Finally we did it...

Dan Diaconu · June 6th, 2005, 04:38 PM

Quote:

Originally Posted by Daves Spi

Just trying to find the limits...

Good luck! I did not find them!
(now.... where did I left them? dam' limits and dam' glases... can't find a thing here.... hehehe(;-)<

Daves Spi · June 12th, 2005, 02:16 PM

Ok, lets say they are too high to care about... ;-)

Take a look here to find some footage. Tilt, Pan, Detail and Focus... All included. Shooted at 8pm...

EDIT:

This is one of last footage for dvinfo... I think, you can see huge progress till start of this thread...

I will probably film some models this week and make some music clip as final celebration, so if it will happen, I will post it here.

Good luck to everyone with waxing, rotating, oscilating, scratching or whatever to get 35mm image. Wish you your adapter fills your idea and meets you requirements...

I have to move forward to next milestone...

Daves Spi · June 14th, 2005, 03:06 PM

Everyone is hunting some Fstops or what... I do not know how to count the right number, but I've tried this :

I choosed white calendar as testing scene. I always shoot just the whole calendar, no more, no less...

With adapter:
Primary lens Takumar at 70mm set to F4 iris, AE showed F3.2 on camcorder

Without adapter:
AE showed F4 on camcorder

How to count right numbers ? Radek, can you help me ? Thanks...

Oscar Spierenburg · June 14th, 2005, 05:15 PM

What I did is let the camcorder auto expose (or something like that) and see ho many F stops it is. Than shoot the same thing with the adapter at open aperture, auto expose the DV and see ho may stops it needs now. Am I right?
Your footage seem to have a lot of light...2 stops?

Dan Diaconu · June 14th, 2005, 06:14 PM

(for all testing, camcorder @1/60):
If the camcorder "reads" in AE say... 4 (iris) for a certain scene, than with the converter (and lens wide open-which ideally should be 1.2, hehehe....) close the iris on the SLR lens till the camcorder "reads" again 4. If the SLR has a 1.4 (as max), the camera should have at least the same reading through the Fresnel and the lens @1.4 as all by itself.
Daves, if you only lose 1/2 stop due to max 4 on your Takumar, imagine how sweet life would be using a brighter lens...........

Leo Mandy · June 14th, 2005, 06:53 PM

So when you say the camcorder - you mean the camcorder without anything at all, right?

Daves Spi · June 15th, 2005, 01:23 AM

Quote:

Originally Posted by Dan Diaconu

Daves, if you only lose 1/2 stop due to max 4 on your Takumar, imagine how sweet life would be using a brighter lens...........

I can test it on 50mm with F2... So no matter how much mm is the lens (if I keep same scene in viewfinder) ? I do not understand exactly :(
I am surprised, that I got same scene at F4 without and F3.2 with. What about the F4 of takumar ? Where is this number ? I expect something like this : If I have F11 by naked camera, I should have F11-F4(of takumar)-F?(by convertor)=~F6 ;-) I know its probably rubish, but I do no know too much lens... But there must be something about the takumars F4, right ?
F-stops means what ? Count of the stops between two Iris setups, or the result after subtraction between them ?

Dan Diaconu · June 15th, 2005, 09:27 AM

Your lens iris (Takumar or anything else) will limit the amount of light that reaches the screen thus camcorder's lens. The brighter the lens you use (2 or even brighter like 1.4) the more light will end up on the screen and be captured by camcorder.
Do this test:
Set the iris on that 50mm at 8 and take a reading on the camcorder. Let's say the camcorder reads 2. Now, open the iris at 2 (on the SLR) and take another reading. it should proportionally close down and give you a reading of about 8.
Between each stop (from 4 to 5.6, from 11 to 16 and so on...) the light doubles (up or down) on both lenses (SLR and camcorder) So when you open one lens one stop you allow TWICE the light through the lens, so... the other lens will close down one stop (to compensate and give you the same amount of light)
Now, if you make available A LOT OF LIGHT (to begin with) using a FAST lens (Max aperture 1.4) then you can shoot scenes at nigh without any problems...
Look at this lens:
http://www.azfoto.cz/_web/_muzeum/le...68_lens%5D.jpg
and what it does:
http://www.alaska.net/~rowlett/noctilux.htm
Goggle for "noctilux" if you want more, but...do not search for price (or you might get depressed)

Oscar Spierenburg · June 15th, 2005, 10:20 AM

I got a 1.4 in stead of 1.7 for my wax-adapter. It's very rewarding to get as much light as possible.

