50mm

<p>Hi, I have been doing some reading on past forums about the canon 50mm 1.4. It sounds like a reasonable lens, however in one forum, someone mentions there is a bend in the resulting photograph with this lens. I was just wondering if this person has bad luck, and maybe their lens was defected, or is this true for all of the 50mm 1.4. Thanks for your time.</p>

<p>John, I have no idea what this guy could mean by "bend." Perhaps it's his brain that's defective.</p>

<p>The EF 50/1.4 has one of the finest optical formulae ever devised for a normal prime lens. Canon introduced the formula with the FD 50/1.4 (and the F-1) in 1971, and, almost four decades later, has had no need to change it.</p>

<p>Unless you're willing (and able) to shell out for the EF 50/1.2 L, the 50/1.4 is a no-brainer.</p>

<p> </p>

<p>Well he had a picture of it, ill go back and see if I can find the link, but thank you.</p>

http://www.photo.net/canon-eos-digital-camera-forum/00UKbB

<blockquote>

<p>The EF 50/1.4 has one of the finest optical formulae ever devised for a normal prime lens</p>

</blockquote>

<p>Well, I can name at least four or five 50 mm lenses way finer in the <em>optical formulae</em> department. Still the <em>optical formulae</em> of the EF 50/1.4 is OK (not great wide open, but OK above f/2) but its <em>mechanical formulae</em> stinks to high heavens and has always stunk: fragile, temperamental and easy to break piece of equipment. My only Canon lens that needs to be treated with utmost care.</p>

<p>The lens shows a small amount of barrel distortion but it isn't really a serious issue. The lens is also soft and a bit low contrast at f/1.4, but improves greatly by f/2 or slightly earlier.</p>

<p>I use the lens and like it a great deal.</p>

<p>Dan</p>

<p><em><strong>"Hi, I have been doing some reading on past forums about the canon 50mm 1.4. It sounds like a reasonable lens, however in one forum, someone mentions there is a bend in the resulting photograph with this lens."</strong></em></p>

<p>In the link you supplied the first image (red bricks) shows what appears to be Barrel Distortion across the top of the frame and pronounced toward the edges. – I.e. the top line of bricks are bending downward at the edges</p>

<p>Barrel Distortion is a common lens attribute – and most of the time it can be corrected easily in post production.</p>

<p>The EF50F/1.4 presents with some Barrel Distortion.</p>

<p>Barrel Distortion is worse, at the edges of the lens’s Image Circle</p>

<p>Taking only the first image (Red Bricks):</p>

<p>> It was shot with a 5D – using FULL image circle of the lens<br />> It was shot at about 8ft SD.- i.e. Close to the subject (based on full crop / bricks 9 inches)<br />> The camera viewpoint is elevated thus foreshortening top of frame (we can see the ledge)<br />> The camera is NOT at right angles to the wall (we can see the ledge)</p>

<p>These four factors can exacerbate the appearance of the barrel distortion at the top edge fot hat image.</p>

<p>These facts , and a description of what Barrel Distortion is, might have been mentioned on that thread – I didn’t read it - I just looked at the first image and analysed it.</p>

<p>***</p>

<p>If you want a Canon 50mm lens with less barrel distortion then buy the EF 50mm F/2.5Macro.<br>

However I find the EF50mmF/1.4 a good performer.</p>

<p>I do note the issue with mechanical fragility, and I treat mine with care too, but then again I don’t play football with any of my lenses.</p>

<p>It seems that a front on knock (or drop) to the 50F/1.4 can break a little cam which basically stuffs it – you can do a search there are many discussions about it, and various degrees of passion. <br />

<p>WW</p>

<p> </p>

</p>

<p>My Canon EF 50mm f1.4 does have some small amount of barrel distortion but I am always happy with the results. The lens is not too sharp wide open but fine at f2.8 as to the build quality I too wish Canon would do us all a favor and redesign the mechanics, its worse than poor. May be Canon does not have the time after all we need a new DSLR every four month more than a reliable working lens.</p>

 

<p>Michael, "formulae" is the plural form of the word "formula."</p>

<p>And if you can name only four or five normal primes that are better than EF 50/1.4, then it must be a very fine lens, indeed.</p>

<p>Incidentally, the EF 50/1.4 may not have the best build quality, but the FD 50/1.4 is superbly built. So <em>Canon's </em>normal primes haven't always been mechanically challenged.</p>

<p>thank you for all your help, now i have some pro's and cons to weigh out.</p>

<p>It's more than reasonable; it's a wonderful lens. The barrel distortion gets worse the closer you focus. It's normal behavior for this kind of lens, which is literally a classic. Telescope maker Alvan Clark first made it in the late nineteenth century and in one variation or another has been a standard of pretty much every lens manufacturer. It's incredibly sharp by f/2.8 and still no slouch at f/2.0. Wide open it loses contrast, but this is not necessarily bad: for portraiture it's very attractive, I think. I tend to use it around f/2.0 - f/2.8 and always marvel at the result. If you use a hood (sold separately) you protect the reportedly delicate front barrel from knocks. I've not had any mechanical problems, but if you search the web for them, there are plenty of reports of the internal motor clutch going kaput because of shock to or stress on this part.</p>

