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G1, B+W, Cine Lenses, & 1 Color Pic

wjlapier

Member
A nice day today in SE Washington, and I had to get out and try these little lenses. All shots are from c mounts. Kern Switar 25/1.4, Wollensak 1"/1.9 and 1"/2.5, and Som 1"/1.9. Most are shot at f8 or 11 ( I was also shooting my M3 with Tmax and thought I would compare once I developed the film ). I like the Dynamic B+W mode in the G1.

Wollensak 1"/2.5 between f/8-11
 
Very nice pictures, Bill. And none of them shows any vignetting. Do you always show the full format w/o any crop or vignetting correction? I am particularly interested in the Som Berthiot, I saw a 20mm I might be interested in.
 

wjlapier

Member
Very nice pictures, Bill. And none of them shows any vignetting. Do you always show the full format w/o any crop or vignetting correction? I am particularly interested in the Som Berthiot, I saw a 20mm I might be interested in.
I need to start keeping notes--

The Som, and the two Wollensaks don't vignette--but I think the Kern does vignette stopped down. These were slightly cropped because I wanted to see if I could rid the photos of the dreaded smear. It's there, but not as bad with the Som.

As for wide open shots--here is one close to wide open with the Som at I think f/2.5 or so.
 

wjlapier

Member
I plan on doing more controlled testing with notes sometime soon. I'd like to have some sort of source to refer to in regard to the C-mount lenses. Robert has suggested keeping a database of lenses with various parameters, and after seeing the smear ( not sure of the term ) at the edges, I would really like to know more of what these lenses can do. I was pleasantly surprised that the Wollensaks and Som didn't vignette, even stopped down.

I know I could have taken all but the wide open shot with the kit lens, but to me it's about having fun with the camera, and the lenses are so tiny compared to anything I've ever seen,, old and super heavy for their size, I just had to try them stopped down :) But I'm aware that alot of folks are interested in how these lenses perform stopped down because, for now, we don't have any fast primes specifically made for the G1.
 

monza

Active member
Very nice photos Bill. :)

I've been contemplating if this cine lens edge smearing is the same thing as with some of the M-mount lenses. The smearing on M mounts is clearly not related to sensor coverage, rather, due to lens design. Perhaps some of the cine lenses are simply straining to cover the entire sensor as the 22mm image circle of µ4/3 is much bigger than the 12.8mm of 16mm cine cameras (or the 14.5mm of super 16.) The fact that any of these lenses cover the sensor at all is a bonus. :)
 

Jonas

Active member
Robert has suggested keeping a database of lenses with various parameters, and after seeing the smear ( not sure of the term ) at the edges, I would really like to know more of what these lenses can do. (...)
That is an interesting idea and I'll be happy to contribute with the little I know. What parameters has been discussed? Do you know where Robert's post is, or where this database is discussed?
 

monza

Active member
Hi Jonas, Bill and I have been discussing amongst ourselves. :) So there isn't a post, or a database for that matter. The parameters we have listed include:

Manufacturer
Model number (if any)
Mount (c-mount, Arri, etc.)
Focal Length
Aperture
Rear lens diameter
Sensor coverage (16:9, 4:3)
Machining required?
Length
Weight
Minimum aperture

What are you thoughts? Anything that should be added or deleted on this list?

It would be nice to have photos of the actual lenses as well.
 

TRSmith

Subscriber Member
Just a casual observer here since I don't own the G1. But I must say that I really LIKE the "smear". In fact, one of the attractive things (to me) about the ability of the G1 is the chance that you might be able to mount some lens you find at a flea market on the thing and it will yield some odd results that can't really be duplicated in post. Sort of special effects lens.

While it's mildly interesting that you can mount a $150 lens on the G1 and achieve modest results that hold up as "not bad considering the price", I think there's potential here to find ones that yield a unique "look."

