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-   -   My cam can't archive the Xtreme Rsolution projected in GG, & image results w/ jaggies (https://www.dvinfo.net/forum/alternative-imaging-methods/70074-my-cam-cant-archive-xtreme-rsolution-projected-gg-image-results-w-jaggies.html)

Roberto Lanczos June 22nd, 2006 11:57 PM

My cam can't archive the Xtreme Rsolution projected in GG, & image results w/ jaggies
 
It seems that my camcorder, can't archive the extreme resolution projected in the GG.

I have a Sony Digital8 camcorder, with no sharpness or edge enhacement enabled at all.

Is there any way to fix this in post?

http://www.fdivisions.com/pt_demo/pic01.jpg

Thanks in advance.

Ben Winter June 23rd, 2006 12:33 AM

You're definately experiencing a problem--but it's not from the GG. Recording the image on the focusing screen is no different than recording an image with no attachments--it's just light entering the lens. And I have a feeling many poeple will agree with me when I say that the resolution on any 35mm adapter is going to be less than without the adapter, if at all. "Extreme" resolution on any 35mm is, I'm sad to say, wishful thinking.

If you look at the hand in the lower left corner, you can see shadowing from two other positions of where the hand has been. This suggests to be that this is an interlacing problem, even if the lines are vertical and not horizontal. I don't know how to fix it other than to say deinterlace, but that's my theory.

Roberto Lanczos June 23rd, 2006 01:05 AM

Life Sucks!

Roberto Lanczos June 23rd, 2006 01:27 AM

the vertical lines don't show up when i use "blend fields" method, for 30p.

here's a small sample : http://www.fdivisions.com/pt_demo/30p_35mm.wmv

---

I wish i could go 24p, without suffering from that problem when discarding fields.

Frank Hool June 23rd, 2006 01:40 AM

I had a look to Your sample. There's nothing wrong except temperate chromatic abberation. But on the image it really seems to be lintarlace lines. Do You use camcorder left or rightside up?

Ben Winter June 23rd, 2006 06:31 AM

That footage looks okay.

Bob Hart June 23rd, 2006 08:06 AM

Roberto.

I am only guessing here but it seems to me that your camera is getting too much new information with each frame and is pixellating the image to a lower resolution to compensate.

Is your groundglass a moving groundglass. If it is, try reducing the camcorder shutter speed to 1/50th or 1/60th of a second. It is a bit hard to tell, but it seems to me from the .jpg image that there is a strong grain effect from your groundglass. If this is moving and the camcorder shutter speed is high then there's too much information for the camera's processor to cope with.

Another issue may be that you have passed from the maximum optical zoom range into digital zoom when you have zoomed in to get close to the groundglass. If you are going into digital zoom, then the image suffers such like what I see on the .jpg.

If this is what is happening, you need a close-up lens so you don't have to zoom in so much to get the groundglass image framed.

Another cause which aggravates grain effect from the groundglass is having a lens which is too close to f5.6 aperture or even tighter than f5.6. F1.8 lenses are best, wider even better, f2.8 okay if they are good, f3.5 lenses are starting to get a bit tight. f4 lenses are going to cause a problem in high contrast outdoors lighting where at least one extreme of the contrast will flicker as a grain effect or swirl or whatever. This will add to the workload of the data processor in the camera.

I am really only guessing here.

Roberto Lanczos June 23rd, 2006 12:16 PM

Quote:

Originally Posted by Bob Hart
Is your groundglass a moving groundglass?

Yes it is.

Quote:

Originally Posted by Bob Hart
try reducing the camcorder shutter speed to 1/50th or 1/60th of a second

is at 1/60th all the time.

Quote:

Originally Posted by Bob Hart
there is a strong grain effect from your groundglass

No big deal, compared with the stairstepping on the edge of the subjects.

Quote:

Originally Posted by Bob Hart
Another issue may be that you have passed from the maximum optical zoom range into digital zoom

NO.

Quote:

Originally Posted by Bob Hart
Another cause which aggravates grain effect from the groundglass is having a lens which is too close to f5.6 aperture or even tighter than f5.6. F1.8 lenses are best, wider even better, f2.8 okay if they are good, f3.5 lenses are starting to get a bit tight. f4 lenses are going to cause a problem in high contrast outdoors lighting where at least one extreme of the contrast will flicker as a grain effect or swirl or whatever. This will add to the workload of the data processor in the camera.


Here's what i have:

- Camcorder ----- Sony DCR-TRV110 ( f=3.6 - 72mm / 1:1.4 @37 )
- Lens ----------- Minolta SR-7 "50mm" ( Auto Rokkor-PF, 1:1.8, f=55mm )


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


This is my RIG:

Cam w/ Little Zoom -----> Macro(0.5x) -----> GG (1.5cm from MACRO) -----> SLR Lens

Tom Wills June 23rd, 2006 12:35 PM

That looks like bad motion blur, blown up to around 2x. I stepped frame-by-frame through the WMV, and I saw nothing that looked that bad, and nothing that isn't just plain motion blur.

I highly doubt WMV compression could have gotten rid of that kind of quality. I think your video editing software, or whatever you used to take that snapshot, was just not quite dealing with the motion blur properly. Maybe try moving the camera slower, not whipping it around.

Roberto Lanczos June 23rd, 2006 02:20 PM

Quote:

Originally Posted by Tom Wills
That looks like bad motion blur, blown up to around 2x. I stepped frame-by-frame through the WMV, and I saw nothing that looked that bad, and nothing that isn't just plain motion blur.

There's nothing wrong with the video, that's just a 30p sample with "blended fleds" mode.

The picture from the first post, is an example of how the image looks when one of the fields is discarded.

Why would i want to discard fields?.
easy. look around for all the 60i to 24p conversion methods.

Ben Winter June 23rd, 2006 02:40 PM

I think there's a flaw in your logic there somewhere. Discard half of the image, and you're just asking for the software to give you artifacts.

Tom Wills June 23rd, 2006 05:51 PM

I wish you had said that the problem is based upon converting your 60i footage to 24p. The way your post was worded, it said nothing about anything relating to 24p, it seemed to more talk about the idea of your camera not recording video properly, instead of the 24p conversion. I automatically assumed that the screenshot and the video came from the same video, and thus, that caused the miscommunication.

I think that at this point, the problem is the 24p conversion, but I guess you had figured that out already.

Bob Hart June 23rd, 2006 10:24 PM

I would now concur with Tom, Roberto and Ben in their assessment of your problem. With the combination and settings you have, there must be some other cause.

Roberto Lanczos June 24th, 2006 02:53 AM

Bob, forget about what i said about conversion... ( i posted a video sample, JUST to show how dramatic is the difference if the fields are blended )

I'm not doing any conversions at all, PERIOD.



Check my answers in post #8, and tell me what you think.

Ben Winter June 24th, 2006 01:04 PM

Quote:

Originally Posted by Roberto Lanczos
The picture from the first post, is an example of how the image looks when one of the fields is discarded.

This is what's throwing people off. If you're taking out just the odd fields, or just the even fields, your footage will have the artifacts you've described, period. That's ordinary.

So, to clear things up: In regards to the first post, showing the picture of a frame from your footage, are we looking at complete, interlaced raw footage from the camera, or just one set of fields?

Judging by the dimensions of the framegrab, you're using your camera at a 90 degree tilt. Which would explain the interlace lines going vertically and not horizontally.


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