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-   -   Nikon lenses with adaptor for wildlife? (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/67982-nikon-lenses-adaptor-wildlife.html)

Steve Williams May 23rd, 2006 02:37 AM

Nikon lenses with adaptor for wildlife?
 
Nikon lenses with adaptor for wildlife?

Got GY-HD101 with a Nikon adaptor that allows me to use Nikon stills 35mm photographic lenses. Great thing about this is that a 100-300mm zoom turns into the photographic equivalent of a 700-2000mm zoom; roughly.

But I'm having problems. I bought a Sigma 100-400 auto focus Nikon mount zoom. Cost around $1,650. When I zoom in slowly, the picture jumps up and down. Also, when zoomed right in and locked-off on tripod, when I play back footage I can see it drifting in and out of focus. Even though it is not being used in AF as it can't be, but it is jumping in and out every second, or twice a second. Only a fraction, but at that length the depth of field is so narrow you can spot it a mile off. I've since returned the lens so wondered if anyone can recommend a decent manual focus zoom that won't do any of these two things?

Of course, these two issues would not be faults in stills photographic land, but for video the lens is pretty much useless.

Andrew Young May 23rd, 2006 04:19 AM

Hi Steve,

I've used the adaptor with a 50-300 Nikor all manual lens, as well as a 55 macro. Focus holds fine once set but does not hold well over the range of the zoom. I'm also having some issues with internal reflection that I can't quite figure out. The system definitely works, but not without some finesse. Auto focus lenses may not be the best choice, as they never seem to focus as nicely as manuals, in my experience.

Daniel Weber May 23rd, 2006 05:08 AM

Andrew,

I have a question about mounting lenses to the Zoerk adaptor.

Do you need to use a rail system? I have a Nikon 80-200mm 2.8 lens that I would like to use on the HD100, but it is a very heavy lens.

I would like to know how you mount your lenses.

Thanks,

Dan Weber

Doug Harvey May 23rd, 2006 10:34 AM

I use the Les Bocher Nikon adaptor with a Sigma 70-200 F2.8 APO. It seems to work rather well, depending on the circumstances. For non moving subjects, the shallow DOF range can be a great advantage, but for close ups with a moving subject, a constant eye on focusing is required. It's a big step from the Standard lens, so it would take some practice to get the finesse needed to operate the combination smoothly.

Focusing holds up fine once set, but does not hold well over the entire range of the zoom, so going from min to max zoom range you will have to keep a constant eye on your focus, using the focus assist helps, or having a good location monitor would be an asset.

If you use the Nikon adaptor combination without a rail system or some sort of stabilizer bracket the lens combination will flex causing distortions in your footage. I also I'm having some issues with reflections, so more time is needed to try to figure out a remedy.

I have also used a 2X doubler with the Sigma 70-200 F2.8 APO that produced interesting results, but the shallow DOF is more noticable with this combination.

Sorry, I had to remove the clip due to bandwidth restrictions.

Steve Williams May 23rd, 2006 10:53 AM

Dosn't the rail support system stop flexing?

Doug Harvey May 23rd, 2006 11:08 AM

I don't have a rail system, but a bracket, it does a good job of keeping everthing in place, no flex, but alignment for the adapter - lens combo is critical, more so with the 2X doubler.
I would have to say that once the alignment is completed, you do get a nice picture except for the reflections.

Andrew Young May 23rd, 2006 01:13 PM

Quote:

Originally Posted by Daniel Weber
Andrew,
I have a question about mounting lenses to the Zoerk adaptor.

Do you need to use a rail system? I have a Nikon 80-200mm 2.8 lens that I would like to use on the HD100, but it is a very heavy lens.

I would like to know how you mount your lenses.

Hi Daniel,

I have the Chroziel rod and mattebox system. I use the rods with a bracket to support my 50-300. I don't remember where I got the bracket - it was many years ago, but the lens just rests on it. Regarding your 80-200, if it has a tripod mount on it, it should probably be supported. Although you can compare the size and weight to the Fujinon 13x. That is a pretty big lens which does not need support. The 50-300 definitely does. Good luck.

Andrew Young May 23rd, 2006 01:17 PM

Quote:

Originally Posted by Doug Harvey
I'm having some issues with reflections, so more time is needed to try to figure out a remedy.

Hi Doug,

Can you describe your reflections issue? I am having issues that appear to be internal reflections. They appear as red streaks that come and go in the lower frame depending on the light. I'm curious if you are experiencing the same.

Doug Harvey May 23rd, 2006 05:14 PM

If you watched the video,( it's just a Web Version), at certain times you will see red streaks in the lower frame of the picture, at first I thought it was tall grass but it seems to be a reflection that goes all the way out to the geese in the center on my original version.

The close up of the frog has blue abberations in the shaddows, but the distant shot of the frog has red abberations on his leg.

I was not using any kind of filter,and just the standard lens hood on the Sigma lens. It was all natural lighting during the late morning. This red streaking seems so far only to appear in only extreme high contrast situations in the lower frame.

Andrew Young May 23rd, 2006 09:03 PM

Quote:

Originally Posted by Doug Harvey
If you watched the video,( it's just a Web Version), at certain times you will see red streaks in the lower frame of the picture,

Yep, that's the same problem I'm having. Very annoying. It looks like an internal flare or reflection. I'm going to contact Zoerk and see if they have any ideas.

Ron Armstrong May 23rd, 2006 09:33 PM

For your long lens stabilization, you will need a RONSRAIL Lens Support. Although the website doe's not show one, the RONSRAIL will fit the JVC GY HD 100.
Take a look at my website to see some long lens applications and various adapters used for those lenses.

Joel Aaron May 24th, 2006 10:21 AM

Quote:

Originally Posted by Andrew Young
They appear as red streaks that come and go in the lower frame depending on the light. I'm curious if you are experiencing the same.

I've seen that on my setup too. I haven't figured out exactly what's causing it yet... but it's always at the bottom of the frame. Maybe there's a focal length or aperture that produces it more. Let us know what Zoerk says.


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