Oo La La, More French Diatoms

Here you can post pictures and videos to show others.
Post Reply
Message
Author
User avatar
rnabholz
Posts: 3066
Joined: Thu Jan 08, 2015 10:11 pm
Location: Iowa USA
Contact:

Oo La La, More French Diatoms

#1 Post by rnabholz » Tue Sep 11, 2018 12:54 am

Maybe you all will like darkfield better than oblique? More fossil diatoms from St Laurent La Vernede.

American Optical 10, 100x Plan Achro Iris Oil, toric darkfield condenser, Canon 70D, captured in green light, converted to grayscale in post processing, stacks as noted, Zerene Stacker using the PMax process.
44µm  Stack of 6
44µm Stack of 6
St Laurent La Venede 9838-43 ZS PMax Final.jpg (52.99 KiB) Viewed 1394 times
44µm  Stack of 3
44µm Stack of 3
St Laurent La Venede 9835-37 ZS PMax Final.jpg (124.55 KiB) Viewed 1394 times
44µm Stack of 5
44µm Stack of 5
St Laurent La Venede 9830-34 ZS PMax Final.jpg (88.83 KiB) Viewed 1394 times
50µm Stack of 17
50µm Stack of 17
St Laurent La Venede 9844-60 ZS PMax Final.jpg (126.95 KiB) Viewed 1394 times

User avatar
zzffnn
Posts: 2712
Joined: Sat Jun 20, 2015 3:57 am
Location: Houston, Texas
Contact:

Re: Oo La La, More French Diatoms

#2 Post by zzffnn » Tue Sep 11, 2018 3:15 am

Very nice work, Rod. Your oblique and darkfield images are both beautifully done. I think it is just that forum members still catching up with new posts.

Have you tried stacking circular oblique light mask? For some diatoms, COL works better than offset oblique.

DF is simply an oversized COL. Your DF works very well, so I am guessing COL may work nicely too. I am just curious.......

Hobbyst46
Posts: 2182
Joined: Mon Aug 21, 2017 9:02 pm

Re: Oo La La, More French Diatoms

#3 Post by Hobbyst46 » Tue Sep 11, 2018 7:38 am

Very nice images. Thanks for posting.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

User avatar
rnabholz
Posts: 3066
Joined: Thu Jan 08, 2015 10:11 pm
Location: Iowa USA
Contact:

Re: Oo La La, More French Diatoms

#4 Post by rnabholz » Tue Sep 11, 2018 11:40 am

zzffnn wrote: Have you tried stacking circular oblique light mask? For some diatoms, COL works better than offset oblique.

DF is simply an oversized COL. Your DF works very well, so I am guessing COL may work nicely too. I am just curious.......
Thanks zz

I have an interest in trying COL, but could use a reference on how to go about it. Any you can refer me to?

User avatar
rnabholz
Posts: 3066
Joined: Thu Jan 08, 2015 10:11 pm
Location: Iowa USA
Contact:

Re: Oo La La, More French Diatoms

#5 Post by rnabholz » Tue Sep 11, 2018 11:41 am

Hobbyst46 wrote:Very nice images. Thanks for posting.
Thanks Hobby.

User avatar
zzffnn
Posts: 2712
Joined: Sat Jun 20, 2015 3:57 am
Location: Houston, Texas
Contact:

Re: Oo La La, More French Diatoms

#6 Post by zzffnn » Tue Sep 11, 2018 6:22 pm

Rod,

Paul James did a 4 part write-up on COL before: http://www.microscopy-uk.org.uk/mag/ind ... pjcol.html

Using the right mask size and mask centration is key. To start, close down condenser iris to around 85% of objective NA, then vary mask sizes. When in doubt, try smaller mask; if illumination ring is too narrow (mask being too big), halo and shadow may be too severe (such that it would reduce resolution).Thick diatoms may require a slightly smaller mask size than thin diatoms.

Here is another article about COL by Ted Clarke: http://www.microscopy-uk.org.uk/mag/ind ... c-col.html

MicroBob
Posts: 1528
Joined: Sun Dec 25, 2016 9:11 am

Re: Oo La La, More French Diatoms

#7 Post by MicroBob » Tue Sep 11, 2018 8:13 pm

rnabholz wrote: fossil diatoms from St Laurent La Vernede
Hi Rod,
your nice images remind me that I have some cleaned material from this location that I still haved not looked at! The fall is coming soon and I hop to make some nice slides from it.

Bob

User avatar
rnabholz
Posts: 3066
Joined: Thu Jan 08, 2015 10:11 pm
Location: Iowa USA
Contact:

Re: Oo La La, More French Diatoms

#8 Post by rnabholz » Tue Sep 11, 2018 9:51 pm

zzffnn wrote:Rod,

Paul James did a 4 part write-up on COL before: http://www.microscopy-uk.org.uk/mag/ind ... pjcol.html

Using the right mask size and mask centration is key. To start, close down condenser iris to around 85% of objective NA, then vary mask sizes. When in doubt, try smaller mask; if illumination ring is too narrow (mask being too big), halo and shadow may be too severe (such that it would reduce resolution).Thick diatoms may require a slightly smaller mask size than thin diatoms.

Here is another article about COL by Ted Clarke: http://www.microscopy-uk.org.uk/mag/ind ... c-col.html
Thanks zz.

Sounds a bit tricky to dial in. I'll look into it.

User avatar
rnabholz
Posts: 3066
Joined: Thu Jan 08, 2015 10:11 pm
Location: Iowa USA
Contact:

Re: Oo La La, More French Diatoms

#9 Post by rnabholz » Tue Sep 11, 2018 9:53 pm

MicroBob wrote:
rnabholz wrote: fossil diatoms from St Laurent La Vernede
Hi Rod,
your nice images remind me that I have some cleaned material from this location that I still haved not looked at! The fall is coming soon and I hop to make some nice slides from it.

Bob
Thanks Bob.

My sample is very centric heavy, all sizes including some pretty big ones. There are some other forms scattered too, as you can see.

Good Luck with it.

Rod

Charles
Posts: 1108
Joined: Mon Mar 02, 2015 11:55 pm

Re: Oo La La, More French Diatoms

#10 Post by Charles » Thu Sep 13, 2018 12:12 am

Beautiful Rod!

User avatar
rnabholz
Posts: 3066
Joined: Thu Jan 08, 2015 10:11 pm
Location: Iowa USA
Contact:

Re: Oo La La, More French Diatoms

#11 Post by rnabholz » Thu Sep 13, 2018 3:06 am

Charles wrote:Beautiful Rod!
Thank you Charles!

User avatar
vasselle
Posts: 2763
Joined: Sat Oct 25, 2014 5:32 pm
Location: France

Re: Oo La La, More French Diatoms

#12 Post by vasselle » Wed Sep 19, 2018 7:44 pm

Bonjour
Superbes images
Microscope Leitz Laborlux k
Boitier EOS 1200D + EOS 1100D

Post Reply