What's the consensus on 5.8/f1.9? Has anybody done any serious tests? at DVinfo.net

Michael Maier · November 1st, 2008, 09:40 PM

Has anybody done any serious tests for performance at 5.8 full wide with f1.9 fully open?
What is the consensus? Avoid like the plague, acceptable, very good? Details?
Thanks.

Perrone Ford · November 1st, 2008, 10:45 PM

Quote:

Originally Posted by Michael Maier

Has anybody done any serious tests for performance at 5.8 full wide with f1.9 fully open?
What is the consensus? Avoid like the plague, acceptable, very good? Details?
Thanks.

Great question! I just got finished running some tests. I'll post the photo evidence in a few moments. I've attached a photo of the setup.

Basically the test was:

Set up a background and place a resolution test on it. In this case, I chose a 5 dollar bill. US money has some very intricate work that will show up detail well.

I then zoomed the camera out fully, opened up the iris fully, and swung just enough light on it to get a good exposure. I moved the camera in closely enough to fill the frame, focused with the expanded focus and peaking, and hit record.

I'm pretty curious to see how "bad" the camera is wide open and fully zoomed out. I think I will also do a test of this af F16 with no ND filters to see how bad it is in the far end of the iris.

Perrone Ford · November 1st, 2008, 10:56 PM

Ok,

Here is the photo evidence...

Bob Jackson · November 1st, 2008, 11:15 PM

not bad for a 1.5 to 2 x reproduction.

Perrone Ford · November 2nd, 2008, 01:10 AM

I'd say the performance is more than acceptable. In a common master or wide shot, this level of sharpness would be AWFULLY impressive. We are resolving details on less than 1 mm in this shot. Taking a wide shot of an outdoor scene, or an interior room, this is going to look razor sharp.

When I get a chance, I'll replicate down at between F16 and closed.

Jon Sands · November 2nd, 2008, 08:09 AM

Perrone, I'd just like to thank you for all the time you've spent on helping us/tests/etc. It's great!

Perrone Ford · November 2nd, 2008, 09:59 AM

Quote:

Originally Posted by Jon Sands

Perrone, I'd just like to thank you for all the time you've spent on helping us/tests/etc. It's great!

It's been my pleasure. I am learning right along with you guys.

Barry J. Anwender · November 2nd, 2008, 01:10 PM

Quote:

Originally Posted by Perrone Ford

Ok,

Here is the photo evidence...

Honest Ab is looking a bit weathered on your bill, guess it is understandable giving all the upheaval on Wall St. and in Banks.

Thanks Perrone for your tests. They are reassuring us that we have made a good investment:-)

Leonard Levy · November 4th, 2008, 05:02 AM

I would suggest that you try to frame the bill to take up the entire picture so you can see whether you are flat across the frame. Most aberrations will hit the corners first.

Perrone Ford · November 4th, 2008, 08:24 AM

Quote:

Originally Posted by Leonard Levy

I would suggest that you try to frame the bill to take up the entire picture so you can see whether you are flat across the frame. Most aberrations will hit the corners first.

I was holding the bill with two clips. I couls see I wasn't flat because the subject wasn't flat. I encourage you to pick up the ball and run with it. Let us know what you find.

Dean Sensui · November 4th, 2008, 08:36 PM

I'd help with the tests but after getting two of these cameras I don't have a $5 bill to shoot.

I'd have to do it with loose change... :-)

Peter Kraft · November 5th, 2008, 01:01 AM

Dean,
I throw my remaining 2 cents in ;-)

Tom Roper · November 5th, 2008, 09:12 AM

To give you the money I'd have to send you the bill.

Leonard Levy · November 6th, 2008, 12:01 AM

Perrone ,
What I meant by flat was not whether the bill was flat, but by not framing it all the way to the corners all you were testing was resolution in the center.
However it is generally likely that resolution problems will show themselves in the corners first.
This is generally true for low f stops at least, but may not be true in the case of of high f stops on the Ex-1 since the resolution issues there appear to be caused by diffraction around the small iris. (Actually is diffraction is the right word there? I'm tired so I might have the wrong term.)

I have looked at resolution wide open using a 4' chart and thought it was very even but I didn't think to try it at more closed f stops. I'll take a look if I get a chance. Clearly by f8 though it starts to suck big time.

