scales of the urania ripheus

Adalbert · Post by **Adalbert** » Sat Nov 30, 2019 6:41 am

Hello Macrero,

Most likely I would have to saw the front part of the housing just like you did with yours

but fist try to unscrew the cylinder.

Can you show the part of the wing where those are located?

unfortunately not, because I have cut some places, stuck to the holder and destroyed the wing

e.g.

BTW, it may be interesting for you:
https://www.photomacrography.net/forum/ ... highlight=
BR, ADi

Macrero · Post by **Macrero** » Sat Nov 30, 2019 7:42 am

Sure, I will try to unscrew the cylinder first. That would be the best (and non destructive) way. Though I am not sure that it will be possible. I know the housing can be unscrewed, but it may be very hard to do so.

Thanks for the link, very interesting discussion. If I can remove the housing, I think I will not have problems with lighting. If I find it problematic, I will look for other ways to light.

No worries, I will buy one or a pair and I will examine them well. If the scales are there, I will find 'em

Best,

- Macrero

Adalbert · Post by **Adalbert** » Sat Nov 30, 2019 9:21 am

Hello Macrero,
Do you have any new idea how to illuminate at WD=1mm ?
BR, ADi

Lou Jost · Post by **Lou Jost** » Sat Nov 30, 2019 9:33 am

Would you want to give BD a try? Maybe it could be made slightly directional to give some modeling, by putting a diffuser in the BD cylinder. Especially since you have the BD objective.

Adalbert · Post by **Adalbert** » Sat Nov 30, 2019 10:12 am

Hello Lou,
I’m afraid the illumination from the side would be a little bit better in the case of the scales

BR, ADi

Lou Jost · Post by **Lou Jost** » Sat Nov 30, 2019 10:14 am

You're probably right, but at 1mm distance, the BD light is also coming from the side, right? I don't really know how it would look, I haven't used BD lighting, but I am curiosu about it...

Macrero · Post by **Macrero** » Sat Nov 30, 2019 10:16 am

Adalbert wrote:Hello Macrero,
Do you have any new idea how to illuminate at WD=1mm ?
BR, ADi

Adi,

I haven't worked much at high magnifications, but I have tried objectives with 1mm WD, and as long as the front part is cone-shaped and the front element is tiny (generally those high NA optics have very tiny front element), lighting is not big of a problem.

Actually it could be easier to light with 1mm working distance and cone-shaped objective with a tiny front element than with say 3-4mm WD, but with objective with a large front element.

I can't find the photo now, but I made a test stack with the Nikon PlanApo 20/0.75 (1mm WD) of a fly head, it wasn't hard to light. I posted it in a thread about the PlanApo 20/0.75, but I can't find it.

This is how the front part of the Oly 50/0.80 BD looks like:

For comparison this is a Oly LMPlanFl 50/0.50:

Removing the housing, there should be plenty of room/angle for lighting. But I will let you know how it does when I get it.

Best,

- Macrero

Macrero · Post by **Macrero** » Sat Nov 30, 2019 10:17 am

Lou Jost wrote:Would you want to give BD a try? Maybe it could be made slightly directional to give some modeling, by putting a diffuser in the BD cylinder. Especially since you have the BD objective.

Lou,

Never tried BD illumination. It would be interesting to try it out, though I am not sure if it is possible to get enough light on the subject as to work at reasonable shutter speed with BD lighting at high magnification.

Best,

- Macrero

Lou Jost · Post by **Lou Jost** » Sat Nov 30, 2019 10:20 am

I haven't tried it either, just wondering what it would be like. Seems worth a try since you have the objectbves for it.

Adalbert · Post by **Adalbert** » Sat Nov 30, 2019 10:39 am

Hello Macrero,
I have already tried to take the photographs with the Reichert Plan Fluor 100x / 0.95.
The reasonable illumination was not possible (only by accident

https://www.photomacrography.net/forum/ ... highlight=
I could image that you will get better results with your lens 50/0.50 than with the 50/0.80 BD because of the WD and illumination.
BR, ADi

Macrero · Post by **Macrero** » Sat Nov 30, 2019 10:44 am

Well, I have to remove (or saw

) the housing first, then I will try the objective with "conventional" ilumination. I am pretty positive it will work just well. If it does not, I will look into BD ilumination. The problem is that if I can't unscrew the housing and I saw it, it would be impossible to use BD ilumination

Well, I'll see. No hurry, winter is long...

- Macrero

Macrero · Post by **Macrero** » Sat Nov 30, 2019 10:59 am

Adalbert wrote:Hello Macrero,
I have already tried to take the photographs with the Reichert Plan Fluor 100x / 0.95.
The reasonable illumination was not possible (only by accident
https://www.photomacrography.net/forum/ ... highlight=
I could image that you will get better results with your lens 50/0.50 than with the 50/0.80 BD because of the WD and illumination.
BR, ADi

Adi,

what's the Reichert's WD? I would assume it is shorter than 1mm. While the Reichert's front part is cone-shaped as well, I think it will be easier to ligh with the Oly.

Well, I already bought the objective. I will let you know how it does when I get it.

Best,

- Macrero

Adalbert · Post by **Adalbert** » Sat Nov 30, 2019 11:28 am

Hello Macrero,

I would assume it is shorter than 1mm

yes, much smaller than 1mm

Yes, the biggest problem is the illumination and the second one the smallest step-size of your rail.
I usually take 3 photographs a DOF, so the step-size for my scales was 0,0003mm.

BR, ADi

Macrero · Post by **Macrero** » Sat Nov 30, 2019 11:47 am

Adalbert wrote:Hello Macrero,
I would assume it is shorter than 1mm
yes, much smaller than 1mm
Yes, the biggest problem is the illumination and the second one the smallest step-size of your rail.
I usually take 3 photographs a DOF, so the step-size for my scales was 0,0003mm.

BR, ADi

The difference in WD, even if seemingly small, can make a significant difference in lighting. Same for the shape/size of the front part/element.

As soon as I get the objective I will test it and will let you know how it does.

Here is an old, but interesting discussion about NA and WD at high magnification:

https://www.photomacrography.net/forum/ ... 21b0465eab

Best,

- Macrero

Adalbert · Post by **Adalbert** » Sun Dec 01, 2019 2:36 am

Hello Macrero,
Many thanks for the link!
BR, ADi