Thursday, March 27, 2008

Which Digital SLR?

photographyThird in a series that gently explains digital photography and makes helpful recommendations.

In the last article in this series I explained why you should use a digital SLR if you are serious about photography. I am sure my convincing argument spurred you to check out what's available. And no doubt the first names you encountered were Canon and Nikon. Between them these two manufacturers have a huge share of the world market. Snapping at their heels are Olympus, Panasonic, Sony, Fuji and others. Read any other article of this sort on the net and nine times out of ten it'll recommend Canon or Nikon, simply because they are so pervasive. But life is not a popularity contest.

Less well known is a company that will nonetheless ring a bell for anyone who enjoyed photography back in film days. They were once the world's leading firm, and are still number three in their homeland of Japan. I speak, of course, of Pentax. Pentax offer the best value in digital SLRs for amateurs and semi-professionals, and here I'm going to tell you why you should consider them.

First, I should make it clear that any digital SLR offers all the advantages I elucidated previously. Any DSLR, in the right hands, can take astounding pictures. But nonetheless I believe some choices are better than others, even if the only place you'll notice is in your pocket-book. Buying a camera body buys you into an entire system of compatible lenses and accessories, so it pays to make the right choice the first time.

Pentax makes buying a camera body simple, since they have few models in production at a given time. Until recently these were the entry-level K100D Super (so called because it was a slight upgrade to the preceding K100D) and the higher-end K10D. Recently introduced are the upgraded K200D and K20D. Since you might still see some of the older models in stores there are effectively four body choices, but in this general discussion I'll stick to discussing the new ones.

(I should mention that the K20D is also available under the Samsung brand name as the GX-20. It's virtually identical to the Pentax, as are the lenses Samsung licenses.)

What are the notable features of these cameras?

First, they are weather-sealed to protect the innards from rain, dust, sand and other evil influences. Pentax makes the cheapest weather-sealed cameras in the world, and they are cheaper by a huge factor over the competition. A small line of professional weather-sealed lenses are also available. If you take photos in adverse conditions the choice of Pentax is simple.

Second, Pentax has image stabilisation built into the body of the camera. This means that every single lens you attach gains the benefit of from 1 to 4 stops of anti-shake. The traditional rule of thumb is that if you are not using a tripod to steady your shot you need to keep the shutter speed at least as fast as one over the focal length. For a 50mm lens this means 1/50 second. But with the K200D and K20D you can effectively hand hold the camera down to 1/10 second or even slower without blur. You can get sharp photos in low light conditions without a flash or tripod. This means you can be much more discreet in performances, gallery spaces, when taking candid street shots, and so on.

Other vendors build the image stabilisation into the lenses, so you need to purchase special (more expensive) lenses to gain similar benefits. With Pentax any old lens magically gets the anti-shake benefits. This is a huge advantage!

This brings us to the third key point. Every camera make has their own proprietary lens mount system. Annoying, but true. Pentax has used the so-called K-mount bayonet since 1975. With a simple adapter you can also mount M42 screw-on lenses. Time passes and technology changes, generally rendering much equipment obsolete. But here is the incredible thing. Pentax DSLRs can use any lens ever produced for the system!

If you find an old lens in a garage sale it will work with Pentax. If your uncle brought a lens home from communist Russia it will work with Pentax. If you have a significant investment in glass from the film era, all of it will work with the latest Pentax cameras.

Compare this to Canon, who have had two different lens systems even in the digital era. And though Nikon have preserved backwards-compatibility, it is sometimes at the expense of automatic features.

Incredibly, the situation is the reverse with Pentax. Not only do old lenses work on the K series digital bodies, they might actually gain extra features! Depending on the mount, you'll be able to automatically meter through the lens. And while manual focus lenses won't instantly become auto-focus, the focus indicator built into the body will tell you when you have got the focus right. Even better, you can use a simple technique called "trap focus" to ensure you never take an out of focus image. It's magic!

Why should this matter to you if you're starting out in photography in 2008? For one, it's nice to know that you're dealing with a company not set on orphaning your hardware investment. For another it opens up a huge range of used (and possibly inexpensive) gear on the secondary market. Plus it's just fun to have more options.

