Archs Hurt In Figure Skates

cards - cards - cards - GREETINGS - I wish - I wish

Best wishes for a peaceful Christmas

and a 2011 full of pleasant news.

How Do You Get Rid Of Ringworm On A New Tatto

creativity and experimentation.

On ClickBlog I found a picture of Chris Kotsiopoulos to me intrigued:

42 photos with Canon 550D, 15mm lens. F / 4, shutter 3.2 sec. at 100ISO.

Amateur Astronomer - see his photos on Flickr - and apparently attracted by all that is tied to natural events, in a particularly good night last June, has seen fit to devote himself to photography of lightning in immediate vicinity of the stadium in Athens. Nothing extraordinary one could argue, were it not that put his camera on the stand he took over half an hour 51 pictures (he also appears in one), and 42 of them (the remaining 9 were discarded for because of light exposure) made a sandwich, getting a really great result.
It seems that the biggest lightning, which seems almost flat on his head, and fell only a few hundred yards away. Apart from the data shown in the photo, are not provided more details about the shooting or the subsequent processing: watching the water falling from the upper deck at the top, you'd think that for one of the photos have also used a bit of flash , since the long exposure time did not allow to freeze the large drops that fall (unless it is due to the strong intensity of the flash closer) may also have required a good job in preparation, data the long sequence of images to overlap, and the need to balance the weight of each photo on the overall result.
But the aspect that has convinced me more than anyone else in deciding to offer this image is not purely technical; looking at his other photos on Flickr I could sense a gradual approach to photography: 's use a compact Canon A75 to capture a snowfall in Athens in 2008, then the Canon 300D camera attached to a telescope photograph the moon, until the last experience with the new 550D, which is exploring the field courses rarely even advanced amateurs and professionals. Transpires a progressive involvement, the fact that it does not stop to buy a new camera and a nice goal, but that is taking him to study and experiment with creative new ways. Bravo Chris! We look forward to your next picture.

Confirmation Letter Daughter

Approach to Macro - up lenses

The term macro is often used improperly, because we can talk about only if the macro magnification ratio is at least 1:1 , ie when the image reproduced on the film or sensor is the same size as subject. If the magnification ratio is less than 1, it is more correct to talk about photography at a distance close, otherwise defined as "Close-Up."
A first step for the latter discipline is to use additional lenses: These lenses are positive by 1 or more diopters, which can easily be fitted over the lens through the threads available for use filters. The benefits of additional lenses are not limited to practical use, it is also cheaper than other solutions and not have the need to vary the exposure.

The disadvantages stem from the fact that they can not be optimized with respect to the objective on which are mounted, involving lower quality (especially at the edges), which obviously depends on the quality of the lens, and usually increases with the number of diopters or more if we use the lenses together.

to limit the decline in quality due to aberrations, some manufacturers adopt a scheme to two elements (achromatic doublet), or three elements in two groups on the internet I have read very positive opinions for some of these lenses
- eg.: those Canon 250D (+4) and 500D (+2) - only problem is that the cost goes up to 80-100 € (52-58mm diameters.), compared to 18-25 € a lens Hoya, B + W Kenko or a single element.

The lens has the additional effect of reducing the focal lens is mounted on which, however, given that the draft (distance from the mouth of the lens mount from the focal plane) remains unchanged, the target group + lens able to focus at a distance less than the maximum allowed by one goal, making it possible to photograph the subject more closely.
Let's see what results you get with a 50-200 zoom lens and three 1, 2 and 3 diopter that I own (see photo at the beginning of post). In the tests I photographed an old bill from £ 1,000 well-preserved; to have a meter By comparison I would remind you that the size of the note are 11.4 x 6.1 cm.:

- Let's start with the smallest focal zoom, to 50 mm.

Magnification approximately 0.05











Magnification approximately 0.1.

Magnification about 0.15.

Magnification approximately 0.21

- continue with the results of the central focal zoom, the 100mm.

Magnification approximately 0.1

Magnification approximately 0.21.

Magnification approximately 0.32.

Magnification approximately 0.43.

- And finally we see the results on the focal length longer than 200mm.

Magnification approximately 0.22.

Magnification approximately 0.47

Magnification approximately 0.71.

Magnification approximately 0.96.








My preference towards the 50-200 zoom lens comes from the fact that the additional have a more pronounced effect on the lenses and they allow to stay further away from the subject, which, in many cases is an important advantage (such as when photographing animals).
As a last notation, remember that the use of an additional lens, due to the change in focus on introducing, on the one hand you get closer to the subject, the other will not allow focus to infinity, appearance little significance if we consider the situations in which we will make use of the lenses.


To conclude: even when you do not feel particularly attracted by the close-up photography, I think worthwhile to invest a few Euros on an additional lens, I am sure that after some testing you will discover a world of interesting and varied and you will not regret buying: look at the picture on the side and see if you guess what I photographed ...

For those who like to experiment with the calculations, below some guidelines and formulas that I found on the Internet:

The ability of slow to converge / diverge light rays is expressed in diopters, representing the reciprocal of the focal length in meters (also applies to the objectives). The power in diopters D of an additional lens with a focal length F (in millimeters), is determined by the following formula:

= D 1000: F
For example, if an additional lens focal length is 200 mm, its power is:
1000: 200 = 5 diopters

To determine the focal length in millimeters, of course, just reverse the formula:

F = 1000: D
For example, if the power of an additional lens is 2 diopters, its focal:

1000: 2 = 500 mm.

Using the number of diopters D and the focal length of F , in meters, we can calculate the focal length Fc + objective lens system resulting from the following formula:
Fc = F / 1 + DF

Starting instead from the lens focal additional ( F lens ) , and the objective F , the focal length Fc lens of the complex target can be calculated as follows:
Fc = (F lens x F) / (F slow + F)
(with focal always expressed in millimeters)

If we want to know what the minimum focus distance of a target by using an additional lens, just apply the following formula:
d min = (F lens xd ob) / (F + lens d ob)

where: d min = Minimum distance focus of the whole "objective + lens".
ob d = minimum distance of focus of the lens without additional lenses.
lens F = Focal length of the additional lens.

(also In this case, all measures should be in millimeters).