2/3" B4-mount lenses on AF100, complete ENG kit concept

these contraptions to make the af100 into an eng camera are getting more and more expensive/complex. i was doing the same thing with mine, spending so much money on it so that it would be shoulder mountable, and record onto p2 cards, but it was getting so big and heavy... at the end i decided to sell that rig, camera, lenses and all. then i went and bought a hpx3100. it was almost the price of my af100 rig. and that is a true eng camera.

but then i went back and bought another af100. all my friends thought i was crazy, because i just sold one and then i turned around and bought another one, but i like the little thing. the only thing, this time i am not doing any crazy stuff to it. like that old saying, "keep it simple, stupid".
 
Like Matt, I was pretty excited about the concept of using my nice wide 2/3" HD zoom on the AF...until I saw the price of the kit. Yikes.
And the thought of hanging my l-o-n-g and heavy wide zoom on that already-overburdened little camera seems silly, not to mention an invitation for a three-part mechanical disaster.
I guess I'm with Lenny here...I'm going to keep it simple and use the $7 grand for some nice glass.

Kudos to Abel for the clever (if pricey) solution, but it seems to open up a whole other can of worms that I guess I'd rather not deal with.
 
Mitch Gross said:
And suffer dramatically lower quality images. An internal doubler is designed to magnify the image for the 11mm image circle of the 2/3" video format. It may or may not mechanically allow for the projection coverage out to 22mm. And the optical design is for that inner area. Once outside of that "sweet spot" the falloff in resolution, contrast, chromatic abberation, etc. can be dramatic. The internal doubler does not correct for 3-chip optical design (that's what B4 is) to a single chip sensor like the AF100, where all three color channels need to land on the same depth plane. And lastly the physical mount on the AF100 is rather lightweight, so if you took some little adapters to get your 2/3" zoom on the camera and then tried to puick it up using the lens' servo handgrip, you could very well rip that mount right off the camera.

There's a big, big difference between them.
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I see your point, but there are people here who have already experimented with B4-mounted SD lenses that have a 2X extender. Sure, they may not be as sharp as the solution Abel is offering combined with an HD lens, but they offer an inexpensive way to experiment with a lens they may already own.
 
Mac said:
That's true of the Abel's device as well.. In fact, it freaked me out when I saw him support the rig with the lens.
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The beauty of the Hot Rod Tuner kit is that the PL mount adapter is supported directly to the 15mm rods, which are then in turn directly mounted to the support base. So everything supports from the base and there is no pressure on the camera's lens mount. It is very, very solid.
 
mcgeedigital said:
Which is what a lot of you are missing . I have a killer Angenieux HD wide angle I would love to put on my AF-100.

If this solution enables servo zoom, start/stop, and covers the AF100's image sensor, I would be all over it.

it's funny, people complain about there not being a servo zoom for the af-100, and then Abel comes out with a solution and everyone bitches at the price.

You can't win.
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Thanks Matt, that was my initial intent. The fact is that one cannot get a high magnification zoom for M4/3". They just don't exist. The biggest magnification fo 35mm cine is 12x, which is the monsterous Optimo 24-290. ENG lenses are regularly available in 17x, 20x or more, which is great for the functionality of the AF100.

If this is not useful to you then so be it. But from the responses I've gotten in the last few days, it is very useful to many others.
 
This is appealing to me since I have a lens, and the footage looks great. In fact, to my eye, better than most of the other AF100 footage I've seen.

So Mitch, the downside is a 2 stop loss, correct? But with the (supposed, I don't have an Af yet) cleanness of the ISO, that shouldn't be much of a problem, right?
 
I agree, the footage has quite a lot of detail. Mitch, do you have a direct comparison as far as f-stops used with the AF-100 compared to the f-stops used with a 2/3" eng camera like an HPX-500? Just wondered if with the AF-100's ISO it is possible to get even or maybe better performance from a traditional setup.

Thanks
 
As you can see in the video, it was pouring rain so we were just out there a few minutes. I didn't shoot a 1-to-1 comparison test with another camera or a difference lens option. The AF100 has an interesting aspect to its gain circuitry. There doesn't seem to be any difference in noise no matter where one sets the gain. That is to say, it always has a bit of noise. So while I believe the sensitivity at 0db is around 400 or so (that's from memory and it's 3am, don't absolutely quote me), one can bump up the gain +12db to get back the two stops lost to the HDx2 adapter with no increase in noise.

