Readers Weigh In on the Olympus 25mm ƒ/1.2 (and the Pentax HD FA 50mm f/1.4 SDM AW)

One reader said the M.Zuiko ED 25mm ƒ/1.2 PRO is the equivalent of an ƒ/2.4 lens. No, it isn't. It's an ƒ/1.2 lens. F-number is the ratio of the system's focal length to the diameter of the entrance pupil. It's a quantitative measure of lens "speed," i.e., the amount of light that passes through the lens. There is no such thing as f-number "equivalency" (and Earth is not flat, and I don't care what the Internet says to the contrary about either of these issues).

Other readers said it is really a wide-angle lens. Nope again, because angle-of-view descriptor words take into account the format of the lens-sensor system for which the lens was designed. A 300mm plasmat used on an 8x10-inch view camera is not a super-tele or "long" lens just because it's 300mm in focal length. Like the 25mm Olympus, it too is a normal lens.

Moving on....

Pinnacle
Two readers (inadvertently) pointed out my deficiency as a blogger by mentioning the upcoming 15-element Pentax 50mm ƒ/1.4, which I have yet to write about (sorry).

Robbie Corrigan said: "I wonder if this all kicked off with the misunderstood Pentax DA*55mm ƒ/1.4 for APS-C...more correction, more glass. [Here are my thoughts on that one —MJ.] There is another behemoth in the 50mm class, the HD FA 50mm ƒ/1.4 with 15 elements in nine groups. Luckily Pentax have stated that they are not going for chart-test success but are chasing superior rendering. Saying that, while its rendering is gorgeous, with delicious transitions to out-of-focus and beautiful bokeh (to my taste at least—bokeh is a personal thing), resolution-wise it is no slouch. Here are the specs and here is the development story."

Pentax Big Rig: FF, 36 MP, SotA lens. Shhh, nobody mention the size,
weight, and cost compared to an LX with an SMC Pentax-M 50mm ƒ/1.4....

Thanks for the links Robbie. It's kind of amusing that on the "Development Story" page, they never give the names or positions of the interviewees. That's so Japanese...they just consider it impolite to make stars of individuals. The speakers are identified only by their last names and with the group rubric "section leaders." Well, at least there are (unidentified!) pictures of them.

We ought to be grateful for the unapologetic mission statement, which, with its superlatives, is also somewhat uncharacteristic of the modesty of the Japanese: the person identified as Iwasaki states, "We did our very best, so [the lens] provides the highest optical performance to be found in a single-focus standard lens. ...We can't tolerate even a single specification that is inferior to those of competitive products." He says it's "a lens we consider the pinnacle of Pentax lenses."

John Krumm has actually been using one (the new Pentax, not the Olympus, which we'll get to), and he's posted a gallery of samples. "I've been enjoying Pentax's brand new über-50mm for the last week," he writes. "Alas, it only has 15 elements, but it makes up for it in sheer bulk. It's truly a massive 50mm ƒ/1.4. But I totally love it. Strange how things work out. Here's my gallery of assorted first day images."

You'd think I'd have written about this lens, given that, at one point or another in my hobbyist career, I owned every single fast Pentax 50mm, all the way back to the M42 screwmount Super-Takumar of 1964. The HD FA is the latest in a long line I was once very familiar with.

Speaking of pinnacles, our friend Geoff Wittig is susceptible, but likes Sigmas: "I will confess to having a serious weakness for such spectacular über-lenses. I own a set of Sigma's beautiful 'Art' lenses, and they are optically wonderful. The 35mm ƒ/1.4 is probably the sweet spot, both crazy sharp and reasonably compact. The 85mm ƒ/1.4 is fabulous if...large...but the 135mm ƒ/1.8 is my favorite. Huge but still quite manageable, and my favorite portrait focal length.

"I just broke down and bought their new completely over-the-top 105mm ƒ/1.4, and I'd have to say Sigma have jumped the shark with this one. Seventeen elements in 12 groups, and weighing in at a completely bonkers 3.62 lbs. (1.64 kg). Yes, it's crazy sharp with very little vignetting, and focus is surprisingly fast for the massive amount of glass moving around. But it's ludicrously ginormous, with a 105mm diameter front element. It has a tripod collar...and it really needs it; this beast is too heavy to handhold for more than 15 minutes at a time. On the bright side, Sigma cleverly machined an Arca-Swiss compatible dovetail into the tripod foot, so you don't have to buy a custom plate from Kirk or Really Right Stuff."

