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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

[ Edited ]

@RobertTheFat wrote:

@ebiggs1 wrote:

"The lens focuses a little faster and sharper on distant objects in the 2.5M position.  When it is set to 1.5M, the result is shots that look like these.  Sharp, but not quite tack sharp."

 

Now you and I both know that is ridiculous and nonsense.  The lens may and does focus slower when on 1.5m~inf. compared to 2.5m but not any less sharp. A lens does not can not change it's "sharpness".  They are what they are from day one and on.


No, the lens doesn't change its sharpness. But that doesn't necessarily guarantee, in any given situation, that it will exhibit the same focusing accuracy in both switch positions. It may in fact be so, but to dismiss as "nonsense" the possibility that it isn't, seems a bit of a stretch.


In my experience the lens is not as sharp (meaning focus is not as accurate) at distant objects in the 1.5M position compared to the 2.5M position.  This AF is slower to focus on objects more than 4 meters away with the switch in the 1.5M.  

 

This is readily apparent when you shoot in continuous drive mode with high fps body like the 7D2 using AI Servo focus mode.  With 2.5M, the lens focuses keeps up with the 10 fps on distant subjects, beyond 10 meters.  With 1.5M, the lens does not quite keep up with the 10fps frame rate.  I have switch Image Priority to Focus Priority.

 

Maybe, I have a bad copy.  I had issues with the first one, which I had ordered online through Best Buy, and had to return it for an exchange.  The lens was making a clicking sound because it would seat snugly in the camera mount.  Turns out that it was missing the rubber sealing ring.

 

[EDIT]. But, like I pointed out earlier.  If the switch position does not make a difference, then why did they add it?  

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

"It may in fact be so, but to dismiss as "nonsense" the possibility that it isn't, seems a bit of a stretch."

 

Not to me. Not a bit. 

I have shot as many super telephoto shots as anyone. I have or have owned all the current super 150-600mm zooms. Any lens can misfocus but that is not the same thing as saying it isn't as sharp. Its sharpness can not change, it can misfocus.

Personally none of mine or at least none I have noticed missed focus because I had it on 2.5m vs 1.5m or whatever limits the lens has.  They focus slower for sure.   It is nonsense!

EOS 1DX and 1D Mk IV and several lenses!
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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

So after further testing, it seems everything is fine. The photos were in focus, but maybe a tad soft. I don't know if my expectations are reasonable in terms of sharpness at this distance with this size subject, but when I zoom into 100% in Lightroom, it just doesn't have that same crispness that I see with other lenses I use more regularly (like my 24-70 2.8 L or 35mm native EOS R lens). It looks plenty sharp at this size, but 1:1 in Lightroom looks softer. Nothing a little sharpening can't fix though I suppose!

 

Below is one of my test images shot on manul at 1/1250 sec f2.8 ISO 400. I had the lens stationary on a table and used the 2sec timer, zoomed in to 200mm. IS was on, mode 1, and I had it set to the 2.5m-infinity setting (which are the same lens settings I had in the initial trouble shot of the squirrel).

 

I suppose I just missed focus on that first shot, but my curiosity came from wondering HOW it focused where it did. I know it's possible the focus point wasn't as precise as it looked in the viewfinder, but I would think if I missed the focus point in any direction aiming for the squirrel, a different part of the photo would have been in focus (like the pot, or the grass immediately to the top of squirrel's head). In order to focus on the grass that was in focus, I would have had to have been focusing way down and to the left, or way down and to the right from the center/squirrel.

 

I tested this same shot below at f4 and f5.6. All were in focus and none seemed any sharper to me than the others at 100%.

 

I will continue to test some more real-life examples and hopefully I get better results than my initial test shots. I hope that I can use the lens handheld though as that is more practical for my use and it's not always possible to use a tripod with a timer. When hand holding the camera with this lens, I can hear the IS motor going as I move the camera around. I assume that is a normal function of the image stabilization system but sometimes I wonder how much noise is normal and how much is cause for concern.

 

Thanks for taking the time to read and comment. Appreciate the help.

 

lens test 1/1250 sec f2.8 ISO 400

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

"... it just doesn't have that same crispness that I see with other lenses..."

 

This is a 100% crop of the sample you displayed. It really looks pretty good to me.

100percent.jpg

I did lens correctoin.  Did you do that when you imported it to LR?

 

"(like my 24-70 2.8 L or 35mm native EOS R lens)"

 

You do realize that lens resolution decreases as distance increases?

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

"Below is one of my test images shot on manul at 1/1250 sec f2.8 ISO 400. I had the lens stationary on a table and used the 2sec timer, zoomed in to 200mm. IS was on, mode 1, and I had it set to the 2.5m-infinity setting (which are the same lens settings I had in the initial trouble shot of the squirrel)."

 

Does "manul af" mean that you  switched the lens to MF, and focused manually?

 

The subject is pretty far away.  You need to be  at 25-50x the focal length that you are shooting.  This works out to roughly 10 meters, 39 feet, for a 200mm lens.  Use the standard AF point size, with One Shot AF.

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring


@ebiggs1 wrote:

 

I did lens correctoin.  Did you do that when you imported it to LR?

 


I did not. I will try that. 

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring


@Waddizzle wrote:

 

Does "manul af" mean that you  switched the lens to MF, and focused manually?



 No, that should have been "manual" obviously but it says manual AT not manual AF. I was on manual mode (not Tv or Av etc). I had it on auto focus using center focus point on one shot. 

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring


@cdisimone wrote:

@Waddizzle wrote:

 

Does "manul af" mean that you  switched the lens to MF, and focused manually?



 No, that should have been "manual" obviously but it says manual AT not manual AF. I was on manual mode (not Tv or Av etc). I had it on auto focus using center focus point on one shot. 


Got it.

 

"You do realize that lens resolution decreases as distance increases?"

 

The flip side of that coin is your AF sensor works with less resolution, too.  This is exactly why using Spot AF on distant subjects does not work very well.  Retest at a distance that is 25-50x the focal length.

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

"I did lens correction.  Did you do that when you imported it to LR?

I did not. I will try that."  Smiley Happy

 

You should do lens correction as a preset (and any other setting that applies to all your photos) when importing to LR. You may want to add some sharping too.  As, Raw files do not get any sharping in the camera the way jpg do.  That is why a jpg can look sharper than a Raw at first.

 

"Retest at a distance that is 25-50x the focal length."

 

This is a standard recommendation for focus adjustment. In this case it really is meaningless as our test was to duplicate the shooting conditions in the original shot. Besides sometimes certain distances are more important than others. That is why that figure is just a suggestion.  Apparently your camera has no focus adjustment anyway.

 

I really don't think you have a problem.  You simply missed that original shot.  There is and end to it.  Go make some beautiful photos!

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Re: Help with focus: Canon EOS R with EF 70-200mm f/2.8 IS II and adapter ring

"... shot on manul at 1/1250 sec f2.8 ISO 400."

 

Not that I have anything against M mode but may I suggest you get up close and personal with Av mode.  I think you will really like it.  You can set a lower and upper limit to your SS if you like.

 

My favorite settings for smaller animals and birds is Av and I usually set the lens down one stop. I fix the ISO for the conditions but good daylight ISO 800 works.  Average WB but this doesn't matter because I always shoot Raw.

 

This is nearly a 100% crop of the finch.  I am hand holding my Sigma 150-600mm S super zoom at 600mm. Av mode f5.6, 1/6000, and ISO 1600. One shot and just the center focus point. Full range of the lens too.

 

_OS11649.jpg

It has lens correction and some selective sharpening upon import in to LR.

 

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