Hello,
We haven't had much snow here in western NY yet this season, but a few days ago we had a bit and it was cold enough to capture these.
I'm still using an old 1942 AO Spencer microscope with a 4x LOMO objective.
Does anyone know if AO Spencer ever made a dark field condenser for this vintage of scope? I'd like to improve the dark field images I capture. They need some work.
Thanks
Nick L
here's a couple of more images
I've made some improvements in the way I take dark field shots.
Now all I need is some more snow!
Thanks for taking a look
-Nick
First of the season
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First of the season
Last edited by nlamendo on Wed Feb 01, 2012 6:02 pm, edited 1 time in total.
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Those are awesome shots. Could you please elaborate a bit on how you got them, equipmenet etc.? I may get some snow this weekend here in the NW and now after seeing your pictures I'd really like to try taking a few myself (that is if we don't get rained on...). What were weather conditions like too?
David
David
Hi Dave,
I'm using an old collage microscope (1942 AO Spenser) I've replaced one of the objectives with a 4x LOMO, .12 NA plan achromat. I don't use the eyepiece on the microscope, that is removed and the my camera is coupled to the microscope where the eyepiece would be. The microscope is left out in an unheated garage. I let the snow fall on a piece of black velvet, and when I find a suitable snow crystal I transfer it to a cold glass slide using very small paint brush and quickly put it under the microscope, focus and snap a picture. The lighting takes some trial and error (at least it did for me). It all works best when the temps are in the teens to low 20's (degrees F).
I'm using a white LED flash light as a cold light source, this shines up thorough the condenser, back lighting the snow crystals. Colored gels are used for the bright field shots. I'm using a black obstruction in the middle of the condenser for the black field illumination shots. They need some work, I'm not happy with the results. My set up also doesn't work very well for large snow crystals, the magnification is too high, and I can't fill the entire frame in my camera. I can only image in the center of the frame. I haven't figured out how to use more of the image frame.
I hope this helps you, It's a lot a fun to do. good luck.
-Nick
I'm using an old collage microscope (1942 AO Spenser) I've replaced one of the objectives with a 4x LOMO, .12 NA plan achromat. I don't use the eyepiece on the microscope, that is removed and the my camera is coupled to the microscope where the eyepiece would be. The microscope is left out in an unheated garage. I let the snow fall on a piece of black velvet, and when I find a suitable snow crystal I transfer it to a cold glass slide using very small paint brush and quickly put it under the microscope, focus and snap a picture. The lighting takes some trial and error (at least it did for me). It all works best when the temps are in the teens to low 20's (degrees F).
I'm using a white LED flash light as a cold light source, this shines up thorough the condenser, back lighting the snow crystals. Colored gels are used for the bright field shots. I'm using a black obstruction in the middle of the condenser for the black field illumination shots. They need some work, I'm not happy with the results. My set up also doesn't work very well for large snow crystals, the magnification is too high, and I can't fill the entire frame in my camera. I can only image in the center of the frame. I haven't figured out how to use more of the image frame.
I hope this helps you, It's a lot a fun to do. good luck.
-Nick
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- Location: NW USA
Thanks Nick,
This is very helpful, thanks. I can rig up something similar, except that mother nature isn't as cooperative in the Oregon coast range...It's seldom in the teens; we tend to get more high 20's to 30's and horizontal sleet at my altitude....I suspect that the snow crystals I'll see will be more blobby...
David
This is very helpful, thanks. I can rig up something similar, except that mother nature isn't as cooperative in the Oregon coast range...It's seldom in the teens; we tend to get more high 20's to 30's and horizontal sleet at my altitude....I suspect that the snow crystals I'll see will be more blobby...
David
Yes, AO Spencer made DF condensers for your scope. See here:
http://user.xmission.com/~psneeley/Pers ... croAcc.zip
page 12 for what I think might be it. These come up on eBay quite often
http://user.xmission.com/~psneeley/Pers ... croAcc.zip
page 12 for what I think might be it. These come up on eBay quite often
Thank you psneeley,
I will have to keep and eye open on E-bay to see if I can find one. I'm only really interested in low power work currently so maybe just using a field stop in the 1.25NA condenser and removing the top element of it is all I need. But it's good to know AO Spencer made one, thanks for the information.
-Nick
I will have to keep and eye open on E-bay to see if I can find one. I'm only really interested in low power work currently so maybe just using a field stop in the 1.25NA condenser and removing the top element of it is all I need. But it's good to know AO Spencer made one, thanks for the information.
-Nick
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maybe mother nature did the work but you showed it to us
beautiful, great image quality too.
beautiful, great image quality too.
my FB page
I'm looking for the the extemely rare V-IM magnification changer for the E800 scope. If you have seen a listing or have one for sale please let me know.
I'm looking for the the extemely rare V-IM magnification changer for the E800 scope. If you have seen a listing or have one for sale please let me know.