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Fun with the Leica SL (digital)

vieri

Well-known member
Tre Cime di Lavaredo, Italy

A different view of Tre Cime di Lavaredo at sunset, in the amazing Dolomites mountain range in Italy. This is a 24 seconds exposure taken with Leica SL, Laowa 12mm Zero-D and Formatt Hitech Filters Firecrest Ultra.



Thank you for viewing, best regards

Vieri
 

vieri

Well-known member
Sunset at Urro del Manzano, Cantabria (Spain)

Urro del Manzano at Sunset, in Cantabria (Spain). This is a 60 second long exposure taken with Leica SL, Leica Vario-Elmarit-SL 24-90mm and Formatt-Hitech Firecrest filters.



Thank you for viewing, best regards

Vieri
 

vieri

Well-known member
San Giovanni in Ranui, Dolomites

When you arrive to the tiny church of San Giovanni in Ranui, on the Dolomites (Italy), you are faced with one of these classic views that have been photographed to death but which timeless beauty is just undeniable. On a beautiful May sunset, I forewent the sunset colours and portrayed it in a dramatic black & white, with the help of an amazing sky and of a 2-minutes long exposure. With Leica SL, Leica Vario-Elmarit-SL 24-90mm and the incredible Formatt-Hitech Firecrest Ultra filters.



Thank you for viewing, best regards

Vieri
 

Robert Campbell

Active member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

Urro del Manzano at Sunset, in Cantabria (Spain). This is a 60 second long exposure taken with Leica SL, Leica Vario-Elmarit-SL 24-90mm and Formatt-Hitech Firecrest filters.

Vieri, it took me a while to work out what puzzled me about this picture. You don't say what focal length you used, but you generally favour (very) wide angles.

The horizon is not just level, but perfectly straight. In reality (in a very wide angle view) would we not be able to see the slight curvature of the earth's surface? I realise this is an odd statement, as if I was expecting some barrel distortion; that's not what I have in mind, just that the horizon seems too straight.
 

pegelli

Well-known member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

The horizon is not just level, but perfectly straight. In reality (in a very wide angle view) would we not be able to see the slight curvature of the earth's surface? I realise this is an odd statement, as if I was expecting some barrel distortion; that's not what I have in mind, just that the horizon seems too straight.
The exif says the shot is taken at 28 mm, so not super wide.

Secondly I think the horizon looking out over the sea is always straight, even with the widest angle lens, the points at which we see the horizon are all at exactly the same distance from where we stand, and therefore by definition perfectly horizontal and straight.
 

vieri

Well-known member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

Vieri, it took me a while to work out what puzzled me about this picture. You don't say what focal length you used, but you generally favour (very) wide angles.

The horizon is not just level, but perfectly straight. In reality (in a very wide angle view) would we not be able to see the slight curvature of the earth's surface? I realise this is an odd statement, as if I was expecting some barrel distortion; that's not what I have in mind, just that the horizon seems too straight.
The exif says the shot is taken at 28 mm, so not super wide.

Secondly I think the horizon looking out over the sea is always straight, even with the widest angle lens, the points at which we see the horizon are all at exactly the same distance from where we stand, and therefore by definition perfectly horizontal and straight.
Robert, I think pegelli's explanation makes sense - possibly, what you always thought it's the Earth curvature in other photographs was, in fact, some lens' barrel distortion? :)

Best regards,

Vieri
 

Robert Campbell

Active member
The exif says the shot is taken at 28 mm, so not super wide.

Secondly I think the horizon looking out over the sea is always straight, even with the widest angle lens, the points at which we see the horizon are all at exactly the same distance from where we stand, and therefore by definition perfectly horizontal and straight.
Robert, I think pegelli's explanation makes sense - possibly, what you always thought it's the Earth curvature in other photographs was, in fact, some lens' barrel distortion? :)
Thanks both for your comments.

1. pegelli: I'm not sure about this. I'm sure that if you have a wide enough view you can see the curvature of the earth, though it is very slight. You do often need to be high up to experience properly.

2. Vieri: I wasn't thinking about other photos, rather (as above) what I'd experienced previously.

I'd not noticed this absolutely level and straight horizon in other photos of yours; I suspect that may be because you generally have something at the edge blocking one end of the horizon.

3. I was also thinking of entasis. This is a feature of Greek architecture, where vertical columns bulge very slightly in the middle. This isn't apparent to the naked eye, but makes their proportions appear "more natural"; it's a sort of visual illusion. The Parthenon uses entasis in its columns.

There is a similar architectural "trick" on the horizontal. The Library of Celsus at Ephesus was built on a very constricted site, and to make it look bigger it is slightly bowed in the middle, and the outer columns are slightly shorter than the central ones. The Parthenon also has this, as apparently does the radiator grille of older Rolls-Royces; alas, I'm not in a position to confirm this.

I'm not criticising your image, Vieri; as usual, it is technically perfect. But because of this, in relation to the horizon, it appears to me to be not quite right. I'm rather suggesting that there should be a very slight curve to the horizon, concave downwards, to make it appear straight.
 