The star of the show*

At last wending our way to our putative subject, here are three comments from owners/users of the Olympus 25mm PRO:

Zed Martinez writes: "I bought one to fill the 50mm-e slot in my line (originally the 17mm ƒ/1.8 and 45mm ƒ/1.8 for routine use, and the 75mm ƒ/1.8 for headshot work). I was intrigued at how over-designed it was, and I needed a good weather-sealed lens for the E-M1 Mark II and wasn't feeling the zooms (I like the DOF control better on the primes). In my (much more limited than most commenting on here) experience, it's a solid lens.

"Flare is oddly minimal for the number of elements, and hard to invoke, though when you manage it it's a bit uninteresting aesthetically to my taste. Mostly some small ghosts and only with the hood off and trying on purpose did I bring in some veiling flare.

"The bokeh is stellar, and it's very difficult to get even a hint of nervousness or busy-ness from it. The usual 'but it's like an ƒ/2.3' in full frame terms don't quite cut it for me here because I don't know how many times I've opened a file that looked like it was in perfect focus to notice that the DOF was still narrower than expected and that I had missed the target. I'll take that extra depth wide open, thank you, so long as the bokeh stays that smooth. Tonal transitions are very smooth as well, though the contrast seems dialed down a bit with them versus the ƒ/1.8 lenses. I'd say the real disappointment of it, if any, is that those 19 elements sorta kill the actual transmission, so, an ƒ/1.2 it may be but it only pulls shutter speeds like an ƒ/1.4 most of the time.

"It's an interesting and hard-to-qualify lens. Every time I use it I think maybe in the quest to make it perfect Olympus lost some of the character the ƒ/1.8 primes have, and I always think to myself despite what I paid for the 25mm ƒ/1.2 I prefer the other two primes for their 'look.' And then I check Lightroom and I have as many photos I've kept from the 25mm ƒ/1.2 as from the other two smaller primes combined. Despite not preferring the 50mm-e view. I guess when it's good, it's very good, and what it does, it does well. I don't regret the money spent on it, anyway, but I can see how it's a hard sell against the 12–40mm these days when, for that money, more people would want the zoom."

Thanks Zed.

Peter Wright writes: "I have had the Olympus 25mm ƒ/1.2 PRO for just over a year now. It came out at the same time as the 12–100mm ƒ/4 PRO which has to be much more practical, and was/is much more popular. But me? I had to have the 19-element 25mm! (It's a weakness, but the weakness, as they say, is so strong!) It was as if some lens designer at Olympus had been simply told to pull out all the stops and make the best lens possible. I think they succeeded wonderfully!

"I'm fortunate to also own the Leica Summilux 50mm ƒ/1.4 which I have now had for about four years and use on my digital Leicas. It also is a lens for the ages. Sometimes, when I look at my prints I can't tell whether I used the Olympus or Leica on their respective cameras, as they each have a similar character, and I need to consult the metadata to find out.

"Interestingly, the Summilux is much smaller than the Olympus, in spite of having to cover a sensor that is four times the area that the Olympus needs to deal with. Of course the Summilux doesn't have autofocus, but I don't think that that accounts for the size difference. The Summilux is also about four times the price of the Olympus. These are two very different lenses that each achieve excellence in totally different ways.

"Is it rational to own lenses like these? No. Does it make me a better photographer? No. Does it make me a happier photographer? You betcha!"

We'll give Steve Biro the last word (although there are other good comments in the Comments section of yesterday's post): "I’m not that big (pun intended) on über primes, generally preferring smaller, lighter ƒ/1.8 and ƒ/2 glass. But, for some reason, I am now the owner of this 25mm ƒ/1.2 piece from Olympus. What I can tell you is that this lens delivers fabulous quality even when used wide open. And I can get that quality even when using it in poor light without a flash. ‘Nuff said."

(Actually, there's never enough said about camera lenses. What are we going to talk about when the only lenses anyone uses are in smartphone modules?)

The whole rig counts
Finally, Ken Tanaka, being perhaps too reasonable, writes: "In my experience and opinion Micro 4/3 sensors simply aren’t good enough to reward such a high financial and technical optical investment. They’re 'good' sensors but haven’t really made much advancement since their introduction. Packaging (camera body styling) has been what this line is really all about. I enjoy my GX9 but it ain’t gonna be wearin' no 19-element lenses!" [I edited this because of what I thought were typos.... —MJ.]

