[caradoc]

The most dangerous thing we deal with in observational astronomy is a liquid helium dewar, which is pretty dangerous but not catastrophe dangerous.

That depends on the size of the Dewar.

I was in a building once that had a catastrophic dump of a rather sizable Dewar, and we had to evacuate. (liquid nitrogen, though, not helium.)

When sections of drywall and lath shatter like glass, that’s messy.

[caradoc]

I’m halfway there already. Goodwill has a stack of USB scanners on the Electronics shelf for about $10 each.

[caradoc]

I happen to know a PCB designer too. I’ve been meaning to make one of his Camera Axes anyhow.

My lightning trigger is based on his early circuit that later became the “Camera Axe.”

Works pretty darned well, if you ask me.

[caradoc]

I was told by a friend that my pictures aren’t loading unless she click’s through to the big ones–anyone else having difficulty seeing my posts?

Nope. The images appear in-line just fine for me.

[caradoc]

Also IIRC, I was against scanner “photography” before, but looking at Error’s image in the light of intended use has shifted my thinking some.

Take a look at this guy‘s work and see if your opinion shifts any further.

(The site appears to be down at the moment, but he uses a flatbed scanner with a lens to make a very large format camera…)

[caradoc]

He’s got instructions for building one, but states up front, “You should not build this because this flash will kill you. It really will.” Sounds like a challenge to me. 😉

Yep. New project.

I haven’t played with high voltage much since I built that infrared monocular back in high school. Burned a hole through the end of my finger with that one…

[caradoc]

Caradoc: Looks like posting is fixx0red for you?

Yep. Thanks for poking at them.

[caradoc]

They seem to have fixed my Fark issues right on time.

[caradoc]

All right… archive diving.

I won’t have time to shoot, so old stuff has to do.

[caradoc]

… having started a new job as of yesterday.

Yikes! A new job and a baby on the way. Sounds like it could be the recipe for a perfect storm of stress. Here’s wishing you smooth sailing on both counts.

Thanks… but “new job” in this case means spending a lot of time filling out a lot of paperwork to eliminate three layers of management and change the name appearing on my paychecks.

It’s a good thing.

[caradoc]

Yeah, this would be for next week – assuming I can’t get it fixed. I don’t have time to deal with “5 is right out,” having started a new job as of yesterday.

[caradoc]

Farkback = nonresponsive. I’m still unable to post comments in Fark threads at this time.

Can I impose on someone to post OBO for me again this week?

[caradoc]

I’ve noticed that over the past week or so, I hit “Submit” and the little wheel spins and spins before I eventually get a “connection timed out.” Click “back” once, hit “Submit” again, and it works in a blink.

It’s not every time, though.

[caradoc]

FSM doesn’t seem to be picking up the OBO entries. I’ll ping Schnee.

[caradoc]

1) Haze. I’ve taken comparison shots of sunny, hazy landscapes and saw a noticable improvement (not spectacular, but noticable) in long-distance clarity with the filter vs without.

Try it again with a polarizer instead of a UV filter – “haze” is typically caused by light reflecting from particulates, and can be dramatically cut with a polarizer. Also, you can give the polarizer a twist and vary the “haziness” if you choose.

2) Lens protection/cheap insurance. If nothing else, I’d rather scratch a sub-$100 filter (which I’ve done) than an obscenely-priced lens. I keep a UV filter on all my lenses for just this reason.

I find that a good lens hood provides better protection than a glass filter – moreso after having witnessed two different people scratching the hell out of their front elements by dropping the lens and shattering the filter. In both cases, a good lens hood would have dramatically reduced the likelihood of damage.

But now that this subject has come up, this is the second time this week I’ve read something about the uselessness or even disadvantage to using a UV filter. Can someone who feels that way expound on the topic a little? I understand the argument against putting a cheap filter in front of expensive glass, but is there more to it than that?

If you’ve looked over my work, you’ll note that I shoot an awful lot of very high contrast images, whether lightning or using strobes.

Putting a filter over the front of the lens makes for a lot of lens flares, “orbs,” “ghost lights,” and other artifacts resulting from light passing through the filter, reflecting from the front element of the lens, then reflecting again from the inside surface of the filter. There are some filters that are coated to reduce that effect, but none of them that I’ve tried have eliminated the effect.

[Author]

Posts