Just a thought and thanks for sharing your experiments!
 

wjlapier

Member
Very nice photos Bill. :)

I've been contemplating if this cine lens edge smearing is the same thing as with some of the M-mount lenses. The smearing on M mounts is clearly not related to sensor coverage, rather, due to lens design. Perhaps some of the cine lenses are simply straining to cover the entire sensor as the 22mm image circle of µ4/3 is much bigger than the 12.8mm of 16mm cine cameras (or the 14.5mm of super 16.) The fact that any of these lenses cover the sensor at all is a bonus. :)

The whole smearing issue isn't clear to me. I see something in the edges of the pictures, so i thought it was the smearing, or what ever it is, that was duscussed here last week.

BTW, sorry Robert for bringing up the database idea, maybe prematurely. We should start a thread and discuss the parameters, and shooting technique required so that we can, as much as possible, maintain some sort of constant--someone needs to be looking over my shoulders to make sure I'm taking notes :rolleyes:

Here is an image from the Wollensak 1"/1.9 at about f8 or 11 using 16:9 ratio.
 

monza

Active member
It's definitely smearing, but maybe it doesn't really matter what the reason is behind it. :)

Regarding a database discussion, I'm all for starting it in this thread. There are lots of people experimenting, and bits and pieces of information on various threads and forums. It would be valuable to have all this information in one place. I've already started a Google Docs spreadsheet, which can easily be publicly viewed, once it has some real data. :)
 

Jonas

Active member
Manufacturer
Model number (if any)
Mount (c-mount, Arri, etc.)
Focal Length
Aperture
Rear lens diameter
Sensor coverage (16:9, 4:3)
Machining required?
Length
Weight
Minimum aperture
Hi,

That list covers a lot of the basics.

Filter threads?
Inbuilt hood?

The only C-mount lens I have tried is the Pentax 25/1.4. That's a CCTV lens and thus not really the same thing as a cine lens. I was a little surprised when I got it finding that the both the focusing ring and the aperture ring are well damped. Other findings are that there are no click stops (the aperture ring) which I guess some may care about while other user will be happy not to have. Locking pins (not of any interest to me, but you never know)?

I think links should be included, links to members reviews and links to sample images.

Taking it a step further I would like to encourage people to write their personal reviews of lenses they try, use or love. The mentioned Pentax for example has a focus plane that is anything but plane, it has 8, not rounded, aperture blades, the bokeh is nice and coma is pronounced (and more). It takes 27mm filter (not 40.5 as B&H says). Such things could easily be commented on if there was an easy to fill in form for "reviews". That way one doesn't have to be a literate and native English spoken person to share knowledge.

Right now I am using a Canon FD24/2 for my normal lens. I have a Hexanon UC 28/1.8 on its way. Are such lenses of interest as well?

Then again, I tend to overdo things.
 

monza

Active member
Jonas,

Filter size and hood info are good to add. Also, click stops (this will be of value for GH1 owners...silent adjustment of aperture while filming.)

I also added a 'type' field in the spreadsheet to indicate CCTV or cine.

This could be all-inclusive and cover every conceivable lens and lens mount, although the cine lenses are somewhat of a special case due to sensor coverage questions and possible machining which generally aren't the case with adapted 35mm lenses.
 

Jonas

Active member
This could be all-inclusive and cover every conceivable lens and lens mount, although the cine lenses are somewhat of a special case due to sensor coverage questions and possible machining which generally aren't the case with adapted 35mm lenses.
Hi

Covering everything isn't bad, is it... ;)

OK, let's leave the 35mm lenses aside for now. But having space for links to possible reviews and sample images can't hurt, can it? Some job of course....
 
Model number (if any)
Mount (c-mount, Arri, etc.)
Focal Length
Aperture
Rear lens diameter
Sensor coverage (16:9, 4:3)
Machining required?
Length
Weight
Minimum aperture

What are you thoughts? Anything that should be added or deleted on this list?

It would be nice to have photos of the actual lenses as well.
Completely agree. May I add an observation about measurements. We Europeans use metric, US use imperial. I think it is quite important to standardize on one system (of course metric !!!) or have both, or confusion and misunderstandings will arise. To me, for instance 3/8" is a riddle, I must first look for a conversion software to understand what it means in mm. Sorry to speak for my own.
 
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