MGrayson

Subscriber and Workshop Member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

The exif says the shot is taken at 28 mm, so not super wide.

Secondly I think the horizon looking out over the sea is always straight, even with the widest angle lens, the points at which we see the horizon are all at exactly the same distance from where we stand, and therefore by definition perfectly horizontal and straight.
\begin :lecture:
In a cylindrical projection, this is true. But projecting a circle onto a plane makes a conic section. In this case, a hyperbola - a VERY flat hyperbola, but one nonetheless.

Another way to think of it - If you were at an altitude of 100,000 miles, the earth's horizon would certainly not look straight, so why would it at an altitude of 5 feet?

To be precise, if the entire horizon is visible to the plane, then you see an ellipse - otherwise a hyperbola. Circles and parabolas require infinitely precise positioning.
\end :lecture:

Matt
 

pegelli

Well-known member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

\begin :lecture:
In a cylindrical projection, this is true. But projecting a circle onto a plane makes a conic section. In this case, it is a hyperbola - a VERY flat hyperbola, but one nonetheless.

Another way to think of it - If you were at an altitude of 100,000 miles, the earth's horizon would certainly not look straight, so why would it at an altitude of 5 feet?

To be precise, if the entire horizon is visible to the plane, then you see an ellipse - otherwise a hyperbola. Circles and parabolas require very exact positioning.
\end :lecture:

Matt
You might be right, but I have difficulty understanding why my theory doesn't work.

Imagine yourself standing at the shoreline, with your eyes about 6 feet above ground.
From that point you would have a 180 degree view of the horizon, and if the earth (or the water surface) were a perfect sphere you would be able to look the same distance, left, center and right, and you would see the horizon at all these points at the same height. I think connecting these points would give you a straight line.

In other words, your eyes are the exact center of a circle, which lies in the plane of your eyes to the horizon, hence the inside of that circle looks like a straight line.

Any real mathematical help to debunk or confirm my theory is appreciated :salute:
 

vieri

Well-known member
...

2. Vieri: I wasn't thinking about other photos, rather (as above) what I'd experienced previously.
You mean experienced in the real world? Sorry - I thought you meant experienced previously looking at photos;

I'd not noticed this absolutely level and straight horizon in other photos of yours; I suspect that may be because you generally have something at the edge blocking one end of the horizon.

...
Now I am confused :D You said you weren't thinking about other photos, now you talk about comparisons with my other photos...

Anyway, your point is well taken :)

...

3. I was also thinking of entasis. This is a feature of Greek architecture, where vertical columns bulge very slightly in the middle. This isn't apparent to the naked eye, but makes their proportions appear "more natural"; it's a sort of visual illusion. The Parthenon uses entasis in its columns.

There is a similar architectural "trick" on the horizontal. The Library of Celsus at Ephesus was built on a very constricted site, and to make it look bigger it is slightly bowed in the middle, and the outer columns are slightly shorter than the central ones. The Parthenon also has this, as apparently does the radiator grille of older Rolls-Royces; alas, I'm not in a position to confirm this.

I'm not criticising your image, Vieri; as usual, it is technically perfect. But because of this, in relation to the horizon, it appears to me to be not quite right. I'm rather suggesting that there should be a very slight curve to the horizon, concave downwards, to make it appear straight.
This makes a lot of sense - it has been a long time since I studied classic architecture, and while I find myself applying these principles without thinking when shooting architecture, where I never go for perfectly straight verticals even if I could, always leaving an extremely subtle "converging" feel to them because it just "looks right", I never thought about using this trick for horizon on the sea. I'll think about it, but - at the moment - "adding it in" is something that does not feel quite right... for some reason, I would feel OK with not correcting it were it present, but adding it in goes a bit against my approach. Again, thank you for your comment, very stimulating - I will definitely think about it.

Best regards,

Vieri
 

MGrayson

Subscriber and Workshop Member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

You might be right, but I have difficulty understanding why my theory doesn't work.

Imagine yourself standing at the shoreline, with your eyes about 6 feet above ground.
From that point you would have a 180 degree view of the horizon, and if the earth (or the water surface) were a perfect sphere you would be able to look the same distance, left, center and right, and you would see the horizon at all these points at the same height. I think connecting these points would give you a straight line.

In other words, your eyes are the exact center of a circle, which lies in the plane of your eyes to the horizon, hence the inside of that circle looks like a straight line.

Any real mathematical help to debunk or confirm my theory is appreciated :salute:
The problem is that the circle is NOT at your eye level, but somewhat below it. I will calculate the exact distance, but it is obviously at least the height of your eyes above the ground. Mind you, the effect I'm talking about is probably so small that I doubt any existing camera could detect it. I was being pedantic.

If the film were cylindrical with some nodal point at the center, then your argument would be exactly correct. Since film is a plane, there is a slight distortion.

