DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Alternative Imaging Methods (https://www.dvinfo.net/forum/alternative-imaging-methods/)
-   -   XL2 + MIni 300 series problem (https://www.dvinfo.net/forum/alternative-imaging-methods/40354-xl2-mini-300-series-problem.html)

Asa Phelps March 1st, 2005 02:14 PM

XL2 + MIni 300 series problem
 
Hello everybody,
I have a problem with my new Canon XL2 and my Mini 35 300 series, happily used since now with an XL1.
I can see the center of the ground glass spinning! A small spinning circle exactly in the center of any image is very discernible, also with my Nikons at 1,4.
I know in the 400 series the problem has been solved, but would like to know if there is anything to do with 300 series.
Maybe in post?

The XL2 more resolution may be the problem?

Thanks for any help

Rabi Syid March 1st, 2005 05:24 PM

I can't really help but I am planning on getting the same setup as you (xl2 pal?) If you do get it to work could you post some footage.

Thanks

Samuel Smith March 2nd, 2005 02:18 AM

Same Problem
 
I just got the same set-up and am having the same problem. I spoke to a tech a ZGC and he said that the issue was that I wasn't using enough light. After testing the camera outside, in daylight, the same problem occurred (It was so bright that I had to stop down on the mini-35).

My theory is that if the glass were spinning faster it would help with the issue. The tech at ZGC said that the 300 series' spinning was slowed down to minimize noise. I use shotguns, so spinning noise isn't an issue for me. The tech is contacting Germany to find out how to increase the RPM's. I don't know if it will fix the problem, but it should help.

Any advice or suggestions would be greatly appreciated. I can't use this setup until the problem is resolved, (and I've got lots of projects on the burner :)

J.F. Villa March 11th, 2005 01:45 AM

Spinning
 
There are a few things that can be going wrong and a few things that can be done to correct the problem.
Now, you have to look at the 300 as a car without all the bells and whisles. It doesn't have anti- lock braks and you have to roll down the windows by hand. Yet in knowing it's limitations, you can still drive it safely, just as long as you are aware of them.

If you see the spinning of the crystal it might just be old and dirty. Sometimes, oil spots form on the inside of the lens. Imposible to get to without "craking it open" and cleaning them. Always have someone know what there doing touch it in a clean room.

Try fiddling around with the apture on the relay in combination of the apture on you lens. Plus you should always be on full manual mode when using the canon. Play around with the "shutter" speed.

Always put it on high rotation

In full, "play with it." I'm using an Xl1s in combination with Ziess 1.4 and nikon lenses. It differnt for each lens. And like always try writing down when you find sucsesses and note you failures


Good luck!

Soeren Mueller March 12th, 2005 11:02 AM

Hi!

Have a look at this thread:

http://www.dvinfo.net/conf/showthrea...r=3#post283206

Seems that the DoP of that promo vid had the same problem (used the same problematic Mini35 version which I was informed shouldn't be rented out any more - although in this case it seems this isn't completely true ;o)

It's kind of "funny" to see this artefact (the circle/ring) on air on all the german music tv channels currently (when they run the vid). ;-)

Dennis Hingsberg March 13th, 2005 10:10 AM

I may be able to offer some advise, or at least describe my settings since I the XL2 and series 300 mini 35. My lenses are mainly 1.4 which I never set above 5.6. I also use ND's so that my relay lens iris never exceeds 2.5 to 3.

I've shot a 20 minute short film which won best photography at the Toronto Academy of Design, a BMW spec commercial and now working on a new film with the equipment outlined above and have never managed to get spinning glass?

Some of short snips of these works can be seen under my reel section of my site.

Asa Phelps March 13th, 2005 02:42 PM

I have been able to solve the problems cleaning the ground glass with a small air pump: probably a slightly bigger particle of dust located near the centre of GG was noticeable when spinning.
I always use the Nikons at full aperture, 1.2 the 50mm and 1.4 the 85mm and 35mm.
I'm satisfied now with the results even though would be nice to have a follow focus on the nikons..

Asa

Radek Svoboda March 27th, 2005 08:04 AM

What is difference between 300 and 400 adaptors?

Dan Diaconu March 27th, 2005 08:51 AM

In the 300 series, the GG describes a circular motion around its center (as you would rotate a "pola" on the lens.... only faster).
The 400's GG describes a circle also but moving the whole GG instead (think a steam locomotive wheel actuator)

Dennis Hingsberg March 27th, 2005 09:41 AM

With the 300 series the 35mm prjoected image from the lens hits a circular ground glass which spins around and around. The image projected onto the glass is then picked up by the video camera CCD.

With the 400 series the glass vibrates/oscillates instead or rotating. The result are more random like ground glass patterns on the final image recorded to CCD and thus there is no spinning "vortex" seen in the center of the glass under certain shooting conditions.

If you keep your aperature between f5.6 and fully open you will not pick up the ground patterns on the glass. If you think this might be an issue then you should go for the newer 400 series.

If you're interested in purchasing a mint condition used mini35 series 300 please contact me and let me know. Thx.

Radek Svoboda March 27th, 2005 02:27 PM

The 400 series has the same motion as Pro 35? Could it be used on true HD cameras like Varicam and HDCAM?

Jason Brunner March 28th, 2005 04:01 PM

>>The 400 series has the same motion as Pro 35? Could it be used on true HD cameras like Varicam and HDCAM?<<

Not without some serious reverse engineering.

Different camera chip sizes, flange focal distances, and mounts, just to begin with. Even if it was technicaly feasible, for most users, the amount of time, research, engineering and money involved would negate any cost savings over just buying or renting the Pro version, which was designed from the beginning to work with those cameras.

Toby Watson March 29th, 2005 06:57 AM

mate, just throw in as many ND filters in the mattebox till you can set your aperture at around 2/2.8. That's the quickest fix i can think of.


All times are GMT -6. The time now is 11:08 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network