Author: DB

  • Focus at infinity and beyond

    Question:
    I have long been interested in having a go at astrophotography and found the comments made by Tom Ormerod (AP 7 August) very informative.

    However, his statement that it can be really tricky to focus manually on the stars completely threw me. Wouldn’t it just be a case of focusing on infinity, or am missing something here? / David Richards

    Technical Editor Andy Westlake replies: Yes, it’s just a case of focusing on infinity. But the question is how do you accurately focus on infinity, especially in the dark? It isn’t remotely easy, because barely any lenses have a hard stop at the end of their focus travel any more, let alone an accurate one. Then if you do focus on infinity, how do you make sure the lens stays there? Even a slight nudge of the focus ring will throw the stars out of focus. Also most lenses for mirrorless cameras are focus-by-wire, and tend to reset the focus position when you turn the camera on or off. Various solutions to this problem have been developed. The Samyang AF 24mm F1.8 FE, for example, has a function specially designed for astrophotography that allows you to accurately calibrate its infinity focus position and then set the lens there by pressing a button on the barrel. Certain Irix manual-focus lenses have a calibrated click-stop at the infinity position, along with a locking focus ring.

    Meanwhile, Olympus users who are lucky enough to own either the OM-D E-M1X or the OM-D E-M1 Mark Ill benefit from a unique ‘Starry Sky AF’ mode, which remarkably can autofocus on stars consistently accurately.

    Amateur Photographer
    2 October 2021
    Letters page
    Page 20

  • What The Dickens

    The Merry Wives of Windsor is the first recorded use of the phrase ‘What the dickens…?’ Plainly it does not refer to Charles Dickens because it predates his birth by several hundred years. Some phrase finders suggest that ‘dickens’ is used by Shakespeare to refer to the devil in a new way that is a twist on similar words.

    But it is not sure, and it could be a twist on the nickname for Richard. Or it could be something that Shakespeare pulled out of the air. After all, he invented more than one thousand new words and brought them into the English language.

    Here is scene II of The Merry Wives of Windsor, with the phrase highlighted.

    SCENE II. A street.

    Enter MISTRESS PAGE and ROBIN
    MISTRESS PAGE
    Nay, keep your way, little gallant; you were wont to
    be a follower, but now you are a leader. Whether
    had you rather lead mine eyes, or eye your master’s heels?
    ROBIN
    I had rather, forsooth, go before you like a man
    than follow him like a dwarf.
    MISTRESS PAGE
    O, you are a flattering boy: now I see you’ll be a courtier.
    Enter FORD

    FORD
    Well met, Mistress Page. Whither go you?
    MISTRESS PAGE
    Truly, sir, to see your wife. Is she at home?
    FORD
    Ay; and as idle as she may hang together, for want
    of company. I think, if your husbands were dead,
    you two would marry.
    MISTRESS PAGE
    Be sure of that,–two other husbands.
    FORD
    Where had you this pretty weather-cock?
    MISTRESS PAGE
    I cannot tell what the dickens his name is my
    husband had him of. What do you call your knight’s
    name, sirrah?
    ROBIN
    Sir John Falstaff.
    FORD
    Sir John Falstaff!
    MISTRESS PAGE
    He, he; I can never hit on’s name. There is such a
    league between my good man and he! Is your wife at
    home indeed?
    FORD
    Indeed she is.
    MISTRESS PAGE
    By your leave, sir: I am sick till I see her.
    Exeunt MISTRESS PAGE and ROBIN

  • Only Fools and Horses

    The phrase ‘Only Fools and Horses’ from the TV series of that name is based on a 19th-century American vaudeville saying that ‘only fools and horses work for a living’.

  • Selective Mutism

    Selective mutism is an anxiety disorder in which a person who is otherwise capable of speech becomes unable to speak when exposed to specific situations, specific places, or to specific people, one or multiple of which serving as triggers. Selective mutism usually co-exists with social anxiety disorder.

    People with selective mutism stay silent even when the consequences of their silence include shame, social ostracism, or punishment.

  • Roll Over Beethoven

    Beethoven’ unfinished Tenth Symphony has been completed – by an artificial intelligence programme. Researchers “trained” the AI by feeding it the work of composers Beethoven listened to, along with his own work. The result was so convincing, scholars could not tell where the original phrases ended and the new ones began.

    Reported in THE WEEK 9 October 2021

  • Queen Termites

    She’s huge, many, many times bigger than all the other termites. She is fed constantly and she is an egg factory, pushing out three eggs a second for half of the fifty years of her life.

    So three a second for twenty five years is more than two billion eggs. That’s 2,365,200,000 eggs.