So what's wrong with these statements:
"I bought a car that will go 140. So I'm darn well going to drive 140—I certainly didn't pay for car with a top speed of 140 to drive it at 80!"
"My winter coat is rated to –30°F. So I don't see the point of wearing it unless it's at least –25° outside. Why would I pay for a winter coat that keeps you warm at –30° and then wear it when it's only +10°?
It seems to me I hear comments about photo equipment that are similar to these with increasing frequency these days.
Of course it's up to each individual how they feel, and I don't mean to criticize.
One comment I've encountered is that Micro 4/3 cameras are supposed to be small, so they can't see the point of, say, the Panasonic GH4, because it's large. I get criticized sometimes because the NEX-6 I use is small but the normal lens I use for it, the Zeiss 24mm, is too large. What's the point of having a small camera if you have to use big lenses?
Seems pretty handy to me though. I once owned a Nikon F4!
Why would you buy a Fuji 50–140mm ƒ/2.8 zoom, when it's large? Isn't mirrorless supposed to be small?
Another common one is when people think they have to shoot an ƒ/1.4 lens at ƒ/1.4...otherwise, why did they pay extra for the big maximum aperture? So they shoot at ƒ/1.4 every time—even when it's obviously not enough depth of field.
I just seem to encounter this attitude a lot, is all. "I paid for feature X, and I'm damn well going to use feature X—every single chance I get."
This shot is just here as decor. It means nothing. Just foolin' around.
I don't think the basic attitude there is a very sensible one. You pay for features so they're there when you might need them, is all. And sometimes, you sacrifice certain features to get other features you need more.
That one about having to shoot a fast lens wide open every time is the one that best highlights the discrepancy for me. I spent the first half of my life avoiding large apertures, because most lenses perform at their worst wide open. And nowadays, I see lots and lots (and lots) of pictures that are taken with what I think are inappropriately wide apertures—pictures in which the photographer has reflexively tried to maximize the amount of blur, but just doesn't have everything in focus that (in my judgment) ought to be.
A large Micro 4/3 camera isn't necessarily a non sequitur...just because it's got "micro" in the name doesn't mean everything associated with it must be tiny. Maybe another camera you have can be tiny. And it's all right to have a large lens for a mirrorless camera—don't worry, maybe some of your other lenses can take advantage of the compactness of the mirrorless concept. You can own an ƒ/1.2 lens even if you don't use it at ƒ/1.2 very often. Hey, the big stop is there if and when you need it. And maybe you really will need it now and then. Just having it there for peace of mind might be enough to justify the extra cost for some owners.
Two photographers are walking in Central Park. A flying saucer lands and Elvis comes down the ramp riding a unicorn. The first photographer says, "And I don't have a camera with me! Where's that pocketable digicam you bought?" Second photographer says, "I paid for a pocketable camera, and damn it, it's staying in my pocket!"
Don't take this personally. You're entitled to use your own equipment however you like.
As I sometimes say, though, I'm just sayin'.
Mike
Original contents copyright 2014 by Michael C. Johnston and/or the bylined author. All Rights Reserved. Links in this post may be to our affiliates; sales through affiliate links may benefit this site.
Shore these possessions against thy ruin
(To see all the comments, click on the "Comments" link below.)
Featured Comments from:
Patrick Perez: "In defense of a fast lens is another reason separate from ever shooting wide-open: the fact it will help the autofocus in lower light levels, even when shooting stopped-down. That is why I generally prefer a lens around ƒ/2 to ƒ/2.8, even though I don't shoot wide open very often."
Gordon Lewis: "This reminds me of a friend of mine who kept his DSLR sent to ISO 1600 because he had read somewhere that the advantage of DSLRs was that they produced better results at high ISOs."
Mark Walker [he doesn't say so, but I believe Mark works in a camera store —Ed.]: "I'm going to rant. I wholly concur. I think this has been an increasing phenomenon, as if there's some point to prove. Lots of (wanabee) 'photographers' have no idea of the way lenses perform and what different ones can do. As we have more, easier access to information the less it is rationally processed in my view. Absurd claims and falsification are a veil over the Internet that nourishes expectation and opinion.
"Facing customers who are disappointed with their latest fast lens because they think it isn't 'perfect' is a testament to the rife absurdity that manifests with increasing frequency. Our turnover of secondhand hardly used high quality lenses astonishes me. It's every aspect that 'equipment man' (mainly men I think) will pick up on. A common one is using a camera in continuous shooting mode all the time—do they drive cars on the red limit when they run to the shops—and preferably at 1/8000th?
