Nikon D40 high ISO test

Introduction and ConclusionThe purpose of this test was to see what degredation of the image would be caused by using high ISO settings on the camera. My conclusion is that even the highest ISO settings are useable, and certainly 800ISO can be used as a matter of course, without worrying about degradation of the image.

My long-time experience is that plenty of light thrown on the subject also helps – so very low light shots may well still show chroma and luminance noise in deep shadows.

Which begs the question of why use high ISO if there is plenty of light about? The answer is that higher ISO enables higher speeds to be used, which is great for moving subjects; and a high ISO sharp shot is always better than a low ISO clean file, but blurred, shot.

A note on ISO
For those not familiar with the term ‘ISO’, it is a measurement of the camera’s sensor sensitivity to light. The higher the number, the greater the sensitivity. The term is a holdover from film cameras. Each film is made with a specific sensitivity.

As there is a relationship between the sensitivity of the film, the shutter speed and the aperture that can be used in a given situation, photographers are always looking for the optimum combination that will give them the best image quality. With film, the greater the sensitivity, the higher the shutter speed that can be used, as less light is needed to burn the image into the film.

But higher sensitivity comes at a cost and the cost is the increasing appearance of grain in the image. The particles or (or dye clouds in the case of colour film) become more visible, the greater the sensitivity of the film.

But what about digital cameras, which have no film? Surely they always have the same sensitivity, after all there is no film and it is always the same camera? Well, increasing the ISO in a digital camera is apparently a matter of increasing the sensitivity of the the chip/circuitry. But as with film there is a downside, which is that in the ratio of the signal to noise, there is more noise (the digital equivalent to grain) compared to the signal.

Or rather, in this fast-moving digital world, the downside is becoming less of an issue as time goes on. For the detailed results – read on.

The Results
I shot these images in RAW and opened them in Photoshop CS2 with my default RAW conversion set-up, which has no sharpening, luminance smoothing, or colour noise reduction. Each image was then Saved-For-Web with no sharpening or colour correction.

The photographs were shot with the 18-55mm kit lens with the focal length set, according to the EXIF data, at 48mm.

The shots shown here are crops of a few hundred pixels from near the centre of the image. I set up a standard crop size for the crop tool in Photoshop and cropped each of the shots to the same number of pixels.

For comparison purposes, the first shot is taken with a Nikon D200 with a 50mm lens and set at 100ISO.

CLICK on any of the photos for a larger view.

D200 at 100ISO
d200-100iso.jpg

D40 at 200ISO (the lowest ISO setting for this camera)
d40-200iso.jpg

D40 at 400ISO
d40-400iso.jpg

D40 at 800ISO
d40-800iso.jpg

D40 at 1600ISO
d40-1600iso.jpg

D40 at Hi-1 (3200ISO equivalent)
d40-hi1iso.jpg

There is more detail in the shot from the D200, but that is to be expected given that it has a larger sensor and that the 50mm lens is probably sharper than the 18-55mm kit lens on the D40. Nonetheless I think it is clear from the shots that even the highest ISO is useable.

Of course, I want to know whether whatever differences there are between the shots, would be visible in a print. I read somewhere that looking at an on-screen shot at 25% gives a good approximation of what can – and cannot – be seen in a print. If that is so, then these crops are certainly a stringent enough test.

I have not printed these images. Some time ago though, I printed a portrait I took at 800ISO shot on the D200 with 105mm f2 DC lens (a very sharp lens) to 20×30 inches (45x150cm) and it looks as smooth as one would want. Or rather, it has an ever so slightly sketch-like look if one looks very close; which is how I have found that the D200 tends to render images at high ISO. For portraits it is very appealing.

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Adobe Photoshop CS3 – intel Mac version – first impressions

Bridge is much quicker and much, much more stable than in CS2. I hated Bridge in CS2; so much so that if I did not have it open I would sometimes rather go to file/open in Photoshop and trawl through the images in the folders on the computer, than go to Browse and watch the clunky Bridge program open and struggle.

