The Little House in the Daffodils (Last Day of Winter 2013, North Carolina Style II)

Hi Lannie,

This is a wonderful presentation.

The colorful scene and clarity presented are well seen.

Technically, the only aspect I would have changed is the ISO. ISO 200 would have worked well, as with a 20mm focal length lens, a hand held exposure of 1/640 second would be more than adequate to assure a vibration free capture, especially for a still scene.

The distortion seen in your image changes with the effective focal length setting. Barrel distortion is quite common in wide angle lens, especially zoom lens.

There are more specialized rectilinear designs in fixed focal lengths that address distortion to a very high degree of correction. Desk top programs and plug-ins allow for various lens to be corrected in post processing, too. Many cameras have "look up tables" thast address the primary design aspects of the lens.

Another factor in controlling distortion is the perspective and working distance used to make the capture. Many times, care with centering or leveling the camera will result in some compensation for the lens distortion present. Generally, using the longer focal length of a wide angle zoom also results is less distortion effects, too.

Best Regards my friend, Mike

Of course!   Only in this case it is not barrel distortion but pin-cushion distortion!  How silly of me not to see it for what it was.  It is not so obvious in this case (for me), since it does not "show" down the entire vertical line of the photo--since the vertical lines are so short.  Yes, I could have corrected for "pincushion v. barrel distortion" in PS before cropping it, etc., if I had recognized it for what it was.  Thank you, Mike!

 

What puzzled me was that it was not visible in the two church shots, one (Methodist Church) before these house shots and one (Lutheran Church) after them.  Actually, it is no doubt there, but simply overwhelmed by the massive typical wide angle effects of looking way up--which I did with the church spires, but not here.

 

Always good to have a lens designer as a friend and critic!  Thank you, BIG MIKE!  I could have solved it with "perspective correction," but that would not have been the real problem here--although it would have treated the most obvious and visible symptom.  It was more of an intellectual problem for me than a real problem, but, if I ever decide to print, I will want to correct it.  I might, anyway, even for web display, since now it is going to grate on my eye till it is fixed.

 

Thanks again, Mike.  You have, by mentioning "barrel distortion," reminded me of the opposite effect of "pin cushion distortion," which you well know is the other pole of the same effect.  Why did I not think of that?!

 

--Lannie

You are also right about the unnecessary two extra stops I built in by choosing ISO 800 rather than 200.  I just wanted to be sure that there would be no motion blur on that BIG, PIXEL-LADEN SENSOR, but ISO 800 was definitely overkill.  Not obvious on a small display, the concomitant noise would certainly make a difference on certain displays. Thank you for reminding me not to overdo the preventative measures, which cause problems of their own.

 

Thanks again, Mike!

 

--Lannie

As for shooting wide open, I will have to experiment with this lens, Mike.  I just used it for the first time yesterday.  I got it for about $550 off on eBay, and it is a beauty!  It is a bit softer in the corners wide open at 17mm than I was expecting, but I am very happy with it.  At least I have the f/2.8 if I need it, and, if I need to stop down for the corners, well, I can do that, too, with the help of my trusty Gitzo and Manfrotto friends.

 

In spite of the fact that this is not the proverbial "perfect lens," I can see why it is widely perceived as a professional grade lens.

 

Now if I can just get a really good medium zoom, I will be set on the zoom front.  I might not ever get the primes I would like, but I'm happy.

 

--Lannie

Hi Lannie,

I use my Nikkor 17-35mm for portrait work , model photography on the beach and wedding photography. It is a nice all around short focus zoom.

I avoid using most zoom lens that have more than a 3 to 1 ratio because of optical compromises that happen due to design constraints.

I use fixed focal length lens for most landscape type work. I also use many different rectilinear designed lens , too. Then post processing requirements are not required to compensate for any lens distortions.

Best Regards my friend , Mike

I love this, but why wouldn't I? I took it! I hope somebody elselikes it, too. Comments welcome.

--Lannie

bold bold bold. I like it. j

Thanks, Jamie.  I need to fix the pincushioning, but otherwise I am pleased that this simple hand-held shot came out so well.  This was my first day out with this lens.  This was shot less than a mile from my house.

 

--Lannie

my grandmother used to refer to me as a pincushion because of all the shots i took every week.  looks good in this picture though.  best, jamie

If the house were close to the edge of the original file, you would sure notice the distortion!

 

--Lannie

As you know, Jamie, the distortion is easily fixed in Photoshop.  I need to run this file through PS again.  I have to say, though, that with the subject this far from the edge, the distortion is not particularly noticeable.

 

What was surprising was that I was getting pincushion distortion at the wide end.  I would have expected barrel distortion there.  This was shot at 20mm, not 17mm.  I have a better feel for this lens now from this single outing--where it is strong, where it is not so strong.

 

--Lannie

I like this one with the house set back a little and the daffodils carpeting the foreground. The little place seems almost enchanted in a benevolent Brothers Grimm sort of way.

Persian rugs are all said to have a flaw to remind us of our fallibility.

 

twenty is wide enough that you have to keep the lens level.  if the subject isn't precisely fronto-parallel, there will be some convergence. that is not distortion, but only correct perspective. if you take one picture front parallel and there is no distortion, then there should never be any distortion at that focal length.

 

the brain readjusts perception toward squareness for real scenes, but not for pictures of real scenes. that's why we notice it in pictures. there's an art to taking out just enough but not too much.  best, j

 

p.s.: benevolent Brothers Grimm? I didn't know there was another family of Grimm brothers. I only know the pitiless ones.

 

p.p.s.:  Neither Fish nor Fowl - It is probably only we beasts of the earth who would suffer this problem.  Creatures of the water or of the air would probably just rise to a more front-parallel position.

"there's an art to taking out just enough but not too much."

 

Wow, that is so true, Jamie.  This particular shot shows a tiny bit of pin-cushion distortion, but it I probably won't try to fix it unless I decide to print it.  Other pictures of this house posted in this folder show significant pin-cushion distortion at the WIDE end, which is where I would have expected to find barrel distortion (as I think I already said above).  In one I definitely took TOO MUCH OFF when I tried to correct with the lens distortion filter on Photoshop.  I need to go back and redo that one, or else use perspective correction to fix only the right side.  That should be close enough.

 

--Lannie

Jack: Thanks for the comment and for the allusion to the Brothers Grimm.  It is a kind of fairy tale design, I think.

 

--Lannie

it's hard to get it right in Photoshop.  I started keeping the lens level, even if it wasted half of the sensor.  It's the poor man's equivalent of a shift lens.  it works beautifully, though, if you're willing to crop out half.

 

it's worth playing in Photoshop, though.  there's always that chance that the image will ''Snap'' into place.  best, j