"Don't get me started on the new Fuji telephoto: 'it's too heavy'; what? You think Fuji decided to do make it too heavy for you? Bah! It does my head in. Could we get an Internet movement going extolling the virtues, indeed necessity, of shooting at, say ƒ/5.6 ? Could a poll be taken of our favourite apertures or shutter speeds ? I think some people would seriously answer that."
BH: "I'm guilty of the wide aperture thing, and it drives me nuts. Whenever I get a new, fast lens I end up shooting it wide open for every shot for a month before I get over it. This makes just about zero sense for my style of photography, so I get approximately zero worthwhile shots during this period. Eventually I get to ƒ/4 or ƒ/5.6 and all is right in the world again."
marcin wuu (partial comment): "There's no such thing as 'too wide' when it comes to aperture. This might come from a different understanding of the term 'performance' when it comes to the lens parameters. For me, lens performance judgement is based on what I can I do with the depth of field when using said lens. Sharpness, contrast, aberrations, diffractions—it's all fluff to me. Irrelevant.
"So, I paid extra premium to get the feature set I need, and I see no discrepancy using this feature all the time—precisely because that's what I got it for. People scoff at shallow d-o-f, which I also don't get (because I love shallow depth of field obviously), but what I get very well is, people will scoff at anything."
I think you're misreading a lot of these (genuinely annoying) comments. They're mostly not addressed to people who have already acquired these products telling them how to use them. They're mostly addressed to either one of two audiences:
1. People considering purchases, who are being urged to reflect on their actual needs.
2. Manufacturers, who are being scolded for not meeting the needs of the person complaining.
The point of "What's the point of buying an f/1.4 lens if you're not going to use it at f/1.4?" isn't that if you have that lens you have to always use it at f/1.4 -- it's that before shelling out the extra money for that feature, you should stop and ask yourself why it's a feature that you expect to really benefit from enough to justify the cost. Different people will have different standards of "enough", but, given the often unhealthy draw of shiny features and impressive-sounding specs, it's not a bad thing to remind people to at least ask themselves the question.
For "I thought mirrorless was supposed to be small!" we have something that usually seems more manufacturer-directed. Suppose (hypothetically) I'm a would-be mirrorless buyer, and that my reasons for being interested in mirrorless cameras are mostly size savings. Suppose further that the Sony E-mount APSC system seems generally appealing to me, and that my shooting preferences lean towards prime lenses, and my preferred field-of-view is in the vicinity of 35mm-equivalent. Well, I look at the Sony lens lineup, and I see that the only prime for me is pretty honkin' big, relative to the camera. Yeah, sure, we're still not talking a pro-SLR-sized kit, but the size of the lens is undoing a lot of the benefit that made this system appealing to me. It's not like I object to big premium lenses being there, but I feel like the size-conscious buyer is part of the core mirrorless market, and I feel like in this capacity I'm being underserved. So I'm bitter at Sony for rolling out this huge premium lens instead of something smaller and cheaper that would meet my needs and what I perceive to be the needs of a lot of other mirrorless buyers, and then I express this by saying "I though the point of mirrorless was to be small!" This is not such a deeply unreasonable kind of frustration, although the usual forces of internet drama can of course transform it into something pretty ridiculous.
Posted by: B. R. George | Sunday, 07 December 2014 at 02:41 PM
...pictures in which the photographer has reflexively tried to maximize the amount of blur,...
This really strikes a nerve with me. I see a lot of discussion (mostly among tech nerds) where the only important thing about a lens is how much blur they can get. Now I don't object to good bokeh, but give me a break! If all you care about is interesting blur, try a pinhole or a Holga.
Bill
Posted by: Bill Tyler | Sunday, 07 December 2014 at 03:26 PM
MJ,
Yup, this column really hits it on the head. Some folks have the same philosophy about driving (it seems to me) I'v got auto insurance so I'm gonna use it....craaash.
And...seems to me the M4/3 format should not have the "micro" name. Who says its gotta be "micro" size cameras/lenses. In any case my em1 and 12-40 is tiny compared to the dslr and similar lens I'v got. My shoulder sure knows the difference. On screen the difference is "micro"!
jb
Posted by: JB | Sunday, 07 December 2014 at 03:32 PM
If all photographers only bought gear with they really need, they could save a lot of money - and camera manufacturers would go bankrupt.