Another question would be whether testing on such a small object , with such a close focus and zoomed way in, is a good way to test a lens. The lens is probably designed to function best at normal distances not for extreme CU's.

I don't mean to knock you for doing the tests as every piece of information helps, and I appreciate the effort. As somebody who used to test lenses for cine cameras in a rental house though I'm used to thinking about these issues. Its a good idea to think carefully about all the variables when testing so that you aren't wasting your own time and actually come up with useful results.

Lenny

November 1st, 2008, 09:40 PM	#1
Michael Maier Trustee Join Date: Apr 2005 Posts: 1,269	What's the consensus on 5.8/f1.9? Has anybody done any serious tests? Has anybody done any serious tests for performance at 5.8 full wide with f1.9 fully open? What is the consensus? Avoid like the plague, acceptable, very good? Details? Thanks.

November 1st, 2008, 10:56 PM	#3
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	Ok, Here is the photo evidence... Attached Thumbnails __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

November 2nd, 2008, 01:10 AM	#5
Perrone Ford Inner Circle Join Date: Nov 2006 Location: Tallahassee, FL Posts: 4,100	I'd say the performance is more than acceptable. In a common master or wide shot, this level of sharpness would be AWFULLY impressive. We are resolving details on less than 1 mm in this shot. Taking a wide shot of an outdoor scene, or an interior room, this is going to look razor sharp. When I get a chance, I'll replicate down at between F16 and closed. __________________ DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.

November 4th, 2008, 08:36 PM	#11
Dean Sensui Inner Circle Join Date: Oct 2001 Location: Honolulu, HI Posts: 2,054	I'd help with the tests but after getting two of these cameras I don't have a $5 bill to shoot. I'd have to do it with loose change... :-) __________________ Dean Sensui Exec Producer, Hawaii Goes Fishing

November 1st, 2008, 11:15 PM	#4
Bob Jackson Major Player Join Date: Sep 2008 Location: Republic of Vancouver Island Posts: 200	not bad for a 1.5 to 2 x reproduction.

November 2nd, 2008, 08:09 AM	#6
Jon Sands Regular Crew Join Date: Sep 2008 Location: Indianapolis, Indiana Posts: 107	Perrone, I'd just like to thank you for all the time you've spent on helping us/tests/etc. It's great!

November 4th, 2008, 05:02 AM	#9
Leonard Levy Trustee Join Date: Feb 2006 Location: USA Posts: 1,684	I would suggest that you try to frame the bill to take up the entire picture so you can see whether you are flat across the frame. Most aberrations will hit the corners first.

November 5th, 2008, 01:01 AM	#12
Peter Kraft Major Player Join Date: Nov 2007 Location: Europe Posts: 245	Dean, I throw my remaining 2 cents in ;-)

November 5th, 2008, 09:12 AM	#13
Tom Roper Trustee Join Date: Jun 2004 Location: Denver, Colorado Posts: 1,891	To give you the money I'd have to send you the bill.

November 6th, 2008, 12:01 AM	#14
Leonard Levy Trustee Join Date: Feb 2006 Location: USA Posts: 1,684	Perrone , What I meant by flat was not whether the bill was flat, but by not framing it all the way to the corners all you were testing was resolution in the center. However it is generally likely that resolution problems will show themselves in the corners first. This is generally true for low f stops at least, but may not be true in the case of of high f stops on the Ex-1 since the resolution issues there appear to be caused by diffraction around the small iris. (Actually is diffraction is the right word there? I'm tired so I might have the wrong term.) I have looked at resolution wide open using a 4' chart and thought it was very even but I didn't think to try it at more closed f stops. I'll take a look if I get a chance. Clearly by f8 though it starts to suck big time. Another question would be whether testing on such a small object , with such a close focus and zoomed way in, is a good way to test a lens. The lens is probably designed to function best at normal distances not for extreme CU's. I don't mean to knock you for doing the tests as every piece of information helps, and I appreciate the effort. As somebody who used to test lenses for cine cameras in a rental house though I'm used to thinking about these issues. Its a good idea to think carefully about all the variables when testing so that you aren't wasting your own time and actually come up with useful results. Lenny