Daves Spi · June 15th, 2005, 01:29 PM

Quote:

Originally Posted by Dan Diaconu

Do this test:
Set the iris on that 50mm at 8 and take a reading on the camcorder. Let's say the camcorder reads 2. Now, open the iris at 2 (on the SLR) and take another reading. it should proportionally close down and give you a reading of about 8.

Yes, but I am still mising the point :(

OK... I did this - I took Takumar 1:4 at 70mm and get this numbers :

Camera : Takumar
F11 : F4
F11 : F5.6
F6.8 : F8
F4.8 : F11
F2.8 : F16
F2.4 : F22
F1.6 : F32

But if we are talking about "loosing some F-stops", how do I get this number ?

Just to compare naked camere against camera with 35mm make me sense... What I do not understand is, how can I loose 0.5 Fstop, when I'm using F4 in front of... Hm... going in circles aroun the right point of sense :/

Oscar Spierenburg · June 16th, 2005, 08:51 AM

I think that what you should be interested in, is how much F stops you loose on the camcorder using the adapter under optimal conditions (your best lens, biggest aperture etc.)
I made this side by side for the wax glass: http://s01.picshome.com/4b4/dv-wax.jpg
Lets say the one without the adapter was 4 stops (on the camcorder) and the one with the adapter was 2 stops. So I loose two stops in this case.
Maybe I'm wrong, but this makes sense to me. With bright sunlight I also loose 2 stops, but because you get so much more tonal range on the GG, I make it 1 stop to make it brighter.

Daves Spi · June 16th, 2005, 09:01 AM

Quote:

Originally Posted by Oscar Spier

I think that what you should be interested in, is how much F stops you loose on the camcorder using the adapter under optimal conditions (your best lens, biggest aperture etc.)

In fact not me, but lots of people cares about this, so I just wanted ty try it out...

Quote:

Originally Posted by Oscar Spier

Lets say the one without the adapter was 4 stops (on the camcorder) and the one with the adapter was 2 stops. So I loose two stops in this case.
Maybe I'm wrong, but this makes sense to me. With bright sunlight I also loose 2 stops, but because you get so much more tonal range on the GG, I make it 1 stop to make it brighter.

Yes, I uderstand it same way. But if I tryied it, it showed me F4 without adapter and F3.2 with adapter and same scene (FOV). I have in front of Primary lens with F4... So, what I do not understand is, how can I get F3.2 from F4 if I put GG and next F4 in front of it... (both scenes were at 1/50s).

Dan Diaconu · June 16th, 2005, 09:22 AM

Quote:

Originally Posted by Daves Spi

Just to compare naked camere against camera with 35mm make me sense... :/

Do it then. (use that 1.8/50 this time).
Your previous test proves only the compensation between apertures settings on the two lenses : SLR and camcorder. Now...where did I put that half-a-stop?(;-)<

Bill Porter · June 18th, 2005, 09:27 AM

Quote:

Originally Posted by Daves Spi

Just to compare naked camere against camera with 35mm make me sense...

No, it does not work that way.

Quote:

Originally Posted by Daves Spi

What I do not understand is, how can I loose 0.5 Fstop, when I'm using F4 in front of...

There is no correlation between the aperture rating or setting on the SLR lens and the camcorder lens.

Quote:

Originally Posted by Daves Spi

I am surprised, that I got same scene at F4 without and F3.2 with. What about the F4 of takumar ? Where is this number ?

The reason you got F3.2 with the adapter is the camcorder opened its aperture to admit more light, to make up for the loss of light due to having an adapter and a lens in front.

