to understand in the LAB system of colour separations than in the monitor oriented RGB scale. In RGB all the colours combine : all off, "0" black, all on 100% light intensity, 255 white. In LAB the blue-yellow and red-green primary range are separated and represented as the opposiste they actually are: where there is yellow, there can be no blue!

The third channel is pure BW, grey scale. In LAB you get a better idea of shadows and highlight areas, and how this helps add depth to an image, while you also have a better level of control in colour balance ( a whole other topic!)

It can be worth converting to the LAB system to work up some images: especially high key and low key, or subtle tonal range images and then finally converting back to RGB JPEG at the end. Nearly all monitors are RGB so you see what you are going to acheive when the "separations" are viewed together.

Why is Tonal Range Important to Me?

What you can do is refer to books which discuss and illustrate "polarisation". This shows how good tonal range is necessary to help with depth and sharpness in a pciture and perception of good image quality. You can reproduce it by super compressing a JPEG at a small size at 50 ppi. Save a copy of a portait ( face only) and then repopen it to see the poor quality and then look at the historgram.

There are large areas of the histogram with zero values: colours become clustered into individual peaks and there is an appearance of "super pixelisation" , box like areas of single colour. There is a sharp grading between colour or shadow areas, with contours often appearing on faces like some maps and weather charts!

Think about making this gradually better, in more detail , and then you start to realise that tonal depth is important for representing a 3D scene. Also it is important for displaying hues and saturations of colours across the historgram. The graph would have more peaks and a rounder curve between peaks given sublte grades of colours, such as in skin tones or fabrics with light coming from a low sun for example.

fredag 22. oktober 2010

A Thanks to Olympus ...even if I am a non profit customer!

I have had the Olympus E450 since late january and am enjoying photography like never before.

Like many I had been a previous SLR owner and Olypmus OM user from the 1980s, moving over to 35mm super zoom ( pentax W90 135) and then a couple of 2 to 5 mpx compacts while other budgets were met long before a 5D EOS or Nikosillycash.

Now I would like to thank Olympus for making a quality, compact sized DSLR within my reach and making photography once again a big hobby of mine.

At the moment the Olympus E450 is a steal from many internet and chain stockests because it is being heavily discounted, often to under 400€ with the kit lens 14-42 f3.5-5.6.

This is rather fortuitous that a whole new group of owners can enjoy some of the plethora of features, which would on a 35mm film SLR make this a top pro model for the late 80s, at a price less than the non-veiw finder PEN cameras from Olympus. Other blogs rate the E450 very highly and some pros are using it even as a back up body, now it is revealed it has the version III image engine also carried in higher models.

In general, given bright conditions the camera takes great, sharp images with a level of control over depth of field which would be a familiarity to someone in 1985 with Ektachrome 64 asa or a 100 asa film ( ISO now). As soon as it get's dull, you need the faster prime lenses and to start pushing the ISO or using a tripod. So you could say the camera is lacking the image stabilisation or high ISO performance without unacceptable noise. However , you could save at least 500€ by knowing what good conditions for great photos are, using a tripod and furthermore, appeciating the limitations of your camera.

All these shots have been taken in the last day, with unexpectedly heavy and lying snow !

One petal left, but no.one has told the flower's that it is winter.....

( not a clear due to the trees, I was waiting for the AIr Ambulance to take off again and run a 10 second exposure on it or get the rotors in motion with a still body; but this is just sharpened 20% and reduced in size, demonstrating the DR of the camera at 25sec f22, and the manual focus using the maginfy in Live View)

Quite good DR on a difficult exposure I should have bracketed: my favourite feature. THis is from RAW ORF file, sharpened. The apparent noise on the petals is acutally the structure of the plant creating a "Pixel" effect, with whiter blocks. Focusing in such soft light was an issue, and this shot really needs a tripof and f11 to get the correct sharpness and DOF.

I see all too many E3 or Nikon 5D shots which are boring, poorly composed and not even in control of an interesting DOF. The aboive shots are a

However this nice pricing and the availability of the three of four entry level lenses is actually not a locking in strategy to capture new users nto the 4-3rds ladder: the ladder is clearly cut off now with just the top "pro" E5 ( a wannabees camera) . A micro four thirds camera which may suit the current 4-3s full sized lenses is a bone Olympus has thrown to the press and users.

