My thought on the Sigma 18-50mm F2.8 EX DC MACRO

[simdavid]

Hi all,

I have own this lens for a year on the K10D and I have nothing but full of praises for it. I find that this lens is underrated since no one really write up its virtue. Well, let me say something about it then.

First of all, the lens is focusing accurately at least 90% on the K10D, and that is already incredible and reliable. It is sharp wide open, in the center on the 50mm. It is sharp corner to corner on the 18mm wide open from what I had taken so far. I can email full res pic for those who pixel peep. I find it a very capable lens and I used it 90% of the time because it is also the most useful range for me. I can do portrait at the 50mm end and have my wide angle shots when I want it. The bokeh as shown on the flower shots, shot deliberately at F2.8 to illustrate it bokeh beauty. Compared to what I have now which is the DA50-135 and DA35 macro, I can truly say it stand on its own class and is not beaten by them. For what it is selling, it is truly a steal. I have been tempted to buy the DA*16-50 for a long time but I never found the compiling reason to say "buy it". I have also consider getting the Tamron just to fool it around but given I have the Tamron 28-75 F2.8 before, I think I will passed as well.

The lens minimum focusing distance is 30cm but I think I have push beyond that many times and thus the macro capability is indeed very useful. Do not be wishful thinking that it will give you lifesize macro but for flower shots, it is very versatile, and combined with its 7 blade aperture, you will have a nice bokeh that won't cost you an arm or leg. I have not found the CA or purple fringing annoying or even to raise an eyebrow to ask, "how can I remove that". It has never hit me as a problem but CA do exist in the picture I shot and it is just as it as, a norm in wide angle lenses and the DA*16-50 has it fill of complaint.

Sitting back in front of the lens, I asked myself, why do I like you so much. Many times, I have the urge to replace it with the DA*16-50 or even the tamron because my first portrait lens was the Tamron 28-75mm 2.8 and it made many nice memories for me too. My experience with Sigma was awful and I had the Sigma 18-125mm that time and whatever comes up from that lens went straight to the recycle bin. And before I even looked at the DA*, I could only afford the Sigma or the Tamron. Finally, I told him you win, cos you got 72mm diameter opening over the Tamron 67mm. It was a silly reason, but that reason still hold trues for me till today...lol.

Recently, I have upgraded to the K20D and the urge to get the DA*16-50 is growing stronger and stronger. Ok, I thought I should just get the DA* and give them a hard fight. It is also to extinguish the urge for the DA* once and for all but I can tell you that before even the fight begins, the Sigma has already won. Why?

1. The SDM of course, no matter how the DA* perform, once the SDM goes, I'm done for the time being and if I'm out of warranty, I still need to pat up some more money on it. So this guy can be a spoilt brat.

2. The Sigma weigh lighter then the DA*.

3. The CA on the DA* is well documented and cursed. I don't how bad is it but I cross my finger on that one.

4. The chances of getting a bad copy of the DA* has better rate of hitting 4D itself. This is one concern of mine, I can be sitting with the dud for sometime before I realise that I got a dud...lol. Though that happen to the Sigma but at least their warranty is 3 years.

5. Cost is a factor.

6. The DA* is weather seal and that completely beat the Sigma. I don't do adverse weather photography, so it's not essential but good to have.

Image quality and bokeh is my deciding criteria because I shoot alot at 50mm portrait and let's see what this 9 aperture blade can do for me. For now, if I were to have one lens, it will be this Sigma baby. Hope it helps for the next one who wants it.

Thank you

[simdavid]

[simdavid]

[simdavid]

I took the 6.30pm trip of the Farris Wheel and you can imagine how much light is left then. The street lights are already on and when I came down, it was already dark. I must say that the anti shake of the K10D plus the low ability of the Sigma helps me achieve this, I did not throw away many pics and was astonished at this combination plus how the photos turns out at the end at F2.8. It was all reasonably sharp and the K10D locked focus quickly too. It was the low light ability of this lens that I admired too.

[hamustar]

Thanks for the detailed review of the Sigma 18-50 f/2.8. It seems a like a very good upgrade for those who are feeling the limitations of the kit lens.

[epileatheral]

Sim, how much did you paid for it?

[simdavid]

For about $700.

[pinholecam]

Nice write up.

How much did you lose in terms of focal length when you moved from 28-75 to 18-50? Did you lose too much on the Tele/portrait end (esp 75mm) vs gaining on the wide end? (ie. took more WA picts that was worth losing the portraits)

I currently have the Tamron 28-75/2.8 and I'm thinking of moving over to 17-50/2.8, I certainly find I don't have enough at 28mm but my fear is the loss of the 75mm.