Besides the three primary advantages, Pentax cameras have numerous features that are comparable -- and sometimes better than -- those from other vendors. The body layout is ergonomic, especially on the K20D with its two thumb-wheels, allowing quick manual adjustments. Not only is there an anti-dust system, the camera will even tell you where the dust remains, to aid in cleaning. In an incredible innovation, stuck pixels in the sensor can heal themselves, thus saving expensive repairs or exchanges.

To be fair I should also give you a few reasons why not to choose Pentax. The primary one is that they are not as popular as Canon and Nikon. This means that it's more difficult to find a dealer that understands and stocks their range. It's more difficult to find other shooters to trade gear with. And it's almost impossible to find a store that will rent you lenses for one-off assignments. Popularity has its advantages.

The second reason applies only if you are absolutely in need of a full-frame camera. Pentax doesn't make one. To be fair even Nikon only introduced their full-frame model recently. This should tell you that very, very few photographers need full-frame images. The truth is that cropped sensors are already approaching (or have exceeded, depending on who you ask) the quality of the best 35mm film.

The third reason is a little less esoteric. If you want a full-on sports or action camera, Pentax might not be your first choice. Their frame rates are lower and the auto-focus system not as accurate at predicting movement. You can buy a better tool for this purpose, though it should be said you'll be spending significantly more money, since the entry-level models from competitors don't manage much better.

I'll look at some specifics of these bodies in the next instalment of this series, so you can decide which one to buy.

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11 comments:

L said...

While, for the most part, your column is well-reasoned, I have to take exception with the following: "To be fair even Nikon only introduced their full-frame model recently. This should tell you that very, very few photographers need full-frame images."

How do you arrive at this conclusion? Isn't the reason why many photographers have (until now) purchased cropped-sensor DSLRs, because that's what's been offered to them? I have several Minolta A-mount ultrawides, ranging from 14 to 28 mm, and would not buy a camera that would crop their FOV.

Oddly--and I believe that a number of other Maxxumites share my perspective--now that I know that Sony will make a full frame DSLR that will accept my A-mounts, I'm no longer in a hurry to acquire it. I will wait until the price drops at least into the mid-$2K range--like the Canon 5D--or until a Sony releases a less expensive version.

Right now, I don't have a digital camera at all, and am leaning toward acquiring a digicam (is that the correct description?) with the following features:
1) Outstanding zoom lens, with macro to at least 1:4.
2) Full manual focus and exposure control in macro mode.
3) Auxiliary flash capability.
4) Off-camera shutter release capability.
5) CF card acceptance.
6) Reasonable shutter speed and aperture ranges.
7) Reasonably compact.
8) Price well under cropped-sensor DSLRs from Sony.

Any recommendations?

One observation about in-camera anti-shake vs in-lens stabilization: I believe that some of Canon's IS lenses offer a second IS mode, that provides for great panning pics, with spot-on image registration. (Nikon's VR lenses may also have this feature, but I'm almost sure that AS/SS doesn't allow for this. This may not matter to most photographers.

robin said...

> Isn't the reason why many photographers have (until now)
> purchased cropped-sensor DSLRs, because that's what's been
> offered to them?

That is difficult to know, of course. I am not sure how many Canon EOS 5Ds (for example) have been sold relative to other cameras, and even if I did that might be more about the relative price of the cameras. Your point is a good one.

> I have several Minolta A-mount ultrawides,
> ranging from 14 to 28 mm, and would not buy a camera that
> would crop their FOV.

Fair enough. Cropped sensor cameras decrease wide-angle handling. But the popular Sigma 10-20mm zoom is a 15-30mm on a Pentax and a 16-32mm on a Canon, and this is enough for many. The advantages of getting extended reach in the telephoto range has greater appeal -- the 200mm lens from film days just became a 300mm. Gaining a quick 100mm in the long end easily compensates for losing 5mm in the extreme wide angle. (Again, for most people most of the time.)

My readings have convinced me that cropped sensor DSLRs have perfectly fine images that rival 35mm film, or even perhaps exceed it. If I needed more I would not be looking at full-frame so much as I would be considering a Hasselblad with a Phase One back. That is the next quantum leap in quality, and if I was a professional landscape photographer (for instance) I would be looking in that direction.

