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-   -   Out doors exposure questions (https://www.dvinfo.net/forum/alternative-imaging-methods/167579-out-doors-exposure-questions.html)

Bruce S. Yarock April 6th, 2009 02:38 PM

Out doors exposure questions
 
I have an out door shoot (South Florida) this week end and I wanted to get some feedback on how other people deal with sunny exposure.

I shoot primarily with a Canon H1 and I'll be using my Letus Extreme on this shoot.
Normaly I leave the h1's iris at around 4, and use both stops of nd filter on the camera. I had to return my Extreme to be serviced (thanks, guys) and was speaking with Hien about this issue. He suggested that I limit the nd use, and stop down the camera iris instead. he said that since the camera is focusing on the gglass, closing the iris ( like to 7-8) wouldn't be a problem. I did some tests yesterday with this method, comparing both settings and didn't see much difference. I also set the gain at -3.

Setting1-ND on full, and camera iris at around 4.

Setting 2- One stop of nd and camera iris at 7.7.
Thoughts?
Also, I forgot to try jacking up the shutter. Assuming I limit shutter to say 125, would there be any issues? Also, If I'm shooting in 24f, is there a problem raising the shutter higher than 48?
Thanks
Bruce Yarock
P.S.-Any chance of the Ultimate comming down in price? :)

Bob Hart April 6th, 2009 05:32 PM

Bruce.


This is my priority list working to remain within the practical limitations of groundglass systems.

1. Shutter 1/50th - 1/60th second.
2. Camcorder Iris - f4 - f5.6.
3. Letus Lens Iris for preferred look - up to but not smaller than f5.6.
4. Manage light levels to groundglass and camcorder with optical ND (and IR)
5. Manage light levels to camera with in-camera ND if optical ND range unavailable.
6. Polariser to manage overbright pinpoints, water etc.. Best not used for shiny vegetation. (Greens may skew).
7. Orientate camera where possible to place natural daylight source behind camera.

Bruce S. Yarock April 6th, 2009 06:45 PM

Thanks, Bob.
The most I've stopped down is 5.6.
I have polarizers for two of my lenses. I think my next purchase is goung to be a mattbox, couple of nd filters, a polarizer....that should make life a lot easier.
But for now, if it's a choice between the camera's nd filtter and closing the camera's iris, which would you choose?
I think I tried raising the shutter speed once and did get some smear.
Bruce Yarock

Bob Hart April 7th, 2009 10:03 AM

My choice would be to use all the camcorder ND to keep the camcorder iris in the sweet spot as much as I can. This should in most instances enable the use of objective lens iris settings wider than f5.6.

Increasing shutter speed to manage light levels is a very last resort, especially with an orbital or elliptoid small-excursion groundglass movement. Artifacts are more likely to become evident at higher shutter speeds.

Bruce S. Yarock April 7th, 2009 11:00 AM

Thanks, Bob. that's what I used to do and will continue. Although I can't really see any difference between the two methods in my test a couple of days ago.
I'll avoid fooling with s speed.
Bruce Yarock

Bob Hart April 7th, 2009 10:38 PM

Bruce.


What you are doing is fine. Managing the lightfall onto the groundglass to avoid flare and enhance contrast is just a little extra bonus and quite a small percentage in the overall scheme of things.

An outdoors setting where there is little natural contrast in the subject is where that little extra can help. A polariser can be just as helpful in this circumstance.


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