neil_fiertel

<p>I was considering buying the Sigma 120-400 lens and read the amateur user responses and blogs regarding this lens and they were all over the map. I was suspicious but not at the lens but rather at the letters and blogs. I bought one on the proviso that I could return it if I was not satisfied. My first attempts at testing my lens in real use conditions were not too good. I realised that on a tripod one had to shut off the image stabilising funciton for one thing. I noted that a number of the letters I had read did not mention having done this. I also found that shooting on a tripod with this very big lens with a full frame Canon resulted in tripod shake sufficient that when really critically testing this lens for what is its best quality proved to me that the lens was fine but that most of the time, it is camera/mirror shake and not the lens that is the culprit. Yes, I was using either timer or remote release. In the end, I found that I could stabilise the tripod with weight and the lens was fine and dandy. I wanted to use it portably and I solved that well also. I built for this lens a grip so that I could hand hold it with image stabilisation and can capably take long distance shots at 1/25th of a second and print such images over 3 foot print sizes consistently. What it shows is that it is often about technique and knowledge and that the inconsistency of the optics might very well have more to do with the user than the company that makes the lenses. Sure, sometimes a lens is a dud. Many of my old fiim lenses were very inferior to the present optics common today and thus I have my doubts that there is some sort of fall down on the optical side of technology today. To the contrary. It is a fall down on the user who does not really know the photographic skills that old fllm users HAD to know in order to get any decent result what with slow shutters, less than sharp lenses and available lighting conditions with slow or grainy film stock. What I suggest for those that have what they feel is a bad lens...consider a serious and properly controlled test rather than running off at the mouth about how bad this or that lens is. Rather, one might want to think..it is I and not IT that is the problem. </p>

<p>I just repaired, for nothing, an ancient Star D Continental tripod. It did not rotational lock nor did the centre vertical shaft lock. I took the whole thing into pieces, adjusted each of the hidden parts for the legs so that they would have just the right amount of tension and not mash fingers when the as before swung fairly loosely and slipped in a piece of mylar into the locking mechanism as the plastic sleeve within the tensioner was no longer the right thickness after a long period of use. With some adjustments of the tensioner on this wonderfully considered tripod design it is very usable if not as smooth on the centre shaft as one would like in the ideal world but the money saved on this very sturdy and super steady tripod can be a good down payment on an L lens. Not any heavier than the high tech tripods out there which I would not suggest one can repair on one's own, a Star D is a gem. I use a Slik head screwed onto the pan tilt that is a part of the Star D and seems not to be removable without risk to the column. I understand that one can replace the centre column with other brands and I might look into doing that. In any case, the tripod works a treat and holds steady even with my very hefty 5D mk II and a 120-400 zoom lens. One need not spend a fortune for steady tripods..look for them in used camera stores or on line. They are out there. 700 bucks for carbon fibre tripods? You have to be rich and foolish I think. I am neither.</p>

<p>This is a very fine lens in fact. I kept my 40D even after upgrading to a 5D mk 2 just because of this lens and the compromise of using a smaller sensor camera is compensated for the optical precision of my particular 10-22 mm optic. Your reasons might vary from mine as to why I like this lens but it is not a cheapo optic in the least even if it does not have an L designation. The proof of the pudding is always in the photographic results. I like the fact that I can produce eccentric very exaggerated affects with this lens by shooting from odd angles and close to the subject which many lenses cannot duplicate. That alone is a good reason for me to keep it and the associated camera. I do not work in dusty conditions so the fact that the lens is not sealed is not a downside to me. Too bad, really, that I had invested in HFS lenses in the first place as selling them was financially painful. This one is going to stay with me with the decent 40D. In all truth, 90% of camera users would never see the difference between an APS sized sensor and the full frame. Since I happen to standardise my image prints at 24 by 36, one can see differences there all right but with judicious sharpening and other manipulations which one can make ( and believe me, realism is not my interrest at all ) one can make prints of that size even with an 8 megapixel compact camera such as the G9 given good lighting conditions and a low ISO setting. Thus, the 10-22 lens on a APS-C sensor allows pretty much the same kind of quality that I expect from my wonderful 5D mk 2 much of the time. After all the idea of using a WA lens is to use the entire frame for its open view of the world. Cropping is counter productive and thus a full frame of an APS image is quite wonderful if shot with a low ISO setting which is inevitably my goal in order to achieve quiet and sharp imagery. It is a good pairing of optics and camera.</p><div></div>

