Euglena (images added)

Ichthyophthirius · Post by **Ichthyophthirius** » Sat Jan 04, 2014 4:46 pm

Hi Pau, That's right. It's a bit misleading if you have only the engraving as reference. But it is 0.17.

Just to double-check (and I suppose you know that already): Does the spring mechanism of the objective work? Zeiss objectives have a special feature in that the objective cone can be twist-locked in the upper position. Unreleased, this messes up parfocality and working distance.

Regards, Ichthy.

Litonotus · Post by **Litonotus** » Sun Jan 05, 2014 12:57 am

Interesting information you posted here (:

I only want to say that I ordered Marienfeld No. 1.5 coverglasses, it took me almost 2 moths to get them because of unbelieveable bureaucracy... They are expensive but there is a difference in image quality.

Pau · Post by **Pau** » Sun Jan 05, 2014 2:25 am

Ichthyophthirius wrote: Does the spring mechanism of the objective work? Zeiss objectives have a special feature in that the objective cone can be twist-locked in the upper position. Unreleased, this messes up parfocality and working distance.

Yes, with the spring mechanism locked up it doesn't ever focus at all. The parfocal difference with my other objectives is small, but with low contrast subjects, as I need to set DIC for each objective and with so small depth of focus and minute working distance, focusing is a bit difficult, not with the green euglena.

Jacek · Post by **Jacek** » Sun Jan 05, 2014 2:33 am

The second series of photos very good

Cactusdave · Post by **Cactusdave** » Sun Jan 05, 2014 3:19 am

This thread has produced some very worthwhile discussion on coverslips and high numerical aperture, high magnification objectives. So much so that it might almost be worth splitting that part off into one of the 'Techniques' headings?
I agree with most of what Ichthy says. I suspect, like me he has had a good deal of professional lab experience with the Zeiss X63, 1.4. I would only add a few practical points from personal experience. I mostly used this objective and the X40, 1.0 for immunofluorescence microscopy, where their high NA was of the greatest value in capturing weak fluorescence. I also worked with early confocal fluorescence setups. Samples would be wet preparations with coverslips roughly ringed with clear nail varnish to reduce evaporation and extend the viewing time.
We used quality branded no. 1.5 coverslips for routine work. Mostly Chance Propper. For confocal we used Marienfeld no. 1.5H coverslips. Even when we weren't spending our own money, these were treated as precious and kept separately. Of course we were using all Zeiss equipment, with perfect matching DIC components.
Coming back to these lenses after retirement, and necessarily working with less than mint examples that I could afford, and using them on mismatched stands, and in mismatched DIC systems. I find the X63 in particular a tricky customer. I don't now have any no. 1.5H coverslips, I use no 1 and 1.5 mostly, always from an established quality brand. For the type of subjects I look at, I have not found a huge difference on aberration with the X63 whether using n.1 or no. 1.5 slips. For a thick wet mount the no 1 gives a useful bit of extra 'head room'. For permanent mounts intended for this objective I would use a no. 1.5.
My advice to Pau would be to try the Spanish distributors of Marienfeld coverslips and see if they will send him samples of no. 1, 1.5 and 1.5H to test in his real world setup. If they won't play, to get some quality no. 1 and no 1.5 slips locally or from Ebay where Chance Propper and VWR are available. I wouldn't be afraid of using a no 1 with a thicker wet mount. Only you can decide whether any consequent degradation of the image is acceptable. Using mismatched DIC components introduces aberrations, but for practical reasons we live with them and work around them. Also as Ichthy and I have mentioned, using a fairly cheap micrometer guage, it is possible to know accurately the thickness of the individual slip you have in your hand. I don't do this personally, but have met people who do

.

arturoag75 · Post by **arturoag75** » Mon Jan 06, 2014 4:58 am

Ichthyophthirius wrote:
arturoag75 wrote:...you can see disturbing fringes blu and Yellow.
It's not necessarity a problem with the lens. The diatom sceleton also acts like a (silica) lens and can cause colour fringes that cannot be corrected by the objective. You can use green light and grayscale your image to get around that.

To get peace of mind, test the objective with an object that has zero thickness and is black and white, like an object micrometer. If you still see fringes, the problem could be: objective, tube length, eyepiece or camera adapation.

Regards,

Ichthy

oh yes it may be..but i had same results also with fresh water samples and why i have not the same bad results with others planapo lenses?

i think the "bad" is inside objective!

arturo

Pau · Post by **Pau** » Tue Jan 07, 2014 10:20 am

Again, thanks a lot Itchy, Dave an Arturo for sharing your knowledge. I'm a novice in working with high end equipment an is a pleasure and a privilege to learn from you.
Jacek, Lltonotus, tanks for your comments.

Cactusdave wrote:This thread has produced some very worthwhile discussion on coverslips and high numerical aperture, high magnification objectives. So much so that it might almost be worth splitting that part off into one of the 'Techniques' headings?

I've started a new topic, mainly to link to this intersting discussion. It would be easier to find in the future.
http://www.photomacrography.net/forum/v ... 670#139670

carlos.uruguay · Post by **carlos.uruguay** » Wed Jan 08, 2014 4:55 pm

Very interesting topic and photos.
The colorless euglenido can be Astacia (only 1 flagellum)
or Distigma (2 flagellum)
http://tolweb.org/Euglenida/97461
Regards
carlos

Pau · Post by **Pau** » Sun Jan 12, 2014 4:36 pm

Carlos, many thanks for your comment and for the ID clues. I think it may be Astacia.

Tom Jones · Post by **Tom Jones** » Sun Feb 02, 2014 12:27 pm

If anyone is interested, there are some micrometers for sale on *bay (#281242673608) for $15.99 plus $6.00 shipping. I bought one and it works well for this. The verniers read to 0.0001 mm.

The frames are short since they're actually wire micrometers, but you can read the edges of the cover glass easily.

Tom

75RR · Post by **75RR** » Wed Jan 28, 2015 1:21 pm

Have been offered a Zeiss Planapo 63x /1.4 160/-
Have not used it yet. Not sure I got this right.
Would a L & M 0.13-0.17mm thick Cover Glass do or not?

Pau · Post by **Pau** » Wed Jan 28, 2015 3:10 pm

I'm not sure to understand well what are you asking, as you did read in the former posts i'ts a very nice optic but exigent about cover glass and with extremly short working distance, so its application is limited to very flat slides but it can deliver the best resolution available at its time (and basically today too). If it isn't delamited and the price is reasonable go for it, if you don't find it adequate for your needs you can sell it later for a good price (over $300 if in very good condition)

75RR · Post by **75RR** » Wed Jan 28, 2015 5:04 pm

Hi Pau,
I suppose what I was trying to say was - have you changed the cover slips you use from Nahita covers marked 0.13-0.17 to something else and did you notice an improvement?
Not delaminated as far as I could see - was also offered a 100 PlanApo that did have some delamination. Gave that one back.

Pau · Post by **Pau** » Sat Jan 31, 2015 9:57 am

Hi 75RR,
I got good Marienfeld covers n1 and n1.5H thanks to another member help. I haven't done true tests (in fact I've made few slides lately) but they seem to work better.

75RR · Post by **75RR** » Sat Jan 31, 2015 11:11 am

Many thanks Pau.
Great euglena photos by the way!