I have a good deal of respect for Nikon but very much expect their FF body was released due to market pressure and not because it made photographic sense. Many photographers think they want FF sensors just because that's the size it was back in film days. They forget that pros in the analog era often viewed 35mm as a horrible compromise compared with various medium and large formats. Strange that now some see it as the Holy Grail!

> Right now, I don't have a digital camera at all, and am
> leaning toward acquiring a digicam

A "digicam" generally means a digital video camera, and I am far from knowledgeable about those.

> One observation about in-camera anti-shake vs in-lens
> stabilization: I believe that some of Canon's IS
> lenses offer a second IS mode, that provides for
> great panning pics, with spot-on image registration.

This is great debate about the specifics of different IS implementations, and I do think that different Canon lenses, for example, implement IS differently and to varying degrees. The extreme price of the best of these is enough to dissuade research further, as is the fact that they are not even available in the types of lenses I need. More on this in a later article.

Thanks for the extensive comment. There is certainly lots to debate about in this areas and many valid points of view.

John Browne said...

Another advantage (other than getting an increased zoom range) using "full frame lenses" on Cropped sensor cameras is the reduction or elimination of fringeing and other distortions that occur at the edge of the lens.
If you look at some of the review websites you will find reviews of lenses that had only an average performance on film and full frame cameras but have now yield superb results on cropped sensor cameras.

The problem with pentax is the availability of their products in Ireland and even on the web. There are a huge range of lenses available at reasonable prices for Canon cameras and to a lesser extent Nikon Cameras. Personally I shoot with a cropped sensor Canon XTi (400D), I'm still getting used to it but it is a fantastic improvement over point and shoot cameras.

robin said...

> lenses that had only an average performance
> on film and full frame cameras but have now
> yield superb results on cropped sensor cameras.

That can certainly be true. The other advantage is that lenses made specifically for cropped sensors and newer bodies can be less expensive and more functional due to the omission of aperture rings, the use of quiet motor drives and the addition of features like quick focus. Lens technology is advancing along with body technology.

> The problem with pentax is the availability of
> their products in Ireland and even on the web.

No doubt.

> There are a huge range of lenses available at
> reasonable prices for Canon cameras and to a
> lesser extent Nikon Cameras.

But how many of them are image stabilised? Stay tuned for my lens article, which covers this perceived disparity.

L said...

"The advantages of getting extended reach in the telephoto range has greater appeal -- the 200mm lens from film days just became a 300mm. Gaining a quick 100mm in the long end easily compensates for losing 5mm in the extreme wide angle."

I always have to laugh when I see this assertion, as it is completely bogus. When you mount a full frame lens on a cropped-sensor body, you are truncating the FOV for that lens, regardless of whether it is a wideangle, normal, or a telephoto. You can achieve exactly the same result with that lens on a full frame camera body, by cropping during post processing, after you download your image. By doing it then, you control the amount of crop, rather than the camera sensor. Cropped-sensor devotees should really stop promulgating this canard about gaining reach by cropping the FOV.

L said...

"A "digicam" generally means a digital video camera, and I am far from knowledgeable about those."

Okay--should have said "point-and-shoot". Any recommendations for these, based on the eight parameters I listed?

John Browne said...

L,
I think Reasonably compact doesn't really fit in with the rest of your 7 requirements. Compact flash by the size of the card adds significant bulk as well as having the capability of mounting a flash unit.
Arguably the best "compact" digital camaera is the Canon G9. This however is far from cheap and is only marginally cheaper than an entry level SLR.
On your point about zooms and cropped sensors I would completely agree for a sensor with the same pixel density. However if you have 2 cameras with a 10 mega pixel sensor, one full frame and one cropped, you will achieve a higher quality image with the cropped sensor camera (after cropping the full frame to equivalent size) because the pixel density of the cropped senor is higher. This is of course assuming that the optical quality of the glass is up to it.

Robin,

Alot of people buy camea equipment based on availability, (I know i did), hence the popularity of Canon and Nikon.