Hate to say it but I kinda agree with Ken here. If you want to, of course, you should get the Olympus lens. Zed, Peter and Steve seem to like it, and there's nothing wrong with having the best toys (or, if there is, I'm certainly not the guy to talk you out of it). But if I were after the pinnacle of many-element lens performance I do think it would make more sense to get at least a full-frame camera of 24 MP or more—with "more" probably being more justifiable. Those Sigma ART lenses on Geoff's Canon 5DS or the HD FA 50mm on a K-1 Mark II, or Leica's 50mm Summilux-SL on an SL would make an over-the-top lens exercise more sensible. I'd go that route rather than getting the Olympus lens.

...But I'm still really GASsed out supine and stupid by the Olympus lens. I'll get over it.

I'll tell you what I do wish, though...I wish Panasonic would fix the focus on my 20mm ƒ/1.7. Optically it's still one of my favorite lenses, but it's remarkably slow to focus, and the more time goes by the more I'm annoyed by it. That's a different post, however. And this one's long enough.

Have a good one
As usual I'm taking tomorrow (Saturday) off, and I'll have a nice announcement for Sunday to make up for last Sunday's depressed post.

Thanks to everyone for their comments. Hope you have a nice weekend.

Mike
(Thanks to everyone)

*I'm easily distra...hey look, a rabbit!

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(To see all the comments, click on the "Comments" link below.)
Featured Comments from:

Huw Morgan: "Hi Mike, Isn't a 25mm ƒ/1.2 lens on Micro 4/3rds equivalent to an ƒ/2.4 lens on full-frame if you are talking about depth-of-field?"

Mike replies: Sort of, but not really. First of all, d-o-f is a secondary effect or characteristic of aperture choice, not the primary thing being specified (the primary thing being specified is the diameter of the aperture opening relative to the optical system's focal length); so if one means "depth-of-field equivalency wide open," then it behooves the speaker or writer to specify so, each and every time he makes the claim, rather than just blithely stating that 2 = 4 or whatever and expecting people to nod in agreement.

Second (and this is not well understood out there on the wilds of the Internet), depth-of-field is not a stable or measurable characteristic of a photograph. Optically it depends on the "acceptable circle of confusion," which is first of all a matter of taste and judgement...it means how much blur you'll accept before you consider it noticeable or objectionable. Some people are more sensitive to it than others. Other people simply have different standards.

Next, blur depends on a number of factors not related to aperture choice: the resolution of the film or sensor (more resolution, less acceptable circle of confusion); the degree of enlargement, whether on screen on in a print; and the other optical characteristics of the lens contributed by the glass elements and the lens design.

Let me see if I can explain each of these things by using somewhat extreme cases. For the first, let's return momentarily to film. Imagine that you have an extremely high-resolution, fine-grained film, and a low-resolution, coarse-grained film. Now you take two identical pictures with the same equipment using the same lens aperture and with the plane of focus in the exact same place. Let's call the plane of focus "0" and then imagine several more planes in back of it, progressively farther out of the plane of focus, which we'll label 1, 2, 3 and 4. With the fine grained film, you might be able to resolve 0 and 1 with the same level of apparent sharpness. The system resolution allows you to see that 3 and 4 actually show some blur. With the coarse-grained film, however, the resolution of plane 0 is not high. In fact, it's no better than it is for plane 4. So, in that image, sharpness or resolution will be the same for 0, 1, 2, 3, and 4, because it's limited not by the position of focus and the acceptable circle of confusion but by the resolution of the film. But the visual effect is of greater depth-of-field for the picture taken with the coarse-grained film; even the image objects at 4 look just as sharp as the image objects at 0.

You can demonstrate the same effect by using a Photoshop filter. If the filter coarsens the system resolution, it will bring more of the image front-to-back into "best sharpness" for that image, making it look as if depth-of-field is different with and without the filter.

A similar thing happens with degree of enlargement. I'll make a visual demonstration. Look carefully at this digital image I took a number of years ago of my friend Jim and his daughter: 

At this 400x600 pixel enlargement size, it's difficult to tell where the plane of focus is and whether both people are in focus (although I bet some of you are guessing correctly). But take a look at 100%:

...Not subtle at all. This is an extreme example, but generally the more you enlarge, the more the differences in d-o-f are emphasized. Small enlargements make it look like there's more d-o-f and large enlargements make it look like there's less. As a printmaker, I often told clients that "the negative won't stand enlargement past 8x10" or whatever, and in some cases what I was doing was simply making my own judgement call as to when the d-o-f insufficiencies began to call too much attention to themselves. (And of course we have further tricks to hide such discrepancies, whether under the enlarger or in Photoshop.) Even viewing distance from a print has an effect.

