Search found 230 matches

by Din
Mon May 11, 2020 12:16 pm
Forum: For Sale / Trade
Topic: Request for holograms
Replies: 0
Views: 244

Request for holograms

Not really a sale or trade, but we got a request for holograms. Here is the email sent to me: "Hi all! I am looking for a quote on getting some white light reflection holographic films made and Alec at Integraf sent me here! I would be looking for 50-100 holographic films (not plates) with black bac...
by Din
Mon Mar 16, 2020 9:44 am
Forum: General Holography
Topic: Newport 481-A: how to use???
Replies: 12
Views: 662

Re: Newport 481-A: how to use???

PB = Peanut Butter Blaster... best lubricant ever... (LOL). (Joy here). Ive used those, I have similar, and I can double check one when I get into work today. The general idea is to loosen the knob to use the manual spin, but you must tighten it to use the fine micro. The issue is that is not quite ...
by Din
Thu Feb 20, 2020 11:40 am
Forum: General Holography
Topic: interferometro on line
Replies: 23
Views: 1224

Re: interferometro on line

It's mode hopping. The sudden shifting from one state to the other and back again is typical of mode hopping.
by Din
Fri Feb 07, 2020 12:35 pm
Forum: Gallery
Topic: opal
Replies: 4
Views: 9496

Re: opal

I'm afraid I've made a grievous error, for which I will forebear drinking Merlot for at least, oh about an hour. As the wife pointed out, opal does not have voids, it has solid spheres. These spheres act as diffractive structures, so it's the opposite of dcg, which has voids as diffractive structure...
by Din
Fri Feb 07, 2020 9:22 am
Forum: Gallery
Topic: opal
Replies: 4
Views: 9496

Re: opal

You have the same white light speck in the photograph of the opal, but the white light on reconstruction is more pronounced. There are also specks of white on the acrylic in the reconstruction. How was the opal illuminated during recording? If it was a shadowgram, the white light could be a 'hole' i...
by Din
Tue Nov 12, 2019 12:00 pm
Forum: Beginning Holography
Topic: Two issues - losing an object beam and spots on plate
Replies: 17
Views: 3807

Re: Two issues - losing an object beam and spots on plate

I think it could be motion. But, I think it's more likely that the light reflecting from the object is missing the plate. If your angles are correct as drawn, most of the light hitting the sides of the skull are reflecting away from the plate. I would look at just the object light (no reference) thr...
by Din
Tue Nov 12, 2019 11:47 am
Forum: holoforum administration
Topic: Denial of Service Attack (more or less)
Replies: 4
Views: 2757

Re: Denial of Service Attack (more or less)

If it's of any interest, I'm receiving a number of emails with Chinese characters. I just mark them as 'junk'. But, I wonder why I'm receiving these Chinese emails, and is any other holographer also receiving such emails?
by Din
Sun Aug 04, 2019 8:43 am
Forum: General Holography
Topic: Apodizing filter
Replies: 2
Views: 3561

Re: Apodizing filter

I wanted to use a apodizing filter to get a better uniform object light to make a reflection hologram. Is that a bad idea? Does it affect the polarisation or other laserlight parameters? No, it won't make any difference to any laser property, besides, of course, beam profile. Whether it's a good or...
by Din
Tue Jul 23, 2019 9:33 am
Forum: Beginning Holography
Topic: 3D Silhouette
Replies: 5
Views: 8634

Re: 3D Silhouette

It's for designing objects for 3D printing. It works with the Sillhouette Alta 3D printer. We use Blender for creating objects for 3D printing.
by Din
Mon Jul 01, 2019 8:06 am
Forum: General Holography
Topic: magnified hologram
Replies: 14
Views: 7560

Re: magnified hologram

The transverse magnification of a hologram recorded with reference at x(r), y(r), z(r) with an object at x((o), y(o), z(o), and reconstructed from x9c), y(c), z(c) is*: MT= dXi/dxo= 1/(1 +/-zo/mu*zc–zo/zr)(Meyer; paraxial) MT= (cos(alpha)o/cos(alpha)i){1/(1 +/-zo/muzc–zo/zr)} (Champagne; non-paraxia...