How do I check softness....

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I would like to test a few of my lenses for softness and focussing problems, could anyone offer any advise of setups I could use and camera settings etc.

My main concern is my 100-400 which seems quite soft at times, id also like to test it with the 1.4x to see any quality loss.
 
If you do a search, I think Sammy C posted a link a while ago.
 
Are you sure your looking for softness in the lens?

Could quite easily be shake ......i'm a master at soft images through the art of camera shake.
 
Thats exactly my problem, I dont know if its me or the camera/lens combination, at the moment im struggling to get any really sharp images out of the 1dmkII w/100-400 whereas last year using my 20D w/100-400 I seemed to have more success. :crying: I need a way to check the lens taking me out of the equation, my tripod is very poor, Star63 iirc.

Some 100% crops dont understand the colur differance, no changes made in RSP.

100-400@400 (f22 2.5s ISO 200)
Center
KX7G1669.jpg

Corner
KX7G1669-02.jpg


100-400 +1.4x @350 (f18 1.3s ISO 200)
Center
KX7G1679-02.jpg

Corner
KX7G1679.jpg
 
DreederUK said:
100-400@400 (f22 2.5s ISO 200)
Could be completely wrong, but I thought most lenses were sharpest around f/8... why are you testing at f/22 ?.
 
with the 1.4x on F8 is the max aperture, i went for about the middle of the range tbh.. But if f8 would be optimum i will retake at that setting tomorrow, its that kind of stuff that im asking for really recommended settings and setups.
 
I'd start by taking off the TC and setting the camera to the lowest ISO

No point adding extra variables into this. Also am I right in thinking that your autofocus won't be working if f8 is the widest aperture?
Might well be a compatability issue between the Mk1 eyeball and the camera.

I'd also not be using a shutter speed of 2.5secs unless I knew my tripod was solid.

If you have support issues mount the camera on a table and use the selt timer.
 
Ok cheers, I will try and take some shots outside if the weather gets better, without the TC, ISO100, F8.0 and as fast shutter as possible.
 
Also, if your camera has the facility, use mirror lock up to cut down on vibration when taking test shots, at 400mm it won't take much vibration to ruin an image.
 
If you can get more light on the subject it might help - bung a flash on there.
Edge resolution on most lenses is pretty poor (compared to the centre) at anything other than f/5.6-8.
Unless you're doing a lot of copy work it shouldn't really matter unless it's noticably bad.
Occasional rogue lenses do slip through the QC depts sometimes, but in my experience it's usually down to operator malfunction - camera shake! We all do it...
 
digitalfailure said:
Also am I right in thinking that your autofocus won't be working if f8 is the widest aperture?

Canon 1 series cameras can auto focus up to F8.
 
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