Anyone using Alistair Chapmans MTS B4 mount on their F3?

Sparky874

Sparky874

Well-known member
Hi there. I'd be interested to know if any you have tried using the B4 2/3 inch lens mount (which allows you to use 2/3 ENG zoom lenses) on the F3. There are some compromises and it does cost approx £1,200 but it sounds on the face of it, an interesting option, esp for shooting wildlife and sporting events. :undecided
 
I'm interested in this and have corresponded with Alister for exactly the reasons above: having ENG capacity in the F3. Allowing for a min stop of F4, the DOF is the same as on other lenses yet ENG zooms are parfocal and par-exposure with an incredible range compared to most lenses in use on the F3.

What is tricky is finding a reasonable quality affordable zoom (under $10,000?) and there's the question of the supposed superior sharpness and contrast of zooms branded HD.

I'm very keen to see some footage but if it's all too new and there are few or no adapters in circulation maybe I'll get the adapter and take it to the local hire place and try out different zooms. (Adapters ....I already have Brevis and Letus adapters sitting up on the selves).
 
I already own a Canon J21 and and J9 eng lens so it would be very interesting to see how well they worked. Amongst my fellow camera operators, and indeed specialists in lens servicing companies, they really don't believe there is much difference between the SD and HD models - I have used both and haven't noticed anything. I would love to see some sample footage using the ENG lenses on the F3 but as you say its all quite new and I would be suprised to see much. I would love to be able to hire an adaptor just to test them out, but that's not possible.
 
I think it will look just as good or bad as when I used B4 on my AF101. I've used it on several occasions when the lens was an essential feature I needed to have. I know the biggest difference will be the lens used. Better Canon ax or HD lenses works fine while older lenses without IF are softer.
 
Sample footage @ 4:38, 4:50, and zoom in at 5:25 zoom out at 5:40.

http://www.youtu.be/iqJCFBZDfLQ?hd=1

Sparky funny you should mention B4 2/3" lenses, as long before 35mm video cameras were available on every street corner I remember seeing some footage by someone using one of these 2/3" lenses and shooting at 24p. For me it was reminiscent of old wildlife documentaries, but also those cheesy horror movies from the 80's.

For film purposes, I would love to get a setup like this and for the relatively low cost I think its a great idea to get one now!
 
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Doing some more research on this, it is possible to buy a B4 mount to Nikon mount for pretty cheap, then use your Nikon to Sony F3 mount (if you have one). You won't get the x1.5 magnifier from the Alister MTF adapter but you can easily do a 150% blow up in post and probably even end up with a sharper image then going through the extra glass.
 
I've always figured the biggest advantage for Alister's B4 mount is the extremely wide zoom range available (example 18-300mm) and the motorized zoom. Alister said you don't loose that much resolution and he's a straight forward guy that calls it as he sees it.

You do have significant light loss though. I think its a few stops, but then again many B4 zooms are F1.7 or F1.8 and don't ramp.

I can see where it would be worthwhile for run and gun. The same arguments are made for the Sony motorized zoom, although some people complain about the motor and toggle on the Sony zoom and the Sony costs a lot.
 
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I have the m43 version of this for my AF-100.

The real key is, unsurprisingly, the quality of the glass.

My Angenieux wide angle zoom looked excellent on it.
 
FS100 user here.

Are there more examples/tests about?

Al's shot looks really bent at the wide end, not sure if that is the ENG lens or the adapter, also the zoom example seems to have a lot of DOF, I guess he just didnt engage ND..

S
 
Duke M. said:
I've always figured the biggest advantage for Alister's B4 mount is the extremely wide zoom range available (example 18-300mm) and the motorized zoom. Alister said you don't loose that much resolution and he's a straight forward guy that calls it as he sees it.

You do have significant light loss though. I think its a few stops, but then again many B4 zooms are F1.7 or F1.8 and don't ramp.

I can see where it would be worthwhile for run and gun. The same arguments are made for the Sony motorized zoom, although some people complain about the motor and toggle on the Sony zoom and the Sony costs a lot.
Click to expand...

I think F4 speed is quite acceptable, especially for a zoom.

I also think a parfocal motorized 18-300mm zoom with constant aperture for around $1000 is a steal! (Canon J19)


morgan_moore said:
FS100 user here.

Are there more examples/tests about?

Al's shot looks really bent at the wide end, not sure if that is the ENG lens or the adapter, also the zoom example seems to have a lot of DOF, I guess he just didnt engage ND..

S
Click to expand...

Looks like this adapter is pretty new but its only main benefit would be the built in 1.5x magnifier used to cover the entire 35mm sensor. It also requires that the 2/3" lens you're using has a 2x extender built in.

My theory is to just use a 2/3" lens with 2x extender built-in and a regular lens adapter (no 1.5x optical magnifier) and then do the 1.5x magnification in post. Way cheaper and no extra glass to go through which will probably further bend the edges of the image.
 
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Editman, those are some great shots with your AF101 and J17 lens!

Just note that comparing the B4 adapter for 4/3 to the adapter for the F3 is not entirely going to produce the same results, as there is extra glass in adapter for the F3 needed to further magnify the image by a factor of 1.5. This is due to the sensor size differences:

Sensor Sizes:
Super35 25mm x 14mm
Sony F3 23.6mm x 13.3 mm
AF10x 17mm x10mm
2/3" 8.8 x 6.6mm
 
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Editman Sweden said:
I think it will look just as good or bad as when I used B4 on my AF101. I've used it on several occasions when the lens was an essential feature I needed to have. I know the biggest difference will be the lens used. Better Canon ax or HD lenses works fine while older lenses without IF are softer.
Click to expand...

what is IF and what does it do?
 
I'm looking at the following 2/3" zoom lenses, anyone have experience with any of them and any main differences?

Nikon S15 8.5-127.5MM F1.7
Canon J19 8-128MM F1.8
Fujion A16 8-120MM F1.7
 
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I'm looking at getting the MTF adapter since I already have an EF to F3 adapter. I found the J17 lens to be extremely versatile on the AF100.
 
Ok, will somebody that's smarter than me answer this: I have a Fuji wide angle zoom f1.7, 4.5-60mm. So at 2X would it be 9-120 and about f4 on the F3?
And since it's so wide, would it vignette at all at 2X?
 
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