Spinning ground glass SGBlade and HVX

M

miguelsanchez

New member
I was shooting with HVX and Blade for the first time. Very impressed with results!

Until I noticed, when I projected the footage, in some shots I can make out the ground glass spinning RR2.

I was testing with f-stops, and shutter speeds. I was liking the low shutter speeds like 1/501/70ish, and f-stops of 1.4 to 2.8 roughly, not much beyond that.

Its not visible in most of the shots, just a couple of light shots areas.

What is the general rule with spinning ground glasses? Low shutter speeds, 1/50/100 etc.. or high ones like 1/300?

Low f-stops (1.4) or high (f5.0)

What are the general rules?

Cheers!
 
the gg will be noticeable in higher speeds.
below 60 is ok
60- so-so depending on gg quality
100 above risky.

with the newer ggs of the branded adapters, high f stops at 8 even for some at 11 still ok depending also on your lens, i'm making an example of , say a 50mm f1.4.

But the rule of the thumb is limit at 5.6.

I have tested mine at f11 using a sigma 20-40 f2.8 lens. Still ok. Do some tests with your lens as to the f stops.

But for the shutter speeds, most users here say stay at or below 60. And of course anything slower.


Ted
 
Make sure your speed knob is turned to full. Sometimes its easy to knock it down and the slower disk is visable.
 
If you ever get in a pinch and need to shoot with high shutter speeds with an adapter...or just forget all of these rules. Especially if it was a big shoot and there is no way of re-shooting. our own demistate is pro at noise/artifact/ground glass removal as well as professional encoding services. He's gotten me out of a few pinches before, for example on this latest music video we really wanted to shoot a slomotion silhouette shot with a crisp high shutter speed look. And he made it look like magic.


here's an example from my last music video.


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like Dillon said you can get the footage cleaned up or you can get the same results using Neat Video plugin for premiere or after effects if your interested. Most of my footage ends up like the picture on the left. i shoot withe plenty of light and using hmc150 ,sgblade rr2, and canon 50m 1.4 and 28mm 1.8. i have the speed cranked up all the way and im either at 1\48 or 1\60.
 
I'm using an EX-1 and with RR2 I don't see the "windshield wiper" effect when I am at 2.8 though I don't like to close down much more - and can see it at f4.

It may vary with the camera you're using in the first place. Even sometimes the lenses themselves can affect whether you see grain.

When I had a Brevis on some of their screens I could use my Nikon 1.4 primes at f2.8 with no problem but got lots of grain with my zoom at 2.8 even though the exposures were the same. The size of the exit lens on the zoom was smaller though. That's not intended as a comment on the Brevis but rather on the oddness of what can cause static grain.
 
Lenilenapi said:
I'm using an EX-1 and with RR2 I don't see the "windshield wiper" effect when I am at 2.8 though I don't like to close down much more - and can see it at f4.

It may vary with the camera you're using in the first place. Even sometimes the lenses themselves can affect whether you see grain.

When I had a Brevis on some of their screens I could use my Nikon 1.4 primes at f2.8 with no problem but got lots of grain with my zoom at 2.8 even though the exposures were the same. The size of the exit lens on the zoom was smaller though. That's not intended as a comment on the Brevis but rather on the oddness of what can cause static grain.
Click to expand...


Well as i said i usually like to shoot high shutter speeds especially for slow motion. And that is the only time when this becomes most noticeable.
 
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