RF800mm F11 IS STM Images do not seem sharp...ringing around image

[dcomora]

I am new to Canon products and recently purchased an R5 with the the RF 800 fixed f11 lens.  I have been shooting birds over the past few months.   I have been comparing my shots to those I see posted on line and it seems I am not able to get the sharp focus that I see others getting.  I am using the animal eye focus setting, I am shooting at  shutter speeds of  between 1000 and 2000, my ISO is usually never above 2000.   I have the image stabilization engaged and I most recently used a tripod.   When I zoom into my images, I see a little "ringing" around the outside of the birds and birds eyes.   Someone said I should use Topaz AI sharpen to get sharper images, but I am thinking that should not be necessary.  Is it possible that the lens is out of calibration or am I still doing something wrong?  I also have an R 25 - 105 lens and photos are super sharp. Any advice would be appreciated. 

[dcomora]

Just took a similar shot with the 800mm lens using manual focus and lining up the diamonds...on tripod.  still seems unclear. 

[Waddizzle]

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@dcomora wrote:

Just took a similar shot with the 800mm lens using manual focus and lining up the diamonds...on tripod.  still seems unclear.

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I do not know why you switched to manual focus.  You've introduced human error into the equation.

But, how far away was your subject.  Your DoF should be narrow.  Take a look at the DoF in the f/11 column at various distance to the subject.  It is pretty narrow.

[wq9nsc]

I didn't see the answer to KV's question about how far you were from the subject but even at f11, the depth of field of an 800mm is very shallow unless you are a long distance away. 

The attached photo was shot with an EF 800 f5.6 and EOS 1DX III at about 40 feet with a usable depth of field of around 2" and it shows.  Even at f11, the DoF would be under 5" at that distance.

Rodger

[kvbarkley]

It is always possible you got a bad one:

[Mod note: Removed link per Community Guidelines - Third Party Sales (on that site). Sorry.]

Link Referenced: Bob Atkins Site: Lens Testing. A guide to testing camera lenses

(On this lens you have to be far away - the MFD is about 20 feet!)

[ebiggs1]

" I would not use eye detect. It really doesn't matter when you are 100 yards away!"

I agree turn this off. Also IS doesn't help at the SS you are using, in fact it may hurt. Turn it off, too.

Yous samples do appear soft but we need to discover the reason. Keep in mind a lot of factors effect the IQ of a super tele.

In the first place it will never be as sharp as any of your shorter FL lens like your 24-105mm. The biggest factor with how sharp a tele is is distance. As distance increases resolution decreases. In other words the farther away you are will result in less IQ.

A misconceptions about a super tele is to use it to shot far away subjects. Although it can do the the best use is shooting a small subject,a bird, at close range. Making the small 'bird' appear larger in the frame.

[dcomora]

Thanks for your post.  When I Zoom into your photo, I am not seeing any of the ghosting or ringing that I am seeing with my 800mm lens.  This is more along the lines of what I expected to see with my lens, which makes me think there may be an issue with the lens.  I have tried animal eye focus, spot focus, manual focus and I cannot get a real sharp image with the lens.  My bird shot that I posted earlier was about 40 feet away.   

[dcomora]

Hi, Thanks for this great information.  The reason I went to manual was a couple of the posts I received said they wouldn't use the animal eye focus, and suggested manual, which I think was worse than the animal eye.   I appreciate the chart and I have to say that I have been shooting for 2 months with this lens and I don't think I"ve gotten one shot that I am happy with, in terms of focus.  Many of my subjects were still or barely moving, lately all on a tripod.  I'm thinking about going to Unique Photo and renting the same 800mm lens and seeing if the result is better. .My only other lens at this point is the 24 to 105 and I am not seeing any of the ringing or ghosting around the images when I blow those images up....but I realize the depth of field is much greater. 

[Waddizzle]

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@dcomora wrote:

Thanks for your post.  When I Zoom into your photo, I am not seeing any of the ghosting or ringing that I am seeing with my 800mm lens.  This is more along the lines of what I expected to see with my lens, which makes me think there may be an issue with the lens.  I have tried animal eye focus, spot focus, manual focus and I cannot get a real sharp image with the lens.  My bird shot that I posted earlier was about 40 feet away.   

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I would not expect particular good results with any of those focusing approaches.  

As I pointed out earlier, Eye AF only works when you use one of the Zone AF point selection modes.  It does not work with just a single AF point.  If you only had a single AF point enabled, such as Spot AF, then your Eye AF could never turn on , even though you may have selected it to be enabled.

Testing using manual focus is good advice, but you need to select better test subjects or targets.  Casual photos such as those you have posted can easily lead you to the wrong conclusions. You need positive confirmation of where you are focused.

Also, what software you using to process the images?  If you are using the Canon DPP4 software, it can show you where you locked AF point is located, assuming that you actually had a locked AF point when the shutter fired.  

You could have a bad lens.  If you are taking test shots on a tripod, then I highly recommend using the shutter delay timer.  I would also shoot in Av mode, ISO 100, and let the camera calculate the correct shutter speed.

[ebiggs1]

"Zoom into your photo, I am not seeing any of the ghosting or ringing that I am seeing with my 800mm lens."

You can't do that because your photo is OOF or camera movement or something else. So comparing it to a good shot and trying to analyse it is fruitless.

They very first thing you need to do is test it.  You need a good subject that is flat like a newspaper. Tape it to a wall and make sure it can't move. Now mount your gear on a "sturdy" tripod. set ISO 400 or so. Good bright daylight. Use One shot never AI-servo or any other mode. Just the center focus point. No IS, turn it off. Take some shots and vary the f-stop and the ISO. Always Raw never jpg. And for this test P mode is fine! Let the camera/lens do the focusing, not you.

This will tell you what you have.  It will also tell you if the problem is with the gear or yourself. If you have Photoshop open the Raw file with it and do the customary adjustments in ACR. Or, if you have something like Dropbox u/l a unaltered sample Raw and I will open it in PS for you.

[dcomora]

I was able to rent the same RF800 F11 IS STM lens from my local Unique Photo this afternoon and I did some comparison shooting.  The images I collected handheld of birds in flight were amazing.  I swapped the rental lens with my lens and took a couple of handheld shots for comparison.  I'll post them below.  The first is of a cell tower.  The image on left is the rental lens.  The difference between lenses is obvious, especially if you zoom in.