How sharp should the Fujinon lens be? at DVinfo.net

Gabriel Florit · June 13th, 2008, 07:43 PM

Hey all,

After exactly one week as a proud EX1 owner I've a couple questions regarding the built-in lens. How should I dial in the lens to get the best sharpness, say at full telephoto? Common sense would dictate completely closed, right? But Doug Jensen of Vortex Media says f2.4 to f4, which I've tried.

Once I get my Extreme/Ultimate, will I see even sharper images? Or is this as sharp as it gets, in other words, is the Fujinon the "weakest link" in the Fujinon+LEX/LUL combination?

Next: what amount (if any) of CA am I to expect? Am I correct in assuming that CA is more likely to occur at full telephoto? Will it differ depending on what picture profile I'm using? Currently I use Bill's TC2 Cine1 for sunny days, and Sami's for overcast (Philip Bloom uses this one too).

I apologize if any of these questions betray my ignorance - I'm quite eager to learn all there is about camera work (like, I suspect, most of us here). Do my screenshots look sharp enough? Could sharpness be improved?

Greg Boston · June 13th, 2008, 07:49 PM

You'll want to avoid running wide open iris at full telephoto. Douglas is completely right about F2 to F4 because most lenses hit their 'sweet spot' about 2 stops down from wide open.

-gb-

Robert Young · June 13th, 2008, 09:41 PM

In Adam Wilt's review of the EX, he speaks very highly of the sharpness and overall quality of the Fujinon lens. I believe he says that there is no other lens in this price range that can touch it.
With 1/2 inch chips, low f stop, and any significant level of zoom/telephoto, the EX will have significant shallowing of the DOF, so focusing is critical and many people feel that auto focus will not do the job adequately.
You should be able to get a really sharp image from the EX.

Paul Newman · June 14th, 2008, 10:04 AM

Please forgive me if I'm totally off beam here but, surely, a camera with 1920x1080 native chips? if you want sharp, shoot at 1920x1080 - pixel to pixel, no down conversion.

Results I've viewed from 1280x720 material from my EX don't look great compared to the native HQ files at full rez.

(viewed on HD tube, real, glass, monitor )

Just my 3 euro's worth.

Paul

Tom Roper · June 14th, 2008, 03:25 PM

Quote:

You'll want to avoid running wide open iris at full telephoto. Douglas is completely right about F2 to F4 because most lenses hit their 'sweet spot' about 2 stops down from wide open.

I would ordinarily agree, but I'm not convinced of that on the EX1 specifically. It just seems like it's softening a little more than I would expect at the larger aperture openings.

But the other factor in this is contrast, which gives the appearance of resolution and could be mistaken for it.

I intend to put the EX1 through some Imatest lens testing as I did on the XH-A1 to reveal the lens stops that produce the highest numbers. Puzzling too, is the feeling I have that at some combinations of aperture and focal length, the EX1 lens may actually be sharper away from the center. That's not necessarily a bad thing if it was, nor am I certain if it is. But I have a suspicion about it I want to investigate.

Dennis Robinson · June 14th, 2008, 10:51 PM

Hi Gabriel,
I dont think these are sharp pictures at all. In fact they are far from what I get from my JVC111 and I know the EX1 can do a better job. I am keen to learn what the others have to say about getting a sharper picture, re. iris etc

Mathieu Ghekiere · June 15th, 2008, 02:32 AM

All four frames were shot outside... did you shoot with an ND filter on?
Maybe you have the famous back-focus problem...

PS: I don't think those frames are that bad.

