emulsion thickness

[Din]

I have a spectrophotometer, which incorporates a spectrometer, so I would be interested in knowing how a spectrometer can be used to measure an air gap.

It is possible. I can give you details, if you wish. However, I suspect that Hess didn't actually do anything besides pressing buttons on a piece of equipment he didn't understand, since he can't give any details, any references or any publications, or any mention of how to interpret results from the spectrometer. it's very easy to say "I did <this>", but going silent when asked for details brings to mind a story about an emperor.

Noticed this (claiming 0.1micron resolution) for $339 (?):

https://www.amazon.com/Accuracy-Sub-Mic ... B07K358Q3W

https://www.youtube.com/watch?v=wWRWw4Rz2qA

I doubt the figure of 0.1u. The uncertainty in the surface of the measuring cylinder is probably greater than 0.1u. In the video, the user doesn't actually measure anything, which also raises my suspicions. The typical dimensions of a dust particle is ~ 1u, while human hair is about 20 - 80u. It would have been a more useful demonstration to show common objects actually being measured.

[Din]

I expect Mr. Pratheep can ask for clarification himself, if necessary after reading the linked information in my response. I used an Ocean Optics USB2000 spectrometer at Digilens for the measurement, and still do today.

But, you can;t give any details, any procedure, any results. We're simply supposed to take your word on this as a matter of faith?

In technical issues, such as issues regarding physics or engineering, details, references and experimental results are required to check the technical value. Very few engineers and scientists take anything on faith! Those who comment on engineering matters who then expect to be "believed" as a matter of faith, don't have a lot of credibility with scientists and engineers. Anyone can say "I did <this>".

[BobH]

Those who comment on engineering matters who then expect to be "believed" as a matter of faith, don't have a lot of credibility with scientists and engineers.

I suppose that's why I am currently busy working on multiple HOE projects with multiple clients, and you're sitting at home trolling the only holography related forum that will still allow your presence, despite having been booted from even here at least once before for your inaccurate and disruptive behavior, like that seen in this thread.

All I did was answer a simple question with a simple solution, from direct experience. The bit about polarization is totally off topic and only there to troll me with insanity, but I don't care.

[dannybee]

Hum Bob H wish ther was a like button on here

[Din]

Those who comment on engineering matters who then expect to be "believed" as a matter of faith, don't have a lot of credibility with scientists and engineers.

I suppose that's why I am currently busy working on multiple HOE projects with multiple clients, and you're sitting at home trolling the only holography related forum that will still allow your presence, despite having been booted from even here at least once before for your inaccurate and disruptive behavior, like that seen in this thread.

All I did was answer a simple question with a simple solution, from direct experience. The bit about polarization is totally off topic and only there to troll me with insanity, but I don't care.

I'm sitting at home because I'm retired. At 70 years of age, I believe it's reasonable to be retired without being insulted!

"Trolling" and being "disruptive" is highly insulting and I hope you can prove your assertions. "All" you did was to claim to answer the question by an Indian researcher (is he also a troll, I wonder, because he's of Indian origin as well?). When this Indian researcher asks a question, you presume to give an answer with a vague statement with no evidence; and then demand he can ask you. I think he did ask, and you ignored him. Without giving any details of your methods, the claim seems not to have any value. "All" you seem to do is to make claims that are largely without any references. "All" you did was to say "I did <this>" Anyone can say "I did <this>". Whether you actually did anything at all should be based on evidence and/or references, not empty insults! Do you have any evidence, any results, any principle behind the measurement, anything at all besides the ego that all your statements must be taken on faith alone?

By the way, you also claim that holography does not record phase information. All literature on the subject from Diffractive Optics, Fourier Optics and Physical Optics state that holography is a method of phase capture and reconstruction. I'm still waiting for a reference for this highly unusual statement. I bring this up because it lends credibility, or the lack of them, to your claims.