How do you test your lens sharpness?

i just take real world shots wide open. if it's usable wide open thatz fine with me. almost any lens can be killer sharp at f/8 so that's irelevant. my 2 lenses could be considered some of canon's finest, yet when used wide open they are probably softer then the new L zooms wide open. but i bought then for the extreme speed, not for the f/2.8-f/4 performance, so as long as they are easily "good enough" wide open i'm happy. i never use them at f/4 anyway. so, if a wide open large print looks great, who cares about numbers or test charts

Don't get me wrong, I like sharp pictures as much as the next guy, but I once saw a display of photographs under the title of something like 'Photographs of note' or something like that, it included shots such as the young injured Vietnamese girl running naked from a napalm explosion, several pictures of war scenes, and many others that were simply outstanding, it struck me then that probably that last thing you would think about with such photographs was 'Sharpness', what was most important, overiding all other considerations was 'Content' and, whilst I know we are not taking world shattering pictures in our everyday pursuit of our hobby or profession, that idea stuck with me and has greatly influenced my photography.

Chrisku13 wrote in post #10892898
I use a process called photography, in which I go out and test the lens in various situations and come home to see if it looks alright.

six4 wrote in post #10893075
Not a very objective method but I guess you were just trying to be funny.

...

Going out and shooting is great - but sharpness cannot be quantified or compared in situations which are not controlled.

Actually, I don't think he was trying to be funny. That is actually the preferred method for most people. Granted, you can't 'quantify' the sharpness, but I have no interest in a number, just how the images look and you can't tell that from a chart.

I am another that takes a new lens into the great wide world and take pictures that I would normally shoot. If it isn't sharp I will notice soon enough from the results.

I do see threads on here by those to whom test charts seem to be important, I guess that is a thing about such forums, they attract measurebators. In the real world, I know a lot of photographers and none of them shoot test charts, we just go out and do photography.

I have never used a test chart in my life, nor do I want to. I don't test drive a new car sat on a rolling road and look at the numbers on the dyno, I take it out and drive it on real roads.

I've also never used a test chart or even done controlled tests comparing lenses other than my Tamron 28-75, CZ 28/2.8, 17-40 shootout but they were done at f8.

I just shoot and, with the lenses I have I know what is acceptable, to me, or not. If not, the lens gets sold and replaced. Hasn't happened, yet, but could. If it seems to be misfocusing, then it gets put on a tripod and I determine if that is the case. The probelm gets resolved, one way or another.

I haven't found any reason, yet, to use test charts. I'm not sure what they would accomplish.

six4 wrote in post #10893239
well - I'd say I'm not unreasonable about it - hence why I try to have some type of objective approach to the matter.

It seems sharpness is one of the main reason why we are willing to pay more for glass therefore it is important (to me) to distinguish between glass.

Yes, sharpness is important. However, so are bokeh, colour, contrast, CA, barrel distortion, vignetting etc., most of which are either not going to show up on a test chart, or be very hard to judge how they will look in a real world situation.

I also have a 300 f/2.8L, which was mentioned above as being a ridiculously sharp lens, and I have a 100-400L which is merely 'sharp'. If I pixel peep, I can see a difference at 100% in the RAW image. Once I have done the PP and sharpened for output, then produced the final image as a print or for the web, I can't see any noticeable sharpness difference between the two. I can see differences in bokeh, in particular (the 300 kicks the 100-400s ass there) and subject separation (same again, 300 wins, due to the fast aperture) and those are far more important to me.

Yes, I can spot the difference between a soft lens and a sharp lens at final image stage, the difference between the 28-135mm and the 24-105L I replaced it with is very noticeable. But between a sharp and very sharp lens? Sure, you can tell the difference pixel peeping at charts and by looking at MTF numbers, but in the real world that doesn't matter.

I shake my head when people post crops of macro shots to look for problems.

For me, how does the photo look as it would actually be displayed? If I blow a shot up to 11X14", and it looks good, well, that's good enough for me...

BreitlingFan wrote in post #10894081
I shake my head when people post crops of macro shots to look for problems.

