How to test your lenses for sharpness?

take pictures!


seriously there are test charts and stuff - but unless you think you have a serious problem - why bother - life's too short - just take pictures.

let's see some you're not happy with.
 
Simply go out and use it. There's nothing like testing in the real world. More fun than shooting newspapers and rulers, too.
 
Taking normal pictures to test the lens is the best way. Taking images of test charts and newspapers are all well and good and cause a lot of concern until you understand that few lenses are flat-field and therefore there will always be descrepencies across the image.

If the lens appears not to be focussing correctly, then that is a different matter and will need to be resolved (pun intended) buy micro adjustment (if available) or recalibration by the manufacturer.
 
Yeah i get this but i keep reading on hear about(Sharp Copy) i am asking as it is said about one i have(Sigma 70-200mm f2.8) so i thought maybe there was a way you could test this.

And ok take pictures and then what? I'm asking so i can check for myself.
 
What i mean is should i be setting my camera in a way that will give me the sharpest image to see if it's soft?
 
Anything with fine detail in, which is pretty much anything really.

Birds are always a good test.

edit, turn it to program mode and take a picture...
 
Best thing, IMO, is to use the lens as you normally would and see how the pictures turn out.
 
It's virtually impossible to tell with such small pictures (which are very nice BTW) but I would say that they appear to be in focus (except the hamster shot has focused on the cake, not the critter) and have picked up some fine detail.

What camera and lenses are you using?
 
Shooting test pictures of flat targets is dangerous, as Ed says. It will often make you think your lens of out even when it's not.

If you want to see if you've got a 'good copy' or not, shoot a distant target (to minimise focusing errors) like a road sign or number plate. Lock exposure on manual and take four shots with the target in each corner of the frame - do it quickly, in case the light changes which ruins everything. Shoot at lowest f/number and highest shutter speed you reasonably can get. Enlarge the target area and compare the four images - they should all look the same. If one or more is noticeably worse than the others, chances are the lens is not properly centred which, nine times out of ten, is the bad copy problem, or a sign that the lens has been dropped. Don't expect stuning quality as you probably won't get it - it's a tough test. You are looking for equality not perfection.

If you want to know if the lens is generally good quality, the only way to do that is side by side testing against another lens of known high quality (Nikon or Canon) and shoot identical comparison shots.
 
Most of them where taken with a 30d and a 70-200 f2.8 and maybe a 28-80 canon lens(which i think is mince).
 
You need to post them here at 800px longest side - and leave the EXIF intact so we can see what you're doing.
 
GlasgowGunner said:
It just seems that nothing seems to look sharp no matter what lens i use.
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So it's unlikely to be the lens :)

Don't forget ALL images shot in RAW will require sharpening in PP can you tell us what you shoot in and how you process?
 
The manufacturers have done all that tedious testing beforehand so that you, the consumer, can go out and take photos without having to worry that your lens is sharp enough to out-perform the resolution capabilities of the film or sensor you're using to record the image.
 
are these hand held or on a tripod? 2nd shot - EXIF shows 200mm lens shutter speed 1/20th of a second!
 
They don't look all that sharp - did you use a cable release to fire the shutter? Were they shot as RAW or joeg - have you done any processing before posting?
 
awp said:
They don't look all that sharp - did you use a cable release to fire the shutter? Were they shot as RAW or joeg - have you done any processing before posting?
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cable release, no.
jpeg and no processing.

I dont feel im getting a sharp shot from any lens i use.
 
The snowman looks fine to me, but those long-lens shots are very soft...

20th sec on a long-lens, whether on a tripod or not needs to be rock-steady - mirror locked-up etc just to be on the safe side...

Try another test using a faster shutter speed - what I'm looking at there looks like camera shake and maybe a bit of pre-process RAW softness if they were shot that way.
 
Arkady said:
The snowman looks fine to me, but those long-lens shots are very soft...

20th sec on a long-lens, whether on a tripod or not needs to be rock-steady - mirror locked-up etc just to be on the safe side...

Try another test using a faster shutter speed - what I'm looking at there looks like camera shake and maybe a bit of pre-process RAW softness if they were shot that way.
Click to expand...

Im going to take a walk down the canal soon and test this out, im right in saying at 70mm shutter speed should be about 140 and at the 200mm end 400,,,Yes.

Love your Army shots by the way very, very impressed with them i have to take my hat off to you guys.

Did i read about you in a mag a while ago?
 
As a rough rule 200mm lens needs a 200th sec - and as said above 1/20th even on a tripod is not enough unless you lock up the mirrot and use a cable release. If you can't get the shutter speed up you need to increase the ISO. You also need to give a little sharpening in PP.

I think what he means is your problem has a lot less to do with the lens and more to do with user error!!
 
GlasgowGunner said:
Im going to take a walk down the canal soon and test this out, im right in saying at 70mm shutter speed should be about 140 and at the 200mm end 400,,,Yes.

Love your Army shots by the way very, very impressed with them i have to take my hat off to you guys.

Did i read about you in a mag a while ago?
Click to expand...

No - 60th or faster at 70mm should be OK and 200th-250th or faster at 200mm...
Broad rule of thumb is a reciprocal shutter speed to the focal length if hand-held...
On a tripod, as long as it's really clamped down then you can leave the shutter open for days if you feel like putting 50 ND filters in front of the lens...

And no...it was the fat one you read about...the Lardy Git...he wrote that himself you know, shameless exhibitionist that he is...lol
 
Arkady said:
No - 60th or faster at 70mm should be OK and 200th-250th or faster at 200mm...
Broad rule of thumb is a reciprocal shutter speed to the focal length if hand-held...
On a tripod, as long as it's really clamped down then you can leave the shutter open for days if you feel like putting 50 ND filters in front of the lens...

And no...it was the fat one you read about...the Lardy Git...he wrote that himself you know, shameless exhibitionist that he is...lol
Click to expand...

Hmmm, i read about this person in Digital Photography i think?
 
awp said:
As a rough rule 200mm lens needs a 200th sec - and as said above 1/20th even on a tripod is not enough unless you lock up the mirrot and use a cable release. If you can't get the shutter speed up you need to increase the ISO. You also need to give a little sharpening in PP.

I think what he means is your problem has a lot less to do with the lens and more to do with user error!!
Click to expand...

You also need to give a little sharpening in PP.?????
 
all digital images need to be sharpened a little in post processing - in PhotoShop in your case.
 
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