Quote:

Originally Posted by Daves Spi

I expect something like this : If I have F11 by naked camera, I should have F11-F4(of takumar)-F?(by convertor)=~F6 ;-)

Nope, it doesn't work that way. The F-stop rating of each lens is a ratio of focal length to aperture, *for that lens*. You cannot add and subtract these ratings between lenses because they only describe the ratio for each lens, length vs. diameter.

Quote:

Originally Posted by Daves Spi

But there must be something about the takumars F4, right ?

Nope! :-)

Quote:

Originally Posted by Daves Spi

F-stops means what ? Count of the stops between two Iris setups, or the result after subtraction between them ?

Neither. Again, it is a ratio for one lens, to describe the aperture size of that lens.

Quote:

Originally Posted by Daves Spi

OK... I did this - I took Takumar 1:4 at 70mm and get this numbers :

Camera : Takumar
F11 : F4
F11 : F5.6
F6.8 : F8
F4.8 : F11
F2.8 : F16
F2.4 : F22
F1.6 : F32

But if we are talking about "loosing some F-stops", how do I get this number ?

You showed the number right there. It is not a simple numeral, it is a *step* in a logarhythmic progression.

The key to understanding f-stop progression is the knowledge that each successive f-stop increases logarithmically by the square root of 2 (i.e. 1.4)
.
f1.0 f1.4 f2.0 f2.8 f4.0 f5.6 f8.0 f11.0 f16.0 f22.0

Note the doubling/halving relationship between each alternate number:

f1.0......f2.0......f4.0......f8.0......f16.0
......f1.4......f2.8......f5.6......f11.0*......f22.0

* by convention, f11.2 is rounded down to f11, and similarly, f128 to f125.

Bill Porter · June 18th, 2005, 09:32 AM

Quote:

Originally Posted by Dan Diaconu

(for all testing, camcorder @1/60):
If the camcorder "reads" in AE say... 4 (iris) for a certain scene, than with the converter (and lens wide open-which ideally should be 1.2, hehehe....) close the iris on the SLR lens till the camcorder "reads" again 4. If the SLR has a 1.4 (as max), the camera should have at least the same reading through the Fresnel and the lens @1.4 as all by itself.
Daves, if you only lose 1/2 stop due to max 4 on your Takumar, imagine how sweet life would be using a brighter lens...........

I also think there is some confusion due to a typo or mistake here. If the camcorder reads F4 with no adapter in a given situation, then with the adapter and SLR there is no way you can close the iris on the SLR until the camcorder reads again F4. The more you close the SLR, the more the camcorder will open its iris, thus reading a lower number, not the other way around. Dave's tests demonstrate this nicely for me to cut and paste:

His Camera : His Takumar
F11 : F4
F11 : F5.6
F6.8 : F8
F4.8 : F11
F2.8 : F16
F2.4 : F22
F1.6 : F32

June 12th, 2005, 02:16 PM	#92
Daves Spi Regular Crew Join Date: Feb 2005 Location: Czech republic, Prague Posts: 159	Ok, lets say they are too high to care about... ;-) Take a look here to find some footage. Tilt, Pan, Detail and Focus... All included. Shooted at 8pm... EDIT: This is one of last footage for dvinfo... I think, you can see huge progress till start of this thread... I will probably film some models this week and make some music clip as final celebration, so if it will happen, I will post it here. Good luck to everyone with waxing, rotating, oscilating, scratching or whatever to get 35mm image. Wish you your adapter fills your idea and meets you requirements... I have to move forward to next milestone... __________________ Daves At the beginning there was an idea, then the ambition came and the idea became to be a dream... The Satisfied Dream => http://film.datriware.com Last edited by Daves Spi; June 13th, 2005 at 06:00 AM.

