Sigma 18-35mm f1.8 DC HSM reviews

<p>Two full measurement based test, that correlate corroborate each-other in the main<br>

One review I posted the link to days ago.<br>

<a href="http://slrgear.com/reviews/showproduct.php?product=1609">http://slrgear.com/reviews/showproduct.php?product=1609</a></p>

<p>Here is a Lenstip review posted today<br>

<a href="http://www.lenstip.com/374.1-Lens_review-Sigma_A_18-35_mm_f_1.8_DC_HSM_.html">http://www.lenstip.com/374.1-Lens_review-Sigma_A_18-35_mm_f_1.8_DC_HSM_.html</a><br>

The summary</p>

<center></center>

<p><strong>Pros:</strong></p>

<ul>

<li>solid and stylish casing,</li>

<li>simply brillant image quality in the frame centre,</li>

<li>very good image quality on the edge of the frame,</li>

<li>sensibly corrected chromatic aberration,</li>

<li>negligible spherical aberration,</li>

<li>moderate distortion for a zoom lens,</li>

<li>slight astigmatism,</li>

<li>silent and accurate autofocus,</li>

<li>rich accessory kit,</li>

<li>good price to ability and quality ratio.</li>

</ul>

<p><strong>Cons:</strong></p>

<ul>

<li>weak work against bright light.</li>

</ul>

<p>You should congratulate the Sigma Corporation and their optics specialists for two reasons. Firstly for their courage – they attempted to produce an instrument no other company had tried to construct before. Such a situation a lot can be forgiven so their product didn’t have to be outstanding. Still it is obvious Sigma wasn’t contended with half measures; not only they manufactured a unique instrument but also made it optically excellent in many categories.<br>

What’s important, I am sure there would be those willing to pay 4,000 – 5,000 PLN for such a lens and Sigma, taking into account the lack of competitors, could demand easily such an amount of money; however the company didn’t decide to follow that strategy and suggested a price which is within the reach of many amateur photographers. That’s why I don’t doubt that, like the Sigma 35 mm f/1.4 EX HSM, the 18-35 mm f/1.8 model won’t stay long on the shop shelves.<br>

Despite the slip-up during the work against bright light, taking into account all the achievements of the Sigma and its price we don’t doubt it deserves the badge below. Congratulations!</p>

<p>Some of these results were better than separate primes like the Nikon 35mm f1.8 known as <br>

a great lens for the money. My takeaway is that this is one sharp fast AF lens.</p>

<p>Can a moderator please fix the subject? </p>

<p>I agree, I will try next time to catch all the Typoos, OOPS. I would appreciate Shun<br>

if you could do what Rob suggested. We are trying to just provide info for those<br>

who are following this product. Of course a Photo.net review would be desired,<br>

I read the Sigma 35mm review. I like the fact that this review is from Poland, the whole<br>

world is interested just like photo.net I guess we are up to at least 8 pages on that other<br>

thread on the same lens.</p>

<blockquote>

<p>"never in our wildest dreams had we thought that the resolution results of this lens would be so sensational. We thought that a new construction, difficult to design, would be full of compromises, sometimes necessary to swallow if you want to own an f/1.8 zoom lens We are happy to announce we were wrong. When it comes to the resolution there are no compromises almost at all and the lens provides you images of great quality practically for every combination of focal lengths and apertures."</p>

</blockquote>

<p>that's from the lenstip review. i'd want to see what photozone and dpreview have to say, but in general, reviews dont get much more glowing than that. is this lens a game-changer? could be. if you shoot DX and already have 1.8 or 1.4 50 and 85 primes, the 18-35 could be a perfect piece of kit, particularly for event shooters, PJs and anyone else who needs blurred backgrounds or low light ability. i was intrigued before; now i'm <em>interested</em>.</p>

<p>And from this I get what if I buy it, since I already have the Nikon 17-552.8? My wife pays attention 'a little' ... money is not a real issue, but if I 'double-down' ....??? Gotta stay at least a legs length away for awhile to avoid an ... well, some kind of kicking...;-)</p>