Finally, the lens itself—its design and its aberrations—has an impact on apparent sharpness and hence on apparent d-o-f. What if one lens has extreme curvature of field and the other doesn't? The apparent d-o-f may be different. What if one lens has highly corrected spherical aberration and the other has undercorrected spherical aberration? The apparent d-o-f may be different. What if one lens is very sharp in the center and very soft in the corners and the other has lower center sharpness but is more even across the field? The apparent d-o-f may be different. What if one lens is soft wide open and the other isn't? The apparent d-o-f may be different. And so on, and so on.

And one lens might simply have jarring, jangly bokeh that's hard to look at while the other one has smooth, dreamy bokeh that's a pleasure to look at, such that most viewers can take a lot more of the one than the other. Of course, larger formats make it easier to achieve less d-o-f if that's needed. Another way of saying that is that adequate d-o-f is harder to achieve with overly large formats. I'll repeat, though: depth-of-field in pictorial photography is a matter of creative judgement and not a property that is measurably stable across all lenses, such that one can meaningfully say "this is equivalent to that."

Finally, there are just lots and lots of ways to manipulate d-o-f when you're shooting, most recently purely in software by using the "Portrait" setting on an iPhone. The format you choose certainly has an influence on the look of your pictures vis-a-vis the look you're after, and I'd never dispute that. We're always splitting differences, and adroit practitioners will alight where they're most comfortable.

So when you say "ƒ/1.2 on Micro 4/3 is equivalent to ƒ/2.4 on FF," what you really mean is that ƒ/1.2 on Micro 4/3 has roughly similar apparent d-o-f wide open to a picture taken at ƒ/2.4 on FF, if the camera position and setup are the same, the lens's angle-of-view is the same, the lens designs are the same, the system resolution is the same, the degree of enlargement is the same, and the viewer's aesthetic standards for acceptable blur are the same...and by the way we're glossing over the little fact that the ƒ/1.2 lens lets about two more stops of light past its aperture opening.

Achievable narrow d-o-f (seldom a virtue until lately, and, I might add, often overdone lately) has always been variable between formats, but never in history until about the 2000-aughts did anyone in photography ever use the locution that one f-number is equivalent to—the same as—another, while not even mentioning the fact that the lens speed of the two is not remotely the same even though the f-number number was primarily devised to signify lens speed in the first place. I don't know, are people talking about Fuji GF lenses in terms of their open-aperture d-o-f equivalents to FF? Fuji would probably like it if they would, because it would make all its GF lenses magically faster. And what's the FF "equivalent" d-o-f blur of a 300mm ƒ/5.6 plasmat on 8x10 wide open?

From a wordsmithing standpoint, I'll say as a former editor that it's simply not correct to write "ƒ/1.2 on Micro 4/3 is equivalent to ƒ/2.4 on FF." It's wrong on its face. We should write, "With an ƒ/1.2 lens on Micro 4/3, d-o-f blur wide open might be expected to be roughly similar to d-o-f blur at ƒ/2.4 on FF, all else being equal...."

Of course, as Ctein was wont to say, all else is never equal....

The above will have H—>0 effect on this issue generally. And this was supposed to be my day off, dang it! No rest for the cranky!

Jim Richardson: "I have yet to understand why lens equivalent fanatics feel obsessed with comparing the 'effective' f-stop of Micro 4/3 lenses versus their full frame counterpart, but do not feel the need to compare the effective f-stops of full frame lenses to medium format lenses. The same rules should apply, making the medium format lens have an ever faster equivalent f-stop. Yes?"

Mike replies: Made me smile...your comment was the very first one I read after posting the above lengthy reply to Huw in which I asked the very same question. I really do want to know what the effective-equivalent people would calculate the FF-equivalent f-stop of the Fujifilm GF 110mm ƒ/2 to be. By their lights, that's one hell of a fast lens.

[Jim is a National Geographic photographer, BTW. Here's his website, which has lots new since I last visited.]

Jim R. replies to Mike: "I feel it is my duty to support anyone who is willing to get up on the soapbox about depth-of-field. We gotta stick together. (Oh, and thanks for mentioning my website. I never keep up as much as I should but, well, there it is.)

