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David Stephens
11-21-2013, 01:46 PM
http://farm6.staticflickr.com/5501/9379716012_633aed6dbe_b.jpg (http://www.flickr.com/photos/dcstep/9379716012/)
Starburst (http://www.flickr.com/photos/dcstep/9379716012/) by dcstep (http://www.flickr.com/people/dcstep/), on Flickr

Taken with a Sigma 15mm f/2.8 diagonal fisheye lens on my Canon 5D MkIII, standing about 3-feet from the tree.
ISO 800, f/16, 1/250-sec. with Raw conversion and de-fishing in DxO Optics Pro 8.0.

Douglas Bolt
11-21-2013, 03:38 PM
Cool! What is "de-fishing"? Something to do produce a straight horizon?

David Stephens
11-21-2013, 03:46 PM
Cool! What is "de-fishing"? Something to do produce a straight horizon?

Yes, that's basically it, along with correcting a ton of barrel distortion that's typical with a fish-eye lens. I find that it really increases the utility of my fish-eye lens.

dankearl
11-21-2013, 11:59 PM
The sunburst is nice, the horizon stills looks odd.
Why would you shoot with a fisheye and then try to straighten it?
Isn't the point of having a fisheye lens to take unusual photo's?
Just wondering......

Rachel Hollander
11-22-2013, 10:10 AM
Hi David - I agree the sunburst is nice and so is golden tone of the wheat(?). The horizon seems to need some ccw rotation. There's something light blue in the wheat about halfway between the tree and the left edge that draws the eye. I'm also not sure what it is.

TFS,
Rachel

Don Nelson
11-22-2013, 11:20 AM
Interesting use of flare in the image.
Others have already commented on the rotation - rotation seems odd to me also.
If it were mine, I'd also do a little masking/lightening to make the tree's trunk separate from the shadowed wheat.
And to me it looks stronger if you'd crop off about a third of the bottom to make it a panorama - give it a try and see what you think
the crop cut that I like is just a little lower than where the sunburst hits the right hand side.

David Stephens
11-22-2013, 04:10 PM
The sunburst is nice, the horizon stills looks odd.
Why would you shoot with a fisheye and then try to straighten it?
Isn't the point of having a fisheye lens to take unusual photo's?
Just wondering......

The horizon is correct, it does slope from left to down right.

You can use a fisheye to get an ultra-wide rectilinear view. This 15mm lens has a 180-degree diagonal field of view. It gives you an different perspective than you might get with something like a 24mm wide-angle. Here, I'm 3-ft. from the tree trunk and take in around 160-degree FoV after correction.

By the way, that wheat like grass is classic "short grass prairie". It's what the writer of the lyrics to "America" saw from the top of Pikes Peak when she turned away from the "purple mountains" to look at "amber waves of grain." This is where the "great plain" begins. Some say that she saw wheat, but those people have likely never been here. Wheat was not planted here in great quantities in the 1800 and it still isn't so much in Colorado. This is wild grass.

Here's an uncorrected fish-eye shot:

http://farm4.staticflickr.com/3734/9375672044_acf8c8625e.jpg (http://www.flickr.com/photos/dcstep/9375672044/)
Fisheye Shot (http://www.flickr.com/photos/dcstep/9375672044/) by dcstep (http://www.flickr.com/people/dcstep/), on Flickr

Same shot de-fished:

http://farm6.staticflickr.com/5524/9375674332_7590d25ece.jpg (http://www.flickr.com/photos/dcstep/9375674332/)
De-fished Image (http://www.flickr.com/photos/dcstep/9375674332/) by dcstep (http://www.flickr.com/people/dcstep/), on Flickr

David Stephens
11-22-2013, 04:12 PM
What do you guys do with ambiguous horizons? I look for other references, like the tree trunks in this image. Clearly, even though it looks right to me, it disturbs others.

David Stephens
11-22-2013, 04:15 PM
Hi David - I agree the sunburst is nice and so is golden tone of the wheat(?). The horizon seems to need some ccw rotation. There's something light blue in the wheat about halfway between the tree and the left edge that draws the eye. I'm also not sure what it is.

TFS,
Rachel

That is lens flare. I took it out before I printed, but left it in this internet version. Good eye. (It would have been even more annoying in my 50" print.)

Diane Miller
11-22-2013, 06:30 PM
Very nice image! I wouldn't have thought it was that wide angle. I find the tree intriguing and might want to see a little more of it. Love the starburst.

There is some hint here that the horizon is on a slope, but in a case like this where it could be taken as an oversight, I have no worries about correcting it. If a rotation made the tree look off, I'd go to Distort and pull down the LL corner. After all, I might have used a view camera without people worrying if I had altered the truth of a scene.

Andrew McLachlan
11-23-2013, 08:23 PM
Hi David, the Sigma fisheye does produce lovely sunstars. I have shot everything from landscapes to bullfrogs with it. In this photo I would like to see some separation from the tree and the field...the branches merging with the field grasses bothers me a little...a slightly lower perspective would have fixed this in the field...you could clone them out at this point though if you wished to. When I played around with correcting fisheye distortion with this lens I did notice 'smudging' of image details, particularly in the corners, but I have not tried DXO.

David Stephens
11-23-2013, 10:41 PM
Hi David, the Sigma fisheye does produce lovely sunstars. I have shot everything from landscapes to bullfrogs with it. In this photo I would like to see some separation from the tree and the field...the branches merging with the field grasses bothers me a little...a slightly lower perspective would have fixed this in the field...you could clone them out at this point though if you wished to. When I played around with correcting fisheye distortion with this lens I did notice 'smudging' of image details, particularly in the corners, but I have not tried DXO.

I traded to the Canon 15mm f/2.8 fish-eye soon after this shot and it did reduce smudging in the corners when de-fishing.

I printed this 50" on the long side and the smudging was not a real issue with this subject.