Edge to Edge Sharpness on LE

T

Tim Naylor

Veteran
Anyone out there test the LE's edge to edge sharpness, especially with wide lenses? I had a big problem with this on my last shoot with my 35mm and 24mm. Not sure if it's my lenses or adaptor.

Love to hear from others.

Testing this Sunday.
 
Tim Naylor said:
Anyone out there test the LE's edge to edge sharpness, especially with wide lenses? I had a big problem with this on my last shoot with my 35mm and 24mm. Not sure if it's my lenses or adaptor.

Love to hear from others.

Testing this Sunday.
Click to expand...

no vignetting with 17mm here. How far are you zoomed in on the gg? Your FOV has been adjusted for 35mm? I don't get vignetting when Zoomed in to 27.3 and beyond.
 
I think Tim is referring to edge sharpness, not vignetting per se. In my experience with the Lex any issues I've had with edge softness are attributable to the sensor offset. If I zoom in a bit more past the edge of the image circle it improves significantly. I'm expecting our friends at Letus will have a remedy shortly.

Obviously this doesn't account for the issues of individual lenses. Tim, what stops are you shooting at when you notice the edge softness? Many wide still lenses only sharpen up across the entire frame around 5.6 - 8. Wide open I'd expect at least some noticeable falloff. Any chance this is the case at least partially?
 
it doesn't really matter if they fix the offset to be honest. You should be zoomed in well past the edges of the ground glass on all sides if youre emulating a 35mm DOf and/or Fov.

If youre just shooting with the widest you can get you can still zoom in a hair to correct for lends falloff and offset incorrection with no realworld consequences.
 
Tim, I haven't been scientific in my testing yet on this and haven't compared adapters but I have definitely noticed with the Letus ( and probably all the adapters) that the sharpest point of focus for the center on the HVX is not the same for the corners. I actually have wanted to take the time to run tests.

Its clear that you have to choose whether you want to optimize for the center, the corners or pick a compromise.On the near end you get the center and as you focus further away you get to the corners. If you just set your focus looking only at the center you could end up with very soft corners.

I noticed this last week on my 80-200 Nikkor so its not neccessarily a wide angle thing though that could I guess make it worse. It also doesn't seem to be connected to the offset problem.

Are you using a blown up of a focus chart when you set-up? That makes it all very obvious.

It seemed more noticable to me the other day on the Letus, but it could be that i finally pickup up a sharp Nikkor zoom that showed the difference more and i happened to see it on the Letus instead of another.

Does this sound like what you are talking about?

Lenny Levy
 
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I found some more scientific tests by Ryan Walters.
www.timnaylor.com/edgetoedge

It's depressing. Everything I suspected. The edge to edge on the LE is not ready for prime time. I don't think it's his 50mm lens either. As I never experience that much fall off with my Nikon 50mm in still format, even wide open. It's more noticeable on wide lenses because we tend to compose more for the corners than on a long lens.

I didn't notice this at all on my LE vs SG tests, but I was also shooting with just long lenses (85mm and up).

I was having this edge issue on my last shoot and tested it on the spot at higher stops (2.8, 4.0, 5.6) and it's still there.

As I don't shoot portraiture, this is a serious compromise. It's very much as Lenni describes. I find it unacceptably soft on the edges (a bit more so on the left). Like most DP's, I stage for the left and right all the time, not just the center. This failing, won't do. Look for my LE in the marketplace. This really sucks and needs to be addressed.
 
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Tim, you have the SGpro right? how does that compare? there is a verry cool lens test by Matty G in the footage section on Waynes website, but he tests more for center sharpness. what do you think?
 
jenningsp said:
Tim, you have the SGpro right? how does that compare? there is a verry cool lens test by Matty G in the footage section on Waynes website, but he tests more for center sharpness. what do you think?
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Keeping the SG. It's non-flip mode has much better edge to edge. Was never an issue. Will be testing Timur's SG Flip to see if it has any effect on the edge to edge amongst other things within a week or so. Must admit, I'm crestfallen as I fell in love with the LE's light loss and center sharpness. There had to be a catch.
 
once i get the corrective Condenser for the SG, we will have a fully functional flip unit.
 
TimurCivan said:
once i get the corrective Condenser for the SG, we will have a fully functional flip unit.
Click to expand...

what is this corrective condenser?

is it something to do with the alignment issue some people have with the letus EX and that extending to the flip unit?
 
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Actually? I think I just reached a new level of DVXuserism: I don't care if people don't want to listen, anymore. Last word is: You aren't zoomed in far enough.
 
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Tim, have you seen this article called "Now that’s a nice piece of Glass!"at Ryan's site? It compares Nikon and Zeiss 50mms along with a Red zoom set to 50mm, and appears to suggest that a considerable amount of the difference seen in the two charts you mentioned (bare HVX vs HVX/LEX/Nikon 50mm) is due to the Nikon lens he used. The Zeiss apparently is much better.

On the other hand, if you find the SG to be far superior with the same lens then it's a different kettle of fish...

Your findings and conclusions are not good news - I ordered a LEX a couple of weeks ago. Haven't received it yet.

Hmm...
 
Tim, could you post a few grabs that show this issue? It might also be that a slight GG misalignment is to blame. When I first got my LE I had to adjust the GG to reach infinity on my Lomos. I bought a micro caliper to ensure my GG is perfectly flat to the imaging plane. If you're getting an uneven plane of focus this may well be an issue you can address.
 
guys guys. dont be worried about what your ordering. Notice how when someone brings this up with scientific evidence, everyone gets distraught. This unit has been sold and used by hundreds, footage has been thrown online, and people have fallen in love with it. The fact that very few people have even noticed what Tim is explaining means that you need not worry just because you have learned a new piece of information. the adapter is still phenomenal and you should not consider in the least replacing it because it has a slightly soft edge, according to the findings.

For those who this is truly a concern, then i am sure its valid, but for those who have one on order, i wouldnt worry too much. Because the fact is, you never noticed this in the first place.
 
well i havent noticed this edge softness that you guys have seen. Maybe, as you say, it is your unit, but i've shot two projects using this thing and the "edge softness" has never been distracting.

Timur, this is not directed towards you, or others who are in the market for an Industry quality adapter, but more so for the indy filmmakers like myself. Stop worrying about getting the best of everything and work with what you have. Some focus so much on their equipment and not enough on their craft, or get carried away with needing the best of everything that they forget what the point of having this stuff is really for. The fact is, everyone who has ordered from Letus is not ordering blind, so they have seen footage for themselves that sold to them the unit. But now that someone has announced a flaw with the unit, suddenly people will start doubting......

I have shot several paid gigs with this adapter and no one has had any complaints. Also, have two films coming out ( in french ) that have hopes of doing the film fest tour.

Just go and shoot people!
 
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