MicrobeHunter.com Microscopy Forum

I would like to use this comparison chart to illustrate the problem. The Chinese translation in the picture is as follows:
From left to right

NFK 2.5 direct projection 120%

NFK 3.3 Direct Projection 100%

NFK 3.3+PMTVC 194%

Equipment: BHS NIC SPlanc 40X

Which setting do you prefer?

The NFK 3.3 Direct Projection 100% looks crisper to me

MichaelG.

These three are pretty different, hard to compare. They should all give similar image quality in theory assuming they are used with an appropriate sensor.

As is well known, the BH2 series camera system is designed for film cameras, so in my humble opinion, there is no 'most suitable digital camera accessory'.

Additionally, these three images are of the same specimen, same objective, and same camera, so of course they can be compared.

Allow me to include the complete picture, you should be able to see this.
Best Regards


By the way, perhaps you have noticed that PMTVC images are actually stacked with focus, while the other two are not. Therefore, according to my eyes, NFK2.5 direct projection achieves better resolution.

It's important to match focus and lighting across test shots to compare fine differences in image quality.

Scarodactyl wrote: ↑

Fri Apr 21, 2023 6:03 am

These three are pretty different, hard to compare. They should all give similar image quality in theory assuming they are used with an appropriate sensor.

Agreed. More importantly, the settings are useless if they add "false resolution" and add information that isn't there. Instead of asking which setting "looks better", the OP should dig out a SEM image of this plankton (the gold standard for subject calibration) and compare the settings to that. Interference contrast is notorious for, among other things, flipping relief; add to that the problems that modern, high resolution sensors create.

It's helpful to add some scale or F.O.V.
Often in a strew the distance from the coverslip is not helpful.
It can help with a slow drying mountant to let it sit cover slip down so if there is settling it's in your favour.
For inverted obviously not the case.
Looks like something isn't aligned optimally.
Could be either side of the subject but more likely below?

Focus plane (Z axis) of those photos are different, so I don’t think they are comparable. You would want to centrally focus onto the exact same dot on the exact same diatom for a fair comparison. The same diatom has many layers of Z axis focus planes, when some dots are defocused, they will not look sharp.

woyjwjl wrote: ↑

Fri Apr 21, 2023 1:26 am

Which setting do you prefer?

None appear to have appreciably more detail,
but converted to grayscale, the left has more contrast that the middle.

To be honest, I feel very confused

Why is it that some people cannot understand? This is just showing the applicability of different photography eyepieces

In that case, please allow me to waste some more space From left to right:
NFK2.5 direct projection

NFK3.3 direct projection

NFK5 direct projection

NFK５＋ＰＭＴＶＣ

Add a piece of nonsense: Just replace the NFK eyepiece.

As for the application of DIC on diatoms, it seems that I have never attempted to prove the importance of SEM, so please calm down and appreciate it.
https://fossil-diatoms.com/atlas/index.php

This is a weirdly indignant response to some pretty basic posts. I'm going to leave it at that.

To non original English speakers language issues on the fine details of what is expressed may be the cause of misunderstanding (I’m Dutch).

On my BH2’s switching from NFK2.5 setup with the standard Photomicro adapter L to the MTV-3 adapter with NFK3.3 requires fine adjustment of the focal plane (z-axis).

The standard PMTCV or MTV-3 contain optics, so a difference in image quality is to be expected: think the OP is trying to figure out these differences.

Best, deBult

deBult wrote: ↑

Sun Apr 23, 2023 5:22 am

To non original English speakers language issues on the fine details of what is expressed may be the cause of misunderstanding (I’m Dutch).

On my BH2’s switching from NFK2.5 setup with the standard Photomicro adapter L to the MTV-3 adapter with NFK3.3 requires fine adjustment of the focal plane (z-axis).

The standard PMTCV or MTV-3 contain optics, so a difference in image quality is to be expected: think the OP is trying to figure out these differences.

Best, deBult

Thank you for your explanation. I am indeed using translation software to handle language issues.

Yes, by 'direct projection' I mean not using any intermediate optical components.

What I imply is that adding intermediate lenses does not bring any benefits.

Best, Lei

Each diatom even of the exact same species from the same sample has minute dimensional difference, SEM is a good tool to standardise the metrics, otherwise you are just assuming, which makes diatoms an inadequate tool to assess resolution.

Why DIC? It would be far simpler to take a brightfield photo of a ruler.

Anyway, not a fan of projection eyepieces but I have to use them so oh well.

Additionally, 直焦 means without any relay/compensating optics whatsoever (we can ignore Zeisseica and their weird tube lens corrections for this one). When you are using a projecting eyepiece and/or PMTVC, that is not direct focus/projection.

Taking screenshots adds in unwanted artefacts/compression which further invalidates the comparison.

Macro_Cosmos wrote: ↑

Tue May 09, 2023 12:37 am

but I have to use them so oh well.

Why not use a longer tube lens?