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#1 Vivek Venkatraman

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Posted 10 August 2015 - 11:35 PM

Hello,

 

So I am relatively new to lighting. I am a student cinematographer.

I would like to know anything and everything related to diffusion.

What materials give what kind of results ? [youtube links should be fine here]

What fixtures give what kind of results ?

How does size of diffusing material affect the image ?

How does distance between light , material and subject affect the image ?

How does size of light source affect the image ?

What should we look out for while using diffusion ?

Is the kind of light given by a kino already diffused ? Or is there a difference between "soft light" and diffusion ?[stupid question but please help]

The history of diffusion - When did diffusion start in the history of cinema ? etc etc

How does diffusion look when combined with bounce ? [bounce a light and then diffuse it ] ?

 

Anything else you would like to share or any other online material that is worth a read :)

 

Thank You,

 

 


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#2 Stuart Brereton

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Posted 11 August 2015 - 12:08 AM

Vivek, this a real names forum. Please contact the forum administrator to have your screen name changed to your real first and last name.

 

Secondly, most of your questions have been answered many times. Please use the search function to find old threads on these subjects.


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#3 Vivek Venkatraman

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Posted 11 August 2015 - 01:06 AM

Hey Stuart,

 

My real name is Vivek, I do not have a second name.

 

Thank you for your response.


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#4 David Mullen ASC

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Posted 11 August 2015 - 02:07 AM

It would take a very long magazine article or a large chapter in a book to answer all of those questions -- a posted reply in a forum would be inadequate.  One question alone in your list could take several replies!  

 

Since these are basic questions, you should first do some searching on your own and then come back with a few more specific questions when you find something you read confusing.

 

As for YouTube links to demos using diffusion gels for lighting, we could do some searching under various terms to find some links, but you could do the same searches on your own.

 

Your post comes off as someone who has a classroom assignment to write and wants help in writing it.

 

Some of this is common sense, like what do you think happens when you take the soft light that comes from a bounce and then diffuse it further by passing it through a diffusion material? It generally gets softer -- though you are always limited by the size of the soft source.  In other words, if you completely fill a bounce surface evenly from corner to corner with no variation in brightness across the surface, then the light can't get any softer until to becomes a larger surface, in other words, if the size of the bounce area is 12'x12' and you pass it through a 12'x12' diffusion frame, it can't get any softer if it was already a perfect soft even 12'x12' bounce.  In reality though, no bounce is perfect so passing it through a second 12'x12' diffusion frame would make it easier to fill the 12'x12' area more completely and evenly, but ultimately it is the 12'x12' size relative to the subject that determines it's softness.

 

"Diffused light" is a type of soft light, though broadly speaking, all soft light is soft because it has been "diffused" in some manner.  There are many degrees of softness to a light, from barely soft to super soft.  Now you can soften a light by passing it through a diffusing material or by bouncing it off of a material, or both, and the type of light itself may be a soft source too.

 

Just keep in mind that the general rule is that the size of the source -- and in this case when you hit a diffusion frame or bounce card with a hard light, then the diffusion frame or the bounce card is considered the source -- relative to the subject determines the sharpness or softness of the light on the subject.  "Relative" is key because you can make a 12'x12' soft light and move it farther away so that from the point of view of the subject, it is the same size in their vision as a closer 4'x4' soft light, and both lights would create shadows of the same softness, the only difference is the degree of fall-off in intensity over distance, not the degree of softness.  But all of this assumes a "perfect" diffusion surface, that light is evenly filling the diffusing surface from corner to corner, when in reality, you often have a hot spot with fall-off around the corners.

 

A good example would be when you shine a light through a 12'x12' frame of thin diffusion compared to heavy diffusion, with the thin diffusion the light would create a hot spot in the middle which is really the size of the soft light, not the 12'x12 area.  And some diffusion material allows some hard specular light to leak through the weave of the material, creating a soft light with a faint hard light mixed into it.

 

You see, I wrote all of that and I only was setting the stage to discuss soft light.  It would take a book to answer all of your questions.


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#5 Mark Dunn

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Posted 11 August 2015 - 06:04 AM

Hey Stuart,

 

My real name is Vivek, I do not have a second name.

 

Thank you for your response.

Forgive us for wondering but in a Google search for 'vivek cinematographer' yours appears to be the only result without a surname.


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#6 Vivek Venkatraman

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Posted 11 August 2015 - 06:13 AM

David

 

Thank you for the taking the time and effort to respond.