All that is changed now with Bridge in CS3. Now it is a pleasure to use and let’s you get right on with finding what you want.

After 16 days use it has not crashed on me once. It has however told me on two occasions that it has quit unexpectedly, but on both occasions I had just closed the program. So whatever it said, it had not crashed at all, in fact. I have had that happen with Bridge CS2 also – strange bug.

It has a nice Preferences panel to set the background (from black to tones of grey to white) for the images and for the data, and for the highlighted folder. Very nice on the eye. And there is a nice crossover point where, if I set the background darker than a certain point, the text changes from black to white – a necessity otherwise the text would be invisible.

The layout and sizes of the panels (folders, thumbnails, large version, metadata etc) can be changed to suit, and and allows a nice big view of the chosen image.

Bridge does stacks, keywords, sorts, labels, and slideshows like Lightroom does, but it does not have all the output options (print, Web, batch process) that Lightroom has. So for batch processing jpeg images for print or to a website, there is still reason to have Lightroom.

Photoshop CS3, however, has a script that will batch-make jpegs, PSDs or TIFFs. And it will make a web photo gallery, though I have not compared its capabilities with what Lightroom will do.

How long will Photoshop/Bridge and Lightroom remain two separate programs though? The stated philosophy was that some photographers wanted to process and batch process images and did not need the capabilities of Photoshop. That may be so now, but I cannot help but think that CS4 will surely incorporate everything Lightroom can do.

Photoshop’s RAW converter is a huge improvement. I was never happy with the lack of controls in the RAW converter in CS2 and the need to think in terms of further operations in Photoshop ‘proper’. It always seemed to me to be a bodge of a way to deal with images and probably a hang-over from the architecture of earlier versions of the program.

Whatever the reason, in CS3 it is now possible to get an image how you want it in the RAW converter before you open it. There is everything you might want to do in terms of the production of the unretouched image. The capability that I find I am using more and more, is fine-tuning the tone curve. The tonal range is divided into four sections from highlights-lights-darks-shadows and each has a slider. Using these I can fine tune the appearance in a convincing way.

The other capability I find I am using, are the hue/saturation/luminance sliders. Using these I can make very fine adjustments to the colors.

olivia_002__061.jpg

Photoshop
Once opened, the changes in CS3 are more subtle. It is quicker but for many operations the extra speed is not so startling. The tool layout is tweaked but not so different.

But what is better are the additional things that are hidden ‘under the hood’ so to speak. The features don’t jump out at you and so I have been looking at Russell Brown’s videos. I recommend them highly – they all free, and made by a major contributor to Photoshop’s development.

for example, smart filters for text is a joy.

The Refine Edges palette option within the Quick Selection Tool are a visual pleasure and the tool itself uses a selection method that enables the user to teach the tool what to include within the selection.

The subtleties of the Clone Stamp tool are great because they are so visual. In fact that is the characteristic that best defines the improvements in and additions to the tools. They are visual – you can see what effect you are making before you commit to your settings.

As of now- a success.

Real-World Review of the Nikon D40

Lifta

Buying considerations and the Competition

I got fed up with the weight carrying my D200 around – even with a little 50mm lens – for those not-specifically-about-photography walkabouts.

So I read the reviews and pondered the Nikon D40 as well as the Canon EOS400D/Rebel Xti and Xt and small-sensor cameras, such as a Leica D-Lux3, or a Canon SD700, or G7, or A640, or A570IS, or S3-IS and I tried them all save the Leica and the Xt/Xti in a camera shop, and then read some more.

I read Ken Rockwell’s review of the D40 and if you are in the market for a small camera you would do well to read it (just Google Ken Rockwell D40).

Of course, Ken Rockwell is a firm proponent of shooting JPEGS exposed correctly and using the camera’s settings to maximise the shots the way he wants them.