To some extent, I don¨'t care! I would invest in a faster prime and maybe one more zoom with some smaller f numbers before I would upgrade the body. I have apparently, a longer product ownership lifetime (personal lifecycle) than most in the gnats-brain-attention span of the generation X's and "i"s have.

Olympus have basically stated that if you want entry level, then put up with no built in VF and slower lenses in both f Stop and AF on the live-veiw only PEN system. Also you will pay for the priveledge fo having something smaller and less SLR user friendly! So I am not worth enough to Olympus now and they are not worth enough to me when I come to upgrade body. Lose Lose it is called in game theory!

I think this is probably throwing in the towel for Olympus to both discount off their entry level, ultra compact DSLR and look for higher margins in the compact "system" or "Hybrid" camera sector.

lørdag 9. oktober 2010

The E450 on carrots.....night vision

The four thirds system has had some comments for noise and slow ISO: this seems to be being beaten down with the qualities of the E5 and the panasonic range in muFT.

But here are some interesting shots

1) daytime scene from my friends balcony, taken with a hang over. Note the colours, boring photo taken because

2) this was the image as close to as the eye-saw-it, while we were out getting some air and red wine late in the evening the night before. This is nearly the end of dusk on an early October evening some weeks ago.

2"/f5.0/16mm(=32)/ISO100/Natural Colours

3) and here is what the E450 managed on MF and a long shutter speed: unbeleiveable colour and quite low noise: the image is out of focus flatly because neither the AF or the Human Eye Mrk1 had anything to focus on!

4"/f3.7/16mm/ISO400/Natural Colour

NOTE: This seems to be a good setting on the camera for nearly dark, but just enough light for the naked eye to see some detail and maybe some colour.: However it is better to secure more of the scene in focus than the MF will be able to do by setting a very high f stop like 22, and seeing what the camera says in Manual or P modes. The lower f stop may give the same exposure but I would expect the colours to be poorer.

Here are some more evening shots: ( wood on wood, loft lighting, the tower etc) surprising adjustments to the bracketing, worth setting out with a wide +/1 on Aperture prio' so to estbalish your depth of field and then just let more or less light in on exposure time. P often get's it wrong. I had left Spot AE on by accident.


AperturePrio/15/f14/114mm(228)/+0.7/ISO400/Natural colour/WB Auto

100mm(200)/25" f22 Iso 100. From RAW ORF, just some sharpening: very impressive DR, could have been better focused or on a heavier tripod

fredag 8. oktober 2010

Meter Experiments with the Olympus E-450

The Olympus E450 continues to suprise me with the qaulity of it's various technical functions and the so called "budget" lens range of which I have three. As mentioned in the last blog I often use bracketed exposures onto a centre weighted auto exposure
In this series of almost identical content, I have only varied the camera's settings to produce very diverse look and feel for the images.

I started out with ordinary focus three points, and centre weighted auto exposure ( AE) I then went to two types of spot AE and down the spot AF to get the leaves in subject really on their own as it tirned out!

In these images the WB was set to auto, but it could have been tried with shadow or sun to experiment:: colours were natural, VIVID could have been too saturated and bright.

6904 ...42mm( =84@35mmFF camera) .80th/f5.6 ISO 400, Exp 0.0

Not a bad shot, nice hightlight on the leaves, a bit heavy contrast, but good depth / figure separation : a bit cluttered with bckgroung and other leaves in the same plane as the lit up one.

Shows why I wanted to experiment further:; this was a little brighter to the naked eye


6905: 42mm( =84@35mmFF camera) A (ap'priority) 80th/f5.6 -0.7 ISO 200 Spot focus highlight natural colours WB auto'

Just dumping fown one exposure on the camera dn going for highligh, mnakes the leaf instandtly stand out whiel the backgorund is more thrown in focus, darker while still interesting and not now a distraction but a reference for the eye

6906 as per 05 but 60th +0.7 ISO400

This if I remember right, is the closest to the naked eye because the leaf was super illuminated by a shaft of sunlight against the cliff backdrop and other shadows of trees to the left.

The saturation and brightness of the background is differnet from 04, for better or for æsthetically worse

.... .....9707 42mm/800th/f5.6 ISO 100 O.O Spot AE

The scene now takes on a ghostly moonlight apperance, with sharpeness in the detail around the main subjects, and a better attention grab for the three leaf sets.