And while we are ranting about depth of field let me offer this. I often teach students that one of the simplest ways to decrease the apparent depth-of-field (i.e. render the background blurry) is to kneel down. If you are photographing another person while standing up much of the frame area will only be a few feet behind the subject. If you kneel down much of the background picture area will now be out at the horizon, effectively at infinity. Voila! Less depth of field. I'm convinced this is also why pictures taken with twin lens reflex cameras had such blurry backgrounds: they were being shot from lower angles. (At least it worked that way for me using my dad's Zeiss Ikoflex when I was a boy photographer on the farm.)

Mike replies to Jim R.: Well, of course, and it's probably why this nonsense frustrates me. Because comparing d-o-f for like-to-like shots with different equipment is just not how photographers see, or work, or conceptualize. We learn our equipment, and then we get the d-o-f we want, and if we're not getting what we want, we change something about the setup—use a longer lens or put the in-focus objects closer to the lens or whatever. It's not like there's one and only one picture in front of your eyes. Then if we're not within our own comfort range often enough, we change equipment. But for heaven's sake, there's no sense in redesigning the wheel and confusing people saying that ƒ/4 is equivalent to ƒ/8 when it's nothing of the sort...just say you'll have a generally easier time getting less d-o-f with larger sensors or film if it's what you want, and leave it at that.

Jim Bullard: "I'm totally with you on ƒ/1.2 is ƒ/1.2. There is a group of photographers (mainly videographers I gather) who compare the light coming out of the back end of various lenses and then rate them with what they call 'T' stops or actual light transmission because there is light loss internally on some lenses so they claim those lenses are inaccurately labeled. It demonstrates a misunderstanding of how the f-stop rating is derived. It is just math, a simple ratio of aperture diameter at maximum aperture divided into the focal length when the lens is focused on infinity. A 1-inch opening on a 2-inch lens is an ƒ/2 lens. The actual light transmitted changes as you focus on anything closer, cutting it by up to 75% when the same lens is focused at 1:1 due to the law of inverse squares."

Two different guys [comments paraphrased and summarized]: "Mike, you ignorant slut." [Note however the oblate ellipsoid image of the Earth rotating at the end of this antediluvian SNL clip. Did they know nothing way back then?! —Ed.]

Andy Munro: "Re your comments on the focus speed of the Panasonic 20mm ƒ/1.7. I have to agree. I owned one a long time ago and recently bought a copy of the updated version. I bought it as I wanted a pancake lens around 35–40mm-e and I liked the original but the focus speed is annoying me more this time around."

Mike replies: I think it's because we continually re-establish our expectations. I was never bothered by the focus speed of the 20mm on the old GF1. But on the GX8 it's so much slower than the focusing of the 12–35mm that it bugs me.

John Krumm: "Sure, feature me and then let it turn into an equivalency thread.  :-)  For those interested in my first day thoughts on the new Pentax 50mm, I have the same images on Pentaxforums, with commentary...I also have a post with a wide open snap-portrait of my daughter...where you can see it fails your 'soft' requirement. But of course the rest of her face is slightly out of focus so that does indeed soften...."

Mike replies: Maybe that new Pentax 50mm will be the new King of Bokeh? Lovely.

Comments

[Craig]

I'm really tired about the so-called "equivalencies" between full-frame and other formats, especially when people misunderstand them and think that a 35mm APS-C lens is "really" 52mm. No, it isn't! When you get right down to it, every format has its own characteristics. The "equivalencies" are just ways of trying to draw correspondences between them, but these correspondences are always imperfect.

Re the Pentax 50mm lens, I find it kind of interesting that they're now creating insanely huge, heavy, complex normal lenses. Back in the day, manual-focus Takumars always seemed smaller and lighter than comparable lenses from Nikon, Canon, or Minolta.

[Isaac]

Of course 1.2 is 1.2, but 25mm is also 25mm and not 50. If you convert, convert everything.

You might also believe that, having the same depth, a bucket with a diameter of 1 foot collects the same amount of water than one with a diameter of 2. No, it wont, it simply wont. The latter will collect 4 times more water. It's basic physics.

Lenses wok the same and a FF 50mm ƒ/1.2 will collect 4 times the light/photons per unit of time than a M43 25mm ƒ/1.2 because it has 4 times the collecting area.

But like I said in that other comment, I don't care. M43 works more than well enough for me with its pros and cons.

