SG Pro/Hvx and blue skies, big problem.

S

scribbles

Active member
Hi all,

The other day i started work on a short film about a bicycle trip. The entirety of the movie takes place during bright days with blue skies, with many wide shots of landscapes. Everything looked beautiful in my Panasonic BTLH80w monitor, but when i imported the footage and watched it larger, i could see the spinning ground glass clearly apparent in the blue of the sky. I was using the revision 2, with nikon mount.
I DO NOT have a matte box, nor did i use the in camera ND filters. So the hvx was stopped down to about f11 and my nikon 35mm f/2 was at about f8. I have always understood bright blue skies were a problem for any adapter but i had hoped since i wasn't stopped down to f22 or shooting with a fast shutter speed(i was at 1/48) the spinning ground glass wouldn't be seen. Well, it was.
I don't want to go out and spend huge amounts of money on a matte box and a set of ND filters if it won't fix this problem. If i keep my hvx at around 2.8, and my nikon around 5.6, would this problem be resolved? I want honest answers here, this is a huge huge problem. I'm sorry I can't test this out for myself but there is nowhere nearby where i can rent a matte box to try.
If you guys would be so kind, and if a matte box(allowing you to open up your lenses by using ND's) DOES indeed fix this problem, what matte box should i buy? I can't wait for the redrock to come out, we need to start soon.

Thankyou so much, once again.
Evan
 
Hi Evan,

Sorry to hear about your troubles.

F8 on the 35mm lens shooting bright blue skies is a problem on any adapter including spinners. Keeping the 35mm lens at F5.6 or wider will help.

A mattebox would not have solved this specific issue.
 
What was your shutter speed/angle at? when you stop down with your lens with any adapter and point it at bright light object AKA the sky, you want to keep the shutter around 1/48th and keep the lens stopped down no farther than f10, make sure with any shoot to always have fresh batteries...AA's are cheap, switch them out if it is something important.... hope you can reshoot, a matte box would help, but not totally necessary with the SG.

Jon
 
Hi guys and thanks for your quick responses.
Wayne, I hope you don't feel like i'm bashing your product, i love the SG Pro, but all adapters are still flawed and this is a big problem, people need to know about it. Again, people, this is a problem inherent with all adapters, not just the Sg, from what i've seen the Sg performs better in situations like this than do others.

You both say a matte box wouldn't have helped, this confuses me. I wouldn't be using the matte box to flag off light, i would be using it to hold my ND's. I guess a better question would be:
WOULD USING ND FILTERS, ALLOWING ME TO OPEN UP MY LENSES TO ...LETS SAY, 5.6, GET RID OF THE SPINNING LINES I SEE IN THE SKY? (the spinning ground glass)
Jon- i was shooting at 1/48th and had brand new AA's in.

Thanks
 
Wayne i appreciate your response but it still doesn't answer my question. You of all people should know. What do i have to do to get rid of these lines in the sky, is it even possible to do in camera? Will opening up my lenses solve this issue? I'm not trying to put you on the spot so i'm sorry, but please just tell me, can i or cant i completely fix this issue.
 
Wayne said 5.6 or wider would 'help', not fix it entirely. I would use my internal ND's but i've been told this does not fix the problem and only makes the spinning ground glass even more apparent.
 
Evan,

Yes I see. Using the ND filter in the Mattebox to cut incoming light, therefore allowing you to open up your 35mm lens while maintaining exposure will help with the grain issue.
 
Wayne Kinney said:
Evan,

Yes I see. Using the ND filter in the Mattebox to cut incoming light, therefore allowing you to open up your 35mm lens while maintaining exposure will help with the grain issue.
Click to expand...

So it will help, but not fix it entirely? Can you elaborate why using the in camera ND's does not work as effectively?
Thanks
 
1/48th??? sound weird, I have never had that problem with mine and I have shot sky shots at about f12 and still no grain... Yes in the case of using Nd filter on the matte box so you can open the lens up, will dissolve the grain...


Jon
 
Jon Neely said:
1/48th??? sound weird, I have never had that problem with mine and I have shot sky shots at about f12 and still no grain... Yes in the case of using Nd filter on the matte box so you can open the lens up, will dissolve the grain...


Jon
Click to expand...

what was your hvx at? was it wide open? anyway you could show me some footage pointed at a bright blue sky? sometimes its hard to notice the grain, i've watched footage of mine and thought it was fine but then three weeks later i finally see it.
my sgpro had to be sent in for repair, the motor broke as well as the spinning ground glass. everything was replaced, you don't think my motor just isn't spinning fast enough?
 
I've seen this on my HV20 with the SGpro running - but that was stopped down to f/8 or f/11. I'll do some tests and see if I can minimize it at wider apertures, it's been bugging me as well when I try to do shots that are just sky/clouds. Of course for those I could just remove the adapter I suppose...
 
I am a dvx user not an HVX user, hehehe, maybe it hiding within the lack of resolution....lol, The HVX has a lot more latitude than my DVX, and It probably more apparent with it because well thing are in better exposure range. a Mattebox will solve all your problems, with grain at least.


Jon
 
Jon Neely said:
I am a dvx user not an HVX user, hehehe, maybe it hiding within the lack of resolution....lol, The HVX has a lot more latitude than my DVX, and It probably more apparent with it because well thing are in better exposure range. a Mattebox will solve all your problems, with grain at least.


Jon
Click to expand...

your confidence that a matte box and ND's will solve my problem slightly reassures me, but only slightly. the differences between a dvx and hvx are pretty big-like you say, what may work on your camera may not work on mine. sigh...
but thanks for all your help!

any hvx users here who can tell me that the blue sky/grain problem isn't an issue at wider apertures?????
 
Enough of the panic already. What you site isn't news on the adaptor front. Even a PS will get grainy past an 8.0 or 1/125th.

With your SG stay below an 8.0 to be safe (though I've done skies at an 11.0 without grain). I'd also advise keeping your HVX in the middle of the aperture range as well (2.8-5.6). Do this you should be fine. If you still get it switch out batteries (I use rechargeables - hold charge longer). Still a problems, your motor could be out of whack. For reasons unknown this happened to me. Grain showing up under all circumstance. My motor's spindle went out of true, thus slowing it down. SG replaced it without a hitch. It happens.

If you don't want to spring for a mattebox buy some screw ons (ND 12, ND 9 and ND 6 should cover you). Make sure to get an ND 12 as ND 9 on a sunny day oftentimes isn't enough to get you to a safe stop.

Good luck.
 
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