Become a fan of Slashdot on Facebook


Forgot your password?

Comment Additional methods (Score 1) 1

I would now narrow the middle section of the blue curve rather than increasing the slope. The settings for bright colors at the top right of the curves might not be so symmetric as I assumed above, since bright colors depend more on the transparency of the slides than on the faded dyes that count for dark colors.

User Journal

Journal Journal: My viXra articles

I posted two articles at the viXra archive for physics outsiders. Have a look if you will. I try to post first drafts of fresh thinking here, though. And look for my book "Hacking Physics". is my article "Neglect of General Covariance". is "Draw the metric!".

Michael J. Burns

User Journal

Journal Journal: The big bang is now.

Think about it in a careful way. Visualize a spacelike line, then extend it as a geodesic. Using a proper diagram of the universe, it is easy to show that this eventually intersects the big bang horizon. Don't be confused by convention; the Friedmann coordinates are very deceptive.

So shards of the big bang, expanding at light speed from a universal starting point in the past, are essentially contemporaneous with us.

User Journal

Journal Journal: Stephen Jay Gould understood natural selection on groups.

I read his essays on this point but did not understand until this year. He knew that natural selection on groups was a truism. And so he did not even argue at length for it, only focusing on the selection that acts on various sizes of groups, as opposed to accidents of history.

Comment So UFRaw does have a white level. (Score 1) 3

UFRaw does use a white level and balance that are set from the camera and the color matrix. In fact the photographic levels are truncated to the white level as given. So my expectation of being able to recover the highlights from an overexposed subject is frustrated. But just click the button to get the white balance from the camera. And set the camera's notion of the exposure by putting the flat truncation to the top of the graph using the exposure slider.

Comment ST65 overexposes. (Score 1) 3

I see that the ST65 overexposes in order to suppress noise. ISO 200 is actually ISO 80. This causes the high contrast naturally. I wonder if custom color curves in RawTherapee together with the low contrast setting on the ST65 can result in highlight recovery, while still taking advantage of the noise reduction from overexposure.

User Journal

Journal Journal: Calbrating digital cameras 3

My Samsung ST65 camera actually has a contrast control, and I have now realized that the proper setting for it is not zero. The default setting enhances contrast in the shadows and compresses the highlights. A -2 setting for contrast balanced by a +2 setting for saturation improves the appearance of the gray scale on a picture of the Color Checker 24 card. This might not be the final word - I will look at -1, +1 as well; but I have no desire to do post processing on photographs from this came

User Journal

Journal Journal: More on camera bit rates

For film cameras using the same film, the bit rate proportionality simplifies to the product of the aperture area and the frame area. Slower film has the higher bit rate. For digital cameras that use the same technology, the proportionality is to the product of the aperture area and the number of pixels. But smaller sensor areas can force you to take multiple exposures in order to complete the picture with the required signal to noise ratio.

Michael J. Burns

User Journal

Journal Journal: Natural selection on groups is a truism.

Study of natural selection on groups is the most thorough rejoinder to to the libertarian dogma. Natural selection on groups is actually a mathematical truism. And it has a proportionate practical effect whenever transactions between individuals are not zero sum. The prominent effect is to promote specialization of individuals. Witness all of the specialties in the groups called ecosystems. The deprecation of groups by promotion of the concept of individuals is mathematically only a false dic

User Journal

Journal Journal: Samsung Digital Camera Compared to my Yashica

I am very interested in the question of what kind of digital camera can match the quality of a 35mm film camera. In the context of the new high definition digital post processing, how many pictures with a standard information content can I take with a camera in one second of open shutter?

User Journal

Journal Journal: Cartesian and Hyperspherical Coordinates for the Universe

Cosmologists need to check their work by using different coordinates. The Friedmann coordinates conventionally used are rife with fictitious potentials which interact nonlinearly with real sources of gravity. It is Cartesian coordinates alone that have no such effects. And hyperspherical coordinates are still orthogonal everywhere, so they have no off-diagonal fictitious potentials.

User Journal

Journal Journal: Audio CD Quality and Fictitious Forces in Cosmology

The quality of CD player reproduction is on my mind today, as is the contribution of fictitious potentials to cosmology. Both questions are guarded (at sites like Wikipedia and arXiv) by the orthodox priesthoods that censor discussion for the sake, in the end, of their personal equanimity.

User Journal

Journal Journal: Plain mathematical error in a cosmological computation

I really think that this calculation by Dr. Castelvecchi of the magnification of the cosmic background radiation is spoiled by an artifact of Friedmann coordinates, that he takes as real instead of discounting it.

Slashdot Top Deals

"The hottest places in Hell are reserved for those who, in times of moral crisis, preserved their neutrality." -- Dante