[DAZZZLA]

This calculator can be used to estimate various combinations of components in a projector.
The units can be changed by clicking on them. (mm, M, inches and Feet)
To find a certain value click on the checkbox next to the textbox and it will turn green. By changing one of the other textboxes the green selected textbox will display the result. For example if you have a 15” LCD and a 320mm FL triplet and you want to get a 100” screen then click the screen distance checkbox to turn it green then change the screen size to 100”. The green screen distance textbox will give you the required distance that the triplet will need to be from the screen. Or you might want to see how much bigger a 17” LCD would make the screen than a 15” LCD at the same distance. Select the screen size checkbox and then change the LCD size from 15” to 17”.

The FL of the triplet as a rule of thumb can be considered at the centre of the lens but this is not always the case. It all depends on the various elements in the triplet; it could be closer to the rear or closer to the front of the lens.

The value that is entered in the LCD size textbox will be the same type as the screen size textbox or vis versa. For example if you enter the LCD diagonal the result in the screen size textbox will also be diagonal. If you enter the LCD width then the screen textbox will also be width.

Warnings and messages:
If you enter a value in a textbox that can’t be used by the calculator then all other textboxes will turn red to indicate that a result is not possible. For example a zero value will cause an error. A message will pop up in the bottom right corner to indicate other types of errors. If in split then entering a value into the triplet FL that is less then the gap will cause an error because the triplet can’t be moved any closer than the physical position of the front fresnel.
You will probably notice that the labels above each textbox may sometimes turn red; this is just a warning that the value in that particular textbox is larger than what is being displayed. Use the arrow keys if you want to see the entire value.

Let me know if you find any bugs.
Please enjoy.

DJ

Bugs:
If you get a “Runtime Error ‘13’ Type Mismatch” message you will need to go into Regional And Language options in XP and choose English

Attached File(s)

•  focalcalc143.zip (82.4K)
  Number of downloads: 19827

This post has been edited by DAZZZLA: 06 February 2008 - 06:26 AM

[yoshuaspawn]

Hey DAZZLA,
Is there a (free)way to use this on a mac?
Thanks in advance for any advice.

[mikez0r]

yoshua, if you have OS X, you might try the wine project. It's a windows emulator, sort-of, for unix and its relatives, and I think it would work also under OS X.

EDIT: I forgot the link...

http://www.winehq.com

This post has been edited by mikez0r: 23 February 2006 - 06:15 PM

[yoshuaspawn]

mikez0r, on Feb 22 2006, 02:18 PM, said:

yoshua, if you have OS X, you might try the wine project. It's a windows emulator, sort-of, for unix and its relatives, and I think it would work also under OS X.

EDIT: I forgot the link...

http://www.winehq.com

Thank you

[Fulcrum]

Dazzzla,

This calculator is AWESOME! The theory is finally making sense to me, as I'm able to play with the focal numbers and determine what has the greatest effect to my intended output. You really did a terrific job!

Is it, however, possible to get the field outputs limited to two decimals? If not, that is OK, it would just makes it easier to revise the numbers when inputted, (especially if your jumping around from field to field like me).

All in all this is the best tool I have used. Being able to switch from Split and Unsplit Optics, while keeping the same numbers in place is a nice feature for comparison sake. And being able to switch to the different fields for review, has helped me explore other available options that I had not even considered.

Just an all around GREAT JOB!

Fulcrum

[DAZZZLA]

Fulcrum, on Apr 14 2006, 02:32 PM, said:

Dazzzla,

This calculator is AWESOME! The theory is finally making sense to me, as I'm able to play with the focal numbers and determine what has the greatest effect to my intended output. You really did a terrific job!

Is it, however, possible to get the field outputs limited to two decimals? If not, that is OK, it would just makes it easier to revise the numbers when inputted, (especially if your jumping around from field to field like me).

All in all this is the best tool I have used. Being able to switch from Split and Unsplit Optics, while keeping the same numbers in place is a nice feature for comparison sake. And being able to switch to the different fields for review, has helped me explore other available options that I had not even considered.

Just an all around GREAT JOB!

Fulcrum

Thanks.
Unfortunately I can’t reduce the decimal places easily.

DJ

[Fulcrum]

DAZZZLA, on Apr 14 2006, 03:55 AM, said:

Thanks.
Unfortunately I can’t reduce the decimal places easily.

DJ

It is still an EXCELLENT spreadsheet. For a while I was not sure if I should buy the 550 or 650 fresnel to go with my 18 inch opaque triplet. NOW I KNOW that either will work, but the LL 650 fresnel will probably work better as suggested by others.

Great Job!

Fulcrum

[darbronnoco]

Thanks for the great program. I had an idea that may be a nice simple extra. I was wondering if you could have a radio check fro the different standard triplets ie the pro and standard lens. I may save some people time for looking that up in the forms and could be useful for people trying to decide on a setup. Thanks again.

Brad

[nitsua]

Hi DAZZZLA, great program, but please please spend some time on that regional setting bug.. it's really quite annoying to keep changing the regional settings on my own pc, and i cant even change the regional settings on the computers on my faculty, wich makes the program unusable over there..

This post has been edited by nitsua: 24 May 2006 - 04:50 PM

[DAZZZLA]

nitsua, on May 25 2006, 01:49 AM, said:

Hi DAZZZLA, great program, but please please spend some time on that regional setting bug.. it's really quite annoying to keep changing the regional settings on my own pc, and i cant even change the regional settings on the computers on my faculty, wich makes the program unusable over there..

The latest version shouldn't raise this error anymore. I tried a few different nationalities and it seems to be working let me know how it goes.