But I shoot RAW and the number of shots I have post-processed that would have suffered had I shot in JPEG, keeps me wanting to shoot RAW if I can.

But I was prepared though to think of a JPEG-only camera if that was the only way to solve the weight problem, on the principle that a shot is better than no shot at all.

But when I thought about that a bit more, it seems to me that the proviso to this was that image quality and low shutter-lag would be priorities ranking high among my requirements.

But shutter lag and low image quality are a penalty I was not prepared to pay in order to have a lightweight camera.

Assuming I shot in JPEG, then things such as white balance could be altered in post processing, even if it meant losing some information. Of course shooting RAW all things can be changed, including the better part of two f-stops exposure.

Another thing that ranks high, is being able to see what I am aiming at. So, that put paid to some of the compacts, which had viewfinders like looking through tiny tunnels.

It was impossible to tell what was in focus, even though they did offer the ability to slip the camera in a pocket and take it everywhere.

But then some of the compacts offer in-built image stabilisation, which seems to be a clear advantage in favour of compacts. Well yes and no, because the image quality at 800 ISO from a larger chip camera such as the D40 might be as good as at 200 ISO from the smaller chip in a compact.

And at 800 ISO, image quality from all small-chip cameras falls apart.

I have a couple of older compacts, and image quality is not great even at 100 ISO.

One could not fit the D40 in a pocket but it is small. It weighs 522g (18.4 oz).

It is only marginally heavier than the Canon S3-IS, which is 510g (18 oz), just a mater of 12g or so. And the Canon seemed very cluttered with buttons.

The Canon G7 is lighter, at 380g (13.4 oz) and the view in the LCD display is very clear. It is not a nice camera to hold, however – heavy for a compact, and built like a slab.

I have seen JPEGs from a Canon G7 on-screen, and while good, they are not that good. So the gain from image stabilisation has to be considered against the high ISO capability of the D40, about which see below.

Decision Time

So with these things in mind, and bearing in mind the price of the D40 with kit lens, I found myself unable to say no to a camera that offered higher image quality, faster ‘ready-to-take-the-shot’ time, and the ability to shoot RAW.

But, whether the D40 was the answer depended first of all on its weight. Perhaps I needed to wait until the D*** in the year 2010? Yeah, sure.

Grip, fit and feel

I have a habit when I pick up a new camera of tipping and yawing it loosely around in my hands to get a feel for the balance point.

For anyone who has not handled a D40 I can tell you it is make of air.

It is so light, it floats. And with the kit 18-55 lens it balances excellently.

All the weight is in the middle of the mass and there is no feeling of torque pulling it away from my hands. Yet at the same time, the overall lightness means that the feeling of the weight being in the middle of the mass, does not make it feel brick-like or inmobile.

(You might want to read my review of the D200 in this blog for my thoughts on the weight and feel of that camera).

It is clear that a lot of thought has gone into the design to make it a working tool.
I am happy with the shape of the handgrip for the right hand, but it was not quite what I was expecting, especially after reading the review of the D40 in DPReview.

I don’t have large hands but my fingers bottom-out beyond the base of the handgrip.

I cannot sink my fingers right into the base of the handgrip and is rather like pinching the handgrip, compared to grasping the meatier handgrip of the D200.

So to hold the camera steady I have to to slip my little finger under the base of the camera and rest the bottom right of the body into the middle of my palm.

Using both hands, it is a pleasure to hold.

Shutter

The light weight of the camera would not be an unqualified advantage compared to a heavier camera though, if the shutter went ker-lunk and sent that nice little light camera skittering everywhere, but it doesn’t

The shutter is smooth and light as though there is not very much mechancial going on compared to the D200 which has a hard, final-sounding clack.

I assume the smaller sound of the D40 is is because the mirror box is so small, so there is not very much mass to move up and out of the way. Whatever the reason, the vibration is minimal.

Viewfinder

The downside of the smaller mirror box is the smaller view through the viewfinder. With the D200, I find myself looking around to find the edges and corners of the view through the viewfinder.

