DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Sony HVR-A1 and HDR-HC Series (https://www.dvinfo.net/forum/sony-hvr-a1-hdr-hc-series/)
-   -   Depth of field on A1u? (https://www.dvinfo.net/forum/sony-hvr-a1-hdr-hc-series/67629-depth-field-a1u.html)

Joff B. Rein May 18th, 2006 07:12 PM

hej, here are some cheap findings in search for dof, only not with a1 :(

focus and stability are my problems

bothe are made with hdc-1, auto-mode except manual focus,


first video; both poor light and good light conditions, winter in sweden with letus lens-adaptor and canon fd 50mm f1.4 lens, .wmv 1500kb/s, 17mb. 1.38min.

http://www.streamload.com/xid/sweden_test.wmv


second video , my garden in amsterdam and neighbour-cat, medium light condition with
sony 0.6x wide-lens / close up first half manual focus, second half autofocus, .wmv hdv-stream, 99mb, 4.19min

http://www.streamload.com/xid/poes_hdv.wmv

Stu Holmes May 18th, 2006 09:15 PM

Quote:

Originally Posted by Frank Howard
I owe you a beer Stu!

Ooh dangerous thing to say Frank... i can never settle for just one !! ;-)

Floris - respect is due to you. Anyone who is aware of 18% gray cards and what they're for and how camera light meters are calibrated to assume the world is 18% gray (most of the time) gets my vote....

So when Frank buys me that beer, i'll make him buy me two, and iŽll give one to Floris !!

Michael Stowe May 18th, 2006 09:53 PM

Quote:

Originally Posted by Stu Holmes
Ooh dangerous thing to say Frank... i can never settle for just one !! ;-)

Floris - respect is due to you. Anyone who is aware of 18% gray cards and what they're for and how camera light meters are calibrated to assume the world is 18% gray (most of the time) gets my vote....

So when Frank buys me that beer, i'll make him buy me two, and i´ll give one to Floris !!

Hey now...I have to 18% gray cards ;-) Does make quite the difference IMHO Expecially in my Nikon D100 days

Frank Howard May 18th, 2006 10:36 PM

I suspect a plot to turn me into a poor and wretched drunk.

I'm down.

Alexander Karol May 18th, 2006 11:58 PM

Joff, very nice videos. I am wondering if you could share some pictures of your camcorder with the lenses. I would love to be able to achieve similar results.

I am particular interested in the Sweden video you composed. Also, what filter did you use for the last shot with the women profiles? I really enjoyed the dramatic feel to it.

Floris van Eck May 19th, 2006 02:03 AM

[/qu
Quote:

Originally Posted by Joff B. Rein
hej, here are some cheap findings in search for dof, only not with a1 :(

bothe are made with hdc-1, auto-mode except manual focus,


first video; both poor light and good light conditions, winter in sweden with letus lens-adaptor and canon fd 50mm f1.4 lens, .wmv 1500kb/s, 17mb. 1.38min.

http://www.streamload.com/xid/sweden_test.wmv

Can you tell me something about this lens adapter? Where can I buy it and how does it work? Does it also work with Nikon objectives? Like Alex asked, do you have a picture with this adapter and lens attached to your HC1?

Any feedaback would be greatly appreciated!

Stu Holmes May 19th, 2006 10:45 AM

Quote:

Originally Posted by Joff B. Rein
hej, here are some cheap findings in search for dof, only not with a1 :(

focus and stability are my problems

bothe are made with hdc-1, auto-mode except manual focus,


first video; both poor light and good light conditions, winter in sweden with letus lens-adaptor and canon fd 50mm f1.4 lens, .wmv 1500kb/s, 17mb. 1.38min.

http://www.streamload.com/xid/sweden_test.wmv


second video , my garden in amsterdam and neighbour-cat, medium light condition with
sony 0.6x wide-lens / close up first half manual focus, second half autofocus, .wmv hdv-stream, 99mb, 4.19min

http://www.streamload.com/xid/poes_hdv.wmv

Yes in my opinion a substantial amount of both videos, the subject is simply out of focus. The cat is sometimes in focus, sometimes out. The camera (when on autofocus) sometimes selected the background to focus on (this is common). Also at times, the cat is closer than the minimum focus-able distance. All these cams have a minimum focus distance. Telemacro would help a lot as this will let you focus really close.

