Credit card re-issues continue

Apparently the problems at Citibank and other card houses are continuing like a boulder rolling downhill and causing a landslide.

A friend of mine with Bank of America was told late last week that a block of cards had been compromised and he’d have to get a new card.

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The two-channel that wouldn’t live

Something strange happened on the way to making a two-channel hologram Saturday…

I made a master hologram of a sand-dollar yesterday morning which came out nice and bright and clean and Susan suggested a two-channel, front and back of the same subject. Being in the groove I set about doing just that.

I exposed the left half of the plate, put the plate in my drying box while flipping the subject, got the plate back out and switched the mask so that the left half of the plate was covered and the right clear. Exposed, developed and found that the right channel was bright and clear and the left look dim and ugly. Examining the final bleached hologram lead me to believe that the plate had moved during the first exposure, mostly because I couldn’t find any other cause.

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Optic cleaning with collodion

This could also have been called optic destroying with collodion. You’ll see why in a bit.

Based on my first three attempts, I wouldn’t recommend bothering to use collodion with cheap mirrors.

Collodion is used for a number of applications, such as cleaning optics used in astronomy. It was recently mentioned on the Holography forum as a way to clean our precious mirrors and lenses.

Here’s the first mirror with a tape dam at an angle which attempts to show all the crud on the mirror. It’s not excessively dirty like you might get with optics used in astronomy but it’s dirty enough that it’s interfering with my reference beam light. The mirror is used to steer the light coming out of my spatial filter up to my collimating mirror and needs to be as clean as possible. Note that this was a cheap $1 mirror I bought at a local electronics shop.

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