Also, there is nothing worse ergonomically than a lens that is too heavy in comparison to the camera body. This is why all these "Frankenstein- rigs" exist for video shooting, and all of them are still a huge pain.
Posted by: Bernd Reinhardt | Sunday, 07 December 2014 at 03:33 PM
The other issue with those types of arguments is that, presumably, folks are saying you might as well go with a larger sensor if you're going to be using a large camera or lens anyway. Of course, going with a larger sensor system, which will generally mean an even larger (and more expensive) camera or lens...
Posted by: V. Roma | Sunday, 07 December 2014 at 04:00 PM
Essential to creativity is experimenting and failing. If you have the tools to be creative, but are too insecure to fail, how are you ever going to know what works?
Posted by: Darlene | Sunday, 07 December 2014 at 04:14 PM
I don't get it either. Maybe with the camera gear it's a sort of way to justify a high-dollar purchase, and maybe brag about the price: "I paid a ton of money for this lens, but look at this shallow DOF." Very often this comes from people who seem more interested in the gear than in the pictures. The real photographers play with the wide aperture "till the new wears off" (and they understand the lens) then go back to making pictures.
Posted by: Gato | Sunday, 07 December 2014 at 04:18 PM
amen
Posted by: Lubo | Sunday, 07 December 2014 at 04:34 PM
Damn it! I paid a lot of money for a camera with a decent-sized sensor and a hyperfast lens rich in creamy bokeh (who the hell brought us that word, anyway?) Without a narrow depth of field, my pics could have come from a digicam or, what's worse, a smart phone. How is anybody going to know that I'm a real photographer if everything is in focus. Making art is hard. Please don't take my bokeh away! (Remove tongue from cheek.)
Posted by: Bill Poole | Sunday, 07 December 2014 at 04:37 PM
Damm Mike, there you go making sense and ruining a perfectly fun argument, all be it one me and my 5D2 have stayed on the sidelines in.
Posted by: Terry Letton | Sunday, 07 December 2014 at 04:44 PM
Thank you for posting this!
Now every time I encounter variants of this (insert adjective here) mindset in the fora, I can simply post a link to this post in reply!
Posted by: Yonatan Katznelson | Sunday, 07 December 2014 at 05:21 PM
A small collection of comments:
-You too often say, "I don't mean to criticize," or some equivalent. I find that odd in somebody who's fundamentally a critic.
-The Panasonic GH4 IS large for an m/4/3 -- until you understand that you could make movies with it. I mean, commercial movies. The m4/3 cameras designed to be basically still cameras are small.
-Camera people fall into a number of different camps -- not all are photographers. Many collectors, for example. For another, there are people who like complicated machinery for its own sake (many Leica owners also collect fine watches, fountain pens, old sports cars, etc. if you believe Leica forum talk.) I think most (not all) people who insist on large apertures may fall somewhat into that camp. I know a PJ who still shoots Nikon, but has downsized all the zooms she can to F4, because she no longer feels to need to carry a faster lens. She needed the aperture for low-light, not for Bokeh. Bokeh is not large in the PJ world. (I think she'd go to m4/3 if she could, but the equipment is owned by the newspaper.)
Posted by: John Camp | Sunday, 07 December 2014 at 05:34 PM
My guiding principle for things like this is "it's better to have it and not need it than to need it and not have it." So get the f1.2 and use f1.2 when you need it (or want it). Ditto that winter coat. Ditto whether or not you should *bring* that winter coat.
Posted by: Ed Hawco | Sunday, 07 December 2014 at 05:46 PM
I was wondering why you decided not to publish my comment about buying 1.2 lens to use it at 1.2 (and perhaps other's comments in the same vibe). And I have to say I kinda suspected some of it will be turned into a separate post.
Allow me a bit of defence though. I use a camera/lens combination that gives me depth of field equivalent in 35mm terms of roughly f1.3. That would be about f0.9 for APS sized sensors and f0,65 for u4/3 I think. For several hundred rolls of film I churned through with this set, maybe ten frames were shot stopped down.