Normally am not a gambler but it was a no-brainer to try the Sigma 120-400 zoom as my dealer said I could return it if not satisfied and it is just over half the price of the Canon 100-400. That being said I could not tolerate the Canon push and pull system.I used it also as a friend owns one and frankly, I hate it. I am not a sports photographer where I suspect it has its uses but if one is composing that is the worst way to have to deal with subtle adjustments. The Sigma on the other hand is the standard rotating zoom and focus rings and it works a treat. The construction is fantastic with no wobble whatsoever and the focus is very smooth and short from infinity to about 5 feet or less. The zoom is stiff but fine and I suspect that will loosen up over time. Now to the real issue..image quality. I used it with a 21 megapixel Canon 5DMk 2 so I can really tell you that the lens is amazingly good. Wide open at 400mm there is a slight roll off on resolution in the extreme corners but at f8 it is sharp right across the file. I work with image that are generally 36 inches and this lens produced snappy and sharp images with fine contrast and lovely bokeh. In  backlighted situations there is a little flare but this is just the way zoom lenses are what with so many elements but under more reasonably conditions this is not an issue. In fact, the flare is well controlled and can add a pleasant aspect ot the image if one is not a nut case about everything being just perfectly perfect. The lens at all zoom ranges was exemplary and as long as one stops down a stop the image quality hardly varies at all.There is no discernable pincushion or barrel distortion.  I actually set up a geometric flat object to make certain and it was wonderful. Interestingly, the old test of flatness of field so seldom done nowadays showed that the lens had amazingly good flatness of field and thus was in focus at the same time in the centre and the corners. It is a winner. With regards to OS or image stabilisation I consistently could hold this lens at 1/20 of a second shooting at 400mm and get perfectly sharp 36 inch prints with it. I did not believe it the first few times so I went outside and photographed a branch against the sky at infinity distance and all were as described..right on the money. I have read how some complained the lens did not focus rapidly. On the 5D MK2 focus was nearly instantaneous so long as the lens was in the general ball park of focus. It was nonetheless extremely fast going from inifinity to close up in any case. I think therefore that it is also about the camera lens combination rather than that the lens is inherently slow or fast at the AF. My experience is terrific in other words. The OS is quirky to be sure. One hears it and the image jerks as if having a short convulsion but it is one lurch and then it is uncannily LOCKED onto the image which is most intriguing. One surely knows that it is stabilised. The tripod mount is finger grooved but I haver large fingers so it is a tight squeeze for me and I am at the moment building a grip for it to attach under the lens as that really helps such a heavy piece of kit. I did a temp fix and proved it to myself so now I am making the effort to build a perfect grip since these seem to no longer exist on the market as they once did. I do not find that the OS runs the battery down particularly and I never change lenses with the camera on and so do not know if the warning about not doing this with OS running is really a serious threat to the lens health but I noted in another part of the same instructions a comment about a chatter sound if one removes the lens when it is running so maybe that is all that happens...I intend not to find out. Would I buy this lens again...darn straight I would. I am keeping it. It is not likely to be as sturdy over the life of its use than a Canon but Sigma comes with a ten year warrantee so who can complain about that? It is my first venture into Sigma territory by the way and I had my doubts as one can read all sorts of complaints. I feel however that many are based upon not a good understanding of camera lens practice. A long lens needs to be held rather very steadily for any decent test. I did my testing on a tripod using the timer to prevent any shake as I found at the long focal length that there was indeed shake when firing the camera with the release on a Manfrotto tripod of medium weight. It is after all a very heavy combination. It is a wonderful sharp and well designed and handsome piece of kit. Sigma should be proud of their efforts. Canon has some homework to do to beat it as in comparison, the Sigma was SHARPER at all settings than the Canon I compared it with. Your mileage may vary but that was my experience with but two lenses to compare.

