Consolidated XL1 35mm Adapter Thread

[Stephen Birdsong]

it would probably be better to have a moderator do it.

stephen

[Aaron Rosen]

So bear with this question for a second:

Can some one tell me the benifit of the Mini 35 adaptor, Canon's or otherwise?

What would I want to use it for?

[Stephen Birdsong]

Flexibility with DOF or depth of field. One of the most noticable characteristics of dv that sets it apart from 35mm is its enourmous dof.

[Jeff Donald]

A good starting point might be getting your hands on an adapter that JVC used to make. It adapted Nikor lenses to 2/3 inch bayonet for video cameras. This was just a relay lens adapter and there was no magnification of focal lengths. You could possibly reverse engineer the adapter for use with the XL mount.

[Stephen Birdsong]

jeff, could you be more specific on how this would be of help?
whether there are optics in the adapter or not, a larger format lens will always produce what is arguably called a multiplier effect. Not sure of the acurate way to say it, but a 10mm 2/3 in will act like a longer 1/3 inch.


stephen

[Kevin Burnfield]

Patrick Wright posted this in the XL1S 'post pics of your rig' thread:

---------
Heya,

Thanks for the compliments. I really havent had time to go out
and shoot enough good examples to do a proper comparison but
weather permitting I hope to get around to doing more this weekend.

The lens is an Angenieux 9.5mm-57mm wide angle for 16mm with an Arri style
Bayonet mount http://www.quicktel.com/users/archamian/adapter004.JPG that
has a speed range of F1.9-22 (T1.9-22). I really wanted a high quality fully
manual lens that wasn't going to cost me $1500+ and also I hoped it would give
a greater sense of DOF so I picked this one up on ebay for $350. I chose the
bayonet mount because they are plentiful and seem cheaper overall than PL or
other more modern mounts. Also they still produce new lenses with this same
mount so if I wanted a lens with modern optical coatings id have an upgrade
path. Because the lens is 16mm format the magnification (about 1.8) and loss of
DOF is much less than 35mm lenses which have magnification factor of about 7
and lose significant DOF.

The adapter itself is comprised of two main pieces. The body is made
from aircraft aluminum while the mount is a factory xl1 stainless steel
([url] http://www.quicktel.com/users/archamian/adapter005.JPG [/url) mount
you can order from Canon USA in New Jersey for $45. The adapter
body cost $400 to produce at a local machine shop though they admitted
that if they made 20+ the price would drop to about $75-$100 for the body
not counting the cost of the factory mount.

Overall I would probably have been better off just buying a manual lens that
was made for the XL1 but I am very happy with the results and the total control
this setup affords me. Also I can buy used 16mm lenses for much less and there
is a significantly wider variety of lenses to choose from now.

As for the mini35s I'm also working on an Augus35(moving) and Aldu35(static)
of my own and though I have the DOF I wanted the filmic look some are achieving
is very desirable. Yes, much of the filmic look can be achieved in post but I like to
get my footage as close as ideal as possible to reduce the amount of post work.

I hope this has answered your questions, if you have any more please email me.

--Patrick

---------------------------

Patrick is a great guy and answered all my questions so I'm sure he'd be willing to help out if any of you think this sort of thing would move us along?????

[Stephen Birdsong]

so, the benefit is: bayonnette mount would be cheaper, as would the lenses, we could just use those lenses instead of the schneider lens or 35mm slr lens?

Am i understanding this? Is this going to actually be much cheaper?

stephen

[Roger Moore]

Kevin, can you give a link for ordering the canon factory xl1 mount?

Wait, it's Patrick who ordered the mount. Could you ask him for me?

And that's a good idea using the 16mm lens.

[Chris Hurd]

Okay, just to clarify, you guys really want all of these threads merged into a single gigantic one:

http://www.dvinfo.net/conf/showthrea...threadid=33522
http://www.dvinfo.net/conf/showthrea...threadid=23451
http://www.dvinfo.net/conf/showthrea...threadid=33168
http://www.dvinfo.net/conf/showthrea...threadid=23377

Do you want a copy of each of the originals left intact, or do you just want to throw 'em all into one big pile?

[Stephen Birdsong]

I'm down with one pig pile..
One place for all the xl1 info.

stephen

[Kevin Burnfield]

I don't know Chris... that'll end up being like the 3000+ thread for the Agus and Aldus topics---

I'll go along with the concensus but I think if we copy of important posts, important information we can consolidate the information on the XL1 project.

What does anyone else think?

[Rai Orz]

It seems some people dont know DOF basics, so look at this online DOF calculator:

http://www.dofmaster.com/dofjs.html

(select for example a subject distance = 2meters and
change the focal lenght and f-stop, the effects are impressing)

To calculate, you must know the size of 35mm movie (not still) film is rounded 22 x 16mm and the Canon XL sensor is only 4,8 x 3,6 mm. This means the Sensor is round 4,6 x smaller than 35movie film (35mm still film is 36 X 24mm and for this the factor is 7,5x). So you need only change the focal length by this factor (not the film format size)

For DOF, you need more parameters: focal length and F-Stop

Because the size factor is 4,6 (compared to movie) you need a 4,6 x smaller focal length if you wont the same point of view. If you now wont the same DOF you must push the F-STOP high.

Thats why the F-Stops are verry important. But the CANON lenses have no manual IRIS, so you have no change to know what F-Stop the CAMERA have for the moment.

This is a reason why a full manual lenses is better, if you dont wont a GG solution. But if you use a manual lenses with not so good F-Stops like the original canon, you take a step backwards.

A different ideal is to modify the CANON lens with a otional manual IRIS poti. We have this made, its very simple.

[Chris Hurd]

The resulting thread would be 12 + 49 + 32 + 110 posts long, or just over 200 posts total. Long but not unmanageable compared to the Agus35 and Aldu35 threads. If you guys can reach an agreement, then I'll be happy to merge them together.

[Kevin Burnfield]

I'll leave the final decision to a consensus but for me having a 200 post long thread kinda makes it impossible to get through rather then going through and pasting over only the most important or relevant of the posts.

[Stephen Birdsong]

If we merge them, it will be no longer than if we have to go through and search through all 3 threads for an individual post, in fact, it will be faster because its all centralized. I like the idea of merging all, because anyone interested in this topic would have only 1 place to go, the active thread. If we leave the other threads open, then it still has the effect of splitting up the effort. I vote merge.

stephen