Posted by chris jones on December 12, 2009 at 9:49 AM
hi
working from all the advice from the great people on here i have re done the test of my lens,i will try to be as short as possable and give you all the info you need to give me the advice i need as to the lens been a good or bad copy.
test info
tripod used- ball head (is )turned off
shutter speed -500 of a second
apeture - 5.6
focus - centre focus spot only
servo - one shot
mirror lock up - on
object used - money note to give good contrast
shutter triger _ 10 sec self timer
camera used 1dmk2
hope all this info can help you to give me a informed decision
on the lens .
link to sammple pics ( 100% CROPS )
http://www.flickr.com/photos/csjones/sets/72157622985528584/show/
please copy and paste above link
Posted by Andy Astbury on December 12, 2009 at 10:28 AM
Chris - what am I looking at?
You need to quantify what the differences are between the images - such as focal length, aperture etc for this to mean anything.
What you should do is show a set of sequences at 100mm f3.5 to f22, 200mm f3.5 to f22, 300mm f5.6 to f22 and 400mm f5.6 to f22.
And don't crop any of them.
Posted by chris jones on December 12, 2009 at 11:00 AM
all the images are at 400 mm where the lens is giving me soft imagies wide open at the apeture i would like to use for my bird photos . the problem is with no diffrence in taken one pic from another like in this test how can a lens give such varable results, the pics are 100% crops because if the image is not sharp enough for me at 100% the lens is no good to me.
Posted by Andy Astbury on December 12, 2009 at 3:18 PM
If you are telling me that every one of those images is 400mm @ f5.6 then I can see where you are coming from.
However, some of them are sharp so guess what - the lens is sharp.
Focus errors are usually caused by the AF unit in the camera - and most commonly this down to AF setup.
It's a funny old lens.
Sometimes it's bitingly sharp and capable of resolving excellent detail, other times, the quality just isn't there for no apparant reason.
I can't explain why this is the case, it just is, at least in my experience with the lens.
Posted by Phil Shaw on December 13, 2009 at 5:48 AM
Clearly the lens is capable of delivering sharp images, so it is unlikely that there is anything wrong with it. What your testing is showing is the limitations of the AF system in the camera as influenced by the maximum aperture of lens (f5.6) and the number of lens elements in the zoom.
For the type of photography your are intending, the 400/f5.6 prime has a reputation for delivering consistently sharper images at f5.6 than the 100-400.
Posted by Tracy Hope on December 13, 2009 at 1:59 PM
I have had the same kind of issues with my 100-400. I am using a 50D and I have found if the day is sunny (lots of contrast) it works wonderful. When it is later in the day or on a very cloudy day it isn't so good in that the photos seem soft. I also have found that shooting wide open at 400mm seems to get me soft shots, but if I go up a stop or two it gets much sharper.
Discussion
6 repliesworking from all the advice from the great people on here i have re done the test of my lens,i will try to be as short as possable and give you all the info you need to give me the advice i need as to the lens been a good or bad copy.
test info
tripod used- ball head (is )turned off
shutter speed -500 of a second
apeture - 5.6
focus - centre focus spot only
servo - one shot
mirror lock up - on
object used - money note to give good contrast
shutter triger _ 10 sec self timer
camera used 1dmk2
hope all this info can help you to give me a informed decision
on the lens .
link to sammple pics ( 100% CROPS )
http://www.flickr.com/photos/csjones/sets/72157622985528584/show/
please copy and paste above link
You need to quantify what the differences are between the images - such as focal length, aperture etc for this to mean anything.
What you should do is show a set of sequences at 100mm f3.5 to f22, 200mm f3.5 to f22, 300mm f5.6 to f22 and 400mm f5.6 to f22.
And don't crop any of them.
However, some of them are sharp so guess what - the lens is sharp.
Focus errors are usually caused by the AF unit in the camera - and most commonly this down to AF setup.
Sometimes it's bitingly sharp and capable of resolving excellent detail, other times, the quality just isn't there for no apparant reason.
I can't explain why this is the case, it just is, at least in my experience with the lens.
For the type of photography your are intending, the 400/f5.6 prime has a reputation for delivering consistently sharper images at f5.6 than the 100-400.