DOF tutorial for 35mm adapter users (20 min)

Sweet! Thanks a lot. I had already known most of what was in the video but the write up on why the imaging surface size makes a difference, I didn't know. The way you laid everything out made it very simple to digest. Thanks again.
 
Hey man, I'm a newb to the boards and a newb to filming - that video was absolutely brilliant - so clear, concise and well presented. Very generous of you to hand out such useful information, thank you very much indeed.

Regards,

Leo
 
hey man. great video, but it had nothing to do with using 35mm adaptor. your quote, "I made this for a DVD that never happened. Should be helpful for those using or planning to use a 35mm adapter."

are you suggesting that if you you use 35mm cine lens, 35mm still lenes, and a 16mm cine lens with a 35mm adaptor you'll achieve the same DoF as a 35mm cine lens?

very confused,
mike
 
smoothmc40 said:
very confused,
Click to expand...

That makes two of us. I'm not exactly sure what you are asking, but I'll do my best to answer.

The DOF tutorial was originally intended to be part of an instructional DVD which guided the viewer though building their own 35mm adapter. The DVD never happened, but I had already finished the DOF tutorial and thus decided to post it instead of let it sit on my computer. The reason that the tutorial "Should be helpful for those using or planning to use a 35mm adapter" is because that is the audience for which it was originally intended.

That being said, the DOF tutorial is fitting for anyone and it is not limited to 35mm adapter users.

smoothmc40 said:
are you suggesting that if you you use 35mm cine lens, 35mm still lenes, and a 16mm cine lens with a 35mm adaptor you'll achieve the same DoF as a 35mm cine lens?
Click to expand...

The rules for DOF are the same no matter what lenses you are using. The one thing that comes into play with DOF in terms of differing format sizes (and lenses intended for different format sizes) is the maximum permissible circle of confusion. The maximum permissible circle of confusion is a part of the total DOF formula and differs between various formats.

Looking at the formula below you can see that the circle of confusion plays a role in finding the hyperfocal distance which in turn is used in finding the near and far limits of the DOF.

from [url said:
http://dvinfo.net/articles/optics/dofskinny.php][/url]
Hyperfocal Distance: h = f2 / ac

f = focal length of lens
a = aperture diameter (f/stop number)
c = circle of confusion

Depth of Field, Near limit: hs / h + (s - f)

Depth of Field, Far limit: hs / h - (s - f)

h = hyperfocal distance
s = distance from camera to object
f = focal length of lens
​
Click to expand...

This page does a nice job of giving a simple explanation of the circle of confusion.

http://tangentsoft.net/fcalc/help/CoC.htm

I hope that answered you question to some degree.
 
very informative

very informative

I don't know whether I said it, Very good tutorial to get basics and even complex stuff learned quickly. :)

thanks
 
Justin,

I have been looking at getting a 35mm adapter for myself. Very nice tutorial. I especially liked the 1/3ccd info. You are a great example of why I dig this forum, thanks!
 
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