[simdavid]

I don't find that I am missing that 25mm lost at all because, we could just step in closer to our subject to make up for the lost of that range. Certainily, wide angle becomes critically important when we come to take landcape and the wider will be the better. In numerous situation, I have found that I can step in closer to my subject but not step out further because of obstacle or awkward situation like in a crowd. I too found the 28mm of the Tamron short on that and replaced it. The reason why this lens stay on my body 90% of the time is because I could take 18mm wide for landscape when I need too, 50mm for portrait which I do so often, Macro and product shots when I have too as well. Lastly, it is the design of this lens which impressed me that this lens is not only versatile but also produced magnificent bokeh for portrait use. It is the COMBINED traits of this lens that convinced me that she is indeed very capable. Hope that helps.

Some test shots from the K20D.

[dnaxe]

hm. you realise the 16-50 doesn't cost much more than $700 right?

[werkgg]

extensive testing for the comparison of DA* 1650 and sigma 1850 Macro can be found in <http://greenenien.blogspot.com/2007/09/da16-50mmpentax-da16-50-sigma-18-50.html>

the author also compared DA*1650 with 1645, for others considering of the upgrading...

[simdavid]

You mean not more then S$700, where to buy? $700 Sing for this lens.

[dnaxe]

No, I don't mean "not more then S$700"

I meant "not much more than (S)$700", as I wrote.

It's actually approx SGD 1112 now, including shipping/taxes.

Hm. I suppose that's possibly much more than SGD 700, depending on your perspective.

--

For someone who wanted a normal zoom lens though (pentax mount), I would say buy the Pentax 16-50 over the sigma 18-50 (for 24mm, etc.). Of course, the other obvious choice is the Tamron 17-50 (I know canon mount sells locally for SGD 650 new), and I'm not sure why the sigma would be recommended over the tamron in general - wide range tends to be better, and the tamron also tends to have a better reputation, although honestly it's probably about the same, and having a good example (as yours seems to be, going by your description alone) is excellent and is probably more important that differences in lens design.

[simdavid]

Haha, sorry I misunderstood you. Yup, It's not much more now..but factoring SDM failure, the cost would add up after the warranty period is over unless Pentax implement using the screw drive as an option. You are right, an excellent copy supercede whatever specs or lens design, a dud is a dud.

Macro shots, one at 10cm, the other at 3cm details as shown on photo.

[simdavid]

The DA*is 2mm wider over the Sigma and that is a positive attribute but because it is also wider, it has more barrel distortion on the 16mm. It is a double edge sword and it really depends on how the person is going to use it so that the distortion is not that apparent. For my type of shooting, I find that 1 or 2mm wide is negligible to me because of my own composition preference and if I really need wide, I find that I really have take two pics and stitch them up later although not very idea but doable and have done it on many occasions. But recently, I've been thinking about DA 12-24mm or the Sigma 10-20mm to go ultrawide, keena poison by this guy...lol.

http://www.kenrockwell.com/tech/how-...ide-lenses.htm






I wrote this up because I really think this lens is really capable but yet underrated. Each lens has it own strength over the competition and I merely want to provide information for people looking at this 16-50mm range that this is also an option. The first generation of this lens is really bad and soft, but this redesigned version is a wild horse run. Experience yourself and you will tell.

No matter what, if we suai suai get a dud copy, this will destroy the cabability of whatever the lens is designed to do. And finally the photos do the talking.

[otc]

I have this lens bought from OP at $650 11/2 yrs ago. Handy lens for travell and with constant f2.8 is bright enuf for most situation. 90 percent afixed to my camera when I was in Japan and Turkey.

Simdavid, tks for the comprehensive article on this lens.

marcus

[airconvent]

wow...$650 is cheap! I bought mine for almost $800 previously.
But its a great lens with very good image quality and rich colours.
Only gripe is its heavy but can't be helped if you want f/2.8 from a non-pentax lens. I find myself using primes these days so finally let it go to a forummer here. Hope he puts it to good use and post some pictures here soon!

[simdavid]

Originally Posted by otc I have this lens bought from OP at $650 11/2 yrs ago. Handy lens for travell and with constant f2.8 is bright enuf for most situation. 90 percent afixed to my camera when I was in Japan and Turkey. Simdavid, tks for the comprehensive article on this lens. marcus

You are welcome, Marcus. This lens is a Gem in hiding, so I thought to share with everyone here that this is a good upgrade after the kit. It's stays 90% on my cam too even though I have 5 others lenses to play with..lol. Glad you enjoy.

Kelvin

[simdavid]

Originally Posted by airconvent wow...$650 is cheap! I bought mine for almost $800 previously. But its a great lens with very good image quality and rich colours. Only gripe is its heavy but can't be helped if you want f/2.8 from a non-pentax lens. I find myself using primes these days so finally let it go to a forummer here. Hope he puts it to good use and post some pictures here soon!

I somehow got a feeling you will buy it back one day....lol. Just kidding.

Regards

[simdavid]

Somemore pics from this lens.