<blockquote>

<p>from this I get what if I buy it, since I already have the Nikon 17-552.8?</p>

</blockquote>

<p>i'd wait for reviews in Nikon-mount before buying, but if they have similar findings, i'd sell the 17-55 (you should be able to get the asking price of the sigma), and gain a stop-and-a-third of aperture and what may be class-leading performance. if you're really attached to the 17-55, and/or would miss the 35-55 range, sure, keep it. but the 17-55 is a design from 2003; the sigma's high resolution figures, especially sub-2.8, are likely the result of making a 2x zoom, as opposed to a 3x zoom. tokina did the same thing--lower the zoom range--with their 11-16, which has what is often described as prime-like performance, so it's not totally unprecedented.</p>

<p>Today's issue (for me, in the mail) of <em>Popular Photography</em> has an announcement of the lens:<br>

http://www.popphoto.com/gear/2013/06/sigma-18-35mm-f18-zoom-lens-will-cost-just-799 </p>

<p>This sounds interesting at a good price. Sigma seems to be following a very intelligent (IMHO) strategy of pushing the envelope into places the Canikon companies are slow in getting to. Good for them.</p>

<p>Eric, you and I have read lots of lens reviews, the review measurement numbers speak for<br>

themselves, so far we got numbers from the 2 different sources, I too would like<br>

to see photozone.de, but since I placed an pre-order, each test assures me more and more<br>

that this won't be a big flop of a purchase.<br>

I looked at all the picture posted so far on Dpreview, that Korean sight, the Slrgear sight,<br>

etc. They looked good. I like that this test review the Bokeh, and said it was fine, that is<br>

important, as much so as good edge resolution and all the tests where we can get numbers.<br>

For the fastest zoom available it breaks new ground, but the numbers put this on par<br>

with fixed fast primes, and that is really a DX game changer.</p>

<p>while as a night shooter I am interested in this lens, I am trying to avoid adding "pieces" to my system. I currently am using Tokina 11-16mm f2.8, Nikons 17-55mm f2.8, 70-200mm f2.8 VR on my D7100 and D5100. The 17-55mm is my most used lens, so I don't want to dump it. I'm not sure how often I'd use something wider than f2.8 either. SO, without a clearly identified need, I will pass on the lens for now, even if it is as excellent as it sounds. I just don't have a "job" for it. Now if they come up with a 17-50mm f1.8, hmmm...........</p>

<p>Kent in SD</p>

<p>So as a night shooter, you don't think that an extra 1.25 f-stop faster won't make<br>

for less high iso noise, a higher shutter speed or a lower iso? I think it helps<br>

narrow the difference between FX and DX in night photography. If that was<br>

the type of environment I shot photos in I would be shooting FX gear, just buy one<br>

FX camera body instead of two DX bodies. <br>

I always preferred fast lenses, was never crazy for slow zooms that averaged f4.5<br>

I have F1.2, and f1.4 prime lenses, and a couple of medium fast f2 prime lenses<br>

bought for indoor available light shooting. This f1.8 lens would have been a dream come <br>

true when color film went maybe to ISO 800.</p>

 

<p>Sorry to rain on your parade, but I think this lens will be a touch sell. For one thing the zoom range is odd for DX, and if I want f1.8 for low-light work, I would use FX, which is getting cheaper and cheaper. I have mentioned before that a relative of mine recently bought a brand new Canon 6D for around $1500. I think we'll see the D600 and its successor in that price range within a year.</p>

<p>Nikon will continue to sell a lot of DX-format DSLRs, but those will be mainly consumer-grade, sub-$1000 D3200 and D5200 types. It'll be difficult to get those owners to spend $800 on a wide zoom. I don't see any more D300-class DSLRs from Nikon.</p>