It is true that I have a classroom assignment where I need to do a brief writeup on diffusion. Is there a forum rule against asking for help in relation to assignments ?

But there are certain queries I had regarding diffusion outside of my assignment.

 

The relationship between the size of diffusion and subject to light distance was something I had not heard of before.

 

You also mentioned a certain diffusion material that allows for specular leaks of light causing a mix of hard and soft light. What is this material called ?

 

I would also love it if you could take sometime to share your thoughts on my post [titled "Script Breakdown] in the General Discussion session regarding how you approach the aesthetic choices you make as a cinematographer.

 

Thank You once again.


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#7 Vivek Venkatraman

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Posted 11 August 2015 - 06:17 AM

Mark Dunn,

 

 

I technically do not have a surname or a second name.

On my passport it is just my name followed by my fathers name.

 

Anyway I have contacted Tim Tyler regarding this, hopefully it is sorted out soon.

 

Thank You


Edited by Vivek, 11 August 2015 - 06:24 AM.

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#8 Robin R Probyn

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Posted 11 August 2015 - 07:32 AM

Mark.. there are places in the world with out surnames.. a lot of India,Indonesia ..Bhutan .. and  Iceland .. that I know of..


Edited by Robin R Probyn, 11 August 2015 - 07:32 AM.

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#9 Freya Black

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Posted 11 August 2015 - 08:52 AM

Mark.. there are places in the world with out surnames.. a lot of India,Indonesia ..Bhutan .. and  Iceland .. that I know of..

 

 

Actually Iceland have surnames, they just change as new people are born so they aren't representing a family line in the same way.

 

Also here in the UK it's not uncommon for womens surnames to change at various points in their life too which is not something that ever seems to occur to male software developers in the United States.

 

Freya


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#10 Robin R Probyn

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Posted 11 August 2015 - 09:03 AM

Don't want to split heirs :) .. but according to what a Surname means .. they don't have Surnames in Iceland .. this is the same case as the OP.. his fathers name comes after his.. but this is not a Surname..

The poor guy is reprimanded for not using his real name.. is further investigated by PC Mark Dunn.. and not an apology in sight.. where the love you,all.. 

 

 

 

"Unlike most other Western countries Icelanders do not use family names but use a patronymic or matronymic reference. One's name reflects the immediate father or mother and does not refer to the person's historic family lineage."


Edited by Robin R Probyn, 11 August 2015 - 09:07 AM.

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#11 Freya Black

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Posted 11 August 2015 - 10:01 AM

Don't want to split heirs :) .. but according to what a Surname means .. they don't have Surnames in Iceland .. this is the same case as the OP.. his fathers name comes after his.. but this is not a Surname..

The poor guy is reprimanded for not using his real name.. is further investigated by PC Mark Dunn.. and not an apology in sight.. where the love you,all.. 

 

 

 

"Unlike most other Western countries Icelanders do not use family names but use a patronymic or matronymic reference. One's name reflects the immediate father or mother and does not refer to the person's historic family lineage."

 

 

Didn't realise the definition of surname was quite so strict. I always took the meaning to be the same as the words but a quick google reveals that most definitions are very tight with it being a family name. A bit of a surprise.

 

I got the impression that maybe Vivek doesn't have a last name at all and that the Fathers name appears in the passport because some people get really upset if you can't give them a last name. I think because they feel safe with the familiar.

 

I took P.C. Dunns posting as an apology. It does begin "forgive us".

However so do many prayers I guess?

 

Freya


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#12 Stuart Brereton

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Posted 11 August 2015 - 11:47 AM

The poor guy is reprimanded for not using his real name..

I think reprimand is a bit strong. I was perfectly polite. 

 

It's a fact that many people fail to read the simple instructions when creating an account, and use only one name. There are also regular posters here using fake names (you know who you are...)


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#13 David Mullen ASC

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Posted 11 August 2015 - 12:21 PM

Stuart is right to point out that people need to register using their full name, I do it often myself too.  It was a big effort several years ago to get everyone to start signing up under a real name and I don't want to see it slip back.  Most forums at some point find that the level of trolling and personal attacks go way down when they switch to a real name policy, people act differently when they have their real name attached to the post.

 

Vivek --

 

There's no problem with asking for answers on a forum for a school assignment, but there is a problem with not doing your own research first to get basic concepts figured out; a forum is not good for teaching large chunks of information found in books, it's for fine-tuning, getting some SHORT answers on specific points where you still remain confused.