<p>"Bend" a nice alternative to the word distortion, I might use it in the future, hehehe</p>

<p>john,</p>

 

<p>Here’s my breakdown of the 50s:</p>

 

<p>Every photographer should have a 50 f/1.8 in every camera bag. It’s so cheap and such

a delightfully wonderful lens, it’s a no-brainer. Even if you’ve got some other 50 you

prefer, the f/1.8 is the ideal backup. You can buy a half dozen of ’em for what you’d

pay for many other lenses, so questions about how sturdy it is are largely moot. If you drop it and it

breaks rather than bounce, it’s still cheaper than the “protection” filter

you’ll find permanently attached to most rich doctor’s lenses.</p>

 

<p>So long as you don’t need faster than f/2.5, the macro is the best 50 Canon makes.

It’s sharp enough to slice tomatoes, and there simply isn’t any distortion. Color and

contrast are as good as it gets.</p>

 

<p>If you need faster than f/1.8 — and those who do are in the minority — then the

choices are simple: the f/1.4, unless you need the f/1.2, unless you need the out-of-production f/1.0. Stopped down to f/2 — and certainly by f/2.8 — it’ll be all but impossible to tell the difference

between any of the lenses. Yes, it can be done, but, for all practical purposes, the lenses are

identical stopped down. You don’t get an expensive fast lens for its performance stopped

down; you get it to shoot wide open.</p>

 

<p>So, short version: get the f/1.8, no matter what. If you also need something more, get the macro

for the image quality, or one of the fast ones to shoot wide open.</p>

 

<p>Cheers,</p>

 

<p>b&</p>

<blockquote>

<p>EF 50/1.8 EF 50/1.4 (...)Stopped down to f/2 — and certainly by f/2.8 — it’ll be all but impossible to tell the difference between any of the lenses.</p>

</blockquote>

<p>Except in such details as quality of OOF parts - due to different number of aperture blades, quality of coating, etc. You know, the EF 50/1.8 stands out only in the sea of mediocrity of the Canon's "old school" consumer zooms.</p>

 

<p>The Canon 1.4 is an excellent lens. Not as sharp as old Minoltas but close. It suffers from erratic focusing to a minor degree (this is a much more significant problem on the Canon 50mm 1.8).</p>

<p>The 50mm 1.4 is on my Canon SLR 90% of the time.</p>

<p>Here are some comparisons done om TMAX 100 at different apertures at the center and corner (21MP scan with Coolscan 9000). As you can tell the autofocus of the Canon lenses failed in several instances.:<br /> http://shutterclick.smugmug.com/Other/Standard-Lenses/9379726_tZVrK#633634184_TGWGV-O-LB</p>

<p> </p><div></div>

<p>Get the Sigma 50mm F1.4 EX DG, it's has to be the best 50mm after canon's EF 50mm F1.2L, it costs a bit more than the EF 50mm F1.4 but the higher price is money well spent, the image quality is way better when shooting wide open.</p>

<p>Mars, I was of course playing dumb when I said I had no idea what "bend" meant in the original post. It was obvious that he was referring to barrel distortion. And I really like your suggestion that the word "bend" be used as a synonym for distortion. It has an unpretentious, down-to-earth ring to it.</p>

<p>Steve,</p>

<p>Very few comparison testers have favoured the Sigma outright, I haven't actually seen any. Most agree the Canon 50 f1.4 is sharper in the center wide open with comparatively soft edges, whilst the Sigma is not as sharp in the center wide open but is more even and has better edge performance. Who cares about stopped down, if you do then get the macro 50.</p>

<p>I have the Canon 1.4, I got it before the Sigma came out but to me the whole point is wide open portraiture, I don't care too much about edge sharpness but the eyes have to be as sharp as possible, the Canon, apparently, delivers that better.</p>

<p>I had and sold a 50 1.8 Mk I, as it was pretty useless at anything lower than 2.8. The AF of the 50 1.8 on a T1i was too erratic. The 50 1.4 is not supposed to be much better in the AF department, so I will wait for an update or get a Sigma if I can't live without an AF fast 50. I can deal with a little softness at 1.4, but not the focal plane being off by too far. For 1.4 to be trustworthy you may need to use magnified live view and manual focus.</p>

<p ><strong ><em >"I have the Canon 1.4, I got it before the Sigma came out . . ."</em></strong></p>

<p > </p>

<p >Similar to Scott I did too; but if I were buying now I would still favour the Canon 50F/1.4 over the Sigma, for the "Wide Open" reasons Scott has mentioned - but also, for the extra $ spent on the Sigma I can just about buy the EF85F1/8 or the EF35F/2. So for "kit thinking" the EF50F/1.4 is a more logical choice, IMO.</p>

<p > </p>

<p >Also, the Sigma is 77mm Filter (I think - well I do know it is big), and the Canon is 58mm - sticking with a 58mm Filter size might be relevant if one has other Canon mid Priced Prime Lenses and uses high quality CPF or ND Filters, for example.</p>

<p > </p>

<p >I do not have any (more) difficulty with the AF of my EF50F/1.4 in low light, than say the EF 85F/1.8 or the EF35F/2 just as examples </p>