Robert Young · June 15th, 2008, 03:13 AM

some of the problem looks like DOF issues to me. For example: the river/forrest frame- the shrubbery in the right lower foreground appears to be sharp, and the remaining elements at different distances are out of focus. My experience is that if you are zoomed out much, you will get shallowing of DOF below f 4.0. So the focal plane must be set deliberately and serve a compositional purpose, otherwise you should move to a higher f stop to bring more of the image into tight focus. For me, it is not always easy to see all of this in the LCD, so I use peaking and the DOF indicator to help me understand what I am doing, and help make me think more carefully about what I should be wanting to do with a particular shot.
To avoid DOF issues with the EX, you need to shoot wide, or shoot f8. On the other hand, shallow DOF is a brilliant tool that the EX offers, but seems a bit of a trick to gain mastery of.

Sverker Hahn · June 25th, 2008, 11:27 AM

At full telephoto, this lens is not performing well at lower f-stops. After getting some unusable shots I performed a simple check at different apertures.

Not until f=8 the resolution is acceptable in edges of the picture. f=11 - 16 is not as bad as f=1.9 - 5.6.

So from now on, I will use only f=8 with full telephoto.

At other focal lengths - I will check my lens some day soon ...

Sverker

Gabriel Florit · June 25th, 2008, 11:49 AM

Quote:

Originally Posted by Sverker Hahn

At full telephoto, this lens is not performing well at lower f-stops. After getting some unusable shots I performed a simple check at different apertures.

Not until f=8 the resolution is acceptable in edges of the picture. f=11 - 16 is not as bad as f=1.9 - 5.6.

So from now on, I will use only f=8 with full telephoto.

Interesting... I have definitely noticed an increase in sharpness when I go from, say f8 to ND2 + f4 or something like that. Maybe I should try the f2.4 - 4 area AND f8 - higher.

Dean Sensui · June 25th, 2008, 12:01 PM

In my experience f16 is awful. Probably due to diffraction.

Tom Roper · June 25th, 2008, 01:19 PM

I think this was shot with f2.8-3.4, 1/48th ND2, fully zoomed

It's fairly sharp at the center, but a shallow DOF.

Sverker Hahn · June 25th, 2008, 03:17 PM

Resolution might differ between cameras (?). Everybody should make their own series of tests, really.

Most lenses are best at f=5.6 - 8 for what I know.

And all lenses will perform worse at f=11 - 16 because of diffraction.

June 13th, 2008, 07:43 PM	#1
Gabriel Florit Regular Crew Join Date: Jan 2007 Location: Cambridge, MA Posts: 65	How sharp should the Fujinon lens be? Hey all, After exactly one week as a proud EX1 owner I've a couple questions regarding the built-in lens. How should I dial in the lens to get the best sharpness, say at full telephoto? Common sense would dictate completely closed, right? But Doug Jensen of Vortex Media says f2.4 to f4, which I've tried. Once I get my Extreme/Ultimate, will I see even sharper images? Or is this as sharp as it gets, in other words, is the Fujinon the "weakest link" in the Fujinon+LEX/LUL combination? Next: what amount (if any) of CA am I to expect? Am I correct in assuming that CA is more likely to occur at full telephoto? Will it differ depending on what picture profile I'm using? Currently I use Bill's TC2 Cine1 for sunny days, and Sami's for overcast (Philip Bloom uses this one too). I apologize if any of these questions betray my ignorance - I'm quite eager to learn all there is about camera work (like, I suspect, most of us here). Do my screenshots look sharp enough? Could sharpness be improved? Attached Thumbnails

June 13th, 2008, 09:41 PM	#3
Robert Young Trustee Join Date: Mar 2005 Location: Coronado Island Posts: 1,472	In Adam Wilt's review of the EX, he speaks very highly of the sharpness and overall quality of the Fujinon lens. I believe he says that there is no other lens in this price range that can touch it. With 1/2 inch chips, low f stop, and any significant level of zoom/telephoto, the EX will have significant shallowing of the DOF, so focusing is critical and many people feel that auto focus will not do the job adequately. You should be able to get a really sharp image from the EX. __________________ Bob

