HPX170 Crop factor

EDV

EDV

Well-known member
Can somebody explain to me the crop factor on this camera?

The reason I ask is I'd like to use the Zeiss 18mm f/3.5 Distagon T* ZE Lens, and I'd like to know how the crop factor will affect the field of view on this wide angle.
I am using a 35mm adapter ( SGBlade ) so that probably makes the crop factor even worse?

Lets look at an image taken with a full frame camera with this particular lens.

2ymgdbc.jpg


How much of this image will the Crop factor of the HPX + 35mm adaptor combo let me see? Only the center portion? Can this be "fixed" by simply moving the camera further away from the subject?

Thanks in advance
 
The camera has nothing to do with it, the 35mm adapter will be what determines how much of the lens you will be able to see. Some of the adapters let you see the full size of the frame, some don't. You'd have to specify what adapter you're talking about using.
 
SGBlade RR2 Barry. I did a side by side test with a 80 -200mm zoom lens with disappointing results...

http://vzaar.com/videos/1060505

The full zoom range did not give me any extra range over the fixed lens. I am now thinking of selling this lens.
 
Well, yeah. The HPX170 by itself has a crop factor of 7.2, and a 13x lens range, which means it has a 35mm equivalent range of 28mm - 364mm. So using an 80-200 would nowhere near approach the telephoto the HPX could get by itself.

But the 80-200 on the RR will give much shallower DOF.
 
For me, the ability to use a range of lenses ( PL mounts are also available for the SGBlade ) rather than a fixed lens was the main reason.
Sure, there is a loss of sharpness, but if you choose your primes wisely you won't notice it. You may even notice a sharper image depending on what prime lens you're using. Anyway, the whole point of using a wide angle lens with the SGBlade was not to get shallower DOF, but to get nicer wide -angle shots: landscape timelapses, group shots, context shots... something the HPX170 fixed lens does poorly by itself.
 
Barry_Green said:
The HPX170 by itself has a crop factor of 7.2, and a 13x lens range
Click to expand...

So considering that...

How much of this image will the Crop factor of the HPX + 35mm adaptor ( SGBlade ) let me see?
Feel free to illustrate your point. :)

2wn6az7.jpg
 
When the adapter is attached, camera crop factor is not relevant. You zoom the camera to whatever level allows you to capture the entire image projected on the spinning ground glass. That image should be close to what you have in your other photo. But depends on the specific adapter and how much you need to zoom in the hpx to eliminate the black borders around the projected image.
 
Yes, the answer was similar but ended with a question.

Barry_Green said:
The camera has nothing to do with it, the 35mm adapter will be what determines how much of the lens you will be able to see. Some of the adapters let you see the full size of the frame, some don't. You'd have to specify what adapter you're talking about using.
Click to expand...

But I guess at this point the answer is " it varies ". Good enough I guess. The zoom lens I refered to earlier did not go well with the SGBlade + HPX, but a Nikon AF-S 105mm f/2.8 Macro lens worked wonderfully.
[h=2][/h]
 
The answer is -- it all depends on the adapter. Some will allow "full frame". Some will allow "S35". Some won't. If you use an adapter that allows "full frame", then you will get exactly the same field of view, DOF, and perspective as shown in the original picture. If you use an adapter that doesn't allow that, you won't. Only way to know is to test...
 
Understand this -- it has NOTHING to do with the HPX170. The lens will project an image onto the adapter. The HPX170 just films that projected image. So whatever image the adapter is capable of, the HPX170 will show it exactly the same way as an HMC150 would, exactly the same way as an HVX200 would, exactly the same way as an HPX250 would, exactly the same way as an HPX500 would, etc. The field of view effect you're looking for takes place between the stills-camera lens and the adapter, regardless of whether there's a camera attached or not. Heck, you could take the adapter off the camera and just look through it, and you'll see what the field of view would be, just look at the screen with a lens attached...
 
Thanks for that Barry. Just got a bit confused reading some other crop factor thread where someone was upgrading from the HVX200 + Adapter to the AF100. One of the responses said that "The angle of view on the AF100 should be about 3x wider than the HVX" while someone else said on the AF100 "all your lenses now produce a narrower FOV". So what is it? Narrower? or Wider?
And how about explaining it visually?

w9egip.jpg


The circle is the entire image the lens projects onto the sensor plane. The rectangles represent two different sensor sizes, and show the amount of image they capture. The larger RED rectangle represents a full-frame (5DII) DSLR, while the BLUE rectangle represents the crop-frame (7D, T2i, AF100? ) How much narrower or wider would the HVX / HPX170 be?
 
The thing that's confusing is they said "HVX200 ** with adapter **". So it's not the HVX200's field of view that's being discussed there, it's the field of view of the 35mm adapter.

An HPX170 without any sort of adapter is going to have a "crop factor" of 7.2. Meaning, to get the same field of view as a full-frame 35mm stills camera using a 100mm lens, you'd have to use about a 14mm zoom setting on the HPX170.

The HPX170 has the equivalent of a 28mm - 364mm lens on a 35mm stills camera.
 
Im pretty sure with my redock encore, I get the same field of view as if it were a full frame cam, The ground glass is big enough to project the entire frame, So in essence, my xha1/redrock m2encore, is the same as shooting with a 5d, I think?
 
maranfilms said:
Im pretty sure with my redock encore, I get the same field of view as if it were a full frame cam, The ground glass is big enough to project the entire frame, So in essence, my xha1/redrock m2encore, is the same as shooting with a 5d, I think?
Click to expand...
In terms of field of view, yes.
 
SGBlade seems to have been discontinued, but both the Letus Ultimate and the Redrock M3 are still being sold. I know a couple of very talented cameramen who still use them as well as some film schools, but hardly any rental houses offer them these days.
 
To think that not so long ago, even Film and TV productions had 35mm adapters as a viable alternative...

2w6vuw7.jpg
 
I miss the good ol' days of the big badass cams. Everything is so tiny these days, especially at the indy level...

68a79f.jpg
 
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