DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Panasonic DV / MX / GS series Assistant (https://www.dvinfo.net/forum/panasonic-dv-mx-gs-series-assistant/)
-   -   some tests on my NV-MX500EG (https://www.dvinfo.net/forum/panasonic-dv-mx-gs-series-assistant/21243-some-tests-my-nv-mx500eg.html)

Mattia Visintini February 12th, 2004 07:09 AM

some tests on my NV-MX500EG
 
After surfing these forums for some time, to help me decide which camera to buy, finally I decided for the mx500....(i would have chosen the dvx100... but my bank account wasn't thinking the same way ;-) )

Well, my PANA just arrived two days ago, and I decided to put it to the test immediately.
For the moment i concentrated on DOF and the differences between frame and normal mode, which are the ones that really interest me most.

Regarding frame vs interlaced, I was expecting a lot more of a difference in resolution... in the truth i found them almost identical, being able to see the resolution loss only while closely inspecting freeze frames on my computer.... During playback, it isn't so easy to spot. (TESTS BELOW)

For the DOF, I found out that it is possible to reduce it to some degree.... as long as the zoom is set to minimum 3X.... it's not much, but hey how much does the lens inside the pana cost????

here are the tests:
(they are all in PAL 16:9 format)

DOF tests:
http://users.skynet.be/divinefilms/DPOF1.jpg
http://users.skynet.be/divinefilms/DPOF2.jpg
http://users.skynet.be/divinefilms/DPOF3.jpg

frame vs interlaced tests:
http://users.skynet.be/divinefilms/NORMALFRAME1.jpg
http://users.skynet.be/divinefilms/NORMALFRAME2.jpg
http://users.skynet.be/divinefilms/NORMALFRAME3.jpg

other frame grabs (all in frame mode):
http://users.skynet.be/divinefilms/pan1.jpg
http://users.skynet.be/divinefilms/sunset.jpg
(note the distortion in the horizon in this one..... )
http://users.skynet.be/divinefilms/zoom.jpg

Tommy Haupfear February 12th, 2004 09:47 AM

Nice frame grabs.

I see a little loss in resolution with frame mode but thats to be expected.

Do you have any interlaced vs. frame mode with a moving subject?

Guy Bruner February 12th, 2004 10:15 AM

Nice frame grabs, Mattia. These correspond to what I have found with respect to the resolution of frame mode...it is quite good and hardly discernable from 60i. Where I have seen the most deviation in quality is with very low light levels. Frame mode is much grainier than normal mode in low light even with the 1 F stop gain in frame mode. I presume you didn't change any of the exposure settings when you switched between normal and frame? That would explain why your frame mode grabs are brighter.

Tommy Haupfear February 12th, 2004 10:22 AM

Quote:

That would explain why your frame mode grabs are brighter.
You mean darker, right? My GS100 is noticeably brighter in interlaced versus frame mode.

Mattia Visintini February 12th, 2004 12:32 PM

Tommy, I did it on purpose to shoot only static images.... it is quite difficult to judge the resolution of interlaced mode with moving subjects..... those field lines really garble things up a bit! (at least for freeze frames, in playback its easier)

As for the loss/increase in brightness i noticed it also.... frames look a bit brighter in frame mode.
Having locked the exposure settings in both tests, i really don't know what to think about it.
I'll have to do some tests with some other subjects to see what is really happening.

btw Guy, what's the 1-F stop gain difference you are talking about?

Tommy Haupfear February 12th, 2004 01:27 PM

In this frame interlaced looked brighter to me.

http://users.skynet.be/divinefilms/NORMALFRAME2.jpg

John Gaspain February 12th, 2004 01:50 PM

Great shots! You are in a very cool area to be able to just pull that out.

Good DOF, Im gonna have to try the 3x trick.

Thanks for the beatifull pics

Guy Bruner February 12th, 2004 01:59 PM

Based on what I saw, all the frame mode pix were quite a bit brighter than the interlaced. According to technical information posted here before on frame vs. interlaced mode in DV camcorders, frame mode has about 6 dB more gain due to the way the pixel information is interpolated as compared to interlaced mode. I have not seen that in my frame grabs, but it is clearly observable in Mattia's.

Mattia,
Did you lock your exposures in interlaced mode and hold that in frame mode? If so, the camera probably couldn't auto adjust the exposure...just a guess.

Here's the link I mentioned above.

Mattia Visintini February 12th, 2004 02:28 PM

Guy, I am sure that in pics 1 and 3 i shot first in frame mode, locked the exposure and then switched to normal mode. I am not sure if pic 2 was first done in the opposite way... (Tommy, perhaps this is why there isn't much difference in that case? I truly don't know.......)
I didn't really notice the differences in brightness at first, since I didn't expect any (nor had i read anything about it). It is something i definitely have to find out. Tomorrow i'll try to do some more tests just for this. I'll post them as soon as i can.

John, it may be obvious, but i forgot to write that you'll need some pretty dense ND's (at least with sunlight) to open the iris as much as you can.... the ideal being on the "open" setting. Anything less will start putting everything in focus....