<p>I happen to love higher-end DX cameras, but only for telephoto and super telephoto work. I use the D7100 very often with 400mm lenses and up. For any wide-angle work, FX is the answer.</p>

<p>IMO, this lens is mis-guided approach from Sigma. Canon and Nikon will not bother with an f1.8 wide zoom for APS-C DSLRs.</p>

<p> </p>

<p>'Tough Sell'? Maybe, maybe not. Stopped by my local store yesterday to give them some work. They are small by any standard, but have loyal customers, are an HQ outfit, and have been in business for 99 years. While talking about the 'work' ... they asked ME if I'd heard about this new lens ... they volunteered THEY had 27 preorders ... in WED, THURS, FRI, SAT. of last week alone, all local, no net stuff. "Mr. Brown, we have not had that kind of traffic since my Grandfather was running the store back when ... and Polaroid came out with their first 'instant' camera." When was that, early 50's or so?Feeding frenzies subside ... we will see if this one does, but judging from traffic on other net sites...and commentary on those sites, and this one .... hmmmm, I dunno. </p>

<p>A lot of people can't afford FX, and still have family (often the children are the reason why they can't afford FX), they want to do environmental portraits, and events where they would like to use wide angles even in low light. A lot of newcomers who buy DSLRs to document their children growing up don't have the skills to use flash well (in my opinion it takes many years to master lighting; after 20 years in photography I wouldn't make the slightest claim of mastery of lighting), so they tend to prefer available light where they can. Nikon's entry level DX cameras have significant problems with the preflash timing which basically close the subject's eyes just in time for the main exposure with a very high frequency when the flash is the dominant source of light (to avoid mixed color lighting), a problem that doesn't exist with the D7000 and higher end cameras. I have a friend whose family basically don't use flash for this reason (D80); they can't use manual flash well and TTL gives systematically closed eyes. They could either upgrade the camera to a more expensive model and spend a lot of time learning flash or just obtain a fast wide angle lens for their family events (it is a large family and they often have other kids over, so there is a lot of activity to cover, and 35mm is just too long for many shots). </p>

<p>DX cameras are still widely used for PJ work, especially in less affluent countries. I think this zoom will sell in very large numbers, five digits for sure, probably not millions given that price. Without it DX is limited in its applicability, quite unnecessarily in my opinion.</p>

<p>It is quite possible that Nikon and Canon won't make f/1.8 zooms for DX, in response to this lens, but I hope they make at least one fast wide angle prime, which could be a 23mm or 18mm f/2, f/1.8, or f/1.4. It is badly needed and has been for over a decade. FX may be the solution in 10 or 20 years when the price of the camera has gone down, but for now, at least a few generations of DX are still needed so that people can get started and are not restricted to tele work mostly (a ridiculous limitation given that typically the best photographs are made at a close distance to the subject, and the fact that a lot of people spend most of their time indoors).</p>

<p>For night shooting I'm not all that blown away - f/1.8 is nice, but it's not like there aren't f/1.4 primes - but it certainly has its uses, and I'm glad to hear good things about the performance. I agree that a 2x zoom seems to be within the bounds of what can be made as good as a prime - hence the 14-24, for example.<br />

<br />

Shun: I can't speak about your friend's deal, but in the UK the D600 is about £100 cheaper than the 6D in most places. Though that price is "£ = $", so don't get too excited. I'm interested that you suggest that the D600 will be replaced relatively soon - on a consumer camera schedule, rather than on an FX sensor schedule. I'm not sure what I expect here, but I'll look forward to finding out!<br />

<br />

It's looking like the "lens of the year" competitions are going to be interesting. Lest anyone think it's a slam-dunk, Zeiss's 135 looks pretty impressive as well, and I'm looking forward to their normal lens getting tested too. Fun times.</p>

<p>Tough sell, maybe in the future DX won't be as advantageous as it is now. Maybe in the<br>

future FX will catch up to the unit sales cameras like the D7000 sold per model.<br>

