View Full Version : DOF without camcorder zoom


Lea Lisa
February 7th, 2006, 01:13 PM
Hi!

Is it technical possbible to build a 35mm adapter that dosent require the so much camcorder zoom? -i have the Letus Flip adapter on a VX2000 and must zoom in pretty much to fill the frame. It would be nice to have the DOF and do some creative "run and gun" without using the tripod all the time.

Dennis Wood
February 7th, 2006, 01:35 PM
Best bet is to use a vibrating/oscillating beattie at minimum focus distance of cam (1.6 inches in my case)....like the MPIC or a letus with a beattie in it.

Bigo Hoggins
February 9th, 2006, 09:45 AM
I have the VX2000 also and I'm considering the letus flip also. my ???? is are you happy with your purchase....

DJ Lewis
February 9th, 2006, 11:07 AM
Hi!

Is it technical possbible to build a 35mm adapter that dosent require the so much camcorder zoom? -i have the Letus Flip adapter on a VX2000 and must zoom in pretty much to fill the frame. It would be nice to have the DOF and do some creative "run and gun" without using the tripod all the time.


There are a couple of options...

a.) the ever elusive g35 from cinemek.... I do mean elusive
b.) jim laftery's very exciting go35.... soon to come out.

if you check out jim's thread on dvxuser, you can see his progress.
http://www.dvxuser.com/V3/showthread.php?t=43399

the big thing is your achromat/macro. The more power you have, the less you'll have to zoom in.

Lea Lisa
February 9th, 2006, 11:22 AM
That go35 adapter looks great ;) -but it will show upside down image?
I love the Letus Flip -the only thing that bothers me is the zooming. Could a easy soloution be to change the achromat lens in the Letus flip to a more powerful achromat??

Wayne Kinney
February 9th, 2006, 11:44 AM
This is tough to get around.

The original letus has the GG only 40mm away from the thread, the flip version, due to the mirrors has a longer light path of about 170mm, hense the need to zoom in more. I think its simply a compromise of having the flip feature

Lea Lisa
February 9th, 2006, 11:51 AM
With the basic Letus, you still have to zoom pretty much to fill the frame?
Couldnt a more powerful achromat in flip version reduce the zoom?

Wayne Kinney
February 9th, 2006, 12:09 PM
I dont think a more powerful achromat will actually enlarge the image, but only change the way you focus, but Quyen can answer that better.

Are you concerned with the extra light loss of zooming in?

Lea Lisa
February 9th, 2006, 12:16 PM
Not really, it is more about using the camera handheld instead of using tripods. And with the necessary zoom (about 50-60%) it is impossible to shot handheld..

Wayne Kinney
February 9th, 2006, 12:26 PM
Right I see,
Well, to be honest, I dont think a stronger macro or achromat will help you out, as it will just be doing what your zoom is already doing.

The problem is the fact that the 35mm image is physically 170mm away from your camcorder, so any slight wobble is magnified the further away from the camcorder the image is. A macro wont help you out here, as once you frame up on the 35mm image, you will still be at the same distance have the same amount of wobble.

DJ Lewis
February 9th, 2006, 03:40 PM
Thanks for clearing things up Wayne... very informative :)

Andrew Todd
February 9th, 2006, 03:45 PM
why cant you do handheld? i just got my letus35 to use with an xl1s.. used it for the first time today and love the results.. i havent even tried it on a tripod yet.. all handhel and i have no complaints. why would the way you're using your camera make any difference? You would zoom in the same and not touch the zoom again...

Marcus Marchesseault
February 9th, 2006, 04:31 PM
Lea, are you keeping the Steadyshot activated while using the 35mm adapter? This could be the cause of your unsteadiness. With a 35mm adapter, the Steadyshot is reversed which causes it to make the image worse instead of better. The amount of zoom on the camcorder lens is totally irrelevant in regards to the image stability when using a 35mm adapter.

Wayne Kinney
February 9th, 2006, 04:39 PM
The amount of zoom on the camcorder lens is totally irrelevant in regards to the image stability when using a 35mm adapter.

Thats assuming there is no play in the connection between the camcorder and adapter.

Since the adapter is connected via the camcorder filter thread, and this being the adapters only support, there is a lot of leverage on the threads.

Now, image a line running down the optical centre from the camcorder through to the SLR lens. The further down this line you go towards the SLR, the more pronounced any 'wobble' is going to be. The ground glass in the flip version happens to be futher down the optic path, hense probably more prone to picking up the slightest of wobble. The answer is ofcourse a support system.

Lea Lisa
February 10th, 2006, 02:31 AM
Oupps! -forgot to turn off the stedycam -what a difference! -Now i can shot handheld without the wobbling picture. I have a Manfrotto TELE Support 293
which works great for stability.
But it would so wonderful if i only had to zoom in about 10-20% instead of 50-60%.

Bob Hart
February 10th, 2006, 11:49 AM
Lea.

The limiting factors seem to be the combination of the camera optics you are stuck with in the VX2000 as with all cams which have the non-removable lens systems plus the small size of the object we are looking at, the 35mm motion picture image frame of 24 x 18mm or slightly larger for the still-camera image frame.

What we are doing with these cams is actually a workaround.

In my tests with the PD150, which is optically much the same as the VX2000, I used several close-up lenses for relays.

One enabled me to couple a groundglass within 18mm of the front of the relay lens. Zoom-in needed was about 70%.

Another enabled me to couple a groundglass within about 200mm of the front of the lens. It still required about 70% zoom-in

The Century Optics +7 achromatic dioptre which I eventually settled on for the prism version enables a couple to the groundglass within about 120mm of the front of the lens. Zoom-in still has to be about 70%.

What lenses are you using on front of your Letus?

Lea Lisa
February 12th, 2006, 02:16 AM
I´m using FD 50mm 1.2 / 1.4 and 24mm 2.0. Now without steadycam on, it work pretty good handheld. I also succeeded to remove bad dust particles on the Flip mirrors with blowing "Air on can" ;) . I will hook up the adapter today with my GS400 and see how that works. Thanks!