I don't even understand the idea of inapproporiately wide aperture. There's no such thing as "too wide" when it comes to aperture. This might come from a different understanding of the term "performace", when it comes to the lens parameters. For me, lens performance judgement is based on what can I do with the depth of field when using said lens. Sharpness, contrast, aberrations, diffractions - it's all fluff. Irrelevant.
So, I paid extra premium to get the feature set I need, and I don't see no dicrepancy using this features all the time - precisely because that's what I got them for.
People scoff at the shallow dof, which I also don't get (because I love shallow depth of field obviously), but what I get very well is, people will scoff at anything. You will get scoffed at for being loaded enough to buy a Leica. For shooting with a phone camera (hell, I will scoff at folks shooting phone cameras). For whatever really. But it is kind of bashful, don't you think? Just saying, that is.
Posted by: marcin wuu | Sunday, 07 December 2014 at 05:58 PM
"I spent the first half of my life avoiding large apertures, because most lenses perform at their worst wide open."
Seems to me a more accurate generalization could be "most older lenses perform at their worst wide open, while many contemporary lenses perform best wide open or a stop down."
Simple case in point: All my older, MF macro lenses perform best somewhere around f8-f11. The Tamron AF 90/2.8 is sharpest for flat copy work at 1:2 to 1:1 wide open or one stop down, where it outperforms all the others, but ties with the Zuiko 50/3.5 Macro @ 1:2 (f8 or 11)
"And nowadays, I see lots and lots (and lots) of pictures that are taken with what I think are inappropriately wide apertures—pictures in which the photographer has reflexively tried to maximize the amount of blur, but just doesn't have everything in focus that (in my judgment) ought to be."
Amen Brother!
Posted by: Moose | Sunday, 07 December 2014 at 06:02 PM
Mike:
Agreeing with the devil, here. The camera that I'm using now – a Sony RX 10 – Is bigger then I'd prefer and is certainly larger than is possible with a 1 inch sensor. But I'm happy with it because the whole package – lens, controls, and resolution - meets my current needs perfectly.
Posted by: Steve G, Mendocino | Sunday, 07 December 2014 at 06:12 PM
It's true. People should buy overspecified equipment and feel the need to push it to its full potential in order to justify their (senseless) purchase.
This poses some interesting questions:
- Why do people demand fast lenses if, as you rightly say, the latter perform at their worst wide open?
- Why do people feel the need for 6-figure ISO values when all they will get, when shooting at such high sensivities, is something so noisy to the point of being unusable?
- And what is this 4K craze when most devices aren't ready for such high resolution?
People shoudn't buy gear on specs. They should buy whatever fulfills their needs. As I share the audiophile bug with The Editor, I'd add another example: someone buying a 600W amplifier for a 20m2 room and playing it at full volume so to use it to its full potential. Never mind if the sound would be much more pleasurable if he had bought a 50W amp: 600W is much more impressive.
Of course, not being able to use gear anywhere near its limits is an incessant cause of frustration, but people get over it - buying more gear. It's crazy, but it happens all the time.
Posted by: Manuel | Sunday, 07 December 2014 at 06:27 PM
You are right, and some people need to lighten up and stop being so bloody retentive about every last tiny irrelevant thing.
We are just trying to make nice pictures...
Technical perfection is engineering, I do that at work.
Posted by: Gildas | Sunday, 07 December 2014 at 06:53 PM
An interesting post.
I've seen this with friends and family, and for the most part, it seems to be function of being new to photography, especially in the era of "wanting to have the best".
Apropos to the fast car analogy, eventually one hopes that after getting high speed cornering and screaming down the highway 140 out of the 'system', that cruising at a moderate speed and enjoying the sound system could "click" in!
Posted by: Fred | Sunday, 07 December 2014 at 08:10 PM
I think I'm safe in saying that "I'm just sayin" needs to be retired.
Posted by: Tony Roberts | Sunday, 07 December 2014 at 08:17 PM
"This shot is just here as decor. It means nothing. Just foolin' around."
LEICA DG MACRO-ELMARIT 45/F2.8
Shot at 45 mm, f/2.8
Just foolin' around... uh huh... riiiiight.
[Don't know what you mean by this Mark...I've had the lens for about two years, bought secondhand. It's my short tele for Micro 4/3, as I mentioned the other day. So...? --Mike]
Posted by: MarkB | Sunday, 07 December 2014 at 09:30 PM
"You pay for features so they're there when you might need them, is all. And sometimes, you sacrifice certain features to get other features you need more"
Photography forum participants all over the world should take that to heart. You pay for features that you'll need, but you don't use them all the time. And to get the ones you need you often have to give up other capabilities.