But, lets not forget that DX was all Nikon sold us for years, and then when FX sold<br>

for years it was too expensive for regular hobbyists. There are a lot of<br>

DX cameras out there and many like the D300 could use a lens<br>

that is 1.25 f-stops faster. This is still a big market to sell into.<br>

I think a $799 list price lens of this quality will sell well in this market. What is a <br>

24-70 f2.8 selling for? $1,888.00. Sure you can buy a third party 24-70mm, but<br>

looking at the lens reviews its not as good as this lens' reviews and the buyer<br>

would have to purchase a new FX body to use it. That is enough reason to<br>

just buy the new lens and use a camera your basically familiar with its interface<br>

and get better performance for a few more years until these FX cameras go<br>

down in price further. This lens is not aimed at pros like Shun, but I bet a lot<br>

of pros will use it for weddings and landscapes.</p>

<p>I think Sigma prices the 18-35mm/f1.8 to $800, which is quite low for such a fast zoom, because they realize that it will be a touch sell. If it were like $1200 or so, they would hardly sell any. If it is indeed the case that some small camera store already has a long pre-order list, that means Sigma prices it very wrong.</p>

<p>Recall that a year ago, there was a long waiting list for the D800 and D800E. Since it was "free" to pre-order, people just got onto many waiting lists from B&H, Adorama, Amazon .... They would just take whatever one that came first and cancelled the rest; it was quite chaotic. I ordered my D800E from my local store only, around April 18 and they delivered it just before mid June, so it was almost a 2-month wait. If this Sigma 18-35 were the hottest-selling item in decades, it sounds like some store may have missed the introduction of the D800 as well as many other items. Likewise, IMO Nikon probably should have set the D800 to around $3500 (like the 5D Mark III) instead of $3000 and then lower it after, say, 6 months. Nikon would have made more money and we would have avoided such chaos.</p>

<p>Nikon has already phased out the entire high-end DX DSLR category. I wouldn't expect them to update the 17-55mm/f2.8 DX AF-S either. Their emphasis is now the lower-end FX. Not that the Mutli-CAM 4800 is bad, but I would like to see them update the D600 to a better AF module to have more AF points covering the FX frame.</p>

<p>My 'local' does not do internet sales ... I suppose they would, but they certainly don't encourage it. Just left there to leave MORE material from a busy weekend ... talked about it some more with them. "I think we are a disgrace to capitalism in some ways ... we don't want to be big...we do however want to be excellent", they say, (my experience, ARE). Henry Posner (B&H) posted a piece on DPR awhile back for folks who pre-order everywhere, and take what comes first, and <em>sometimes</em> cancel the multiple pre-orders they have made. Others order, say, a D600, a D800, and a D800E ... get all three, fool with them for a few days to see which one they like best, and send the others back. Still others order something, don't read the manual ... get confused, and or po'd, because it doesn't 'work right' and send the goods back. My local has no shipping department, per se, and certainly does not want the sales staff fooling about with packing peanuts and cardboard boxes. I also must add ... 'Sigma prices it very wrong...' Remembering last year, and always, actually, lots of folks pining away for a, perhaps $100 discount on a piece of equipment in the 1500-2000 range ... 'Should I order now, or wait for a possible holiday rebate?', they asked. PRICED TOO LOW ... maybe it's a new marketing strategy ... looks like it will be a 10 pointer quality wise ... everyone expecting $1200 or so ... the strategy? Perhaps they plan to loose a little on EVERY SALE, and <strong>make it up in</strong> <strong>volume</strong>...they obviously have their corporate head screwed on a little different than the 'majors.' Got no plans to sell my 17-55/2.8 ... excellent in every way, no complaints. But I WILL buy the Sigma after the first of the year ... my wife's chagrin at 'doubling-down', not withstanding. Also, the store corrected itself ... two other occasions of interest HUGE ... one in '64 when they hired a Marilyn Monroe 'look-alike' (a dead ringer for MM), you could come in, in a set-up studio setting, and take her picture ... free... (place was mobbed), and another, when Neil Armstrong landed on the Moon, July 20, 1969, with The Moon Camera ... a Hasselblad 500EL ... local store had Hasse, both the 500C and the EL in stock ... when the crowd found out how much it was ... they mostly (not all) kinda faded. God save us from pricing too low.</p>

