A Macro Beauty-dish Diffuser

rjlittlefield · Post by **rjlittlefield** » Wed Dec 23, 2009 12:00 pm

The BAT wrote:Great test that covers just about everyone's DIY chosen 'medium'.

My personal favorite is Kleenex tissue, not included in the array.

There's a comparison of Kleenex tissue versus thin packing foam HERE and in followup posts.

There is also some relevant discussion earlier in that same thread, particularly HERE.

Of course the photos being discussed appear at the start of that thread, HERE.

--Rik

The BAT · Post by **The BAT** » Wed Dec 23, 2009 4:51 pm

Hi Rik,
As you know (??) it's summer here in Oz and the sun is blazing, so no need for the Kleenex box at the moment. I will break it out of storage and try some out as new diffuser material. I have some nice 'aloe vera' scented ones, so they should be good for my hands as well. . . .

Merry x-mas my friend,
Bruce

rjlittlefield · Post by **rjlittlefield** » Wed Dec 23, 2009 7:18 pm

The BAT wrote:As you know (??) it's summer here in Oz and the sun is blazing

I do know that, but it's the funny sort of "I know it if I think about it, but only if I think about it".

As far as immediate intuition goes, I'm convinced it's winter everywhere right now!

Have fun in the sun!

--Rik

LordV · Post by **LordV** » Wed Dec 23, 2009 11:56 pm

augusthouse wrote:DQE wrote:
In any event, these very unusual materials seem interesting to think about and to experiment with for this application. I wish it were easy to obtain a few large sheets of each of these materials. If one works for a company or university, it might be possible to obtain some free samples directly from 3M. Not sure they would be interested in supporting a hobbyist's tinkering, though!
They might be scratching their heads if they suddenly start receiving incoming emails from photographers; but no harm in asking.

http://solutions.3m.com/wps/portal/3M/e ... ersamples/

*later note: Here is the response to a request for samples I sent via the form at the link above.

Thank you for your interest in 3M Vikuiti(TM) film.
Based upon the information provided, you would be better served by www.digikey.com or www.apioptics.com.
Craig

*edited to include response to a samples request.

Craig - yes I went throught this when I got my sample of the film - I actually got it from a supplier. They even sent a little water spray gun and spreader - you have to apply this film to a wet surface and then use the spreader to get out any trapped water

Brian v.

The BAT · Post by **The BAT** » Thu Dec 24, 2009 12:26 am

Hi Brian,
Is this 'sample' the film that you are now using, or did you revert back to your older recycled sample? AND,
Was the supplied sample successful or not for your intended use?
Bruce

LordV · Post by **LordV** » Thu Dec 24, 2009 12:36 am

The BAT wrote:Hi Brian,
Is this 'sample' the film that you are now using, or did you revert back to your older recycled sample? AND,
Was the supplied sample successful or not for your intended use?
Bruce

Hi Bruce.
No it's not the same film I was originally talking about. I do still have the diffuser with this back projection film on it but the light loss is a bit high and I haven't used it for a while.
The original films I am using were all from an old PC LCD screen.
Brian v.

The BAT · Post by **The BAT** » Thu Dec 24, 2009 5:25 am

Hi Guys,
I have just finished my own DIY diffuser and now that I have worked out how to post images onto the site properly, I will get some pics together and post a short report. . . . it is working really well...IMHO

Bruce

augusthouse · Post by **augusthouse** » Thu Dec 24, 2009 5:28 am

Sounds good BAT!

Looking forward to seeing it

Craig

PaulFurman · Post by **PaulFurman** » Thu Dec 24, 2009 10:35 am

One material I've found works very well is translucent white plastic shopping bags. And the idea of layers is good, interior designers use layered thin white curtains for soft window light and there is a plastic greenhouse/sun-room material like corrugated cardboard with high light transmission and it is very soft diffuse light because of that 1/4 inch separation of layers.

<proceeding to dismantle my old broken laptop screen>

g4lab · Post by **g4lab** » Thu Dec 24, 2009 1:46 pm

Where I work one of the Profs that I work for asked me to see if I could resurrect an LCD screen which I could not. Since it was headed for the trash I dissected it and got some of these materials too. A one quarter inch thick piece of textured lucite. Various diffusion films and I also kept the cold cathode lamps and the power supplies for same.

There also was a wonderful white plastic back reflector layer.
I think I will dissect a few of these.

Charles Krebs · Post by **Charles Krebs** » Thu Dec 24, 2009 6:13 pm

Paul... you need to be a little careful with white plastic bags. Some seem to "filter" out much of the blue light and can lead to quite ruddy results.

I'm enjoying this discussion, but will admit I am a little perplexed that there's been no mention of the many various polyester Lee and Rosco products that specifically made to diffuse light. Certainly tougher than paper towels and tissue, nice clean color, and not very expensive. If you have access to a store with a "pro" lighting department you can buy it by the "foot" from a 48 or 60 inch roll at a very reasonable price. (Or you can order sheets online at a place like this http://www.filmtools.com/leedifsheetx.html).

