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Stephen L. Noe February 27th, 2006 03:10 PM

Quote:

Originally Posted by Tony Goodman
Stephen

Do even the best lenses produce CA if the shot is overexposed?

Tony

I have to defer this question over to the lens gurus of the forum. My initial reaction is no. Overexposing will cause blooming but not necessarily CA. From the input above both Tim and Charles have had their hands on the 13x lens and can be a better resource for it's CA performance. As far as the other camera's in the same price range I've seen CA on every one of them (JVC, Sony, Canon and Pan).

Tony Goodman February 27th, 2006 03:14 PM

Quote:

Originally Posted by Tim Dashwood
There is no perfect lens. Even Flourite lenses will have some CA, but will be less than non-flourite glass.

Even the 13x3.5 lens has CA. I compared CA between the lenses (results with frame grabs will be forthcoming) but it isn't as bad.

On either lens, if you open the iris up all the way you will get a purple to green gradation, top to bottom, over the whole image. We've seen this before from some people, but I've finally identified it as CA and not an electronic problem.

Tim

I notice that if I overexpose clouds they can turn a pinky magenta colour is this CA?


Tony

Tim Dashwood February 27th, 2006 03:20 PM

Quote:

Originally Posted by Tony Goodman
Tim

I notice that if I overexpose clouds they can turn a pinky magenta colour is this CA?


Tony

Probably, but it isn't about overexposing, it is about the aperature setting. For example, maybe your correct exposure for the clouds is 1/100th shutter, ND2, @ F2 and you are getting pink fringing. Try setting an equal exposure of F2.8 and 1/48th shutter and see if you still get the fringing.
Then try F4 @ 1/24th shutter and check again. The resultant exposure will be the same in all cases, but the CA characteristics should change.

If it starts to go away when you close down, then it is probably CA. Be careful not to close down more than F5.6 on a 1/3" lens or you might experience diffraction.

Tony Goodman February 27th, 2006 04:05 PM

Thanks Tim

I'll try that tomorrow, not many chances right now where I am (it's dark) but I KNOW there WILL be clouds tomorrow! There always is here!

Tony

Marc Colemont February 27th, 2006 04:27 PM

Quote:

Originally Posted by Tony Goodman
Thanks Tim

I'll try that tomorrow, not many chances right now where I am (it's dark) but I KNOW there WILL be clouds tomorrow! There always is here!

Tony

So now I finally know were all these clouds keep coming from towards Belgium...

Stephen L. Noe February 27th, 2006 07:24 PM

Another thing I've tried is rack focus with the macro ring. No breathing whatsoever. It's a tool worth a try. Does the director want every scene in the movie to be shallow DOF or certain scenes?

Efrain Gomez February 28th, 2006 02:32 AM

macro
 
Mr. Noe,
only for two scenes.
i'm gonna test the macro ring... what sort of results have you gotten using the macro ring?

:: efrain ::

Tony Goodman February 28th, 2006 12:10 PM

Quote:

Originally Posted by Efrain Gomez
Mr. Noe,
only for two scenes.
i'm gonna test the macro ring... what sort of results have you gotten using the macro ring?

:: efrain ::

Efrain

No need to go down that 'difficult' route, read what Charles and Tip are telling you, telephoto is the way to go.

I have done some tests and as long as you can set from wide open to just under F4 you can get a decent rack.


Tony

BTW. Tim, 'nothing but blue skies all the way' today!!

Jim Giberti February 28th, 2006 05:28 PM

Quote:

Originally Posted by Tim Dashwood
Here's my measured Field Of View comparison between the 13x3.5 @ 3.5mm and the 16x Stock lens @ 5.5mm and 4.5mm (with 0.82 Wide Adapter.)

http://timdashwood.com/.Public/13xvs16xFOV.jpg

Just one more reason to rent this lens for dramatic work, especially in cars.


Great info so far Tim and thanks.
Do we have a street price on te 13x yet?

Tim Dashwood March 6th, 2006 10:14 AM

Quote:

Originally Posted by Jim Giberti
Great info so far Tim and thanks.
Do we have a street price on te 13x yet?

I think $13,900 in Canada. I'm not sure about the US price.

Ian E. Pearson March 6th, 2006 12:32 PM

B&H is listing it for $8999.95. It says accepting orders.

Chris Basmas March 6th, 2006 01:02 PM

No way i'd spend that for a first gen lowly 1/3" cam
Maybe when 1/2" comes around..

Steven Thomas March 6th, 2006 01:21 PM

Quote:

Originally Posted by Chris Basmas
No way i'd spend that for a first gen lowly 1/3" cam
Maybe when 1/2" comes around..

I understand that concern.
Now if JVC allows this lens to be compatible with future 1/3" to 2/3" technology, that's a different story.

Earl Thurston March 6th, 2006 01:23 PM

Quote:

Originally Posted by Jim Giberti
Do we have a street price on te 13x yet?

CineQuip White here in Burnaby, British Columbia has it for $11,500.

Tim Dashwood March 6th, 2006 07:31 PM

Quote:

Originally Posted by Earl Thurston
CineQuip White here in Burnaby, British Columbia has it for $11,500.

That must be the Canadian price then. It is more in line with B & H's US price. I had quoted the original MSRP.


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