<p>OOPS ... a little vexed at 'priced wrongly' or (implied) priced 'too low'. Should read "God save us from pricing too low, NOT".</p>

<p>On pricing, I did find it interesting that Nikon seem to be under-cutting the Canon equivalent models in FX (still true of the D800 vs 5D3 and D4 vs 1Dx in the US; true of the D600 vs 6D as well in the UK). I can understand a price war, but there's always the problem that a higher price makes people wonder if there's a reason for the premium. I tend to look at the additional price of a 5D3 and think "enough people must think this camera is better than the D800 that Canon can charge more for it" - whereas admittedly with the D600 vs 6D I tend to think "Nikon can make this for less than Canon can and they're price gouging each other".<br />

<br />

Honestly, I <i>do</i> think the 5D3 is better for more people than the D800 is (which doesn't stop my D800 being better for <i>me</i>), but I have a low opinion of the average consumer and expect more people to go "ooh, megapickles" rather than "actually I'd like a better autofocus system and an extra 2fps", so I'd have expected Nikon to try to wring profits from people more. I guess they're really going for market share, but if the "cheaper means worse" perception is true, they're doing themselves a disservice with the current pricing structure.<br />

<br />

My point being that Sigma might have the some problem. People think twice about buying, say, a 100mm Tokina macro lens when the Nikkor is twice the price, irrespective of whether the Nikkor is actually better. Zeiss benefit somewhat from this in reverse (some of their glass is epic, some is actually about the same as the Nikkors). You may sell more lenses at a cut price, but you might always lose sales from people who pay the premium "just to have the best".<br />

<br />

But it's all a game theory marketing problem, and I'm sure people who are far more aware of the principles than I am have worked it all out. At least Sigma weren't afraid of charging for their 50mm f/1.4.</p>

<blockquote>

<p>For the fastest zoom available it breaks new ground, but the numbers put this on par<br /> with fixed fast primes, and that is really a DX game changer.</p>

</blockquote>

<p>that is precisely the thing, here.</p>

<blockquote>

<p>if I want f1.8 for low-light work, I would use FX</p>

</blockquote>

<p>well, since there aren't any other 1.8 zooms, that would mean copping the 24/1.4, 28/1.8, and a 35/1.4, as well as an FX camera. there are no 18 or 20mm 1.8 lenses, except for the film-era sigma 20/1.8, so you wouldn't be able to duplicate the entire range, plus you'd have to pay upwards of $3500 for those three primes new.</p>

<blockquote>

<p>I think this lens will be a tough sell</p>

</blockquote>

<p>how,? why? this seems like backwards logic, since there have been far more DX DSLRs sold than FX. let's say i'm a DX camera owner. i can get a refurb d600 right now for $1600, but then i'd have to also plunk down serious cash for a 24-70, and likely replace other lenses too, and i'd gain... what? one stop of hi-ISO vs. a d7100 with an 18-35? in other words, the FX DSLR would only be an asset at above ISO 3200, however with an 18-35, i could keep my ISO at 3200, because of the ability with the 18-35 to shoot at sub-2.8 apertures (with what looks like critical sharpness). Shooting low-light as often as i do, i can tell you that aperture trumps ISO, since often you have varying light levels (in a concert/club environment). if you have a bright light source within the frame, but the rest of the scene is not so well lit, shooting at hi-ISO can cause overexposure. OTOH, opening up the aperture, you don't have the same problem.</p>

<p>IMO, Shun is just being skeptical here for the sake of skepticism, but that skepticism also maybe speaks to the fact that people have to wrap their heads around innovation, especially once they get used to the mundane. A game-changer is called a game-changer for a reason.</p>