There is no free lunch and there is no perfect photography equipment.
Posted by: G Dan Mitchell | Sunday, 07 December 2014 at 11:45 PM
I absolutely agree with you re. point 2, Mike - you shouls always use whatever aperture is appropriate for the shot in question, and a lens that open to f1.4 simply gives the photographer a wider range of possibilities to use. (And extra headaches, of course - not that I'm struggling a bit with my 50mm EF 1.4, oh no....)
But I disagree with your first point. Was't the very point about 4/3, and subsequently Micro 4/3, that the equipment could be smaller and lighter? Wasn't small size what the manufacturers themselves said was the format's (or formats) principal raison d'être?
Posted by: Tom Burke | Monday, 08 December 2014 at 02:30 AM
Seems pretty handy to me though. I once owned a Nikon F4!
When I first saw an F4, I found it hard to believe that it only produced a tiny 35mm negative. I have medium frmat cameras whivch are much smaller.
Posted by: Steve Smith | Monday, 08 December 2014 at 02:40 AM
Has anyone ever used every feature in a word processing program? Do you feel gipped for paying the full purchase price for features you don't need?
I can't remember the last time I've used f16 or 1/8000 on a 35mm camera, but they're probably really important to some people.
Posted by: Tom Duffy | Monday, 08 December 2014 at 04:07 AM
Hmmm. I might have been one of the people you refer to, Mike, about the Fuji 50-140.
I didn't mean to say it has to be small. But if the Lumix 35-100 equivalent is one third the weight, why wouldn't you want that?
Of the people moving from FF to smaller *sensors* for their main work, not many are doing it with *no regard* to size and weight.
If you move down in size, why settle for lenses that are way bigger than equivalent alternatives?
Posted by: Arg | Monday, 08 December 2014 at 05:56 AM
It isn't just cameras. I just bought a new Mini Cooper. Of course I read the reviews. One reviewer described it as "huge" because it grew 11cm. It may be huge, but I still can't fit a large camera bag in the boot....
Gordon
Posted by: Gordon Cahill | Monday, 08 December 2014 at 05:56 AM
With regard to large apertures, there's one blog (the over-excited puppy one), and no doubt plenty of others, where wider apertures means better bokeh and better bokeh is GREAT!! Period. FACT.
As populariser of the term I feel it's your duty to correct the misunderstanding. Time for a bokeh post?
Posted by: Don | Monday, 08 December 2014 at 06:04 AM
I guess Fuji have introduced the 50-140mm F2.8 zoom because they have Nikon and Canon firmly in their sights and their system is increasingly being adopted by professionals. I also know at least one Art Director who is very keen on razor thin differential focus, so this lens would very much suit work for him, with all the convenience of a zoom as well!
Posted by: Nick D | Monday, 08 December 2014 at 06:21 AM
I like to shoot my 50/1.4 (and other slightly less fast lenses) wide open just for the fun of it and the effect, but I realize that few fast primes are truly optimized for wide open shooting, especially at close focus. My 50 has better performance at f2.8 or f4, and with careful composition, bokeh doesn't suffer.
I suppose it's the equivalent of planning your trip so that you don't have to drive at top speed to get from A to B. You can actually enjoy more scenery. Or stop to take more and better photos.
Posted by: Earl Dunbar | Monday, 08 December 2014 at 08:19 AM
That first statement brings up strong associations with Arabic oil barons who are risking their lives by speeding in their Testarossas along dessert highways, going from nowhere tot nowhere.
Evolutionary psychologist Geoffrey Miller explains in his book Spent how consumerism works. I bought it by mistake. (The Dutch translation had my hero Darwin in the title, but in the book he was not even mentioned). Nonetheless the content is very interesting. Without diving too deep into the matter, in one of the chapters Miller explains how we are all driven in our consumer behaviour. From our times on the African savannahs up until now we are collecting things to impress our possible partners and competitors. Whether you are aware of it or not, the things you buy are demonstrations of your personality. According to Miller demonstrations of waste (1), precision (2) or reputation (3). (Hopefully I got that right, translating this back into English).
