# IS mess up the edge sharpness of EF-M 11-22 on M50



## Rocky (Dec 31, 2018)

I just notice that the edge sharpness of my 11-22mm on my M50 is not good. After investigation, I found out that is caused by the IS function of the lens. I tried the lens on my M2. It has the same problem. Due to the lower resolution of the M2, the problem is not that obvious. Has anyone seen similar problem?


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## neuroanatomist (Dec 31, 2018)

I went back and looked at the uncropped IS test shots from my M11-22 review, and the edges (well, the one edge with subject matter other than a blank wall) doesn't seem noticeably soft. However, that was my first review and only with subsequent lenses did it occur to me to have a tripod shot for comparison, so I can't say definitively that there's no loss of edge sharpness with IS on the M11-22. 

Would you be willing to share your test images? 

Also, are you giving the IS time to 'settle in'? It takes about 0.5 s for the IS system to effectively stabilize. In prior testing with the 100/2.8L Macro and 600/4L II, I found that if you just press the shutter from finger off to image capture at one go, the result can be _worse_ than handholding without IS.


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## privatebydesign (Dec 31, 2018)

neuroanatomist said:


> In prior testing with the 100/2.8L Macro and 600/4L II, I found that if you just press the shutter from finger off to image capture at one go, the result can be _worse_ than handholding without IS.



^ This!

I have found this to be true with all the IS lenses I own, 100L Macro, 70-200 f2.8 IS, 300 f2.8 IS, 35 f2 IS, took me forever to come to the realization that it was user error.


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## Mt Spokane Photography (Dec 31, 2018)

Thats one thing I don't like about IS, you must wait for that first shot for it to stabilize. With a long lens, I don't often have a choice, but for normal or wide lenses, I think that it is better turned off except for the 2% where its needed.


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## Rocky (Dec 31, 2018)

neuroanatomist said:


> I went back and looked at the uncropped IS test shots from my M11-22 review, and the edges (well, the one edge with subject matter other than a blank wall) doesn't seem noticeably soft. However, that was my first review and only with subsequent lenses did it occur to me to have a tripod shot for comparison, so I can't say definitively that there's no loss of edge sharpness with IS on the M11-22.
> 
> Would you be willing to share your test images?
> 
> Also, are you giving the IS time to 'settle in'? It takes about 0.5 s for the IS system to effectively stabilize. In prior testing with the 100/2.8L Macro and 600/4L II, I found that if you just press the shutter from finger off to image capture at one go, the result can be _worse_ than handholding without IS.


Thanks for the advice. Do you mean that I need to half push the shutter to activate the IS , wait 0.5 seconds, then push the shutter all the way down to take the picture???


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## neuroanatomist (Dec 31, 2018)

Rocky said:


> Thanks for the advice. Do you mean that I need to half push the shutter to activate the IS , wait 0.5 seconds, then push the shutter all the way down to take the picture???


Yes, exactly. 

Keep in mind that IS allows handholding at longer shutter speeds than otherwise possible, but doesn't do anything for moving subjects (where you want to stop action, that is...I love IS for handheld waterfall shots). Generally, that means scenes where IS will benefit aren't changing quickly, so the delay isn't an issue. If you need to take quick shots, turn IS off. This is one area where the minimalist design of the M lenses is annoying, no switch on the lens to do that rapidly. I do have my M6 set to display from My Menu, and IS Settings is on My Menu.


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## Rocky (Dec 31, 2018)

neuroanatomist said:


> Yes, exactly.
> 
> Keep in mind that IS allows handholding at longer shutter speeds than otherwise possible, but doesn't do anything for moving subjects (where you want to stop action, that is...I love IS for handheld waterfall shots). Generally, that means scenes where IS will benefit aren't changing quickly, so the delay isn't an issue. If you need to take quick shots, turn IS off. This is one area where the minimalist design of the M lenses is annoying, no switch on the lens to do that rapidly. I do have my M6 set to display from My Menu, and IS Settings is on My Menu.


Thanks again, John. I will give it a try and let you know the result in the next few days. 
Happy new Year to you and your family. Also Happy new Year to members of the forum.


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## AlanF (Dec 31, 2018)

One of the advantages of back-button-focussing is that you usually engage the focus and IS well before actuation (maybe that's one of the reasons I get poor battery life as I use BBF all the time but no problems with IS).
I have had two copies of the 11-22. The first was fine at 11mm but very soft at on the right edge at 22mm and weaker on the left. The second is pretty good. I made some graphs of the results plotting Focal Quality of Focus across the frame (used some tricks to get these). Top are the results at 22mm, with my new copy in red, old in blue. Bottom is at 11mm. The IS doesn't appear to be affecting the new copy.at 22mm, and both are very sharp all the way across at 11mm.


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## AlanF (Dec 31, 2018)

I also compared the new 11-22mm, my 22mm f/2 and 15-45mm at 22mm, 22mm, and 21mm respectively. Wide open they are all very similar, but the prime get ahead at f/4. The prime doesn't have IS, and IS doesn't appear to be lowering the other 2. The 15-45 is actually very good, despite its reputation.


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## Rocky (Dec 31, 2018)

I went out earlier to try out Neuro and Mt. Spokane's suggestion. They are right. Wait 1 second makes a difference with IS. Will post sample images in a few days. the problem is at area closed to the left edge. Center is ALWAYS sharp


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## koenkooi (Jan 1, 2019)

neuroanatomist said:


> Also, are you giving the IS time to 'settle in'? It takes about 0.5 s for the IS system to effectively stabilize. In prior testing with the 100/2.8L Macro and 600/4L II, I found that if you just press the shutter from finger off to image capture at one go, the result can be _worse_ than handholding without IS.



Isn't IS always engaged on the M series? I think you can only run into the 0.5s issue if you wake the camera from sleep with the shutter button, regular on/off takes relatively long to be ready for the first shot.


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## neuroanatomist (Jan 1, 2019)

koenkooi said:


> Isn't IS always engaged on the M series? I think you can only run into the 0.5s issue if you wake the camera from sleep with the shutter button, regular on/off takes relatively long to be ready for the first shot.


The IS motors are running when the display is active but then, they're running even when IS is disabled in the menus. With EF-M lenses (and I believe RF lenses, too), the IS system must be powered even when the image isn't being actively stabilized (whereas EF/EF-S lenses can 'park' the IS elements). I don't think the IS is actively stabilizing on a continuous basis. I think it does if AF is active, but I suspect most people deactivate Continuous AF (I did, immediately).


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## Rocky (Jan 2, 2019)

At least 3 pictures were taken under different condition. WORST picture was chosen for pixel level illustration.

Full picture with reduced size ISO 100, f8, 1/500. 22mm, IS off , focus at the grey Vent.



Vent at pixel level, IS OFF



Vent at pixel level, IS ON, no stabilization



Vent at pixel level, IS ON, 1 second stabilization


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## koenkooi (Jan 2, 2019)

neuroanatomist said:


> [..] but I suspect most people deactivate Continuous AF (I did, immediately).



Same here, I might give it a try again if I get an M with DPAF, but I suspect I will hate that as well


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