That’s not surprising because the viewfinder is about 15% bigger along each side than the D40.

But the viewfinder of the D40 is clear, bright and free of distortion and light-years ahead of the view through some of the compacts.

Autofocus areas

Some DSLRs have seven points of autofocus, some have eleven, some have many more. The D40 had three, in a line across the middle of the frame.

That’s not a downside for me because I almost always use the centre focus area whatever camera I am using.

Ny only wish for this camera is that the central area could be locked.

Instead the focus area can be moved using the paddle at the rear of the camera. The focus point only moves when you click on the left or centre or right of the paddle wheel, but it cannot be locked in any of those positions.

The relevant focus points light up when you click the paddle and it also light up when you focus.

But if one hits the paddle by mistake and don’t notice it, the focus point will have changed and the only feedback is when the focus points light up as one focuses.

In a rapidly developing scene such as a march or a demonstration, it is easy to lose track of focus points when so much is going on.

I have used other cameras without the centre focus area being locked, only to find that in the heat of shooting, I have not noticed that the active area is not the middle one, and hence the camera has been focusing other than where I wanted it to.

On a related point – with other cameras, when I have wanted to use a focus area other than the middle one, I have also wished that those focus areas were nearer the edge of the frame than they were. The D200 has five horizontal focus areas and the ones furthest to the side do seem to be nearer the edge of the frame than the outer two on the D40.

Of much more importance to me is how big that focus area is. I want it to be as small as possible so that I can home in on precisely where I want my focus point to be. My conclusion is that the focus area is within the focus area marks in the viewfinder – which is good news.

But, with small, near objects against a contrasty background, the autofocus may well find the background in preference, or not be able to find the near object. In fact it’s about as good as the D200, certainly not noticeably worse.

Information

There is no LCD on the top plate and the only downside of that for me is that I cannot see the ISO. But the info panel in the rear LCD comes up every time I turn the camera on, or at the touch of the ‘info’ button that is next to the shutter, and the panel is very clear. That panel shows ISO and all the other information one wants.

ISO

There is a function button to the left of the lens mount, that allows a variety of options to be assigned to it. I have assigned ISO to this, so with the info panel showing it is a simple matter to hit the function button and spin the rear dial (there is no front dial) at top right of the body, to whatever ISO I want.

Nor does the viewfinder show what mode the camera is in, but that does not bother me too much as I usually shoot in Aperture Priority.

About noise, and noise reduction – one thing that is clear and that is that having carried out simple real-world tests, photographs show that the benefits of a larger chip in the D40 easily compete with the benefits of image stabilisation in a compact. Now if the D40 had image stabilisation as well …

Using Exposure Compensation On The D40

On a bright day the contrast range across a typcial outdoor scene is large. And according to the review on the LCD, it is easy to blow out highlights with normal exposure.

I don’t mind tiny areas being blown out, but when large chunks of the scene go, it can ruin a shot. So its a clear advantage to be able to alter exposure easily. There are two ways to do this on this camera.

If there is a large enough area of light-tones in the scene, then meter off that area, press the AE-L/AF-L button on the top right of the body, and recompose. The AE-L/AF-L button can be programmed in menus to lock exposure or focus or both, so I have set it up to only lock exposure. That allows me to use the shutter button to refocus when I recompose.

Alternatively, there is a dedicated Exposure Compensation button just behind the shutter button. Hit this and the info-panel comes up in the LCD and also in the viewfinder.

Whichever you look at, spin the rear wheel to change the exposure compensation. It’s fast and easy to use.

If there is no exposure compensation dialed in then nothing shows in the viewfinder. If exposure compensation is dialed in then it shows all the time in the viewfinder. Each one third of a stop shows as a little bar along the scale, to the right of the centre of the scale if negative compensation is dialed in, and to the left of the centre point of positive compensation is dialed in.