The HDx2 does a lot more than simply magnify the image. It also is specifically designed to take the three chip prism design of the 2/3" B4 mount lens and correct it to the single chip sensor of the AF100. It is also a highly telecentric design, which greatly helps reduce issues on the edges of frame, such as chromatic abberation, resolution dropoff and brightness dropoff.

It takes a lot make a 3-chip prism and I've seem inaccuracies in alignment registration of the three colors on plenty of cameras. The flagship 3-chip camera of the Sony fleet is the F23, and after the first of these cameras were introduced they were famously recalled so that Sony could install a brand new design of improved prism block. Good for Sony but it does illustrate that there can be imperfections on lesser cameras. All this to say that I generally find that these B4 mount lenses have never looked as good as they do when used with these rigs.

As far as the sensitivity comparison to another camera, the HDx2 eats two stops of light because it is expanding the image twice as tall and twice as wide. If another camera has the same native senstivity as the AF100 then the use of this rig wil show a two stop difference in overall brightness. But given the comparison you requested (to the HPX500), the AF100 has better dynamic range, higher resolution, and shows much less noise when gain is applied. Plus it has native 1080/60p. So I think you might find this a step up.
 
Here is some test to show why an ENG lens on the AF100 is a big win, at least for me. It's very zoom happy footage, but that is what I wanted to check out in particular. Having purchased the 14-140 as my first lens, it was pure joy to see the ENG B4 lens option working. I wont have to completely abandon this style of shooting... Ciecio7 adapter $300. Canon 9x15 ebay $450. iso 1000.

http://vimeo.com/20729392
 
a7sharp9 said:
Here is some test to show why an ENG lens on the AF100 is a big win, at least for me. It's very zoom happy footage, but that is what I wanted to check out in particular. Having purchased the 14-140 as my first lens, it was pure joy to see the ENG B4 lens option working. I wont have to completely abandon this style of shooting... Ciecio7 adapter $300. Canon 9x15 ebay $450. iso 1000.

http://vimeo.com/20729392
Click to expand...


This looks like a cool solution.. Tell me more about it. I assume you ended up with a pretty long lens using this... Correct?

Jay
www.infotechacademy.net
 
Thanks for your 3 a.m. reply Mitch! Quite an interesting setup option. If you ever have the chance of taking a little footage of the same scene with the AF-100/B4 and a 2/3" camera to note the f-stops it would be appreciated.


I would like to ask, if the AF-100 at $5,000 is giving a great image what would a 2/3" chip version of the AF-100 look like? Could a little shoulder mount version be made for under $10,000 that would have a 2/3" prism adapter built in?

Obviously this would compete with the expensive cameras but it would be a nice tool.
 
Jay A. Kelley said:
This looks like a cool solution.. Tell me more about it. I assume you ended up with a pretty long lens using this... Correct?

Jay
www.infotechacademy.net
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The lens is 9-143. With the 2x extender it's essentially 18-246... Ths lens may end up being my most utilized lens. I thought I'd have to split time between the af100 and hpx170 for a few of my corporate clients. I think that dilemma has been solved with this solution. Super smooth zoom. No noise. Great image IMO. Well made adapter... I may add the power option from AbelCine for event stuff if I want to go that far with this setup.

Jonathan
 
Mitch: Here's a slightly off-topic question. I've read in other threads that there is a noticeable lag with the HDMI signal. Using the Cineroid (I got one from Abels CA, but not an AF100 yet) is the lag a problem?
 
a7sharp9 said:
Here is some test to show why an ENG lens on the AF100 is a big win, at least for me. It's very zoom happy footage, but that is what I wanted to check out in particular. Having purchased the 14-140 as my first lens, it was pure joy to see the ENG B4 lens option working. I wont have to completely abandon this style of shooting... Ciecio7 adapter $300. Canon 9x15 ebay $450. iso 1000.

http://vimeo.com/20729392
Click to expand...

Do you have any pics of your set up?
 
Denwa said:
I would also like to see some pics of your setup. What model lens did you use?
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+1 a7sharp9, I am really interested in your rig. I can get an SD B4 ENG lens easy enough, and I would love to have it for some run and gun stuff that is going to web that I use the HPX for as primes are not practical. Although an $8K solution is not practical for me, if I can get something going under a grand with out the glass, I am on that.
 
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