June 14th, 2005, 03:06 PM	#93
Daves Spi Regular Crew Join Date: Feb 2005 Location: Czech republic, Prague Posts: 159	Everyone is hunting some Fstops or what... I do not know how to count the right number, but I've tried this : I choosed white calendar as testing scene. I always shoot just the whole calendar, no more, no less... With adapter: Primary lens Takumar at 70mm set to F4 iris, AE showed F3.2 on camcorder Without adapter: AE showed F4 on camcorder How to count right numbers ? Radek, can you help me ? Thanks... __________________ Daves At the beginning there was an idea, then the ambition came and the idea became to be a dream... The Satisfied Dream => http://film.datriware.com Last edited by Daves Spi; June 16th, 2005 at 09:04 AM.

June 14th, 2005, 05:15 PM	#94
Oscar Spierenburg Major Player Join Date: Jan 2005 Location: (The Netherlands - Belgium) Posts: 735	What I did is let the camcorder auto expose (or something like that) and see ho many F stops it is. Than shoot the same thing with the adapter at open aperture, auto expose the DV and see ho may stops it needs now. Am I right? Your footage seem to have a lot of light...2 stops?

June 14th, 2005, 06:14 PM	#95
Dan Diaconu Major Player Join Date: Dec 2004 Location: Vancouver, Canada Posts: 804	(for all testing, camcorder @1/60): If the camcorder "reads" in AE say... 4 (iris) for a certain scene, than with the converter (and lens wide open-which ideally should be 1.2, hehehe....) close the iris on the SLR lens till the camcorder "reads" again 4. If the SLR has a 1.4 (as max), the camera should have at least the same reading through the Fresnel and the lens @1.4 as all by itself. Daves, if you only lose 1/2 stop due to max 4 on your Takumar, imagine how sweet life would be using a brighter lens...........

June 14th, 2005, 06:53 PM	#96
Leo Mandy Major Player Join Date: Dec 2004 Posts: 749	So when you say the camcorder - you mean the camcorder without anything at all, right?

June 15th, 2005, 09:27 AM	#98
Dan Diaconu Major Player Join Date: Dec 2004 Location: Vancouver, Canada Posts: 804	Your lens iris (Takumar or anything else) will limit the amount of light that reaches the screen thus camcorder's lens. The brighter the lens you use (2 or even brighter like 1.4) the more light will end up on the screen and be captured by camcorder. Do this test: Set the iris on that 50mm at 8 and take a reading on the camcorder. Let's say the camcorder reads 2. Now, open the iris at 2 (on the SLR) and take another reading. it should proportionally close down and give you a reading of about 8. Between each stop (from 4 to 5.6, from 11 to 16 and so on...) the light doubles (up or down) on both lenses (SLR and camcorder) So when you open one lens one stop you allow TWICE the light through the lens, so... the other lens will close down one stop (to compensate and give you the same amount of light) Now, if you make available A LOT OF LIGHT (to begin with) using a FAST lens (Max aperture 1.4) then you can shoot scenes at nigh without any problems... Look at this lens: http://www.azfoto.cz/_web/_muzeum/le...68_lens%5D.jpg and what it does: http://www.alaska.net/~rowlett/noctilux.htm Goggle for "noctilux" if you want more, but...do not search for price (or you might get depressed)

June 15th, 2005, 10:20 AM	#99
Oscar Spierenburg Major Player Join Date: Jan 2005 Location: (The Netherlands - Belgium) Posts: 735	I got a 1.4 in stead of 1.7 for my wax-adapter. It's very rewarding to get as much light as possible.

June 16th, 2005, 08:51 AM	#101
Oscar Spierenburg Major Player Join Date: Jan 2005 Location: (The Netherlands - Belgium) Posts: 735	I think that what you should be interested in, is how much F stops you loose on the camcorder using the adapter under optimal conditions (your best lens, biggest aperture etc.) I made this side by side for the wax glass: http://s01.picshome.com/4b4/dv-wax.jpg Lets say the one without the adapter was 4 stops (on the camcorder) and the one with the adapter was 2 stops. So I loose two stops in this case. Maybe I'm wrong, but this makes sense to me. With bright sunlight I also loose 2 stops, but because you get so much more tonal range on the GG, I make it 1 stop to make it brighter.