<p>This is not banding..this is inherent in any ANY digital device and is the result of physics..gain in the sensor which is naturally necessary to raise the tiny voltage that results from a few photons striking the miniscule photosites. If one takes pictures with an appropriate exposure this effect is invisible. Changing the parameters by emphasizing either the gain in RAW or changing the frequency response of the sensor output by essentially tweaking the normal response of the sensor and amplification of signal is no different than turning up the treble on an audio amplifier ( remember them?) and in the latter case results in hiss from the equipment. We are dealing with physics here and the principles will never go away. Remember or learn for the first time...a CMOS or CCD sensor is an ANALOG device at the photosite. It is converted to digital signals as close to the sensor sites as possible but it starts out voltage dependent and thus there is always a noise component. What a camera company does to ameliorate such noise is unique to each manufacturer and averaging pixels is one way to deal with it as well as secret methodologies. Any digital camera that I have used will show patterning and chroma noise and that includes full frame or smaller sensors and naturaloy the smaller sensors have more noise in general OR lower resolution. Shooting pictures uisng very high ISO settings naturally are noisier unless one has noise reduction used in the exposure which does one of several things but one method is to average a black screen along with the exposure to eliminate electronic and pixel noise by subtraction ( reversing the signal and adding it to the exposed image). I produce as a standard print size..36inch prints from digital images on a daily basis..I do not have banding, I do not have noisy images after appropriate digital processing. I suggest that those that do, are not using their computer correctly in dealing with this technoloy. I have by the way made three foot prints even with the Canon G9 and believe me, I am a stickler for quality. It is all about knowing what you are doing in terms of exposure, minimal ISO, appropriate post processing and so forth. Sure, I can make that little camera show banding..I can also prevent it. On my Canon Dslrs I can also show banding but it requires more effort to ruin the image! The world of digital photography is an incredible improvement over film for me at least. Trying to get a three foot print from a 35mm medium ISO film was a miracle and rarely did it make the cut. I have a long memory for quality and today I am astounded at the quality of the best digital equipment. Surely Canon is in that rarified group of brilliant camera engineers and designers who make such state of the art cameras and lenses.</p>

When one adjust the brighness using the OSX internal calibration, there is an adjust to

match minimally seen grey tone against a black square in YOUR standard light situation.

This is correct and with my several monitors, including a 30 Cinema Display, the

brightness of the screen is correct..The issue is not the screen brightness but rather the

reality that printing is much narrow in terms of gray range than the screen..As they say,

get used to it..One has to compress slightly the dynamic range to put what is seen on

the screen on paper..It is life. I have printed somewhere over 700 prints using an Epson

2200 and I noted exactly the issue of the print being darker than the screen. I tried

pretty much everything to produce an automatic compensation and gave up entirely on

the colorsync system. I now use the color controls available with Epson and perhaps

other printers. It allows me to set a series of default settings for gamma and so forth. As

well, one can choose a different gamma on the colour calabration using the OSX colour

calibraton as well. If you get the colour right on the screen using the many colour tests

within the system preferernces monitor colour and expert mode, believe me one can get

it spot on if you have excellent colour response in your eye and brain..I do and I can as it

wre get it right and lock it in. The iMac 24 in fabulous in terms of its screen brightness

and clarity. One does not need a particular screen brightness to get it right..one needs

to have the gamma and the range within the screen calibration from black to white,

correct and consider the limited range of the paper printing process when making a file

to print.

Alien Bees are built from old fashioned heavy but well insulated bakellite, not ABS and

not any kind of thermoplastic. Bakelite does not melt in heat so it is well suited for the

use here but they can crack or break if knocked about too much. They are rough and

ready but electronically they deliver the goods at a low price. Their service is exemplary

but I suggest for Canadian customers that parts be ordered not from them but from their

Canadian parts third party company that can be found on their website. i made the

mistake of buying a new set of flash tubes from them and by the time they arrives the

shipping and brokerage fees doubled the price of the tube, Getting it from the Canadian

outfit would have saved me 70 dollars..Live and learn. The main thing though is that they

have parts and they were here in a week..good for that.