<blockquote>

<p>Nikon has already phased out the entire high-end DX DSLR category.</p>

</blockquote>

<p>We don't know that for sure, but even if that were the case, they haven't eliminated the need for such bodies, especially since they built those expectations up with the d300. I'm a d300s user, and not only does my camera continue to see use, but one of the big reasons i haven't gravitated to the d7000 or d7100 is they dont have all the pro features i need for shooting events and have become accustomed to. I know i'm not the only one in this boat; there have been many threads in the past couple months on this topic. And, i've said this before, but IMO the only fault in the d300/d300s is the hi-ISO performance. The 18-35 mitigates this.</p>

<blockquote>

<p>Not that the Mutli-CAM 4800 is bad, but I would like to see them update the D600 to a better AF module to have more AF points covering the FX frame.</p>

</blockquote>

<p>and there you have it: the lack of a top-end AF module is one of the things which has kept me away from a d600, which otherwise i would consider. but in terms of image quality, i dont think FX necessarily has a big advantage over DX, especially if you're using good lenses. the main advantage these days is really hi-ISO performance, which, again, the 18-35 sigma mitigates.</p>

<blockquote>

<p>f/1.8 is nice, but it's not like there aren't f/1.4 primes</p>

</blockquote>

<p>oh yeah? show me a an 18mm or 20mm 1.4 prime, if you will. i'll be waiting... as i noted earlier, you can't get a good 1.8 prime in the 18 and 20 focal lengths. the 24/1.4 is $2000, or more than double the price of the 18-35, and obviously a fixed-focal is a lot less versatile than a zoom which covers 5 prime ranges (18/20/24/28/35). But we are not merely talking about versatility and convenience here, but performance which appears to be as good as it gets in zoomland--similar to how the 14-24 made all the other primes within its range obsolete.</p>

<p>F1.8 to f2.8 is about twice speed gain as f1.4 to f1.8. So if 1.8 doesn't blow away your<br>

17-55mm f2.8 then carrying several prime lenses just to go from f1.8 to f1.4 is something<br>

you are most welcome to pack on vacation, hikes, etc. For me a 27-53mm range on DX<br>

is useful. Many WA shots can be handled in that range, street , group portrait, and<br>

interiors in available light can usually be handled too. With a D7000 , D5200 and D7100<br>

High ISO is clean enough to get useful shots at ISO 3200 with f2.8 , with this lens<br>

you can get the same shot in 1.25 f stops less light, meaning you can reduce that ISO<br>

or raise the shutter speed. Ilkka makes a good point about many people who don't<br>

ever use external flash, only the pop up flash. Many will get this lens, maybe on a Christmas<br>

rebate sale.<br>

I hope someone from Adorama or B&H can settle this by telling us how well the pre-orders<br>

are going. There are 5 more weeks before the product is supposed to start shipping<br>

to pre-orders, in two weeks I bet the first wave of allocations is sold out.<br>

Bruce, I think your local camera store is indeed a good random sample, because<br>

people who don't multiple order via the internet didn't walk in the shop, real people<br>

drove down to a shop, looked the salesman in the eye and said "I want this lens"</p>

<p>on a personal tip, a game-changing DX zoom lens with incredible sharpness at sub-2.8 apertures for $800 was the last thing i needed right now. i'm still considering the sigma 35/1.4 (for my FX camera) and the Fuji X100s, dammit! if the cost was $1000+, i could say "nah, too rich for my blood," and pass. but at that price, i might just have to check it out. not sure how i'm going to afford it as well as the other goodies i want--note to self: <em>get more paid work at higher prices!</em>--but i think Sigma was smart to set such a reasonable price point, considering the glut of options which are oversaturating the imaging market right now. it's a revolutionary idea to price a product at a point which is exactly what it should cost, as opposed to making it overpriced because of the idea of cachet. if this lens does sell in high numbers, it could be a wake-up call to Canikon to treat their consumer base better.</p>