 

Any looser-weaved fabric material can allow specular light to leak through the gaps in the fabric's weave unsoftened while also creating a soft light from the fabric itself being illuminated.  Some of the lighter grades of silks for example, like a quarter silk.  Also a silk, because of the weave, will spread a point-source light in a star-shaped pattern rather than a spreading circular pattern, and that effects the texture of the soft light.

 

Half of your questions would be answered just by spending some time with a light and some diffusion materials and looking with your own eyes.  But I'm sure somewhere on YouTube someone has done some demos with diffusion techniques for lights, I'm just not going to do your work for you by searching YouTube when you can search YouTube yourself.


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#14 Robin R Probyn

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Posted 11 August 2015 - 06:29 PM

Sure I get all that..but when he pointed out that he actually didnt have a surname ..had I been the one to point out that he needed to use a real name.. and was then even googled..??? and questioned again after he had stated he only had one name.. this can only be seen as frankly, Mark not believing him and naively not knowing there are ,millions of people in the world named this way..  I think a quick  apology would have been in order from either of them... no?.. not very friendly .. 


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#15 David Mullen ASC

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Posted 11 August 2015 - 06:37 PM

People have been on this forum in the past claiming to have only one name, only for them to "discover" they had a family name after all.

 

Why should Stuart apologize for reminding him of the rules for registering under a first and last name?  He didn't do something wrong, he didn't say that Vivek was lying about it.


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#16 Robin R Probyn

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Posted 11 August 2015 - 06:42 PM

 

 

Didn't realise the definition of surname was quite so strict. I always took the meaning to be the same as the words but a quick google reveals that most definitions are very tight with it being a family name. A bit of a surprise.

 

I got the impression that maybe Vivek doesn't have a last name at all and that the Fathers name appears in the passport because some people get really upset if you can't give them a last name. I think because they feel safe with the familiar.

 

I took P.C. Dunns posting as an apology. It does begin "forgive us".

However so do many prayers I guess?

 

Freya

 

Yeah forgive us for not believing you... I believe The Spanish Inquisition .. asked for forgiveness before they asked a few questions .. 


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#17 Robin R Probyn

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Posted 11 August 2015 - 06:47 PM

well maybe its just me then.. I would thought a quick note just to say .. ok I see the situation.. you did/may have read the rules but actually only have one name.. would have been the polite way to do it.. esp after another member had taken it upon himself to actually google the poor guy, obviously not believing him..   you don't think a short apology is in order.. 


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#18 Stuart Brereton

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Posted 11 August 2015 - 07:20 PM

I'm not going to apologize to someone for having reminded them of the forum rules. Vivek says that on his passport, it has his name followed by his father's name, which as far as I can see fits into the definition of First Name, Last Name. As he's now provided that to Tim Tyler, I don't really see where an apology is necessary, and there's certainly no need for recriminations from others.


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#19 Vivek Venkatraman

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Posted 11 August 2015 - 09:42 PM

Hey,

 

David

 

I will of course do my own research and ask more detailed questions.

Thank you for your guidance.

 

Stuart and Mark

 

Let me just explain how the naming convention works in my part of India.

My fathers name is Venkatraman

My name is Vivek.

If my some were named Vivek as well, his passport would read Vivek Vivek.

Venkatraman is not my family name it is my Fathers first name.

Either way I have contacted Tim Tyler regarding this matter. 

Will take it forward with him.

 

I also understand that more then technicalities on naming conventions its about having accountability on the internet which I am all for, I love this forum and the guidance that I get from cinematographers of experience and repute. :)

 

 

 

Also since google seems to be the way to find out my name please do google Tamil surname naming conventions.

 

Sorry for the trouble.


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#20 Robin R Probyn

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Posted 11 August 2015 - 10:42 PM

I'm not going to apologize to someone for having reminded them of the forum rules. Vivek says that on his passport, it has his name followed by his father's name, which as far as I can see fits into the definition of First Name, Last Name. As he's now provided that to Tim Tyler, I don't really see where an apology is necessary, and there's certainly no need for recriminations from others.

 

Well I would have.. maybe he did read the rules and was  abiding by them ..as was the actually the  case  ! but yes agree no need for recriminations  by others .. or google searches of a guy who has already explained himself.. that deservers an apology for sure.. 


Edited by Robin R Probyn, 11 August 2015 - 10:44 PM.

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