Condenser settings?

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GaryB
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Post by GaryB »

The standard that has been around forever is that the light should be 10 inches away, this makes the light rays more or less parallel and the iris, a bit closer. There is no fixed iris position position.

dragonblade
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Post by dragonblade »

I tried to insert a cardboard iris within the microscope but there's barely any room above the built-in light source. It's way too tight and awkward.

By the way, the globe in my desktop lamp is 11W. Though you're recommending a 60w globe? 11 watt already seems super bright to me. Don't want to harm my eyes shining something excessively bright off a microscope mirror. Though I guess the objectives would reduce the intensity of that light as it passes through them?

Pau
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Post by Pau »

By the way, the globe in my desktop lamp is 11W. Though you're recommending a 60w globe?
What matters is the amount of light. 11W LED or fluorescent lamp roughly equals to 60W incandescent (a bit more with LED), could it be the discrepancy?
Pau

dragonblade
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Post by dragonblade »

Pau wrote: What matters is the amount of light. 11W LED or fluorescent lamp roughly equals to 60W incandescent (a bit more with LED), could it be the discrepancy?
Today, I bought a 60W LED globe from a supermarket. It is extremely bright. Hope it's not too bright but there's one way to find out.

rjlittlefield
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Post by rjlittlefield »

dragonblade wrote:Today, I bought a 60W LED globe from a supermarket.
I expect that's actually a "60W equivalent", with that rating based on the amount of light that it puts out. If so, then actual electrical power will be around 10W (9-11 depending on brand).

If that's not the case, and it really is 60W power consumed, then please provide more information about the bulb. Having such a bright light could be useful on occasion.

--Rik

ChrisR
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Post by ChrisR »

Some Work Lights are impressive, eg http://www.maxxima.com/products/product ... Light.html. The reflector shape & size is down to tradition, thought it serves as a heatsink. [edit]My rechargeable one is 20W, some are more. Not quite as bright as a 500W halogen - yet.
Last edited by ChrisR on Wed Mar 07, 2018 2:58 pm, edited 1 time in total.
Chris R

rjlittlefield
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Post by rjlittlefield »

ChrisR wrote:Not quite as bright as a 500W halogen - yet.
https://www.amazon.com/Halogen-Equivale ... B01KFVFQEI claims 100W input, 500W equivalent, 8000Lm.

--Rik

ChrisR
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Post by ChrisR »

That's mains - cheating!
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GrahamR
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Post by GrahamR »

I've just built two 100W LED strobes for my studio rig.

Image

They are mains powered though :lol:
Graham

dragonblade
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Post by dragonblade »

So I set up the desktop lamp (with the brand new LED globe) and the cardboard cutout iris at the recommended distance from my microscope with the mirror attached. Problem is I just cannot focus on the iris at all with the condenser wheel. So I doubled the distance of the lamp and cardboard iris from the microscope and that didn't make much of an improvement - the iris is still extremely soft and fuzzy while looking through the eyepiece. So then I tripled the distance - still no good. I moved the pair to the opposite end of the table and I still cannot focus on the iris.

By the way, I found it very difficult to get even illumination with the desktop lamp and 4x lens. I think I got it very close though. I think I'll go back to using the built-in light and try and guess the condenser setting by approximation. Sorry but I just cannot get my cutout field iris in focus - nowhere even close.

Edit: Ive just tried the new globe in the desktop lamp with the 40x objective and it is slightly dim. I lowered the condenser setting a little from the top and closed the condenser iris a little but the illumination is not particularly great.

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