Have attached the original picture. All the trees in the top left hand bracket look a little bent. I checked the other photo's (different subjects) each side and they are fine, but as I said the three brackets are identical except for exposure. Maybe its the type of tree and wind?





Hi Peter -

This is easier to see now. (I asked him to send me a full size image for a better look)  Do you remember where your focal point was?  If you load it in DPP it will show you, but to me it looks like the lower third center.. Which if you consider the distance, the lens, the focal length, you're simply realizing the limits of this particular lens. 

If I'm right about your focal point, what you're doing is in a way.. you're amplifying the faults of the lens.  The natural softening in the corners in this case.  It's just not the tree, but the grass in front of it and pretty much equally on both sides.  The one tree on the left seems even more exaggerated because it has a different type of foliage than the other trees.  The other trees have distinct leaves, while the tree in question seems to have a sort of 'streaming length' to it.  For sure it's a different type of tree, and I think the difference in just an exaggeration of the softening in the corners/edges. 

If you had picked a focal point based on the circle of confusion, or more easy to understand, halfway (not in the frame distance, but in actual distance) between the foreground and background, then at F10 you wouldn't be seeing too much of the softening around the edges/corners at F10.  But if you were focusing on the near bank (tall brown weeds) or maybe even the far bank, then it could do exaggerate the effect.  Looking at the bank closest to you, it appears to be focused, but not in sharp focus.  This is the sharpest area of the frame, but it's not as sharp as it should be.  At 1/80th it could simply be camera shake reducing the sharpness. 

So in other words.. a perfect storm of errors/effects in the focal point, shutter speed, and natural limitation so the lens. 

Interesting effect though.. and I could always be wrong.  Mine is only an educated guess.  If I knew the focal point I'd be more certain. 

If I'm wrong, and even if I'm right, I'd recommend doing a 'wall test' with that lens.  I really don't think it’s the lens because I've seen some very sharp results from you using it.. but a wall test (a brick wall with details and lines) would quickly show you the max level of detail in the center, with a consistent outward level of detail to compare against.  The lines would show you distortion. 

I hope this has been of some help.  For sure it's been fun!



This next question comes from the forums. 


Hi Steve

I like the idea of having a grid on the view finder of my camera to help me think better about composition before I push the shutter but I dont understand why the optional Canon "Eg-D precision matte with grid" has 3 horizontal and 5 vertical lines. I was looking for something that would give me a grid aligned to the rule of thirds (ie 2 horizontal and two vertical - or 9 boxes. Is the EG-d grid designed for an entirely different purpose?



Peter -

Well.. it's like this.. ;o)

I wouldn't want a grid in the rule of thirds theme.  I think if you keep with foreground, mid-ground, background.. the rule of thirds will follow naturally.  The biggest skill is learning to "see" the scene.  You'll 'see' with the naked eye, frame with the viewfinder, and add to the creation process with camera controls like depth of field.

The lines you refer to are there to help "level" the horizon.  The vertical lines help you do this by lining up a vertical line with a vertical feature in the scene, and the same with the horizontal lines.  Ideally you'd check both vertical and horizontal at the same time.

Yet, you can certainly get a rule of thirds grid custom etched.  I wouldn't bother with the Canon models though.  They're lacking in many ways.  Instead visit and check out their awesome focus screens.  The professional #5 model features a HUGE split diagonal prism which makes accurate manual focus fast and easy.. and you can custom order any line etchings you wish at the time of order.

I have several for each camera body I own.  They all have the large #5 Pro diag split prism because while Autofocus is great, the next level up in skill and creativity will be when you override the AF with manual focus.  And I have screens with 5x7", 8x10" etchings depending on what my client wants their wedding album or senior book to be sized.. and I have another with simple crosshairs that I use line up horizons.

Yes, they're pricey.. but well worth it.  Remember, the focus screen affects the accuracy of your AF, MF, and light metering.  When something can affect that much of the process you'll want to get the best and Brightscreen is the best without question.

Next time we get together remind me and I'll show you a 1 series body with one of these screens mounted.

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