Lens adapters and 60p recording ... at DVinfo.net
DV Info Net

Go Back   DV Info Net > Special Interest Areas > Alternative Imaging Methods
Register FAQ Today's Posts Buyer's Guides

Alternative Imaging Methods
DV Info Net is the birthplace of all 35mm adapters.

Reply
 
Thread Tools Search this Thread
Old August 27th, 2007, 01:20 AM   #1
Major Player
 
Join Date: Nov 2002
Location: Tokyo
Posts: 898
Lens adapters and 60p recording ...

I remember somewhere over the last few years comments regarding lens adapters not being able to be used when recording at 60p? Anyone have any clarifications on that. Something to do with the spin rate or shake rate of the device, me thinks.
Dean Harrington is offline   Reply With Quote
Old August 27th, 2007, 02:16 AM   #2
Regular Crew
 
Join Date: May 2005
Location: Breda, Netherlands
Posts: 141
What i heard (if ir remember it well) a rentalhouse advised me not to use the hvx in combination with the mini35 when shooting 60p because you would see the 'grain' of the spinning groundglass. I don't know the exact reasons though..
__________________
www.wanah.nl
Djee Smit is offline   Reply With Quote
Old August 27th, 2007, 06:12 AM   #3
Trustee
 
Join Date: Jun 2005
Location: Hollywood, CA
Posts: 1,675
Images: 1
As framerate increases, so does shutter speed so less motion blur is enacted. Thus the grain is caught in action instead of being blurred. The effective framerate of 60p would be 1/120 (right?) and I've definitely used adapters at this shutter speed with little issue. Spinner-design adapters should have no issue, without question. I'm not as confident about vibrating designs.
__________________
BenWinter.com
Ben Winter is offline   Reply With Quote
Old August 27th, 2007, 07:14 AM   #4
Major Player
 
Join Date: Nov 2002
Location: Tokyo
Posts: 898
thanks much ...

one of the issues with adapters, I've been thinking of going that route but would love some experience with an adapter or at least someone who has one working with an HVX to give me the low down. I agree the vibrating adapter might not work will at that frame rate. I did 24 shutter speed on 24P before and got the gladiator look, more or less. Hmmm, I wonder what 60p at 60 shutter would look like?
Dean Harrington is offline   Reply With Quote
Old August 27th, 2007, 07:43 AM   #5
Trustee
 
Join Date: Jun 2005
Location: Hollywood, CA
Posts: 1,675
Images: 1
Quote:
Originally Posted by Dean Harrington View Post
one of the issues with adapters, I've been thinking of going that route but would love some experience with an adapter or at least someone who has one working with an HVX to give me the low down. I agree the vibrating adapter might not work will at that frame rate. I did 24 shutter speed on 24P before and got the gladiator look, more or less. Hmmm, I wonder what 60p at 60 shutter would look like?
What do you mean 24 shutter? 1/24? that seems really slow...
__________________
BenWinter.com
Ben Winter is offline   Reply With Quote
Old August 27th, 2007, 07:52 AM   #6
Major Player
 
Join Date: Nov 2002
Location: Tokyo
Posts: 898
yes that's right ...

Quote:
Originally Posted by Ben Winter View Post
What do you mean 24 shutter? 1/24? that seems really slow...
choppy but interesting ~ used it in a project.
Dean Harrington is offline   Reply With Quote
Old August 27th, 2007, 10:13 AM   #7
Inner Circle
 
Join Date: Dec 2003
Location: PERTH. W.A. AUSTRALIA.
Posts: 4,477
I concur with Ben on spinning disk designs. I would expect the older Mini35-300 with the disk at higher rpm and the SGPro and possibly the Redrock M2 likewise, to be the most likely to cope of all. There have been operator claims of artifact-free imaging from the Brevis at f11 apertures so it may have some shutter speed latitude at much wider apertures.

On the Letus35 I have tested, whilst there was a fixed pattern artifact present in the lighting conditions I was shooting in, it did not become any worse at 1/150th sec but was quite pronounced at 1/500th sec.

I have run the CD-R sized disk on my own adaptor at approx 1500rpm with a shutter of 1/150th sec. Except for a more strobey look when de-interlaced to 25P it seemed fine otherwise. The Mini35-300 and SGPro use a smaller diameter disk so there may be an artifacted region towards disk centre.

Perhaps avoid clear uniformly bright plain backgrounds such as car bodies or lightly clouded sky in your image if you intend camera moves. In locked off shots any artifact in these areas may be less apparent.

Sticking to wider apertures with f1.8 or wider available-aperture lenses and adjusting for light with camcorder aperture and camcorder ND may help. ND gel in between the SLR lens and the groundglasss may also help avoid flare and possible groundglass artifacts which are seen to disappear with SLR lens aperture and relay or camcorder aperture both wide.

Some lenses also provoke artifacts more than others. You choices may be slightly less. I think you will find you can make it work.

Frame blending back to 30P or 24P is not likely to work as in most cases, even with disk appliances, the artifact will be largely a fixed pattern, shimmering pattern or fixed area on the image. A shimmering artifact could be reduced to something closer to a less vexing burred fixed pattern artifact by frame blending or layer stacking across three to five frames.

Last edited by Bob Hart; August 27th, 2007 at 10:27 AM. Reason: error
Bob Hart is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Special Interest Areas > Alternative Imaging Methods


 



All times are GMT -6. The time now is 03:09 AM.


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