1. Waste. When you buy things that are very expensive or are clearly overdone. In case you want to become attractive by showing your wealth, your horn of plenty. I got a expensive Rolleiflex GX for example. Great camera, but even if I use it, it is often more a conversation piece than a tool. Hasselblad Lunars, Leica cameras decorated by Paul Smith or professional DSLRs with built-in motordrives used for holyday snapshots also fit into this category.
2. Precision. When you want to show your intelligence. For example: I would like to buy a Fujifilm X30. Despite of its North Korean styling it is just what I need. Fairly cheap, produces great jpgs, has beautiful colours and the resolution is good enough for 95% of my purposes.
3. Reputation. When you want to show your awareness of what is going on. Buying a certain brand because you know it is the best. Being an early adopter. Always using the cameras with the latest developments. The next Olympus E-M5II with sensor shift is already on the wishlist.
In other words: it is all about sexual selection.
Concerning that second statement, I doubt if that winter coat protecting you for minus 30 degrees is attractive enough to suit that purpose.
Posted by: s.low | Monday, 08 December 2014 at 09:43 AM
@ Tom Duffy Has anyone ever used every feature in a word processing program? Do you feel gipped for paying the full purchase price for features you don't need?
I discovered incredibly simple word processing programs for iPad. Writing text is, miraculously, reduced to writing some text. The few features are welcome, elegantly presented and feel natural.
I stopped using the word processing program, as I grew more and more frustrated by features i need being randomly hidden in obscure places and features I don't even know existed are easily triggered by accident and wreck the document.
Posted by: jerome | Monday, 08 December 2014 at 10:36 AM
Strange how your comment provokes another thought As you know I photograph railways. So in the film days you'd open the lens all the way to enable the fastest possible shutter speed (to stop the moving train) in dim light.
With digital you simply increase the ISAO(ASA) reading and set the aperture to f/8 and record the image
and a higher shutter speed and stop themoving train.
Problem for me is such a possibility takes all the fun out of photography IMO. The technicalities in being able to use the film standard for image recording as it was is so much more fun.
Hence have acquired a friend's (he has moved onward to digital Olympus) screw mount Pentax camera collection.
Am moving back to my roots so to speak. Photography is for me, not others.
Posted by: Bryce Lee | Monday, 08 December 2014 at 11:16 AM
Side note to Gordon Cahill: the new Mini Cooper *is* huge when compared to the original Mini-Cooper. Way more than 11 cm.
Posted by: Ed Hawco | Monday, 08 December 2014 at 03:10 PM
Patrick Perez wrote:
> In defense of a fast lens is another reason separate from ever shooting
> wide-open: the fact it will help the autofocus in lower light levels
A superficially seductive, but generally incorrect thesis.
Phase-detect AF (PDAF) systems, used on DSLRs and some mirrorless cameras, use two small areas located on a "light ring" on the lens' "entrance pupil".
The "entrance pupil" is the quasi-circular opening formed by the apeture blades, as observed from the front of the lens.
The entrance pupil of a lens that has, say, a 56mm focal length, and a f/4 aperture, will be a disk whose diameter is 56mm/4 = 14mm.
That entrance pupil can be considered to be the physical manifestation of an abstract light cone, whose base is a disk that is 14mm in diameter, and whose height is 56mm.
Similarly, the entrance pupil of a 56mm f/2.8 lens would have a diameter of 56mm/2.8 = 20mm.
Mentally "remove" — or "carve out" — the f/4.0 light cone from the f/2.8 light cone to obtain a "hollow" f/2.8 light cone. At the entrance pupil, this hollow light cone would then delineate a ring, instead of a full disk. The ring's outer diameter would be 20mm, and the inner diameter would be 14mm.
A f/2.8 PDAF sensor uses two or more patches on that ring, located at diametrically opposite locations, as "vantage points" from which the PDAF sensors observe the subject, performing a measurement equivalent to a "triangulation" to determine the subject's distance.
The important point is that the light cones, and equivalent rings, defined by lenses with apertures larger than f/2.8 aren't used at all by the f/2.8 PDAF module.
Thus, lenses faster than f/2.8 don't help a PDAF system at all, regardless of the light levels.
Lenses slower than f/2.8 obviously can't delineate a f/2.8 ring on their entrance pupil, and the f/2.8 PDAF sensor would then be blind and useless, making AF impossible. Hence the need for an additional set of PDAF sensors, angled such that they observe the subject from vantage points located on the entrance pupil's f/5.6 ring.