June 14th, 2008, 10:04 AM	#4
Paul Newman Major Player Join Date: Nov 2007 Location: Agua Blanca Ibiza Posts: 305	Please forgive me if I'm totally off beam here but, surely, a camera with 1920x1080 native chips? if you want sharp, shoot at 1920x1080 - pixel to pixel, no down conversion. Results I've viewed from 1280x720 material from my EX don't look great compared to the native HQ files at full rez. (viewed on HD tube, real, glass, monitor ) Just my 3 euro's worth. Paul __________________ Another Sunny Day in Ibiza

June 14th, 2008, 10:51 PM	#6
Dennis Robinson Major Player Join Date: Mar 2004 Location: Perth, Australia Posts: 250	Hi Gabriel, I dont think these are sharp pictures at all. In fact they are far from what I get from my JVC111 and I know the EX1 can do a better job. I am keen to learn what the others have to say about getting a sharper picture, re. iris etc __________________ Dennis Robinson G5, , 30 inch display, FCP6 Studio 2, JVC-GYHD111

June 15th, 2008, 02:32 AM	#7
Mathieu Ghekiere Inner Circle Join Date: Jun 2004 Location: Belgium Posts: 2,195	All four frames were shot outside... did you shoot with an ND filter on? Maybe you have the famous back-focus problem... PS: I don't think those frames are that bad. __________________ http://productionsofthe3rdkind.com http://pr3k.com

June 13th, 2008, 07:49 PM	#2
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	You'll want to avoid running wide open iris at full telephoto. Douglas is completely right about F2 to F4 because most lenses hit their 'sweet spot' about 2 stops down from wide open. -gb-

June 15th, 2008, 03:13 AM	#8
Robert Young Trustee Join Date: Mar 2005 Location: Coronado Island Posts: 1,472	some of the problem looks like DOF issues to me. For example: the river/forrest frame- the shrubbery in the right lower foreground appears to be sharp, and the remaining elements at different distances are out of focus. My experience is that if you are zoomed out much, you will get shallowing of DOF below f 4.0. So the focal plane must be set deliberately and serve a compositional purpose, otherwise you should move to a higher f stop to bring more of the image into tight focus. For me, it is not always easy to see all of this in the LCD, so I use peaking and the DOF indicator to help me understand what I am doing, and help make me think more carefully about what I should be wanting to do with a particular shot. To avoid DOF issues with the EX, you need to shoot wide, or shoot f8. On the other hand, shallow DOF is a brilliant tool that the EX offers, but seems a bit of a trick to gain mastery of. __________________ Bob

June 25th, 2008, 11:27 AM	#9
Sverker Hahn Regular Crew Join Date: Jun 2008 Location: Stockholm, Sweden Posts: 157	At full telephoto, this lens is not performing well at lower f-stops. After getting some unusable shots I performed a simple check at different apertures. Not until f=8 the resolution is acceptable in edges of the picture. f=11 - 16 is not as bad as f=1.9 - 5.6. So from now on, I will use only f=8 with full telephoto. At other focal lengths - I will check my lens some day soon ... Sverker

June 25th, 2008, 12:01 PM	#11
Dean Sensui Inner Circle Join Date: Oct 2001 Location: Honolulu, HI Posts: 2,054	In my experience f16 is awful. Probably due to diffraction. __________________ Dean Sensui Exec Producer, Hawaii Goes Fishing

June 25th, 2008, 01:19 PM	#12
Tom Roper Trustee Join Date: Jun 2004 Location: Denver, Colorado Posts: 1,891	I think this was shot with f2.8-3.4, 1/48th ND2, fully zoomed It's fairly sharp at the center, but a shallow DOF. Attached Thumbnails

June 25th, 2008, 03:17 PM	#13
Sverker Hahn Regular Crew Join Date: Jun 2008 Location: Stockholm, Sweden Posts: 157	Resolution might differ between cameras (?). Everybody should make their own series of tests, really. Most lenses are best at f=5.6 - 8 for what I know. And all lenses will perform worse at f=11 - 16 because of diffraction.