XH footy from the Brevis35

Dennis Wood

Dennis Wood

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Here's a clip featuring my favourite subject :-) I've included audio straight from the XH-A1 onboard mic which is set at the camera defaults. The mic is about 2 inches above and 1 inch back from the adapter and the adapter of course is running.

104 MB full frame HD, 10K Kbps wmv
52 MB half frame HD, 5K Kbps wmv

The 50mm Canon FD f1.4 lens is set at f2.8. The camera settings varied from f2.4 to f8. The Brevis is using our prototype CINEFUSE 3 imaging element (diffuser).

Did I mention I really, really like this cam? It was using preset 8 (Cine V) which I've tweaked a bit.

EDIT: If you were wondering about the chromatic aberration/blue meanies to the left of the gentleman's head, here's a clip of the bare XH-A1, at f 2.4 and f 4.8 . The blue halo is from the A1 at full open!! Here's the clip.
 
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Pretty nice. I will say that the CA was very noticable to me. There was a blue "halo" around the subject. Even my wife (who doesn't know anything about video) looked at the clip over my shoulder while I was checking it out and asked "is that a special effect or something?" She was referring the blue "halo" CA effect.

It'd be interesting to see footage with and without the Brevis.
 
I'm not too concerned on the CA, mostly because the proto diffuser is a bit of a hack job right now. If I could post pics of it, it would be immediately obvious. To be honest, I'm surprised there's not a full rainbow complete with leprechaun and pot o' gold at the edges :-) Fortunately, the real McCoys are on their way. I am very curious though as to how the A1 does by itself.

I'll have lots more footage posted up shortly. Getting outside is a bit of an issue being that it's -22 C out there right now.
 
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Thanks for sharing, Guskers! Call me crazy, though... it seems like the A1 glass does this all on it's own!

I'd have to see more extreme examples. But, at telephoto and with the wide-angle and without, I see footage like this popping up.

Clean nonetheless. Adds to the already-present Bokeh.
 
Well, the most ignored rule in image troubleshooting with 35mm adapters is to rule the camera out first! I've been caught several times in the past trying to fix something that was completely a cam issue. In this case, without reproducing the test sans adapter, I'd have to suspect the diffuser wonky setup.

The manufacturer overnighted the production trials ... so with luck I'll have the diffuser taken care of for this weekend. I'm also being forced to zoom about 15-20% more than I should have to, again due to the current hack job. All I can say is that if it looks good now (minus the CA) the production version is really going to rock.

The test does give a good indication of noise levels and sharpness though, which was the primary objective.

Btw, the A1 focus and zoom presets are a great tool for adapter users....just attach, press two buttons to get your zoom/focus and you're shooting...cool.
 
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guskersthecat said:
Edit: You will see some CA in the first part of the clip (side of man's head). This is partially an issue with the proto diffuser which will not affect the production version. I also have a sneaky suspicion that the A1 lens is a player in this. The H1 is fairly well known for CA pretty much under the same circumstances. It will be interesting to see how this plays out in the A1 group.
Click to expand...

It looks pretty good, but yes, the CA is a bit distracting. I look forward to more. :)

btw, as far as I can tell, the A1 on its own has little to no CA overall.
 
great footy Dennis,

I was worried if a vibrating setup will induce mpeg artifacting because of the mpeg-codec structure. but now I am relived. I will bring out my gettho 35 shoebox adaptor tomorrow and shoot something.

btw elton, i was shooting in an art gallery with the A1 and the CA caught my eye in post, I was wide out but I notice purple fringing outline by the gold pillar I was shooting. It was there but it was not important because it looked great regardless.

CA whatever I love my A-1,
 
There did not appear to be any particular audio issues caused by the Brevis, while listening on a laptop full vol. I will listen on some decent headphones later to confirm, though I imagine with an external mic, etc, nothing to be concern about.
 
It is being referenced in Dennis' footage, the blue tinge around the hair.

The link i posted, look at the images on the right, the bottom image of the building, it is particularly pronounced on the right side of the roof. Think of getting an RGB image, and moving the the red channel 1 pixel to the right and the green channel moved the left, and blue no change. The image gets a smeared look. Probably a bad explanation...
 
It doesn't look like CA though. That usually comes in pairs of two colors (often magenta and green). Looks like something that happens on the ccd or in the processing of the signal...
Maybe anyone else can try to shoot branches in front of a blownout window? I haven't seen this ever before, with any cam....
 
Actually, the worst I've seen is from an XL2 which was using I believe the xl1s 16x manual lense. We were setting back focus (infinity), full zoom, using tree branches and the CA was huge.

There's a thread over at dvinfo on this, with more clips. It definitely needs more testing...and it does go away by dialing in stop or two. I should stress that I have not tested on other presets, and I'm using CINE. V tweaked with NR on low, and gain at -3db.

Not posted in the original adapter footage is a pan from right to left. The halo grows as the highlights on the man's head move closer to the edge of the frame...consistent some sort of chromatic lens issue. There are few lenses that are at their best wide open, so no huge surprise here.
 
Interesting findings Dennis. This seems to provide a possible theory to something that puzzled me on a project I had about 7-8 years ago, using the Panasonic AJ-D700. The project, all shot on a greenscreen, was pumped with a lot of light. We found that the talent had a similar band on the left side, not blue, it was a darkening band about a pixel or so. Perhaps the exposure balance of the light on the greenscreen and the talent was causing this on the encode to DVCPro(25). The importance of good lighting, balanced, and knowing the technology. Always learning, trying...
 
Well, good news on the blue meanies. Basically there are a two items at play here from what I can gather from testing. One is that zebra's are turned off on the LCD display when peaking is enabled for focus assist. It's very easy to forget you have peaking on. Also, it looks like NR1 option must be used with some caution as turning it off, and correcting exposure fixed the issue...whew.
 
Inability to have both zebras and peaking is really annoying on the XHA1.

But, definitely turn NR1 off. It's just asking for trouble; even on the LOW setting it can cause ghosting in your images. But are you saying that NR1 was causing the blue meanies? Can you get them to show up with NR1 enabled, and disappear just by turning NR1 off?
 
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