How good are these DIC images?

pwnell · Post by **pwnell** » Wed Jun 20, 2012 10:30 pm

I want to know whether you guys producing superb results consider these average, below average or above average. I know getting a good image is a combination of equipment, skill and sample preparation. Please be as direct as possible.

Zooxanthellae and nematocyst of Aiptaisia sp. @ 1200x DIC

Single nematocyst @ 1200x magnification, DIC:

Red flatworm (marine) @ 800x IIRC

Red flatworm (marine) @ 400x IIRC

Unknown organism, fresh water, 800x

Freshwater diatom (?), 800x

Freshwater diatom, 800x

curt0909 · Post by **curt0909** » Wed Jun 20, 2012 10:43 pm

These are good images. Have you tried moving the upper prism or (on some scopes) rotating the polarizer to create a little more background extinction. What type of scope are you using?

pwnell · Post by **pwnell** » Wed Jun 20, 2012 10:46 pm

The polarizer and analyzer are at exactly 90 degrees to each other, at the position where they provide the darkest image without the prism in the optical path. I did fiddle with the prism's shear adjuster and set it to a value that looked pleasing and that had uniform background, but still good DIC effect. As I am new to this I might have done it incorrectly.

This is a Olympus BX53 with SPlanApo's.

curt0909 · Post by **curt0909** » Wed Jun 20, 2012 11:00 pm

Ah that explains it. Olympus SPlan objectives are finite 160mm tube length corrected. The BX53 is designed for Olympus 180mm tube lens infinity corrected objectives. DIC prisms are calibrated very precisely and to use a finite objective on an infinity system is a crap shoot. I have a similar set up, a reichert diastar. It has quite a lot in common with the olympus bx in that it is infinity and uses a single upper prism. The DIC is great with its own objectives but it gives poor results with my nikon plan apos 160mm finite objectives. Luckily the 60x 1.40 plan apo works perfectly(even better than my reichert 100 1.3 plan fluor) with the 100x condenser prism. I would suggest trying some olympus infinity objectives and see if you get a better result.

Cactusdave · Post by **Cactusdave** » Thu Jun 21, 2012 12:39 am

I tend to agree with Curt. There is a certain lack of DIC contrast, which is probably due to the mismatch of objectives. Nevertheless these are good images and a little more could be done to make the images you already have more revealing by carefully post processing with attention to enhancing contrast and light sharpening.

pwnell · Post by **pwnell** » Thu Jun 21, 2012 7:37 am

Cactusdave wrote:I tend to agree with Curt. There is a certain lack of DIC contrast, which is probably due to the mismatch of objectives. Nevertheless these are good images and a little more could be done to make the images you already have more revealing by carefully post processing with attention to enhancing contrast and light sharpening.

Hmm they are already post processed... Exposure, contrast, sharpening etc.

pwnell · Post by **pwnell** » Thu Jun 21, 2012 7:40 am

curt0909 wrote:Ah that explains it. Olympus SPlan objectives are finite 160mm tube length corrected.

Are you sure? According to this link these objectives are infinity corrected unless I misread it:
http://www.olympusamerica.com/oai_press ... ressNo=354

http://microscope.olympus-global.com/uis2/en/

Jacek · Post by **Jacek** » Thu Jun 21, 2012 9:10 am

For me, your pictures are beautiful

pwnell · Post by **pwnell** » Thu Jun 21, 2012 9:15 am

Thanks Jacek. I am reviewing the BX53 microscope and need to decide between it and the Leica DM2500.

arturoag75 · Post by **arturoag75** » Thu Jun 21, 2012 10:51 am

Hi,
i find thes shots like excellent

best
arturo

BJ · Post by BJ » Thu Jun 21, 2012 11:04 am

Waldo,

i suppose that one can always do better, but I would love to be able to produce such images - congratulations !

The first green "diatom" is the saccoderm desmid Netrium interruptum. For me there is a small problem with the image - the chloroplast edge could be crisper and the crystal in each of the terminal vacuoles is out of focus and perhaps has an artificial colour. But, perhaps these issues are merely to do with choice of focus.

regards
Brian

Pau · Post by **Pau** » Thu Jun 21, 2012 11:20 am

The pictures look nice, in special the last two ones that have specimens that are more contrasty itselfs.

But I think a BX must do better, your pictures are nice but the contrast isn't high enough for my taste. Members ABEL and discomorphella had shown pictures taken with DIC BX microscopes with much higher contrast. ABEL's ones even match Rogelio's legendary high contrast.

I supose that you're aware that Olympus sell four different objective prism sliders with different contrast. What model is yours?. Are the condenser prisms designed to match your objectives?

Perhaps playing with the condenser height and the objective common DIC slider position you may get better contrast. The fist goal is to have the field as black and uniform as posible to beguin and after that to tune the desired contrast adding shear while translating the objective prism.

(in my poorman's hybrid DIC microscope I need to do this with each objective and even with each different slide)

pwnell · Post by **pwnell** » Thu Jun 21, 2012 11:42 am

Pau wrote:I supose that you're aware that Olympus sell four different objective prism sliders with different contrast. What model is yours?. Are the condenser prisms designed to match your objectives?

I am using the universal prism slider (U-DICTS BX2). This is to give a balance between contrast and resolution. The objectives are UPlanSApo's, the prisms are U-DICxx NA 0.9. I presume they are matched as this is a brand new system I am about to order and this is how Olympus configured it.

The system is set up for Kohler illumination so I have not changed the height of the condenser from its set position. Will try.

curt0909 · Post by **curt0909** » Thu Jun 21, 2012 2:03 pm

pwnell wrote:
curt0909 wrote:Ah that explains it. Olympus SPlan objectives are finite 160mm tube length corrected.
Are you sure? According to this link these objectives are infinity corrected unless I misread it:
http://www.olympusamerica.com/oai_press ... ressNo=354

http://microscope.olympus-global.com/uis2/en/

UPLSAPO objectives are infinity but in your original post you said you were using SPLANAPO objectives. I was referring to those.

pwnell · Post by **pwnell** » Thu Jun 21, 2012 2:22 pm

curt0909 wrote:UPLSAPO objectives are infinity but in your original post you said you were using SPLANAPO objectives. I was referring to those.

Sorry, I presumed that UPlanSApo and SPlanApo were one and the same. Not familiar with all their objective ranges.