DJ

[Ruhkande]

Thanks for the tool! I have a question though. When referencing the LCD size and projection size, is it referring to the diagonal or the width? I would guess the diagonal, just making sure.

Thanks again,

Ruhk

[DAZZZLA]

Ruhkande, on May 27 2006, 07:07 AM, said:

Thanks for the tool! I have a question though. When referencing the LCD size and projection size, is it referring to the diagonal or the width? I would guess the diagonal, just making sure.

Thanks again,

Ruhk

The value that is entered in the LCD size textbox will be the same type as the screen size textbox or vis versa. For example if you enter the LCD diagonal the result in the screen size textbox will also be diagonal. If you enter the LCD width then the screen textbox will also be width.

[nitsua]

DAZZZLA, on May 25 2006, 02:41 AM, said:

The latest version shouldn't raise this error anymore. I tried a few different nationalities and it seems to be working let me know how it goes.

DJ

Great DAZZZLA, I think it IS working now. I have to try it on my work as well, but at least here all go's smooth

[bobtannica]

Thank you for the great program it has simplified many things in my project. I do have one question though - re the split fresnel configuration: which fresnel is it seeking the focal length of? Thanks.

[komair]

hi! this is a really neat program! just one question. in the split mode what are the units of Virtual LCD Height, Virtual LCD Distance and also, what do these number represent? Thanks!

[DAZZZLA]

komair, on Jul 2 2006, 12:31 AM, said:

hi! this is a really neat program! just one question. in the split mode what are the units of Virtual LCD Height, Virtual LCD Distance and also, what do these number represent? Thanks!

The virtual LCD height should really be called just virtual LCD, I’ll fix that the next time I update it.
The front fresnel magnifies the LCD so it appears larger than it actually is. If you look though a lens at your hand it will appear larger to your eye. The fresnel does the same thing to the LCD and the triplet takes the place of your eye.
The virtual LCD height is the size of the LCD that the triplet is focusing on through the front fresnel. The virtual LCD distance is how far back the LCD appears to the triplet through the front fresnel. The fresnel magnification is the ratio between the actual LCD size and the virtual LCD size.

DJ

[samsagaz]

DAZZZLA, on Jul 1 2006, 06:16 PM, said:

The virtual LCD height should really be called just virtual LCD, I’ll fix that the next time I update it.
The front fresnel magnifies the LCD so it appears larger than it actually is. If you look though a lens at your hand it will appear larger to your eye. The fresnel does the same thing to the LCD and the triplet takes the place of your eye.
The virtual LCD height is the size of the LCD that the triplet is focusing on through the front fresnel. The virtual LCD distance is how far back the LCD appears to the triplet through the front fresnel. The fresnel magnification is the ratio between the actual LCD size and the virtual LCD size.

DJ

if i want to hand made do the calcs. How i do it? where can i get the "formula" for that?

[nilesh]

thank you very much for post useful information
it so useful to calculate with somne certain data
thanks again

[Banana Man]

Great program. I downloaded a rev1.43 and it has a bug however. If you go to split, select the screen size radio button, and then put 8 feet in the screen distance, I get .0289771... feet. When I try to select this textbox and scroll left, there are no more digits to show. I suspect the the display buffer overflows with all the decimal digits. What language did you write this in. I may be able to help. Otherwise its a great tool. Thanks alot!


BM

[DAZZZLA]

Banana Man, on Sep 24 2006, 11:59 PM, said:

Great program. I downloaded a rev1.43 and it has a bug however. If you go to split, select the screen size radio button, and then put 8 feet in the screen distance, I get .0289771... feet. When I try to select this textbox and scroll left, there are no more digits to show. I suspect the the display buffer overflows with all the decimal digits. What language did you write this in. I may be able to help. Otherwise its a great tool. Thanks alot!
BM

Thanks for the bug report.
It’s written in VB and the problem happens because text boxes aren’t really good at dealing with numbers especially with open-ended algorithms. I will get around to re-writing it eventually .

DJ

[rhubbard]

Is there anyone who can pass on a MAC OSX version or the raw formula so I don't have to download "wine HQ" or something similar?

Thanks, I appreciate it!

[vonneuton]

rhubbard, on Sep 28 2006, 02:21 AM, said:

Is there anyone who can pass on a MAC OSX version or the raw formula so I don't have to download "wine HQ" or something similar?

Thanks, I appreciate it!

Here's a link on this board for a PHP focal calc - should work in your web browser:

PHP Focal Calc

[rhubbard]

FANTASTIC.

thanks!

[webster]

DAZZZLA, on Jul 1 2006, 01:16 PM, said:

The virtual LCD height should really be called just virtual LCD, I’ll fix that the next time I update it.
The front fresnel magnifies the LCD so it appears larger than it actually is. If you look though a lens at your hand it will appear larger to your eye. The fresnel does the same thing to the LCD and the triplet takes the place of your eye.
The virtual LCD height is the size of the LCD that the triplet is focusing on through the front fresnel. The virtual LCD distance is how far back the LCD appears to the triplet through the front fresnel. The fresnel magnification is the ratio between the actual LCD size and the virtual LCD size.

DJ

Great calculator! I'm interested in the math behind the split version. Any chance you could explain the calculations?... to get a better understanding I'd like to be able to the math myself at least once. I think I have a grip on the virtual image/object projected by the fresnel...my trouble may be the math going through the triplet. Cheers.

This post has been edited by webster: 24 October 2006 - 02:44 PM

[computercowboy]

if you run this on windows server 2003 or windows vista / longhorn

you will need to place msvbvm50.dll in your window/system32 directory

get it from me here http://computercowboy.biz/msvbvm50.zip
or from dll-files.com here http://www.dll-files...op.php?msvbvm50