I just made a contact print in my darkroom. Interesting to see how much I remember from however long ago it was (15 or more years?).
I swept it out today, cleaned off the counter on what will be the wet side, fished out the trays and tongs I got through FreeCycle ages ago, hooked up the timers, mounted the safelight . . . I have a timer that seems pretty over-the-top but is really quite handy. The enlarger and safelight plug into it and you can switch between the two as needed, but when you use the footswitch (!) the safelight goes off, and the enlarger is turned on for a timed exposure. Very elegant, as far as I am concerned.
Of course, I have no idea how long to expose this out of date RC paper I have 500 sheets of, so I’m going to have to wait until I can get some paper chemistry before I have any idea how successful I was.
The enlarger can make a 16×20 print at full extension, more than I expect I’ll need, though the temptation to make a print that size is something I won’t even try to resist if I can afford the paper.
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> At $40 for the device, if these all get used just once more, it paid for itself.
An excellent return on investment!
I don’t use too many batteries, but we haven’t got kids with battery-powered toys. Still, I’m interested. I may end up with a portable guitar amp sooner or later, and they eat batteries.
If we can figure out how to solar power the thing, it’ll be even cooler, though the ROI on the solar cells will be patheticially long.
I owned an Alkaline battery recharger a long time ago… Years before Rayovac’s version. Frankly, I think it’s a complete waste of money. The charge it gives is completely superficial, and in my experience doesn’t last 10% as long as a new battery. Of course they say you should charge your just slightly used batteries frequently, but that’s incredibly impractical. If you want to save money, or the environment, I say stick with standard rechargeables, as trying to recharge Alkalines give you the worst of both worlds.
Hmm, time will tell. I bought mine based on the writeup on Kevin Kelly’s “Cool Tools” area. if it’s as bad as you say, I won’t be impressed, but if anyone else has encountered the same issue, they’ve not mentioned it to him.
And as you say, you bought one “a long time ago.” Things might have gotten better.
> Things might have gotten better.
This would only be possible if they changed the basic, non-reversible, chemistry of the alkaline cell.
Alkaline “refreshers” can be just barely worth using for some applications, if you’re an extreme penny-pincher and do not value your time very highly. Even the ones that you have to use with special variant-chemistry alkalines aren’t much good, though, and the ones that claim to “charge” standard alkalines are worse.
>But to cut down the amount of hazardous waste by 80% or so is still a clear win.
More like postpone.
If I use one 5 times, that’s 4 I didn’t have to buy and throw away. 4/5 = 80%. If, as seems likely, they don’t last as long recharged, maybe I only avoid buying 2 or 3, that’s still a savings on raw materials, on hazardous waste disposal, etc.
The chemistry involved in alkalines isn’t non-reversible. Battery chemistries are almost always reversible unless there’s a loss of material.
Even the ones that you have to use with special variant-chemistry alkalines aren’t much good, though
Not in my experience. They’re fine. I used rechargeable alkalines all the time for my old Gameboy Advance, since NiMHs had too low a voltage (and a different discharge curve) to have the LED correctly indicate state of battery charge. I also used them in low-drain devices, like remotes, etc., since alkalines actually have one of the highest energy densities of any battery other than lithium ion (their internal resistance is just too high for high-drain devices). At low drain, their energy capacity is something like 3-4000 mAh.
Read the writeup linked above – the problem with alkalines are the thin battery walls. Heat and gas buildup (pressure) blow them up. The rechargeables use exactly the same chemistry, yet with a thicker wall to allow for recharging. They end up with slightly less power density overall (due to the size constraint), but it’s still fine.
The “battery extender” here just charges them much more gently (pulse charging) to make sure the heat/pressure which is produced doesn’t burst the battery. The batteries eventually do usually leak, at which point you throw them away.
> The chemistry involved in alkalines isn’t non-reversible.
No, really, it is :-). Alkaline batteries, like carbon-zincs, are primary cells. You cannot charge them by applying power to them.
Yes, technically, the zinc hydroxide and manganese trioxide in a flat alkaline could be reacted back into metallic zinc and manganese dioxide and the battery reaction could run again. You can’t do that while the reagents are still inside the battery, though, without the help of magic nanobots. Just pushing electricity backwards through the battery will not do it; you’d have to pull the battery apart, chemically separate the components and redox them back into their original forms.
This is basically what happens in places that recycle old alkaline batteries.
All these “chargers” do, in contrast, is stir the inside of the battery up a bit, to allow the reagents to react a bit more fully.
Oh, yeah – actual written-on-the-pack “rechargeable alkalines” are indeed at least somewhat different, so they can be “refreshed” more profitably. It’s up to you to decide whether this is worth the time and extra initial purchase price.
Note that it’s now Now that it’s possible to buy several brands of NiMH battery with very low self-discharge (the “pre-charged” kind that you don’t have to charge before using them for the first time, which don’t go flat rapidly on the shelf), I think you really might as well use those rather than try to charge the unchargeable. NiMH cells have always been much cheaper overall than any kind of “rechargeable” alkaline.
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