9708 1250th/ -0.7 Spot Focus and AE

With the stop donw on auto bracket on the spot AE , this shot now is most definetly in the night vision category despite being taken in daylight. INteresting colours.

6909 500th Spot SH and Spot Focus

I will have to read up on Spot SH but in this case it really worked Once again a ghostly moonlight feel , but the best of the three darker.
Spot focus helps the image here too.

Hope i have the ORF file!!!

mandag 4. oktober 2010

It all Hinges on the Bracket

There were two key things which were lacking on almost all compact zoom digital cameras: RAW file format and the Bracketed shot <<>> function. Now both are on the Olympus PENs but instead of saving a couple more months, carpe deum on a sub €400 eruo deal on the E450.

Bracketing used to be a manual operation in stepping usually just the aperture up and down one or more f stops around a presumed best fstop. Later it was introduced on 135 format ( 35mm) cameras when they went electronic and motordrive in particular.

Some cameras had a plus/minus exposure button, and this has become very popular on digital SLRs, allowing you to quickly toggle or wheel up-down the exposure one step or in fractions.

Any DSLR worth its' salt will now have a BKT function with atleast three steps ( - /0/ +) at definable increments or fractions of exposure steps. The E-450 fits the bill here

The following little sequence makes me very glad I didn't buy an LCD based experience, but rather a through-the-lens view because they were almost into the sun and it was a very, very bright day with little humidity in the air.

P ...87 94 mm( 188 mm on 135/ FF) 320/f5.6 0.0 / ISO 100/ VIVIV/ Centre Weighted AE

Base shot, first out; maybe a bit over exposed on the highlights, which the 400 series seem to handle quiter poorly : making white blocks with noise often.

P 88 94 mm 400/f6.3 -0.7

The leaves here have a nice saturation, but the shadows become heavy. Also the "corona" highlight on the leaf-edges is not noticeable.

P ...89 +0.7 250 / f5

Still a nice shot, the shadows now have full colour, while this fights with the vein detail in the leaves. THe leaves are a little washed out

This was infact, perhaps the nearest visual perception of the very brigh light, while the eye still sees colour in the shadows.

90 P ....90 zerio compensation 250 f 5.6

A little flat, in between saturated and not.

P ...91 320 f.6.3 -0.7 WINNER IS.....

The shadows are a little heavy, but a good balance between saturation and detail in the leaves: also, when cropped as in the top of the blog, the corona on the leaves is very evident and ...competition winning.

P....92 200 f 5 iso 100 vivid 86 mm ( 40-150) +0.7 Exp Comp / Centre weighted metering

Small Tips on Using the Olympus E450 DSLR

Now the E450 is seen as an entry level camera, but if you are like me a previous 1980s OM and manual camera user, then its' features are from outerspace:

So there are probably many, many useful or just mildly interesting functions which never get used by today's buyers of such a so called entry level little gem!

However, some default settings are really not ideal. Furthermore some settings are highly desirable when you get "that" shot situation you want to get right.

I've had the camera 8 months now: here are some tips / observations:

There are some odd defaults: vivid colour is just too much for me, natural is really true with muted being a little "ektachrome" in feel. Portrait colour seems a bit strange, but I have actually just discovered monotone on bracketed shots gives very good results Prog/ AUTO selects a slower shutter speed than I like to use, often under 250 and f8.
I set colour over to natural, centre weighted AE, and AF with three points, set fill flash on but deactivate auto pop up and am careful to check Prog is fast enough. Then the flash is always ready to fire just by hitting the hard button on the top.

Also I leave the braket function on, "toggeling" it's use with the frame shooting button and the exposure adjust in front of the shutter release. In other words on single shot you just quickly adjust to zero on the little front button, while as soon as you want brakceted shots , just switch the frames button on the top.

Sports mode is okay to secure the fastest available exp' for the light, but does not function with bracket and the continuous auto focus on live view is not fast neough for sports!

Fireworks effects does a damn good job, better than I could achieve, as does candle, night portrait and to some extent the virtual macro functions.

Night shots on a tripod : MF all the time, f8 and 15 seconds for say 20% of the scene having street/house lights or 22 for less light/ softer light; use the mirror delay function for this too.

Before you shut down! Another little tip is that the camera seems to use less power if you leave it on during a 2 to three hour period of sporadic shooting: ie boot up takes battery power. NB! Switch off live view and check it is been accidentally put on. It uses more power even with the lens cap on!