For me, how does the photo look as it would actually be displayed? If I blow a shot up to 11X14", and it looks good, well, that's good enough for me...

Yep, it's a bit like trying to critique the Mona Lisa by only viewing 25sq mm of the entire painting

six4 wrote in post #10893075
Going out and shooting is great - but sharpness cannot be quantified or compared in situations which are not controlled.

I guess I'll just stick with the ISO 12233 charts.

If you want to spend the rest of your life only photographing test charts, newsprint, batteries, brick walls etc then by all means go and shoot test charts, newsprint, batteries, brick walls etc..

Now,, if you want to step outside the box and do something really different,, go shoot a portrait, a landscape, a butterfly, your neighbour's cat or little Johnny playing football.. This is what lenses were designed to shoot..

Just simply take pictures, if they look sharp lens is sharp.

sandpiper wrote in post #10893975
Yes, sharpness is important. However, so are bokeh, colour, contrast, CA, barrel distortion, vignetting etc., most of which are either not going to show up on a test chart, or be very hard to judge how they will look in a real world situation.

I am completely aware that there are other elements of lenses that are important (as I stated earlier).

My post here was just to inquire how other people judged the sharpness of their lenses.

And (again, as I stated earlier), this is more for me because as a novice I often find it difficult for my eyes to differentiate "sharp" from "very sharp"

six4 wrote in post #10894966
I am completely aware that there are other elements of lenses that are important (as I stated earlier).

My post here was just to inquire how other people judged the sharpness of their lenses.

By looking at their images. Really, it's that simple.

lol. I almost feel as though my bringing up the shooting of charts to test lens sharpness is offending many people on this board

I just always read how people say their lenses are "super sharp" and have always wondered if people had a system in which they used to compare sharpness. I guess to my novice eyes - without a system in place - all my lenses look very sharp.

I apologize for asking a question that seems to peak some serious dissent

six4 wrote in post #10894966
My post here was just to inquire how other people judged the sharpness of their lenses.

by going outside and taking pictures?

seriously, who cares. if there are any problems they will quickly show through real world use.

Well, I was disappointed with my 400 F5.6 on my 40D. MFA on my 7D and 50DII made it the lens I thought I had bought, How'd I do my MFA testing? I set up a maniquin head at the distance I thought I'd normally be shooting the particular lens, put some small objects in front and behind in increments that made sense to gauge whether it was front or back focusing, then started shooting in manual exposure mode on a tripod.

Shooting static B & W scales didn't hold up in real world shooting. I did this with my 400 f5.6 and 70-200 f4 IS. Worked great, well worth the effort and it helped the 70-200 through the full FL range. Slightly different adjustments for the 7D and 5DII, so I chalk it up to the tolerances on the mount. Well worth the effort.

Many will say just go shoot, but when you have some serious cash tied up in lenses, especially if you have 2 weeks to return to the vendor, I see no problem with trying to sort out whether it's a good copy or not. Static testing is not a panacea, but it can certainly be a possible starting point for vetting out AF issues if done in a methodical manner.

As usual, your mileage may very.

six4 wrote in post #10895024
lol. I almost feel as though my bringing up the shooting of charts to test lens sharpness is offending many people on this board

I just always read how people say their lenses are "super sharp" and have always wondered if people had a system in which they used to compare sharpness. I guess to my novice eyes - without a system in place - all my lenses look very sharp.

I apologize for asking a question that seems to peak some serious dissent

No apology in order, you asked a legitimate question and got some feedbacks.
don't see the suggestions posted here as harsh or bullying, to a point that you feel you had done something offensive.

The feedbacks may not be what you were looking for originally (i.e.: test methods for lens sharpness), but I think most people here meant good (because we have too many pixel-peepers and brand-oriented freaks as it is). If your lens looks sharp to you, then you should be happy since that's all that matters.

As for why some people buy expensive equipments, and shoot charts to boast about sharpness - that's just their hobby. They're COLLECTORS (of photography gears).

Here's the Webster definition of PHOTOGRAPHY
: the art or process of producing images by the action of radiant energy and especially light on a sensitive surface (as film or a CCD chip)