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Ciao,Today I finished with 220 and I did the test to check the focus and I can say that so far we sono.Poi I wanted to see if the distance of the radius of curvature (3000 mm) lit up the mirror focusing with laser, it has not’ nothing happened.
Now I wonder e'troppo soon because I will illuminate the mirror?
The laser was not right?
The mirror goes wet?
Where mistake?
thank youhello Maurizio.
What test did you use to measure the focal?
Surely it is still better to wet the mirror to the measures.hello Deabis,
for the test I saw your video, but not having a strong enough source of light
I used the sun as my part and’ a nice day.ps :province of Rome
hello Maurizio, as he said deabis the mirror must be wet for the measures, only when it is polished will reflect ( more or less 5% ) the light.
As surely got the sun measure the fire and then you will have a measurement error of a few millimeters because the mirror is not spherical and focuses the rays to a single point, while measuring the radius of curvature of the measurement is precise ( only for the spherical mirror ) and it will be divided by two to get the focal length.
Conversely with the parabolic mirror you will have an unambiguous measure for the fire and several measures for the radius of curvature.Hi guys,I'm seeing the photos networked by Massimo for costruzzione of Foucault and at the same time I'm also testing consulting the book where Texereau
c’e’ a fixed rod with scale in mm and a drum but I can not understand com’ e’ I divided the scale on tamburo.Ho printed on A4 paper division of Massimo drum and there are two examples :the first is from 0 until 1,35 and the second from 0 until 1,4 in short, I have a bit of confusion .thank you
maurizio
Then,I try to clarify my messy project
:
The scale runs from 0 until 1,5 mm in both cases, a complete revolution corresponds in fact to the advancement of the threaded bar 1,5 mm.
In the first case it is divided in step 0,15 mm, in the second case it is in decimal scale, The only difference concerns the personal choice of which to use for better legibility, the important thing that a full turn corresponds to the pitch of the threaded rod.The bar that I have used is a standard M10 pitch 1,5 mm. This scale is fine only when used with an M10 bar.
For example, if you want to use a threaded rod M6 ( it would be better ) then the thread pitch is exactly 1 mm, then at each revolution of the dial corresponds to the advancement of 1 mm.
In this case you have to redo the scale to fit the new step.Eye that this tester differs from the original design of Texereau substantially.
The Texereau tester is comprised of a support which rests on a fixed axis , support and advance is made to slip by screwing a screw that pushes and maintained in traction with the springs, the tester instead article does not use springs and the forward-back movement of the support takes place by means of the rotation of the threaded rod on to which the support is pivoted with long nuts.Ciao,I'm done with the grain 1000 but I realized that there are 2 small scratches that you only notice with the lens ,You think that the next processing with the pitch patina and cerium will be deleted?
Is’ to evaluate the size of rows, if they are comparable to the grain 800 go away smoothly with cerium, they are more similar to 600 They go away too but it takes longer, considering that you have not yet begun polishing, a small scratch within these limits I would leave it alone and procederei pitch with patina and cerium, but if the width of the scratches is higher than the 600 should go back with some abrasive. In any case a little scratch mild extension does not affect the optical goodness,at the end of polishing it will surely be absorbed largely, one to which we must pay attention to is that from now on do not come more, that is, one must understand what they were generated, it is often the edge chamfer not finished properly to ensure that some small flakes from detaching from the edge generating these scratches.
Hi guys,
I resumed work on the mirror and I came to polishing (3 hours)
I tried to do the Ronchi test and would like some advice I seem to me that there is an edge wrong (I do not know itself raised or retorted) and I not know what to do I tried to take some pictures, and better than that I can not,I try to put the photo
hello Maurizio, to insert a photo you must first upload images to a website hosting Free eg. http://www.postimage.org.
Once you uploaded the pictures you will open a page with links to each picture.
Copy the link “direct link” and paste the post.but if you want an image to appear in the preview post, Click on the tag “img” on the toolbar , and paste the link on the window that will open.
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