immersion oil question

Do you have any microscopy questions, which you are afraid to ask? This is your place.
Post Reply
Message
Author
mintakax
Posts: 125
Joined: Mon Jul 29, 2019 12:06 am
Location: Boulder CO, USA

immersion oil question

#1 Post by mintakax » Sat Sep 07, 2019 12:24 am

I ask forgiveness io advance if this is a bit "over the top". I have a small pond aquarium and I have a procedure which, to my thinking, results in the least harm to the organisms I observe. I hope I'm not just fooling myself.

I use a well slide with a glass cover and after observing, I dunk the entire slide in the aquarium water until the cover slide floats off a bit. I lift it off with a pair of tweezers and rinse it in the aquarium, then toss it. I similarly rinse the slide, but re-use it.

I'm wondering if following the same procedure with a slide that had immersion oil (after being wiped off) on the cover would eventually foul up the aquarium water ? I know it will float on the surface, but the surface exchange with the air must be a pretty big deal.

Thanks,
Dan

User avatar
wporter
Posts: 252
Joined: Wed Oct 21, 2015 10:18 pm
Location: USA

Re: immersion oil question

#2 Post by wporter » Sat Sep 07, 2019 2:03 am

I would think that the oil, especially if it eventually spreads out to form a sheen or layer, would probably negatively impact the air-water gaseous exchange rate or process.

MicroBob
Posts: 1397
Joined: Sun Dec 25, 2016 9:11 am

Re: immersion oil question

#3 Post by MicroBob » Sat Sep 07, 2019 5:04 am

This is probably no design criteria for the formulation of immersion oil so I would be careful.
You might look for a clear natural oil of suitable refractive index instead. This oil might not be perfect optically and it is not tested for use on microscope objectives but this may not be a big problem.

Bob

User avatar
75RR
Posts: 6165
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona

Re: immersion oil question

#4 Post by 75RR » Sat Sep 07, 2019 5:35 am

One solution would be to not oil the condenser and to lift the cover slip off before dunking the slide.

As it is a well slide, that is where most of the animalcules will be.


Note: Higher magnification objectives have a shallower depth of field, they are not ideal for well slide use.
I lift it off with a pair of tweezers and rinse it in the aquarium, then toss it.
There is no need to toss cover slips after one use when observing pond water. I reuse them several times.


Have a look at Oliver's video. It does look a little stressful at times but it does have a happy ending

Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

Roldorf
Posts: 338
Joined: Tue Apr 23, 2019 6:58 pm
Location: Northern Germany

Re: immersion oil question

#5 Post by Roldorf » Sat Sep 07, 2019 1:05 pm

What do you expect to see from an aquarium with a 100x lens that can't be observed under a 60x? you wouldn't need to use oil at all.
Alan
Bresser Science Infinity 4x 10x 40x 60x 100x oil. Canon EOS 4000d
Optika SFX 90

Sauerkraut
Posts: 193
Joined: Tue Apr 16, 2019 2:07 am
Location: Oregon, USA

Re: immersion oil question

#6 Post by Sauerkraut » Sat Sep 07, 2019 5:04 pm

Perhaps instead of dunking the slide, you could get a squirt bottle that has a good water stream so the microbes could be jetted back into the tank with minimal oil contamination.

Something like this:

https://www.amazon.com/Economy-Bottle-S ... 0497&psc=1

mintakax
Posts: 125
Joined: Mon Jul 29, 2019 12:06 am
Location: Boulder CO, USA

Re: immersion oil question

#7 Post by mintakax » Sat Sep 07, 2019 7:14 pm

75RR wrote:
Sat Sep 07, 2019 5:35 am
One solution would be to not oil the condenser and to lift the cover slip off before dunking the slide.

As it is a well slide, that is where most of the animalcules will be.


Note: Higher magnification objectives have a shallower depth of field, they are not ideal for well slide use.
I lift it off with a pair of tweezers and rinse it in the aquarium, then toss it.
There is no need to toss cover slips after one use when observing pond water. I reuse them several times.


Have a look at Oliver's video. It does look a little stressful at times but it does have a happy ending

Thanks 75
Yikes on the video ! Resilient creatures they are. I think I'm going to give up on the 100x oil immersion, since I think the depth of field will be driving me nuts anyways.

mintakax
Posts: 125
Joined: Mon Jul 29, 2019 12:06 am
Location: Boulder CO, USA

Re: immersion oil question

#8 Post by mintakax » Sat Sep 07, 2019 7:18 pm

Roldorf wrote:
Sat Sep 07, 2019 1:05 pm
What do you expect to see from an aquarium with a 100x lens that can't be observed under a 60x? you wouldn't need to use oil at all.
I would certainly prefer 60x. I have10,20,40 and 100x DIC inserts in my turret but not 60x.

mintakax
Posts: 125
Joined: Mon Jul 29, 2019 12:06 am
Location: Boulder CO, USA

Re: immersion oil question

#9 Post by mintakax » Sat Sep 07, 2019 7:20 pm

Sauerkraut wrote:
Sat Sep 07, 2019 5:04 pm
Perhaps instead of dunking the slide, you could get a squirt bottle that has a good water stream so the microbes could be jetted back into the tank with minimal oil contamination.

Something like this:

https://www.amazon.com/Economy-Bottle-S ... 0497&psc=1
Thanks Heather-- I actually had considered just that.

mintakax
Posts: 125
Joined: Mon Jul 29, 2019 12:06 am
Location: Boulder CO, USA

Re: immersion oil question

#10 Post by mintakax » Sat Sep 07, 2019 7:20 pm

wporter wrote:
Sat Sep 07, 2019 2:03 am
I would think that the oil, especially if it eventually spreads out to form a sheen or layer, would probably negatively impact the air-water gaseous exchange rate or process.
Completely agree. Thanks.

Post Reply