Discreet said:
Question to Snow Eagle:
1) Tripod mounted? I am assuming you are using MLU and a release cord.
2) Why shoot in AV? Should you not shoot in M and keep everything constant?
3) Why just at F8? You should have shoot at least wide open to compare? Most of your lens can reach F2.8 or F4. People just dont shoot at F8 all the time
4) What are you shooting to compare the corners?
5) Are you focusing objects that are close or far away?
6) What were the lighting conditions? Indoor Outdoor?
7) Did you use AF? Are you sure that your focus was dead on? Maybe your camera AF was out of range?
8) Define what sharp means to you?
9) Did you shoot jpeg or raw? What were your shooting parameters?
10) Did you just use one lens for each test? There are sample variations and you might get a bad copy?
11) What body did you use? You have a EOS30QD on your signature. Are you using film? What film were you using?
12) If you were using a digital body, what was the crop factor? Are you comparing FF? or 1.6x or 1.5x?
13) Were you using a filter when you shot with these lens?
14) When you say that a lens is good throught out its range? What kind of range are you talking about?
15) to compare the lens, are you zooming in and out or are you moving the tripod in and out to get the same picture? or do you compare different FOV
16) Correct me if i am wrong but if it appears you tested these lens at different occasions and what steps were taken to ensure that the test were consistent?
I am not trying to be hard here or make anyone look stupid but all i am trying to do is to show you that testing lens is not a simple thing. There are tons of factors that go in testing a lens. Every test or review has its flaws and loophole and the only thing we can do when we intepret it is to take it with a pinch of salt. I am sure Snoweagle is very confident of his results and I am in no position to question the results of his testings because his measure of how a lens should performed and hence the test method is up to him.
All I am saying is that as a newbie or anyone is looking at these test is to understand that ultimately the result is someone's else opinion and not the cold hard truth. Do yourself a favor, and try to borrow or try out one of these lenses for a while (not just 5 mins but for a extended shooting session if possible). The general rule is that you pay what you get for, so dont expect the kit lens to perform like an L. Also, sharpness and color is one thing, but personally, the most important thing is the focal length. What is the use of having the sharpest and most contrasty lens if the focal length does not work for you.
Cheers
If usually a person buys a lens, there's no need for such extent, but since u asked, i'll honour yr questions.
1) Yes i'm using a cable release.
2) Av as not all pics are shot at the same place so lighting differs and so do shutter speeds to get exposures well exposed.
3) f/8 as usually lens are sharpest withim f/8 to f/11.
4) Shooting basically people and just the everyday things we see around us. This is just a test.
5) Focusing distance are usually within a few metres away from where i stand.
6) Conditions are all indoors with flourescent lightings.
7) My AF always locks before i shoot.
8) Sharp is having no 'blurness' or any out-of-focus cropped at 100%.
9) I don't use digital for these.
10) Nope, some are used for the same tests.
11) I'm using Fujifilm Superia Xtra 400.
12) U should know.
13) All lens are without filter.
14) Range as in the whole zoom range.
15) As decribed earlier on, not all lens are tested at the same place.
16) U're right. As mentioned in my previous post to sehsuan, i used f/8 with a tripod for all tests. I'm just testing sharpness and colour, not too in-depth into it.
Hope i've answered yr doubts.