I'm just getting serious into photography and have recently invested in a brand new fairly expensive Canon L lens. What are people's opinion on the quality of Canon L lenses right-off the factory? With my un-trained eyes, my test shots show sharp pictures. But with no past history to compare or other lenses to compare with, it may actually be not as sharp as it should be.
1. Now do people here generally just have their brand new lenses calibrated by Canon anyway or just on a need basis? Do lenses "lose calibration" after some time of normal usage and hence need to be "re-calibrated" once in a while?
2. Right after getting a new lens (brand new or used), how do people normally "test" the "goodness" of a lens? Is there a generally accepted procedure that photogs normally put their lenses through to ensure its quality?
mddauz wrote:
I'm just getting serious into photography and have recently invested in a brand new fairly expensive Canon L lens. What are people's opinion on the quality of Canon L lenses right-off the factory? With my un-trained eyes, my test shots show sharp pictures. But with no past history to compare or other lenses to compare with, it may actually be not as sharp as it should be.
What lens did you buy?
1. Now do people here generally just have their brand new lenses calibrated by Canon anyway or just on a need basis? Do lenses "lose calibration" after some time of normal usage and hence need to be "re-calibrated" once in a while?
I let Canon Service check every new lens I buy and let them calibrate them when needed to my cams. After that I'll only let Canon Service have a go at it when performance drops for whatever reason.
2. Right after getting a new lens (brand new or used), how do people normally "test" the "goodness" of a lens? Is there a generally accepted procedure that photogs normally put their lenses through to ensure its quality?
Just shoot, shoot and shoot and have a critical look at the results. There are lots of reasons why pics can be unsharp. Some related to hardware problems, other related to user errors. I guess it comes down to experience to know the difference.
If you take some shots of subjects with fine details, and then look at them at 50% on screen. If they look sharp and detailed, then the lens is fine. Make sure you do a little sharpening first in post processing. If you have photoshop it is called "unsharp mask", and simple basic settings should be 300%, .3 radius and 0 threshold.
Oh, and no I've never had to calibrate a lens (although I did try 1 used lens that needed to be calibrated, but that is a different case). Lenses can get out of alignment from being banged around. I think it is probably a relatively rare thing, but only the folks who've had a problem make posts about it.
1. Now do people here generally just have their brand new lenses calibrated by Canon anyway or just on a need basis? Do lenses "lose calibration" after some time of normal usage and hence need to be "re-calibrated" once in a while?
No and maybe (depending on how you use your lenses).
2. Right after getting a new lens (brand new or used), how do people normally "test" the "goodness" of a lens? Is there a generally accepted procedure that photogs normally put their lenses through to ensure its quality?
Since you have to ask, welcome to the club
You can pretty much do everything in Matlab, IDL, etc. if you know what you are doing and are fluent with signal/imaging processing.
"Hi, I am Canon 10D, and I am a recovering pixel peeper."
Here's my advice, don't get into pixel peeping. It can be very addictive. Chances are your lenses are perfect if you don't notice anything unusual during normal use. If you are happy with your lenses, don't peep. Pixel peeping can make you unhappy once you started to look for even the tiniest imperfection in your lenses. A happy photographer makes happy images
There is a difference between wether a lens is sharp or wether a lens focuses correctly (or not). Of course when a lens doesn't focus correctly it appears to be unsharp. To determine if a lens is sharp (or not) it is best to do some tests by focusing manually. This way you rule out any possible AF problems. To determine if a lens is focusing properly, try this test: http://focustestchart.com/focus21.pdf or have the lens checked by Canon Service.
on page 33, section "Testing your own cameras and lenses"
4) compare testing results to other lenses i own. if you feel that the results are not up to par, go back to the store and exchange the lens immediately. of course some lenses will be sharper than others (example: prime vs zoom) but you can kinda tell if a lens is shitty or not, if you've done a lot of testing before. if it's your first time, you may need to borrow an identical lens from a friend so that you have some basis for comparison.
5) repeat above procedure until you are satisfied.
do not wait until your store return/exchange policy expires to test your lens. if it is shitty, you will end up with the hassle and it will cost you to send it to canon for calibration and fixing.
Daan B wrote:
There is a difference between wether a lens is sharp or wether a lens focuses correctly (or not). Of course when a lens doesn't focus correctly it appears to be unsharp. .
I totally agree with Daan B, and I would like to add that there is a difference between sharpness or resolving power of a lens since I have seen too many times people ask "are L lenses sharper than non-L lenses?", "is my lens sharp?", etc.
Basically, you can increase the sharpness of an image during post-processing using Unsharp Mask, etc., but you can't increase its resolving power.
Canon has good quality control to rival other manufactures. Sigma does not! One reason that people "Calibrate" lenses is that Canon will do it under warantee and, out here in CA, they do it well and fast. That lenses can use tweaking for an individual body is undeniable because new Canon 1 series bodies will do it internally (AF micro adjust). But there can be other issues with lenses-especially zooms and certain designs discussed on this forum.
Daan B wrote:
There is a difference between wether a lens is sharp or wether a lens focuses correctly (or not). Of course when a lens doesn't focus correctly it appears to be unsharp. To determine if a lens is sharp (or not) it is best to do some tests by focusing manually. This way you rule out any possible AF problems. To determine if a lens is focusing properly, try this test: http://focustestchart.com/focus21.pdf or have the lens checked by Canon Service.
Well said.
This should be the standard response to every sharpness thread on this forum. Every time I say it I get flamed so I guess you said it better than me! .
mddauz wrote:
I'm just getting serious into photography and have recently invested in a brand new fairly expensive Canon L lens. What are people's opinion on the quality of Canon L lenses right-off the factory? With my un-trained eyes, my test shots show sharp pictures. But with no past history to compare or other lenses to compare with, it may actually be not as sharp as it should be.
1. Now do people here generally just have their brand new lenses calibrated by Canon anyway or just on a need basis? Do lenses "lose calibration" after some time of normal usage and hence need to be "re-calibrated" once in a while?
2. Right after getting a new lens (brand new or used), how do people normally "test" the "goodness" of a lens? Is there a generally accepted procedure that photogs normally put their lenses through to ensure its quality?
1.) I've never had to have a lens calibrated or anything else from Canon...not even my nine-year old 28-70L. I'm of the adage, "If it ain't broke, don't fix it". I'll only send in a lens to Canon if there is a problem.
2.) I test my lenses by using them in the real world (as opposed to lining up batteries on the shelf). I shoot subjects that I would normally find myself shooting. Personally, I'm not a believer in home testing using focus charts either...too many variables to control outside of a lab environment. If I'm not happy with the way the images look, then I'd have to consider sending in the lens. Maybe I'm lucky, I don't know...but I have yet to have a need for any type of service. Now that I jinxed myself...
TBH...your chances of getting a "good" lens far outweigh your chances of getting a "bad" lens. Its just the "bad" ones that you hear about. If there were "my lens is great out of the box" threads, there'd be no room on the board for anything else.