Today I had a good taste of shooting in contrasty conditions. I dialed in -0.7 exposure compensation and was still blowing out highlight areas, according to the review in the LCD.

However, in Photoshop CS2 RAW converter, with exposure reduced by 0.35, those apparently blown and irrecoverable highlights show detail, and only a small area was irrecoverably blown.

So it seems that the flashing areas in ‘highlights’ mode in review in the LCD is more cautious than can be recovered in RAW.

The Kit Lens

The kit lens is good for the kinds of things that I intend the camera for, but it does suffer from noticeable colour fringing in highlight areas such as small branches against the sky.

It also shows that sketch-like quality in small detail that is the hallmark of a lens that does not have the bite of a top-class lens.

The camera has no internal motor to drive autofocus, so it can only autofocus with AF-S lenses, which have a motor built into the lens. I am quite happy to accept the restriction that the camera only accepts AF-S lenses in order to be able to autofocus.

Given the use to which I want to put the camera, I don’t think I will be be changing the lens anyway.

And I accept the restriction on lens quality for a camera that I have with me, against one that has better quality but stays at home because it is bulkier, or longer, or heavier, or does not autofocus on this camera.

What Is Lacking?

So what does the camera not have? Well it has a hotshoe, so it could fire a flash off-camera with a suitable sync cord and hotshoe adaptor, but it has no way to control off-camera flash with the master/remote flash controls that the D200 has that work with SB-800 (and SB-600) flashguns, so I shall not be selling my D200, all other considerations aside.

And no ISO showing in the viewfinder.

And it does not have a depth of field preview button, but I use the following rule of thumb:

wider-aperture-for-portraits, and f8-to-f11 when I want to ensure the best chance of getting a sharp shot of my subject in trickier conditions.

What Does It Have?

It uses the same little remote control that the D70 did. My D70 was stolen so it is nice to have something useful to do with the remote, which happened to be in another bag when my camera was stolen, and has been sitting there ever since, asking me what I was going to do with it.

It is very nice to rest the D40 on a table, point it in the direction of my intended shot and (first having set up the remote in menus) trigger the shutter with the remote.

Battery Life

Battery life is everything that battery life should be – it just goes on an on. I have had the camera for two weeks and in that time I have taken 200 shots – some with flash; reviewed them on the rear screen; played around with the menus to understand them and to set up the camera – and the battery indicator shows a full battery.

Compare that with the D200 where after a day’s shooting the battery indicator usually shows something around 55%.

I have never continued to run the D200 battery down but have popped in the second battery, so perhaps the D200 would go on for longer than the indicator ‘indicates’, but I am not going to experiment to find out.

The EN-EL9 battery on the D40 is smaller than the battery on the D200, so I cannot help but wonder what the reason is for the difference in performance.

I wonder whether it is the fact that it does not have to move the big mirror up and down? That seems to be the biggest mechanical job the camera has to do – that and move the lens focus mechanism.

Conclusion

The image quality is excellent, which is as expected given the processor and chip that are in the camera, and the small amount of vibration in the shutter means I can hand-hold shots at a lower speed than my unforgiving D200.

Shutter lag is non-existent and write speeds are as fast as I want.I have no interest in testing them as they are as fast as I need for what I shoot. The balance on the inbuilt flash is excellent for fill flash.

So after two weeks of carrying it around, and being able to dip into my bag and shoot without the weight penalty that can make one rue the day one took up photography rather than paper-folding, I can say the D40 is an unqualified success.

Postscript

Having just got home and had time to read more reviews of the 18-55 lens, I feel compelled to do some tests comparing it to the 18-70 and the 12-24, and a fast telephoto-length prime. I just put the 12-24 on the body and the weight and bulk of the lens makes the combination feel like the body is hanging on the lens rather than the lens being attached to the body.

Given the weight of the lens, if holding one-handed, it is probably wise to hold the lens rather than the body, to prevent the lens pulling the lens mount out of true.

I want to get these tests done, so watch this space.

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