f/ focal distance and trendmarks

[MADSH4RK]

Hi all! I want a new camera but I need to know what should I worry about when choosing one. For example, when looking to an f/ or to focal distance (mm) which values are the best? Lower or higher values? Lower or higher values range? And what about trends? If you had to put them from the best to the worst these ones:
Canon, Nikon, Fujifil, Olympus, Sony, Panasonic Lumia, Samsung?

I cant wait to start taking pictures for real

 

[unpopular]

132.6776mm is the ideal focal length when the diameter of the lens is 3x the apparent diameter of the sun when viewed from your position on earth, however, because the apparent size of the sun changes over the course of the day, the exact ideal focal length cannot be determined. This is the primary reason we have zoom lenses, to provide optical shielding from incoming solar radiation, regardless how large the sun appears at any given time of day.

 

[presspass]

Hi are you talking about a point and shoot camera? The focal distance and f/ refers to the lens and not the camera itself.

 

[KmH]

It's actually about making photos, not taking photos.

Just 20 threads down from yours is this thread - http://www.thephotoforum.com/forum/...-forum/267492-info-those-new-photography.html

That starts with this link:

Everything you need to know about buying a camera | The Verge

 

[unpopular]

LOL. i love how you guys just ignore me.

 

[TheBiles]

Money = quality, right? So longer focal lengths and faster apertures are obviously the best. Better start saving up for that 1200mm f/5.6L!

 

[tevo]

132.6776mm is the ideal focal length when the diameter of the lens is 3x the apparent diameter of the sun when viewed from your position on earth, however, because the apparent size of the sun changes over the course of the day, the exact ideal focal length cannot be determined. This is the primary reason we have zoom lenses, to provide optical shielding from incoming solar radiation, regardless how large the sun appears at any given time of day.

Come on, your math is completely wrong. A 132.6776mm lens with a diameter of the lens being 3x that of the viewed diameter of the sun from here? Are you insane? That would be a 146.98076mm lens with a maximum aperture of 2.75 depending on your relative position to the approximate equator of the sun versus your position on earth and the number of convex elements present in the lens. Furthermore when taking into account tangent properties of the diffraction of glass elements and the build quality of the lens it is entirely safe to assume that a 146.98076mm lens is entirely more sufficient and mathematically feasible than a 132mm, with rated bokeh levels at 7-9% variably.

 

[snowbear119 50]

132.6776mm is the ideal focal length when the diameter of the lens is 3x the apparent diameter of the sun when viewed from your position on earth, however, because the apparent size of the sun changes over the course of the day, the exact ideal focal length cannot be determined. This is the primary reason we have zoom lenses, to provide optical shielding from incoming solar radiation, regardless how large the sun appears at any given time of day.

Come on, your math is completely wrong. A 132.6776mm lens with a diameter of the lens being 3x that of the viewed diameter of the sun from here? Are you insane? That would be a 146.98076mm lens with a maximum aperture of 2.75 depending on your relative position to the approximate equator of the sun versus your position on earth and the number of convex elements present in the lens. Furthermore when taking into account tangent properties of the diffraction of glass elements and the build quality of the lens it is entirely safe to assume that a 146.98076mm lens is entirely more sufficient and mathematically feasible than a 132mm, with rated bokeh levels at 7-9% variably.

But is that assuming ∏=3.14159265359 or the more common ∏=3.14159?

 

[unpopular]

132.6776mm is the ideal focal length when the diameter of the lens is 3x the apparent diameter of the sun when viewed from your position on earth, however, because the apparent size of the sun changes over the course of the day, the exact ideal focal length cannot be determined. This is the primary reason we have zoom lenses, to provide optical shielding from incoming solar radiation, regardless how large the sun appears at any given time of day.

Come on, your math is completely wrong. A 132.6776mm lens with a diameter of the lens being 3x that of the viewed diameter of the sun from here? Are you insane? That would be a 146.98076mm lens with a maximum aperture of 2.75 depending on your relative position to the approximate equator of the sun versus your position on earth and the number of convex elements present in the lens. Furthermore when taking into account tangent properties of the diffraction of glass elements and the build quality of the lens it is entirely safe to assume that a 146.98076mm lens is entirely more sufficient and mathematically feasible than a 132mm, with rated bokeh levels at 7-9% variably.

You're totally working from an pre-Einstein point of view. According to the Einstein-Faraday coefficient, if the curvature of the entering face of the first convex element is less than 2% of the last exit convex lens curvature, provided it is aspherical, the solar equatorial diameter is compensated, permitting a significantly higher bokeh value than an Einstein-Faraday uncorrected objective, thus permitting significantly less solar radiation density at the film plane.

Snowbear is correct also, pi precision does account for some error in ideal focal length, however, less precision will have the opposite effect until about an error of 10%, where the error will begin to approach infinity at a rapid rate, leading to a risk of thermal energy concentrations that could eventually damage the shunt manifolds at the aperture flange.

 

[480sparky43 42]

Jeez, are you guys way off base. A 132.6776mm lens is useless because the filter threads rotate when focused. It's better to get the 148.91745mm....... not only does the filter thread not rotate, but you get a bayonet-mount petal hood! Besides, it uses standard 57.825mm filters.

 

[thetrue]

:lmao:

 

[unpopular]

Jeez, are you guys way off base. A 132.6776mm lens is useless because the filter threads rotate when focused. It's better to get the 148.91745mm....... not only does the filter thread not rotate, but you get a bayonet-mount petal hood! Besides, it uses standard 57.825" filters.

Clearly you are accustom to inferior glass which lacks a cross-coupled focus helical!!

 

[480sparky43 42]

Clearly you are accustom to inferior glass which lacks a cross-coupled focus helical!!

Only if you buy Versions I or II. Versions III and up corrected that problem.

 

[unpopular]

Exactly, it's a non issue! The 148.91745 "chimp" is outdated, at leads to aspherical elements responding non-laterally to the higgs field, resulting in, at best, a 0.2% shift in optical cohesion. Sure, it prevents thermal overload but the technique significantly degrades edge contrast just off the optical axis, running diagonally along the z-axis of the virtual image.

 

[tevo]

I think those of us that aren't brand new to the field know that a 142mm has a plastic bayonet mount which is reflective of the excellent build quality on the rest of the lens. I'm not sure how that can even be argued.