The Sweden video - again, most of the time the women were just out of focus. In this instance, i'd auto focus as the camera should be able to hang onto that subject fine. Or, zoom in, autofocus, then flick to manual focus to hold it if you're concerned the cam will lose focus.

nice 'feel' to the vids nevertheless.

Floris van Eck May 19th, 2006 11:31 AM

I personally find manual focus the most convenient to use but it will take some practices to apply it to moving subjects. But like Stu mentioned, I really like the feel of the Swedish footage. I guess it is related to the Canon lens.

Mikko Lopponen May 21st, 2006 04:01 AM

Quote:

Originally Posted by Michael Stowe
Technically there is no aperature setting on the A1 or atleast it does not show it.

Six stops from the right and aperture is max open. 1.8.

Stu Holmes May 21st, 2006 09:12 AM

Quote:

Originally Posted by Michael Stowe
Technically there is no aperature setting on the A1 or atleast it does not show it.

It *will* show it on playback.
In TAPE mode, select :
DATA CODE
then:
CAMERA DATA.

It will show tech info on replay on-screen including :
- aperture (f-stop)
- shutter-speed
- white-balance mode
- amount of gain dB
- whether camera was in Auto-exposure or Manual exposure mode.

Aperture will not get smaller (i.e. smaller physical aperture/iris, BIGGER f-stop number) than f4 on HC1 unless there's a LOT of light. It switches in internal ND filters instead as long as it can.

But Depth-of-field for these cams with small sensors is pretty good so i wouldn't worry too much.

Floris van Eck May 22nd, 2006 04:37 AM

Does anyone else have experience with 35mm lens adapters? The premise of those adapters looks promising. But as I have never worked with them, I do not know the advantages and disadvantages. I am also not sure if I want to spend like $300-600 on such a system and lenses.

Frank Howard May 22nd, 2006 03:51 PM

I always heard the Sony data code isn't always accurate...

Stu Holmes May 22nd, 2006 05:33 PM

Quote:

Originally Posted by Frank Howard
I always heard the Sony data code isn't always accurate...

its accurate for shutterspeed and gain and exposure mode and whitebalance.
The only item that is of some debate, and this is anyway only on certain Sony cams is the reported aperture. But am pretty certain that this value is accurate on these cams we're referring to. You need to remember that the 'aperture' beyond f4 is most of the time controlled by inline ND filters and therefore its no longer a genuine physical aperture change.

All other items, an most likely aperture too, are accurate, and are useful in reviewing footage.

Frank Howard May 23rd, 2006 09:21 AM

Of course, if the chart at http://hdvforever.com/hdv/exposure/ is accurate, the system of using f-stops is seriously curtailed as the aperture settings available are: 8, 6.8, 5.6, 4.8 and then 4, which is where you start getting the ND filters jumping into play.

Nick Outram May 23rd, 2006 10:08 AM

Dof
 
Hi,

I have been experimenting with my HC1 modes and find that the 'Portrait' mode can be used to reduce DOF. I suspect it simply opens up the Iris to the lowest 'F' value allowed for the given lighting conditions. Conversely there is a 'Landscape' mode that may work to increase DOF although I have not tested this. I have a Canon SLR and it has similiar functions. For the HC1 it is explained on page 44 of the user manual.

[For shallow DOF: In brighter light I would add a couple of ND filters onto the front. I have found the optimum background blur to be achieved by zooming in at least half way on the slider -and ideally as much as possible- and placing the subject 1/3 distance to background...]

Finally, here is an online DOF calculator to have a play with:

http://www.dofmaster.com/dofjs.html


Regards, Nick.


All times are GMT -6. The time now is 08:58 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2025 The Digital Video Information Network