Mattia Visintini February 12th, 2004 02:32 PM

Guy, oops i missed your link on my first reading....
thanks a lot!
it's a very interesting article!

Allan Rejoso February 12th, 2004 07:26 PM

Tommy, are you not referring to Procinema mode instead (the frame mode which is dimmer than normal interlaced)?

Tommy Haupfear February 12th, 2004 07:52 PM

Allan, correct as usual. I rarely use just the frame mode without being in Pro Cinema and hadn't thought about all the factors that go into making this mode.

Guy Bruner February 12th, 2004 08:30 PM

Allan or Tommy,
This is a little OT, but do either of you know what the light sensitivity specs are for the DV953/MX5000? I know low light is 15 Lux, and I believe that is at +18 dB @ 1/60 in normal mode. The manual says standard illumination is 1400 Lux, but is that at F4, F8...at 1/60, normal mode?

I'm trying to establish the ASA value for the DV953. I've sorta got it using my Canon AE1 Program's AE modes but I want to compare this to some reference info.

Mattia Visintini February 13th, 2004 07:24 AM

here are some new test i did...

http://users.skynet.be/divinefilms/TEST1.jpg
http://users.skynet.be/divinefilms/TEST2.jpg
http://users.skynet.be/divinefilms/TEST3.jpg
http://users.skynet.be/divinefilms/TEST4.jpg
http://users.skynet.be/divinefilms/TEST5.jpg

results are consistent with the 6dB's (perhaps a bit less) increase in brightness, by switching from normal to frame mode.
frame mode grabs also show some more grain, noticeable on darker, or uniform areas of colour... just as Guy said.

Guy Bruner February 13th, 2004 08:00 AM

Mattia,
Beautiful shots! I'm going to have to visit there one day.

Your frame mode grabs are cleaner than mine. I suspect that is due to the added resolution in PAL. However, I really only notice a loss in resolution at very low (15 Lux) light levels. Otherwise, I'm quite satisfied with the frame mode quality. Video is very good and looks exceptional in 16:9. When uprezzed to WMV 9 HD, it is stunning. Thanks for posting those comparisons.

Mattia Visintini February 13th, 2004 09:42 AM

Guy,
regarding you search for the ASA sensitivity, what value did you find?
Comparing it with my nikon reflex camera, i found it out to be around 50 ASA.... but i am not really sure about the method....
i have a 300mm f4 fixed telephoto lens, so i pointed my mx500 to a fairly uniform overcast sky with an equivalent amount of zoom, setting the shutter priority to 1/50 and finding a spot where the aperture would go to f4.
Then i took the nikon, set it at f4, aimed it a at the same point and then changed the ASA settings until the AE program gave me a shutter time of 1/60 (which anyway is less than 1/4 of f-stop difference from 1/50).
...in theory it should be correct (approximately).

not strictly on topic, but does anyone know the dynamic range which can be captured in a shot? I mean the f-stop difference between the darkest, and lightest discernible detail?
I'd like to do some tests on it, but i need to find a decent light meter first...

Guy Bruner February 13th, 2004 09:52 AM

Mattia,
Interesting that you took the same approach to identify ASA!! However, I did this a little differently.

I used my AE1 Program with its F1.8 50mm lens because I wanted the two lenses to be roughly equivalent (the 953 is F1.7 in video). Then, I basically used the same approach. I set the shutter to Auto (1/60), pointed the 953 at a light source that completely illuminated the CCD, then shifted to manual and checked the iris. Then, I set the Canon to 1/60 shutter, pointed at the same light source and adjusted ASA until the iris was roughly the same. I get between 100 and 200 ASA with this, but want to repeat the tests a few more times at different light levels to validate.

Guy Bruner February 13th, 2004 10:27 AM

Ok,
I have redone my ASA tests in indirect natural light using off white backgrounds (nonglossy). I measured one background at F8, 1/60 (both cameras)...this resulted in ASA80 on the Canon AE1 Program. The second background was at F2.0, 1/60 on both cameras...this also resulted in ASA80 on the Canon. BTW, this was done with no filter or lens shade on the DV953.

I have to conclude that the DV953 has a light sensitivity similar to ASA80 film.

Mattia Visintini February 13th, 2004 11:22 AM

Thanks for the results Guy!
I also repeated the test a couple of times, this time also with a 20mm f2.8, and the results are similar to yours.... in my case they oscillate between 64 and 80 ASA.
Anyway to be really sure I will do them again with a professional light meter a friend of mine has, as soon as possible (unfortunately he's away). Then i'll also try to find out what f-stop range the ccd's can capture.... it's something i'm quite interested in.

Guy Bruner February 13th, 2004 11:29 AM

Mattia,
A good light meter in incident mode would be a more accurate check. But, I believe we can safely say the sensitivity is approximately ASA80.

As an aside, in Gain Up mode, each 6 dB is equivalent to doubling the ASA rating at 1/60 shutter, IIRC. So, +6 dB would be ASA160, +12 -- ASA320, and +18 -- ASA640. I'd say the 953/500 is pretty sensitive in low light.


All times are GMT -6. The time now is 10:51 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network