Canon FD 85mm 1.2 L with LEX

I dont know, maybe bad batteries + combination of 2.8 on the 20mm (the fastest it can do) is to blame. I hope there is sunlight tomorrow so I can do proper tests.

sami
 
exe said:
exactly , on the camera... on lens i think you go as far as you want, but not on the camera... if it's too bright, use camer'as ND filter, but dont close camera iris more than 5.6
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Really? This is totally opposite of what I have heard. Can someone confirm?

sami
 
I mean you would think as both the ND filter and camera iris are adjusted after the image comes through the ground glass that it doesnt make any difference which one you use to darken the image???

sami
 
the more you close down iris on a camera, the bigger depth of field you have and that's why GG structure starts to appear on image... i may not be 100% right, but just if you have lex on your hands, try...
 
I get that same pattern of the FX-1 if I close the camera iris down too much. Just leave it as wide as it will go and use the built-in ND filters, or additional ND's on the lens.
 
You shouldn't stop the 35mm lens down more than 5.6 in order to minimize the appearance of GG grain. The camera's f stop is much less important in this regard.
 
exe said:
the more you close down iris on a camera, the bigger depth of field you have and that's why GG structure starts to appear on image... i may not be 100% right, but just if you have lex on your hands, try...
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that does make sense though. two opinions, any more? I will test tomorrow if I have time and the sun is out.

sami
 
i read somewhere on letus forums but i don't remember now.. anyway it's one of two... imho it has to do with iris on camera... let me know, when you try it..
 
Essami said:
Damn!!! I tested and I can see this smudge on everything now! No matter if the LEX is on or off. Of course its worse if its off but it doesnt disappear as it used to. New batteries tested. What is going on!!

Sami
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Was that last screen grab with aperture (either camera or 35mm lens) closed (eg: f11)?
Have you tried taking still images of the same shot with and without vibrating motor on to compare?
From the last grab, looks like it is the ground glass but slightly out of focus too. Could be because aperture(s) are too closed. Or the motor is not vibrating at 'full speed' - maybe the cold conditions effected the power.

My first thought was the apertures are too dark, but again, compare stills (grabs) with and without motor on.
 
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OK, so turns out everyone is correct in some sense.

I did some tests and for a reason unknown I have had the 20mm iris closed down somewhat and that results in the smudge.

I did some test also which gives best performance recarding ND. Here's some very non professional test results.

First picture is with 20mm at f2.8, ND1 camera at f6.7 focus at infinity.
Secons pic is 20mm at f2.8, no ND and camera at f16 focus at infinity.

I will definately go with ND and camera stopped as open as possible as Exe suggested one should do.

Sami
 

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Hmmm... OK, so I think this issue is still not quite totally settled. I think I managed to get the focus correct but I think there is still some smudge on the shots. Look at this 1080p still.

Shot with 20mm at f2.8 with camera ND2 and f2-3.

What do you think?

-EDIT-
Also Im thinking Im seeing it only on the 1080 shots, the 720p shots I took indoors (on the above post) have none of the smudge...
-EDIT-

Sami
 

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dude, where is this place :) nice winter there!

i can't comment on this, but i think that it is normal, image is sharp, still, don't forget that you have a number glasses in front of your camera lens, so image will not be as clear as without adapter imho...

also try making 1080p screenshots with and without motor on lex turning, to see what's the difference...
 
Its Finland, Tampere. Very nice indeed. Only its really cold, about -10 celcius but with the wind its -25.

Here's some stills with LEX on and off. And notice that they look really good. Im thinking that maybe its so cold the Letus cant run that well? Is that plausible?

Sami
 

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i think everything is nice mate... when it's off, then u can clearly see grain.. you got cinematic look with grain, what else do you want :D

i still didn't get my LEX :( it's been 40 days since i ordered it, and they haven't even shipped it...
 
exe said:
i think everything is nice mate... when it's off, then u can clearly see grain.. you got cinematic look with grain, what else do you want :D

i still didn't get my LEX :( it's been 40 days since i ordered it, and they haven't even shipped it...
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You should get it soon. Mine shipped after 37 days (ordered Jan 3rd, just got it yesterday, one week after shipping).
 
Sami, it is quite plausible that wind chill in -10 to -25 celsius will dry out the batteries in metal housing quite fast. Here in Estonia it is only -8 plus heavy wind and I`m losing batteries really fast. Depending on HDV GOP and codec the smudge can show up. It`s worse on Sony I tend to think as as a Canon user ;). But really don`t close the iris on the SLR lens more than 4 or 5.6 and by the way your stills are looking great.

Cheers,
T
 
I got a reply from Aaron saying "The temperature shouldn't effect the motor significantly. I do know that batteries are effected by temperature but I don't know how much of a difference this would make."

And the curious thing is that im seeing the smudge only with the 20mm lens and only on some images. Not all the 20mm shots (as shown above) have it. Im only able to reproduce it by going all the way out to the lake! I couldnt get the smudge to appear with the exact same lens and camera settings while shooting from my balcony :) So weird!

Im working all weekend but I really want to find the cause for the smudge so Ill have to do some extensive testing next week.

But has anyone seen this sort of smudge in their images ever?

Thanks for all your help guys!

Sami
 
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