As the distance between the patches on a f/5.6 ring would obviously be half that on a f/2.8 ring, the "base length" used in the equivalent triangulation is halved, and the measurement accuracy is correspondingly lower. A lower-accuracy AF, however, is obviously prefereble to having no AF capability at all with lenses slower than f/2.8.
As for the contrast detect AF systems used by many mirrorless cameras, they might benefit from the increased light-gathering ability of faster lenses. Note, however, that many (most ?) mirrorless cameras operate their lens at the working aperture, which means that a fast lens, if stopped down a few stops, would confer no brightness or AF accuracy advantage over a slower lens.
Posted by: Bruno Masset | Monday, 08 December 2014 at 08:06 PM
Arg wrote:
> I might have been one of the people you refer to, Mike, about the Fuji 50-140.
> I didn't mean to say it has to be small. But if the Lumix 35-100 equivalent
> is one third the weight, why wouldn't you want that?
Yes, but the (excellent) Lumix 35-100 is a f/2.8 lens for the MFT format, which makes it not exactly equivalent to a f/2.8 lens for the APS-C format.
As the Fuji f/2.8 APS-C lens has a light output about 1.7 times larger than the Lumix f/2.8 MFT lens, it's understandable that their sizes are quite different.
Posted by: Bruno Masset | Monday, 08 December 2014 at 08:22 PM
...pictures in which the photographer has reflexively tried to maximize the amount of blur,...
Indeed. And can we add to that another widespread affliction: over fondness in ultra-wide angle zooms? Seems to me I see way too many pictures these days "in which the photographer has reflexively tried to use the widest possible angle", often with terrible composition as a result.
Or try this specific landscape photographer's variant: "pictures in which the photographer has reflexively positioned the widest possible lens at the lowest possible distance from both the ground and an insignificant feature of the environnement, while using every possible trick to maximize depth-of-field". That was fresh and different 10 years ago, but now it's just a boring recipe in most cases.
Not to be misunderstood: there _are_ beautiful photographs done with UWA. Only it's genuinely difficult.
Posted by: Vinck | Monday, 08 December 2014 at 11:41 PM
Well, count me as one who believes mirrorless should be small.
If I give up an SLR- a device with a viewfinder having infinite resolution, infinite dynamic range rendering from light to dark, a realtime rendition of the outside world without jaggies or tearies or any kind of -ies; if I'm going to give up the fastest autofocus and the longest battery life, I need something in exchange.
In exchange for the bulk of pentaprism and mirror box, I want nothing. That is, in exchange for those analog benefits, and the resulting infrastructure that supports them, I want the resulting vacuum to be shrunk to nothing. Which means, I want a camera that is smaller and lighter.
In giving up lenses that are fully optically corrected for ones that are corrected highly in software, I want smaller and lighter lenses.
If I'm going to a smaller format, I want smaller cameras and lenses.
And did I mention... I want cheaper cameras and lenses. Except the funny part is, mirrorless is not cheaper.
That's the way I roll.
Posted by: ronin | Tuesday, 09 December 2014 at 04:10 PM
@Bruno
Most (all?) mirrorless and compact cameras both meter exposure and do AF with the lens wide open with the sensor in one of its video modes.
Some of them you can see the aperture changing in use: at selected aperture then wide open for metering and AF then back to selected aperture to take the image. Particularly easy to see this in an X100 where the aperture blades are very close to the front of the lens.
It makes sense as its a win in two ways as it reduces the DoF of the lens and increase the amount of light (so reducing photon count noise). Both help CDAF to converge on a focus solution more quickly and more reliably. The reduced noise helps most with marginal contrast targets or low light.
Posted by: Kevin Purcell | Tuesday, 09 December 2014 at 04:26 PM
The good thing about a car that does 140 is that they are often safer, quieter and have more in reserve when you are doing 70-80.
Similarly, I often find F1.4 lenses work well at around F2.8 to F4. At F8 they are a waste of money, which is why I tend to use the F1.8 primes for landscape and street work.
Modern photography is littered with fashionable attitudes which make no sense to me. I generally have what I need to cover the bases and no more, one of the reasons I like Fuji cameras. They don't have many features which I don't use.
Posted by: Steve Jacob | Tuesday, 09 December 2014 at 09:02 PM
@Kevin
> Most (all?) mirrorless and compact cameras both meter exposure and do
> AF with the lens wide open with the sensor in one of its video modes.