<blockquote>

<p>well, since there aren't any other 1.8 zooms, that would mean copping the 24/1.4, 28/1.8, and a 35/1.4, as well as an FX camera. there are no 18 or 20mm 1.8 lenses, except for the film-era sigma 20/1.8, so you wouldn't be able to duplicate the entire range, plus you'd have to pay upwards of $3500 for those three primes new.</p>

</blockquote>

<p>Eric, you are completely missing the point. DX needs larger apertures because they have worse high-ISO capability.</p>

<p>Currently, FX has about a 1.5-stop advantage over DX as far as high-ISO capability goes, based on my observation since I have a D800E and a D7100. Therefore, an f2.8 zoom on FX will give you about the same high-ISO results as an f1.8 zoom on DX. Meanwhile, a 24-70mm/f2.8 on FX will give you a very convenient zoom range, compare to 18-35 on DX, which is the equivalent of 27-53mm on FX, a very awkward zoom range.</p>

<p>Therefore, I don't even care how good a 18-35mm/f1.8 DX lens may be optically, it is certainly not the same event, indoor lens a 24-70mm/f2.8 is on FX.</p>

<p><br>

</p>

<p >I looked at upgrading to FX a while back. But I struggled that with the same final image there might not be a significant difference in the majority of my photos for me to justify the upgrade costs. By the same final image I mean matching the field of view, visual depth of field and sensor noise in the picture.</p>

<p > </p>

<p >You have to move a stop on the FF to get the matching DX visual depth of field so you have to run at a higher ISO to compensate. So the “1 stop” advantage of the FF has just been lost to make the prints look the same as a DX.</p>

<p > </p>

<p >The advantage comes when you use the narrowest DoF. With FF it’s easier to go “1 stop shallower” in the final print.</p>

<p > </p>

<p >So with FF you can get a shallower depth of field in the final image compared to a DX image and so with it the advantages that gives. Less noise as you lower the ISO back a stop (or more artistic DoF effects? could be seen as good or bad depending on subject!).</p>

<p > </p>

<p >So if a difference of 15 in a DxO score equals 1 stop would a 24MP D7100 (DxO score of 83) with the Sigma 1.8 produce a better print in low light conditions than a 24MP D600 (DxO score of 94) with a 2.8?</p>

<p > </p>

<p >Based on approximate recent street prices:</p>

<p > </p>

<p >£1600 (£900 + £750 (estimate!)) DX kit</p>

<p > </p>

<p >vs</p>

<p > </p>

<p >£1950 (£1350+£600) with a Sigma 24-70 to</p>

<p >£2600 (£1350 + £1250) with the Nikon 24-70 FX kit.</p>

<p > </p>

<p >Is it worth £350-£1000 extra cost, a lesser focus module and more weight just for more zoom range?</p>

<p > </p>

<p >So it comes to the personal choices of what lenses (quality, cost, size, weight) and camera (body quality, size, weight, focus module, FPS, viewfinder) and convenience (zoom range) you want and looking at the price for the system to upgrade or change from where you are.</p>

<p > </p>

<p >Yes a 3x zoom is more useful but I think currently it will cost you for that. But then again you could add a 50mm 1.8 to your DX system to make up for that. But that is adding another £150 and the inconvenience of swapping lenses.</p>

<p > </p>

<p >And on the workarounds and compromises go to build your system…</p>

<p > </p>

<p >But many with a DX system may find trying the Sigma 1.8 2x zoom a reasonable upgrade to their existing camera kit for the $799 verses switching to a FF system and a 2.8 3x zoom.</p><div></div>

<p>I understand why we talk about how good a lens is or how bad it is. I am not sure why we care about how many lenses Sigma will sell. How is that relevant to someone who is considering buying one? In any case, in that regard Sigma has an advantage over Nikon or Canon since they sell to both platforms.</p>