<p > </p>

<p >I think many reported “difficulties with AF” stem from not understanding fully how AF works and what its limits are in low light / low contrast. Also many complaints stem from not fully appreciating how to make best use of the AF system in low light or low contrast situations. </p>

<p > </p>

<p >Techniques applicable to various shooting scenarios, to get better AF in low light or low contrast include, but are not limited to: using centre point only; MF with AF light to confirm; Flash AF assist; Zone Focus; Focus and Recompose.</p>

<p > </p>

<p >Also many folk do not understand AF peculiarities which some the EOS cameras have: the Centre AF square when viewed in the 20D’s viewfinder, is often a little higher than the actual AF point – is one example. </p>

<p > </p>

<p >WW </p>

<p > </p>

<p>The tests at DPreview and Photozone look pretty conclusive, the Sigma is simply superior in the corners and center at wide apertures. The Canon has no advantages aside from price. If the AF points on Canon cameras are as inaccurate as William suggests, this could explain why the AF on the lenses at wide apertures are so dodgy. </p>

<blockquote>

<p>If the AF points on Canon cameras are as inaccurate as William suggests, this could explain why the AF on the lenses at wide apertures are so dodgy.</p>

</blockquote>

<p>Well, if the AF markers and the actual AF area ("point" is a misnomer here) don't match then the cameras is out of whack, regardless of the brand. As for "dodgy" AF of f/1.4 lenses this is a multifaceted issue ranging from documented issues with some camera/lens combos to bodies/lenses not adjusted properly to user errors (a nod of the model or a slight aft/fore movement of the photographer blows DOF, which can be a few milimeters to begin with, at f/1.4.)</p>

<p>The Photozone test for the Sigma 50mmF.1.4, I have seen, I believe reference an APS-C: so Corners / Edges are not "real" Corners / Edges. <br>

<br>

The DPreview test I have seen does do Res. at both 135Format and APS-C format - but I am not convinced that the DPreview is "pretty conclusive" as a <strong ><em >comparison test</em></strong> (i.e. an A/B <strong><em>two </em></strong>lens test) Sigma Vs. Canon. I think that was the point Scott was making, at least that is how I understood and responded to his comment.<br>

<br>

Perhaps there are other tests done by these companies, of which I am not aware. <br>

<br>

We are in the area of picking nits, IMO, which is OK - but perhaps beyond the practical for most buyers. But none the less the point that many (recent) lens tests are done using APS-C bodies is one to make I think, particularly as we are discussing two, 135format, lenses.<br>

<br>

But the main thrust of my previous comment was to highlight the extra initial cost and possible additional costs of buying the Sigma 50mmF/1.4 vs. the lesser priced Canon 50mmF/1.4. </p>

<p > </p>

<p > </p>

<p >WW</p>

 

<p>Stephen,</p>

<p>I'd hardly call that conclusive, DPreview are loosing credibility by the truckload (I didn't download their "widget" so I could do comparisons though, no way do I want their software on my computer) and Photozone only tested the Sigma on a crop camera.</p>

<p>Many owners who are not wrapped up in their new purchase also don't agree, here is one.</p>

<p>http://www.pbase.com/peter_dumont/sigma_50mm_f1_4</p>

<p>And this comparison simply shows your opinion to be incorrect, look at the contrast at 1.4 at the edge on the Canon.</p>

<p>http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?CameraComp=0&FLIComp=0&APIComp=0&Lens=473&Camera=453&Sample=0&FLI=0&API=0&LensComp=115</p>

<p>Now Sigma are well known for their quality control inconsistencies, even more so than Canon, so the differences of opinion on the internet might well be due to sample variation, who knows.</p>

<p>The Canon 50mm f1.4 is a very good little lens that does what it is supposed to do very well. The barrel distortion that John originally asked about can be easily corrected, if it is intrusive or unwanted, in post. The lens is not designed to be a super accurate flat field no distortion lens though, it was designed to be a mid range (price and featured) fastish "standard" lens on 35mm film cameras. It has never been the fastest or most expensive 50 Canon have sold, it has always had a Macro cousin for those with other priorities too. I probably own 10 Canon 50mm lenses in their various speeds and specialities, the 1.4 is the one I grab almost every time.<br>

Hi there WW :-)</p>

 

<p>I am not sure about the camera being necessarily "out of whack" - to the extent that is might be able to be "fixed"</p>

<p>All human design, machining and manufacturer is within limits - tolerances.</p>

<p>The "out of whack" I referenced peculiar to the 20D is usually of little consequence, but can have an adverse impact when using a WA lens, for example - there are threads on this forum citing this peculiarity and this symptom has been noted by very experienced Photographers - but I suspect (I don't know for sure) is still with the tolerances of the AF system as specified by Canon Engineering.</p>

<p>I agree entirely that “dodgy AF” is a multifaceted issue – and I agree that, added to my list above, NOT understanding Depth of Field, is another issue and is right up the top of the list.</p>

<p>Also some lenses and cameras and combinations of both, perform better (or worse) than others - yes. <br>

<br />WW</p>