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My goal with this test was to focus on whether c-mount zoom lenses in general are worth using with the GH1 for film. There have been a few posts on the net by still photographers but not many tests from filmmakers. Most results have been so so though.This is mainly because c-mount zoom lenses generally have a small image circle and do not fill the image sensor of the GH1. So you get the Peep Hole or looking though the lens of a barrel effect.

So here's the bad with c-mount zoom lenses:

Image circle smaller than sensor
Vignetting and smearing at the edges of the frame
Resolution loss
Wide focal lengths have very small image circles, nothing usable until 25mm- 35mm and higher focal lengths
Depending on the lens, you may need to machine it to fit the c-mount adapter in order to achieve infinity focus

Alright that's a lot of not so great reasons especially for those like myself who are filmmakers unless you have a stylistic piece you want that image circle to fill that entire sensor through out the zoom range.

So why waste the time.
Because I'm stubborn and I want to make it work anyway.
So I thought I'd test it out.

The first lens that I'll be testing is the Angenieux Type L2/L3 1:2.2/17-68 c-mount zoom lens. It is not perfect by any means and has many of the problems that I pointed out that are the downsides with c-mount zooms but over all I was pleasantly surprised to see some really good results. The clip that is posted here are just straight up mundane doc style footage. Nothing fancy. Just cut and dry. So please excuse some of the shakiness and random footage or commentary by me at the end. I didn't have my tripod and am still testing out my own variation of a Gorillapod and a Noga Arm called a Gorilla Noga.

The footage was shot in my stomping grounds Chinatown North and Chinatown proper in Philadelphia. I used no ND filters just the lens and shot only 1080/24p with a shutter of 50 and 720/30p with a shutter of 50 as well. All clips had pull down removed using compressor.

Obviously,when using the GH1 digital 2x setting, you are getting an image that is cropped with resolution loss but the results are better than expected. I think scaling up the image and cropping out the vignetting and the "Peep Hole Effect" in Final Cut Pro seems to help with a better image but I have to do a few more tests to be sure. I think despite the image resolution loss it would be very usable for HD presentations on your HD Flatscreen tv or local indy community film screening. For those who are still putting out SD material which we all still do, the footage will be very usable.

Here are a few pluses for using zoom lenses on a GH1:

You can find c-mount zoom lenses that are faster, many can find at f/2.2, f/1.9 even f/1.2!!
Many c-mount zoom lenses are smaller and lighter than the stock lens especially tv lenses
You can focus much more easily with a small c-mount zoom than the stock lens
Some are still super cheap!! You can find many c-mount zoom security lenses or tv lenses for $50-$100
Despite the resolution loss you can still use the digital 2x and get some nice results or shoot wide with the peep hole circle showing and enlarge and crop in post and get better results.
So you lose your wide shots with the digital 2x zoom, just step back farther when you are shooting!

What do you get when you cross a Joby Gorillapod SLR- Zoom and a Noga HOLDIT 3-Joint Locking Articulated Arm?
A GORILLA NOGA!!

It's a mini tripod!! It's a DV stabilizer!! It's a mini steadicam!!

Just before the GH1 came out there were lots of folks exploring ways to stabilize the GH1. Because of it's small size, many folks this summer looked at the Joby Gorillapod as a possible GH1 stabilizer.

One of the first pics that I found putting together this idea with the GH1 and the Joby Gorillapod was from Flickr user retroleum who posted this great picture of the GH1 and the Gorillapod as stabilizer.

Of course many GH1 users continue to tinker with their gear to create modified rigs with bastardized parts from our old 35mm adapter rigs that are sitting and collecting dust. Inspired by retroleum and folks at DVXUser forum, I started to tinker too. I bought a Joby Gorillapod SLR-Zoom (you can find them for $30-45 bucks) and I felt it was useful but it didn't have the flexibility of use that I needed it for my work. I wanted to create a simple rig that could be put in a small camera bag and used for the documentary that I am working on about the Jook Songs Asian American performing group at Yale University.

It's the 10 year anniversary of Jook Songs and we are putting together a little doc to commemorate the groups existence. What I'm currently doing is sending a GH1 in a small camera bag all around the country to members of Jook Songs past and present for a portion of our documentary called "Video Check-Ins". Each member will get the GH1 package and film a day in their life as well as give reflections on the impact of the group on their lives today.

I wanted to put everything they needed in a small camera bag including a tripod, stabilizer, and steadicam. Ha! Of Course we all would to put all our gear in one small bag. At least I tried…

So I rummaged through my gear and found a heavy duty Noga arm that I wasn't using:

Then I rummaged some more and found a 3/8-16 and 1/4-20 Universal Converter kit that I purchased from filmtools.com:

Then I attached the pieces together to a Joby Gorillapod SLR-Zoom Tripod:

I put it all together and viola! The GORILLA NOGA!

This little guy folds down and pops into my GH1 camera bag. It's super light weight, flexible, and gives you the ability to have a small tripod, a camera stabilizer and a mini steadicam, all in one, all fitting in a little bag.

In fact, all the footage shot for my c-mount zoom Angenieux tests were used with the little GORILLA NOGA mainly as a mini tripod and GH1 stabilizer. Some footage was a little shaky but that's at the higher focal ranges where having a tripod should be the norm. You can view a little bit of the Angenieux footage with the GORILLA NOGA abilities here on this blog.
One of the great things about using the GORILLA NOGA with the GH1 and Angenieux Type L2/L3 zoom lens is since the lens is so small it does not create a top heavy feel to the GH1 allowing the use of the GORILLA NOGA's flexibility to create a counterweight to allow for a pretty successful steadicam feel.

Here is a tutorial that I put together for the Jook Songs group who will be using the GORILLA NOGA and the GH1. You can just skip through my simplistic explanations on GH1 use. I apologize in advance for my simplistic tutorial on the GH1's use but I just needed to convey the use of the GH1 to users who may be technically challenged.

Browsing Category Gorilla Noga

GH1 with C-mount Zoom Test

The GORILLA NOGA on GH1