I stand corrected. In my defense, I was probably misled by my being suprised seeing the semi-closed aperture blades of an Olympus 75mm F/1.8 MFT lens on a friend's camera. Reminiscing, it may be that it was a special situation where the camera needed to close down the aperture a bit to regulate the light amount reaching the sensor, as we were under blazing sunlight.
@ronin
There's no intrinsic reason why a DSLR's AF would necessarily be faster than a mirrorless'. Sony's TLM half-mirror, after all, has the same architecture as a DSLR's PDAF module.
Anyway, advantages of an EVF — i.e. a mirrorless — over an OVF — i.e. a SLR — that are unrelated to camera size also include:
- More accurate DoF preview.
An AF SLR typically has a matte focusing screen that's far less "matte" — i.e. less diffusive — than a manual-focus SLR's. AF SLRs redirect about 30% of the incoming light towards the AF module. Furthermore, the market nowadays is skewed more towards fairly dark, consumer zoom lenses of the F/3.5~F/5.6 variety than fast primes. On APS-C DSLRs, increasing the finder magnification so that the finder image doesn't look too ridiculously small compared e.g. to film SLRs or full-frame DSLRs also decreases the finder brightness, as the same light energy must be spread over a larger spatial angle towards the photographer's eyeball.
All these factors have led camera manufacturers to increase the finder image's brightness by making the focusing screen more transparent — and therefore brighter as less of the lightrays are diffused in random directions that don't reach the photographer's eyeball. A fully transparent glass surface — e.g. a window pane — obviously cannot be used to focus a picture, or appreciate DoF. Similary, the more transparent focusing screen of AF SLRs sacrifices some of the ability to judge DoF. Furthermore, DoF "previews" on an SLR aren't really that useful, as the picture often becomes too dark or grainy to be reliably able to judge the DoF.
An EVF, OTOH, can provide an accurate preview the actual DoF, while automatically compensating the brightness loss caused by a stopped down aperture.
- More accurate white balance preview.
- More accurate exposure preview.
I don't chimp, but regretted it a few times when I had forgotten to put my DSLR's metering mode back from spot mode to the usual center-weighted average mode, and discovered it only too late when inspecting the resulting image files back home on the computer...
- No mirror slap, and thus less camera vibration, resulting in potentially sharper pictures.
- No mirror slap typically means a more silent and more discrete camera, which could be useful in some situations.
- No moving mechanical parts, like the AF submirror hanging under the main reflex mirror, that could go a few tens of microns out of alignment after a few thousand mirror up/down cycles, and affect the focusing accuracy in an era when pixel pitches are in the single-digit micron range.
- Accurate manual focusing, as the focusing on an EVS is, obvuously, WYSIWIG. An SLR's focusing screen, OTOH, especially if it's exchangeable, can have a positional error in the tens of microns that can cause a significant mismatch between the finder and actual picture's focusing planes.
- The EVF picture can easily be set to increased magnification modes to assist precise manual focus.
- Less shutter lag — i.e. shorter delay between pressing the shutter button and the actual start of the image capture. The need to accelerate from standstill some mechanical components with a certain inertia like the reflex mirror is obviated on mirrorless cameras. As per imaging-resource.com's measurements, a Sont NEX camera, for example, has a shorter shutter lag than a pro-class Canon 1D DSLR. Also, the electronic first curtain mode available on some mirrorless cameras would also contribute to reducing the shutter lag and vibrations.
- On mirrorless cameras with IBIS, the viewfinder image — as well as the picture taken — can be stabilized with all lenses, including e.g. the Cosina/Zeiss 135mm F/2.0 — a.k.a. the closet Otus, — or oldies / goodies from the film era like some Leica Apo-Telyts.
- With a DSLR, the viewfinder image e.g. in backlight situations, or in extremely bright envronments like beaches, ski slopes etc. can become so bright and contrasty that the various data displays at the periphery of the finder are completely drown out, and become unreadable. This can be quite frustrating, as these are typically the situations where the indications of the camera's exposure meter set e.g. in spot metering mode would be useful, if only they were readable.
The exposure parameter displays in an EVF, OTOH, can reach the same maximum brightness as the viewfinder image proper, and it's thus impossible for the contrast to become so high as to make the indications unreadable.
Posted by: Bruno Masset | Wednesday, 10 December 2014 at 01:59 AM