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-   -   Has anyone used the Z7 with till Nikon lens yet? (https://www.dvinfo.net/forum/sony-hvr-z7-hvr-s270/116532-has-anyone-used-z7-till-nikon-lens-yet.html)

Ofer Levy March 7th, 2008 09:56 PM

Has anyone used the Z7 with till Nikon lens yet?
 
Hi all,

I am hoping to use the Nikon 80-200 f2.8 on the Z7 using a Nikon adapter made by Mike Tapa. (haven't bought the lens yet)

I realise though that there will be no focusing aid so I will have to relay on my eyes and judgment to get an absolute focus. Working with a telescope lens from a short distance with a shallow DOF might make focusing very difficult with nothing to relay on.
Does anyone have any idea how to solve this?

Thanks!

Ofer Levy
Nature photographer
http://www.oferlevyphotography.com

Brian Standing March 8th, 2008 08:03 AM

Measuring tape?

Ofer Levy March 8th, 2008 08:27 AM

Quote:

Originally Posted by Brian Standing (Post 839156)
Measuring tape?

Great joke!!

Some serious advice would be appreciated...

Mika Tertsunen March 8th, 2008 09:30 AM

Quote:

Originally Posted by Ofer Levy (Post 839163)
Great joke!!

Some serious advice would be appreciated...

Well thatīs what professional cinematographers have been using for the past 100 years and still do. Quite serious, I would say...

Ofer Levy March 8th, 2008 09:42 AM

Quote:

Originally Posted by Mika Tertsunen (Post 839196)
Well thatīs what professional cinematographers have been using for the past 100 years and still do. Quite serious, I would say...

I am new to this business but somehow feel that there must be a more "modern" way than a measuring tape....(-:
I am going to make wildlife films - especially about birds, so a measuring tape is not an option....

Brian Standing March 8th, 2008 02:47 PM

Well, it wasn't meant as a joke. Still SLR camera lenses have mechanical focus rings that are very precise. If the focal distance on the lens says that it's in focus at 12 feet, then that's what's in focus. This is unlike servo-motor prosumer video lenses that just spin endlessly, making it difficult to reproduce precise focus distances.

Under some wildlife shooting scenarios, a measuring tape would be appropriate. For example, I am currently using a film camera to shoot birds on a feeder. I have measured out the precise distance from my lens to the feeder and set the focus based on the hash marks.

Won't work in every situation, obviously, but in some circumstances trusting a measuring tape is more reliable than trusting your eyes.

Ofer Levy March 8th, 2008 04:44 PM

Quote:

Originally Posted by Brian Standing (Post 839309)
Well, it wasn't meant as a joke. Still SLR camera lenses have mechanical focus rings that are very precise. If the focal distance on the lens says that it's in focus at 12 feet, then that's what's in focus. This is unlike servo-motor prosumer video lenses that just spin endlessly, making it difficult to reproduce precise focus distances.

Under some wildlife shooting scenarios, a measuring tape would be appropriate. For example, I am currently using a film camera to shoot birds on a feeder. I have measured out the precise distance from my lens to the feeder and set the focus based on the hash marks.

Won't work in every situation, obviously, but in some circumstances trusting a measuring tape is more reliable than trusting your eyes.

Thanks for that Brian,

How about some kind of a small magnifying lens attached to the view finder and giving a much bigger image which makes it is easier to focus. SInce I also have the LCD I can use it for making the composition.
I realise that if there is really no way to get a perfect focus and I only relay on guessing - I am stuck with a camera which is totally useless for me...)-:

Mika Tertsunen March 8th, 2008 05:19 PM

Quote:

Originally Posted by Ofer Levy (Post 839348)
Thanks for that Brian,

How about some kind of a small magnifying lens attached to the view finder and giving a much bigger image which makes it is easier to focus. SInce I also have the LCD I can use it for making the composition.
I realise that if there is really no way to get a perfect focus and I only relay on guessing - I am stuck with a camera which is totally useless for me...)-:

You need to remember that the viewfinder is not optical, so magnifying that would just make the pixels larger. I guess you might be better off by using the lcd which has a greater pixel count together with the focus assist function.
Of course if there is a way for you to use an external hd monitor, that's obviously the way to go.

Mark Williams March 8th, 2008 08:03 PM

I have used a borrowed laser rangefinder before. It gives very accurate measurements. Just don't put the red dot near any animal's eye.

Ofer Levy March 8th, 2008 08:55 PM

Thanks for your input so far guys!
I am not sure about the laser thing - looks a bit too complecated. An external HD LCD looks like a more interesting option for me. I have a Toshiba laptop with HD LCD - will this work?

Greg Hartzell March 9th, 2008 06:46 AM

Why not a 60" plasma? That should allow you to focus properly!

Ofer Levy March 9th, 2008 07:16 AM

Quote:

Originally Posted by Greg Hartzell (Post 839530)
Why not a 60" plasma? That should allow you to focus properly!

I am not sure I appreciate this VERY clever humor. I need advice not clever comments.
Thank you.

Steve Phillipps March 9th, 2008 02:17 PM

Just practice really. On broadcast cameras it helps to turn the viewfinder peaking right up, not sure if these domestic cams have one though. You'll probably find it extra difficult to follow focus in progressive mode as the image blur makes it always look out of focus with moving targets.
Steve

Christopher Ruffell March 9th, 2008 02:31 PM

They're rightm, and giving you the right answer, which is why the pseduo-sarcasm still persisted. Here are common ways to get focus:

a) Measuring tape (difficult for one man shoots) and setting marks on the ground and on the lens.

b) Use a good HD monitor on set that'll provide a sharp image and eye balling it.

c) If the Z7 has a 'zoom focus' button (not sure of the correct name), where it blows up the image so you can focus, use it. I'd suggest holding a 8"x11" sheet of paper with small 12-pt print on it where you want the focus - if you can get that in focus (eye balling it), you're in business. If the Z7 has a 'zoom focus' button, sounds like that'll be your best friend.

I use b) and c) when I shoot, and I shoot with a Nikon 35 lens on an HV20 - fully manual as well. It's been working so far. Having a good HD monitor on set is priceless.

Greg Hartzell March 9th, 2008 04:34 PM

All Apologies!
 
Ofer,

Yes, to clarify my point, you need a high resolution monitor amd honestly, the bigger the better (at least as far as I'm concerned, as a side note, if you blow up an hd image on a really large screen, this will make any focus problems painfully obvious). There are professional lcds that allow you to zoom up in on an edge, like a digital slr will allow you to do, but I doubt these will be with in budget, so I don't think that will work. I'd be wary of laptop lcds, if you do go this route, adjust properly, but most laptop lcd screens wont be high enough resolution (do you know the res of yours off hand?). Also, there might be monitoring software (adobe onlocation?) that may allow you to zoom on an edge to focus.

To add on the various measuring tape comments, the reason why this is still used, is because it is the most accurate way to focus, giving that you have a lens with accurate focus scales on it. With a film camera, the optical viewfinder is just an apparent representation of an image, focus sharpness isn't exactly accurate.

I'd be really careful of what lens you buy for this as well. I'm not sure about the lens you mentioned here, but many of the lesser digital slr lenses out there fringe quite easily under high contrast conditions. I'm not sure why you need such a zoom range, but maybe a shorter range zoom would be a better comprise.


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