I look froward to reading your lens article. There is an argument to be made that in camera optical stabilisation is not as good as in lens stabilisation, as the in lens versions actaully adjust individual lens elements to compensate for movement and can adjust for panning movements aswell as vibrations. I'm sure it's very annonying for your stabilisation system to blur an image because you happen to be paning a subject to take the picture.

robin said...

L wrote: "I always have to laugh when I see this assertion, as it is completely bogus. When you mount a full frame lens on a cropped-sensor body, you are truncating the FOV for that lens, regardless of whether it is a wideangle, normal, or a telephoto."

There is no such thing as a "full frame lens" in this context. Any lens of the same focal length will give the same FOV on a given sensor. With the 1.52 multiplier afforded by the APS-C sensor (Pentax and Nikon) a 50mm lens has approximately the same FOV as a 75mm lens on a 35mm film camera. You stated you do not want to lose the wide FOV on your 14mm lens. No doubt because you realise it will be acting as a narrower 21mm. How is this line of thinking "completely bogus" if you use it yourself?

L also wrote: "You can achieve exactly the same result with that lens on a full frame camera body, by cropping during post processing, after you download your image. By doing it then, you control the amount of crop, rather than the camera sensor."

While this is true you lose resolution doing this, obviously. No-one buys a significantly more expensive camera to throw away pixels. And I think you will find that serious photographers (yourself included I'm guessing) compose in camera, with what they can actually see. While minor cropping might be done later, it would hardly be common practice to say "I'll just vaguely shoot in that direction and crop out a good photo later".

robin said...

L: You asked for a point'n'shoot recommendation. I don't think I can make one based on the specs you are looking for, but the best camera bar none that I found after extensive research was the Fuji F10 (later improved with the F11, F30 and F31fd). At the time Fuji focused on performance and low light handling, creating a series of cameras that many regard as the pinnacle of p'n's. Subsequently Fuji joined the megapixel race and image quality took a dive. Check out The Online Photographer for an appreciation.

I actually have a surplus F30 I should sell or put on eBay -- since I cannot sell my partner's F10! We only need one p'n's between us. Having a camera of this quality sitting in a drawer is silly.

L said...

John and Robin - Thanks to both of you for your p/s recommendations.

My very limited understanding of digital photography is that (especially with p/s and cropped-sensor cameras) there is always a trade off between noise--particularly at higher ISOs--and definition, and that most photographers agree that 10 mp sensors on either is marketing overkill. There seems to be a consensus that camera makers should concentrate their efforts on noise and dynamic range, but because these are less understood by consumers, we're stuck with the higher mp derby. Since I am a complete ignoramus when it comes to digital photography, I'll defer to your expertise on this point. However, if I'm correct about the above, wouldn't that marginalize the argument suggesting higher IQ from higher-density photosites on cropped-sensor DSLRs over those found on ff DSLRs? BTW, the "full frame" lens reference is commonly accepted to mean "full 35 mm format". The only people who ever get "confused" by this are cropped-sensor DSLR and Oly 4/3 fans LOL.

Robin - I may be interested in buying your Fuji, but I don't want to further divert your blog by discussing this here, so I wiil send you an email in the next couple of days on this.

robin said...

"However, if I'm correct about the above, wouldn't that marginalize the argument suggesting higher IQ from higher-density photosites on cropped-sensor DSLRs over those found on ff DSLRs?"

The APS-C ("cropped") sensor is ten times larger than a point'n'shoot sensor. A full frame sensor is somewhat over two times larger than an APS-C sensor. So, yes, it has more information and can resolve finer detail. But the degree of improvement is significantly less, and so is difficult to justify on a cost basis. This is because the cost of making a sensor rises rapidly (it's a Poisson equation) with sensor area.

If I was writing about the best technology regardless of price, my recommendations would be different. Instead I am trying to ascertain the point on the price curve where one gets the best bang for the buck. Then it's just down to taking good photos!

"BTW, the "full frame" lens reference is commonly accepted to mean "full 35 mm format". The only people who ever get "confused" by this are cropped-sensor DSLR and Oly 4/3 fans LOL."

I have never known anyone to get confused by this as it is obviously correct. :-) In the statement you are referring to I was only meaning that "full frame" lens or not doesn't matter for FOV calculations. It only matters in terms of the size of the image cast at the sensor. And that is different from the field of view the lens is covering.

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