Here is the actual math. Assume a perfectly spherical Earth. Let r=4000 miles be the radius of the earth and h=5 feet the height of the camera above the surface. The height of the horizon circle is exactly h*r/(r+h) below the ground, making it h+h*r/(r+h) below the camera. Given how much bigger r is than h, this is VERY closely approximated by 2*h, or about 10 feet (the second term in the expansion is about 1/80,000 of an inch). The horizon circle has radius very closely approximated by Sqrt[2*r*h], or about 2.75 miles. So our cone has slope 10/(2.75*5280), or about 0.0007.

The hyperbola on the sensor plane using, say, a 25 mm focal length lens, gives the curve -.0007*Sqrt[625+x^2], where x is the number of mm off-axis. This drops from 17 microns below center to 21 microns by the edge for a drop of 4 microns. So about 1 pixel.

Now if you were on top of a mile high mountain looking out to sea, the calculation puts the horizon over half a mm below dead center, and dropping another 0.12 mm by the edge. With 5 micron pixels, this is 24 pixels. The horizon would appear curved.

Matt
 
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pegelli

Well-known member
Re: Sunset at Urro del Manzano, Cantabria (Spain)

The problem is that the circle is NOT at your eye level, but somewhat below it. I will calculate the exact distance, but it is obviously at least the height of your eyes above the ground. Mind you, the effect I'm talking about is probably so small that I doubt any existing camera could detect it. I was being pedantic.
Thanks Matt, and I don't mind you being pedantic and after your explanation I think I understand it better. :thumbup:

So from the top of the table mountain in South Africa you should be able to spot the curvature of the earth. Maybe a reason to go there and see if I can see it :bugeyes:
 

Robert Campbell

Active member
...
This makes a lot of sense - it has been a long time since I studied classic architecture, and while I find myself applying these principles without thinking when shooting architecture, where I never go for perfectly straight verticals even if I could, always leaving an extremely subtle "converging" feel to them because it just "looks right", I never thought about using this trick for horizon on the sea. I'll think about it, but - at the moment - "adding it in" is something that does not feel quite right... for some reason, I would feel OK with not correcting it were it present, but adding it in goes a bit against my approach. Again, thank you for your comment, very stimulating - I will definitely think about it.
My apologies for any confusion, Vieri; and thanks for responding to this rather arcane discussion.

Perhaps I'm just particularly sensitive to level horizons (and plumb verticals). My mother had a strange and rather embarrassing habit when out visiting, or even going to a restaurant, of looking at the pictures on the walls, deciding they weren't level, and then correcting them. I seem to have inherited this; I have to make a real effort not to change other people's pictures ;)

Your point about verticals is interesting. I often find that in architectural photos of tallish buildings, say a cathedral, and ones taken with a tilt/shift lens, that the upper part "dominates" as if it is leaning out towards me. I find this unsettling. I know we are supposed to have the verticals of buildings exactly plumb, but for me this appearance is "wrong". I think, as you say, that the upper parts should lead ever so slightly backwards (that is, the verticals should slightly converge) to give a "natural" appearance.
 

vieri

Well-known member
Triangles at Playa de Mexota, Spain

At Playa de Mexota, Asturias (Spain), you'll find yourself facing a sail-shaped sea stack towering in the Atlantic ocean. After climbing on the rocks facing the stack and finding a composition, it was just a matter of waiting for the sunset...*This is a 36 seconds exposures, with the help of Leica SL, Voigtlander 15mm Super Wide-Heliar and my beloved Formatt-Hitech Firecrest filters.



Thank you for viewing, best regards

Vieri
 

vieri

Well-known member
San Giovanni in Ranui, Dolomites - in colour

This is again the famous church of San Giovanni in Ranui at sunset, on the Dolomites (Italy). This is a one-minute long exposure and this time, after posting the B&W version a few days ago, I present it to you in colour. With Leica SL, Leica Vario-Elmarit-SL 24-90mm and the incredible Formatt-Hitech Firecrest Ultra filters.



Thank you for viewing, best regards

Vieri
 

Robert Campbell

Active member
Re: San Giovanni in Ranui, Dolomites

When you arrive to the tiny church of San Giovanni in Ranui, on the Dolomites (Italy), you are faced with one of these classic views that have been photographed to death but which timeless beauty is just undeniable. On a beautiful May sunset, I forewent the sunset colours and portrayed it in a dramatic black & white, with the help of an amazing sky and of a 2-minutes long exposure. With Leica SL, Leica Vario-Elmarit-SL 24-90mm and the incredible Formatt-Hitech Firecrest Ultra filters.



Thank you for viewing, best regards

Vieri
I prefer this b/w version to the one in colour, though I'd crop the sky a bit.
 

vieri

Well-known member
Land's End sunset

Land's End, in Cornwall, is a truly magical place. Once you get past the (terrible!) amusement park-like thing close to the parking lot and start wandering along the cliffs, you realise that west of you there is nothing but ocean until the American continent's shores. Enys Dodnan Arch looks and feels like a door open towards the New World. Leica SL, Leica Super-Vario-Elmar-SL 16-35mm and the great Formatt-Hitech Firecrest Ultra filters.



Thank you for viewing, best regards

Vieri
 
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