There's a pdf here that compares the "diffusion" of the various Lee materials.

The BAT · Post by **The BAT** » Thu Dec 24, 2009 6:27 pm

Charles Krebs wrote:I'm enjoying this discussion, but will admit I am a little perplexed that there's been no mention of the many various polyester Lee and Rosco products that specifically made to diffuse light. Certainly tougher than paper towels and tissue, nice clean color, and not very expensive. If you have access to a store with a "pro" lighting department you can buy it by the "foot" from a 48 or 60 inch roll at a very reasonable price. (Or you can order sheets online at a place like this http://www.filmtools.com/leedifsheetx.html).
.

Hi Charles,
I have just finished making my own diffuser as I said previously and the material that I have used for the front panel is a clear plastic can sealer, but onto this I have stuck some of the window frosting/light diffusing self adhesive plastic film that hardware stores sell for 'privacy' windows, eg., bathrooms.
When I purchased this film, (by the roll) I was told/guaranteed that it would only filter out one stop of lighting. I origionally purchased this film for my underwater strobes, where it was extremely successful, but have now found it to be very good for what I am now trying to achieve.
BTW, you can also buy 'window frosting' in an aerosol can and gently spray 'layers' onto plastic until you have the desired thickness/spread of diffusion required. I have also used this on my underwater strobes.
HTH,
Bruce

augusthouse · Post by **augusthouse** » Thu Dec 24, 2009 7:59 pm

Charlie wrote:

...there's been no mention of the many various polyester Lee and Rosco products that specifically made to diffuse light.

Looking through my collection of Rosco swatch books now.

Rosco provide detailed specifications on their website.

http://www.rosco.com/us/filters/roscolux.asp

http://www.rosco.com/us/products/lighting.asp

Roscolux #111 'Tough Rolux' looks like a good candidate for the 'outer' diffuser.

There is almost an endless selection of filters/possiblities for the separate center weight/central reflector component as detailed in John's original post. The small swatches themselves could be used for this critical component, attached midway between flash head and 'outer' diffuser?

P.S. This material is also excellent for making diffuser cylinders for tabletop setups.

Craig

DQE · Post by **DQE** » Thu Dec 24, 2009 8:45 pm

Charles Krebs wrote:Paul... you need to be a little careful with white plastic bags. Some seem to "filter" out much of the blue light and can lead to quite ruddy results.

I'm enjoying this discussion, but will admit I am a little perplexed that there's been no mention of the many various polyester Lee and Rosco products that specifically made to diffuse light. Certainly tougher than paper towels and tissue, nice clean color, and not very expensive. If you have access to a store with a "pro" lighting department you can buy it by the "foot" from a 48 or 60 inch roll at a very reasonable price. (Or you can order sheets online at a place like this http://www.filmtools.com/leedifsheetx.html).

There's a pdf here that compares the "diffusion" of the various Lee materials.

Similarly, B&H sells a pack of twelve Bogen FP211 Diffusion Filter sheets, with varying degrees of diffusion. The size is 12 x 12 inches (30 x 30 cm). I bought this set and was reasonably satisfied with their uniformity, quality and utility. They are made to good quality specs, based on the BH specs page, hopefully avoiding unwanted color casts, etc, in photographic uses. As best I could tell from a superficial examination, they use tiny matte beads in a coating to create the light diffusion. Such matte beads are commonly used in various gloss-reduction spray paints and coatings to create a dull or light-diffusing surface. A link to this inexpensive (23 US dollars) set of filter sheets is provided below:

http://www.bhphotovideo.com/c/product/2 ... Pack_.html

Interestingly (from distant memory), 3M embeds tiny spheres in a paint to create a retroreflective surface, as seen in reflective tapes and signs. These little spheres geometrically retroreflect incident light when immersed in a medium of a certain refractive index if my aging distant memory is mostly correct for a change.

Diffusing light through optical turbidity is a surprisingly important branch of optics and materials design. Titanium oxide powder (again from distant memory) is commonly used as an efficient white diffuse reflector. Barium sulfate is highly reflective and optically diffusive as a powder. Also, tiny methyl methacrylate spheres are often coated onto surfaces to create a light diffusing effect, but my aging memory is incomplete as to the common applications of this material.

An enjoyable discussion, with a nice mixture of DIY experimental efforts and commercial materials. I continue to have the impression that macro photographic illumination has not been fully investigated in a thorough, quantitative, systematic fashion yet. Part of this is because our needs and preferences are as complex and varied as our subjects!

Charles Krebs · Post by **Charles Krebs** » Fri Dec 25, 2009 12:06 am

I wrote...

There's a pdf here that compares the "diffusion" of the various Lee materials.

And then didn't post the link

... here it is:

http://www.leefilters.com/downloads/##### ... Poster.pdf

DQE... sounds like the Lee Diffusion "pack". Twelve different 12x12 inch pieces for about $20.