I've joined the Bath group, completing this instrument in just a few hours. I found a very nice 13mm x 15mm DCX lens, a 15mm cube beamsplitter, a 1/10 wave flat mirror, and a laser module. I had bough

Thank you again for guiding my learning on how to use DFTFringe. My test mirror is going to be a challenge. My hope was that Igrams/DFTFringe would give me a general idea of mirror quality. I am inter

https://github.com/githubdoe/DFTFringe/releases/download/V6.1/DFTFrnge64Release61.exe * Version 6.1 * Added extensive features to dialogs accessed from simulation menu to create surface features * Add

Hello I want to test my 250mm flat mirror with DFTFringe. I built the flat years ago and tested it by combination with a 300 mm spherical reference (ROC 7320 mm)at 45 degrees with Foucault. Now, as I

Dale, When I view the "Star test, PSF, MTF" tab, is the assumption that the object is at infinity? This is mainly useful for paraboloids, with conjugates at infinity and RoC/2, but if you have for exa

I'm new to interferometry. I have a mirror to test. I'm not getting DFTFringe to do what the YouTube videos have me expecting. I found this group a bit ago, perhaps someone can set me on the right cou

Further to some interest in Ronchi Testing and simulations, I have revamped an old program which 1/ Is very easy, fast and instinctive to drive. 2/ Allows generation of a custom surface shape and a 3D

https://github.com/githubdoe/DFTFringe/releases/download/Ver6.2/DFTFrnge64Release62.exe Version 6.2 Enhanced report.pdf generation to make images better Remembers 3D control settings Added file save a

As I started to shape the mirror from the sphere to the parabola, it became more and more noisy.I can hardly check my work anymore.I'm afraid I can't make the mirror.

I would like to ask what the problem could be. When I want to save it says this. the same thing happens on all my computers.

This should be the last of my posts on bits and pieces of sometimes useful knowledge which some of the avid experimenters may find his useful. One of my main activities has been with Newton's Fringe t

Hi, I have DFTF4. Which version do i need to work with sorin.exe ? I could not find a cleanly identifiable DFTF download for latest installl in the files section. Could someone provide a link to lates

There are three basic holographic techniques for contouring a surface: two source points two frequencies two refractive media The latter is rarely used, though in some cases changing the gases might m

Hi, I'm interested in testing a gabbro (aka "black granite") surface plate optically. I've bought some optical flats and have a low pressure sodium lamp in transit. I've already got beam splitter, ret

Reg, How large is the surface plate you want to measure? I assume you know about NIST surface plate standard and specifications for various grades of surface plates such as A, AA, B etc. and the metho

A really ancient - almost historical - test for flatness when fine grinding prism surfaces was to let some Ethanol be drawn by capillary action at the contact line as shown. Ideally a long optical fla

I started assembling the DEBI kit I got from George and I'd like to say to all involved, "Well done!" Dale's design is excellent as is George's product. I hope to do much more elaborate stuff, but I w

Coloring a good surface plate with a No 2 pencil and rubbing will allow fringes to be seen at a low angle with a glass test flat and monochromatic light. The clay/graphite pencil material produces a m

Is there any benefit to adding a pinhole between the laser and the lens on the glass lens version? It will make the fringes a lot fainter, so it may be one step forward, two steps back. Has anyone inv

Beginning a Bath design and setup. For a camera I have purchased an older digital Pentax, thinking 6 Megapixels is enough. What I did not know that the Rear viewscreen is not LIVE...in other words I w