35mm adapter for b4 mount under $5000

35mm adapter for b4 mount under $5000

  • Yes!!!, Are you kidding!?

    Votes: 62 89.9%

  • No Way!, I would rather buy the real pro35 with the extra $28k in my pocket

    Votes: 7 10.1%
  • Total voters
    69
Andrew McMillan said:
http://zacuto.zenfolio.com/p467919464/hea40600#hea40600

remember this at NAB 08. Never really showed up. It was supposed to be $4,500 for just the relay. plus 4,500 for the letus ultimate or 1,000 for the extreme.

I think that pricing is a bit ridiculous. Wasn't the original question under 4k for the whole adapter! Come on letus I thought you were an indie friend:crybaby:
Click to expand...

So these would work with SLR lenses right? Like Nikkor?
 
There have been technical delays in the development of the Letus B4 relay. It won't be out until the end of the year at the earliest.

Peter
 
alright, at least some good news about the relay.. Dennis, will your b4 relay work with other adapters? letus? sg ?
 
I just bought a set of canon EJ prime lenses second hand in perfect condition.
They perform almost exactly as my set of nikons did with a letus adapter on the hvx200....
It seems to me that this is a far better solution than an adaptor/nikon/relay set up...
The price is not much different either
 
spencerdare said:
I just bought a set of canon EJ prime lenses second hand in perfect condition.
They perform almost exactly as my set of nikons did with a letus adapter on the hvx200....
It seems to me that this is a far better solution than an adaptor/nikon/relay set up...
The price is not much different either
Click to expand...

I am unclear how a 2/3" B4 mount lens could have the same field of view and depth of field of a 35mm SLR lens and 35mm DOF adapter?
 
Beautiful shots. What camera were these shot with? It looks like 2/3" at f1.4 but it looks very soft for an HD camera?
 
I agree that the shots have a very shallow DOF for a 24mm 2/3" B4 lens(which is similar to a 50mm 35mm lens). I'm sure they were shot wide open at F1.5. They would certainly be a faster alternative to any 35mm DOF adapter.

The Canon EJ primes were designed for 4:3 SD cameras originally. While they look okay with an HPX500, the real test would be to use them on an HPX3000 or F900R or some other 1080p full raster camera, as the 500 doesn't have the resolving capability due to sensor limitations. The 6mm could vignette due to its 4:3 mask. These are 15 year old lenses not designed for HD cameras, but if they could be bought for $10K or under, could be worth considering.

Regarding a Letus Ultimate, you won't see grain under most normal shooting conditions even if stopped down to F22 as long as the GG is at the highest speed. The soon to be available Letus B4 Relay Lens, rated at F1.8, will cost $3500, a $1000 reduction in the anticipated price point.
 
The 24mm is a telephoto lens because 24 x 2.5 = 60mm at S35 FoV and 35 x 2.5 = 87.5mm at S35 FoV

So the real thing is to try the 10mm and the 15mm...

The trick to use telephoto lenses is good and it is known to all DoP's that used to work with 16mm...

But when the story is unfolding the directors wants the wide angle lenses more commonly like the 10mm and the 15mm and some times the 24mm so then there is a problem... also when you don't have the luxury to shoot from 10m away there is a problem again...
 
Assume you put that 10mm f1.4 on the 2/3". You get the equivalent of super35 using 25mm and f3.5 DOF. Not that bad. A Red One with its zoom or Nikkor lenses will give you f2.8 at that focal length.
 
The difference shouldn't be that large. Don't put T stops in the way (the t1.5 is f1.4 and equivalent to f3.5 not f4. That calculator does not even have f3.5 vs f2.8.

At 1.7m and your wide angle lens:

Super35 25mm f2.8, 50 cm DOF
2/3" 10mm f1.4 61cm DOF

At 5m and a telephoto lens:

Super35 250mm f2.8, 4.08cm DOF
2/3" 100mm f1.4 5.04 cm DOF

Not that important.
 
The Panavision calculator is using a different COC which is plain nonsense. COC is 0.001" vs 0.009mm. That produces the errors. The projection will be at equal resolution and equal size, so the COC should be identical.

Btw, a different COC only changes DOF and not the look of out of focus material which is only infuenced by angle of view and absolute aperture size. If you take HD and reduce resolution to SD or a low resolution net version, COC will change, the DOF in calculators will change with that, but the DOF look will be identical.

Somebody should write an article on this topic. There s confusion on magification and zeiss factor vs resolution in modern digital media and COC.
 
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OK I will do a real world comparison with both lens to see the real life difference...

In that way we will cross check the theory with the reality...

I will need few days Otis...
 
The problem is we have checked in reality. We know what the difference in DOF of 2/3" and super 35mm is.

I was wrong about COC scaling, it's an old and acceptable film practice to scale COC and I assume it applies if the results have the same final output size and resolution viewed from the same distance (projection).

I just did the following graph. This uses the accurate (non simplified) DOF equations, everything is in mm, uses a COC of 0.009mm like panavision for 2/3" and 0.0225 for super35 (with proper scaling, Panavision use 0.001"=0.0254mm). It ends at 1700mm (x axis) and DOF limits are on y axis. The results agree with the DOF master online calculator but I'm not sure the graph agrees with the Panavision calculator.
 

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So anyone know of any inside info on when these B4 35mm adapters will come through? I seriously need one within the next few months. The Pro35 is way too expensive and renting is not an option.
 
STORMDAVE said:
So anyone know of any inside info on when these B4 35mm adapters will come through? I seriously need one within the next few months.
Click to expand...

Contact Letus Corp. or Letus Direct or Zacuto in the US, Mitcorp in Europe. I think
you will be happy you did, their two B4 relay lenses will be available shortly.
 
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