[Eolake]

I think your reader meant that the depth of field of the 25mm 1.2 is equivalent to a 50mm 2.4.
(I’m not getting mixed up in that, there is so much confusion about that. A video I saw from a big site had in the headline that smaller sensors have less depth of field...)

[Moose]

I love the juxtaposition.

". . . my 20mm ƒ/1.7. Optically it's still one of my favorite lenses, but it's remarkably slow to focus

20 mm, F1.7, 6/7, 55.5x20.5 mm, 55 g.

"...But I'm still really GASsed out supine and stupid by the Olympus lens."

25 mm, f1.2, 19/14, 70x87 mm, 410 g.

[Ernie Van Veen]

"What are we going to talk about when the only lenses anyone uses are in smartphone modules?" - Stop scaring me!

[c.d.embrey]

Isn't f/2.8 equivalent to 17 miles an imperial gallon 8-)

[Ross Attix]

From Mike’s post, “Other readers said it is really a wide-angle lens. Nope again, because angle-of-view descriptor words take into account the format of the lens-sensor system for which the lens was designed.“

Yup. And to figure what is a “normal” lens for any format, you go by the diagonal measure. In film cameras 35mm format was about 43mm. 6x6 was approximately 85mm, and using Mike’s example of an 8x10 view camera, a 300mm (or 12”) was normal. Optics are optics and that stuff is all the same no matter what type camera you are talking about.

[HR]

I agree with Ken Tanaka about not buying very expensive m4/3 lenses. I have used m4/3 for 6.5 years and am still quite happy with it for my purposes. Currently I am using the PEN-F and E-M10II. The Olympus f1.8 and Panasonic f1.7 primes are small, not overly expensive, and very good. That is what I want. I don't want the big, very expensive lenses. If I did want something them I would instead just go ahead and get a FF body (Sony mirrorless, maybe a future Canon/Nikon mirrorless, or DSLR) and get some good primes to go with it.

[HR]

With regards to your comment on the AF speed of the Panasonic 20mm f1.7, while it is a bit slower than my other 10 or so m4/3 lenses I found while spending time on multiple occasions playing with the Fuji X-Pro2 and X-T2 with the Fuji 23mm f2, Fuji Zeiss Touit 32mm f1.8, Fuji 35mm f1.4, Fuji 35mm f2, Fuji 56mm f1.2 that the 20mm f1.7 on my E-M10II at the same time/place could S-AF as fast as those lenses. I haven't heard much complaining about the S-AF speed of those Fuji primes.

[David Dyer-Bennet]

If your life is about depth of field then apertures are equivalent by one rule; if you care primarily about exposure, they're equivalent by a different rule. (And it's often a matter of what your kind of photography gives in abundance vs. what is always in short supply, as much as differing preferences.)

For me, DoF is nearly always something I'm struggling to get more of under dark conditions, and exposure is the real limitation on getting the picture at all, so I care about the f/stop as stated (okay, okay, what I actually care about is the t/stop).

Similarly, when I was growing up, tilt lenses (and tilts on view cameras) were primarily used to give the appearance of much more depth of field than was actually present, to make the pictures people wanted (not just art/landscapes, but product photography). Now, people buy them mostly to "misuse" them to reduce the apparent depth of field.

Certainly limiting DoF to reduce background distractions and help focus attention can be a very useful technique; but it's still the exception in my work.

[Slobodan Blagojevic]

Isn't if fair to say that DOF of an f/1.2 lens in m43 is equivalent to DOF of an f/2.4 lens in 35mm format?

[Oskar Ojala]

I dislike the oversized 50 mm lenses. Part of the charm of the fifty is that it can be put on the camera and casually carried around, taking pictures with a setup that's pretty compact and evokes the feeling of SLRs from the 70s while delivering high image quality. But look at that Pentax! I first thought it was a 645 format camera; full frame DSLRs are the new medium format in terms of size.

Since I very much like the 50 and put my money where my mouth is, my carry-anywhere 50 is the Sony 55/1.8, which is very light, focuses fast and renders a pleasant image at any aperture. Granted, it's only f1.8 (on full frame, equivalent to f1.8 as can be read on the Internet), but in this day and age I rarely feel the need for f1.4 since ISO 800 is still fantastic and modern lenses are sharp even at the largest aperture. For more meticulous use, I choose the Voigtländer 65/2, which is bigger, a macro, not 50, has "only" 10 elements and is at the top of the game in terms of performance.

[JH]

Perhaps this illustrates why you should be writing technical books on photography rather than thrillers. Have you thought about a "best of" book from the blog?