Anamorphic lens really does mess up the focus even when wide

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danstanbury

Active member
Can anyone who owns the Panasonic 16:9 adapter either confirm or deny this?

I know there have been quite a few posts which have mentioned that the anamorphic lens is not useable at extreme zoom, so this I expected, it's just impossible to focus.

However I was very dissappointed to find that even at wide angle, when I shot a printed page up close the letters could not be focussed anywhere near as sharp as without the lens. Even the squeeze mode gives a clearer image than this.

Now the lens is second hand and there are some very small specs on the inside (not sure whether dust or scratches at this stage) could this alone make so much difference? Or maybe I'm fitting the lens incorrectly but I don't think so, I've followed instructions to the letter.

Thanks for your feedback
Dan
 
I have and use the AG-LA7200 often and if you know how to focus with it (it is a very different procedure from non anamorphic situations), it works just fine at full wide.

Do you understand the nature of this type of adapter?

You need to establish two focus points (horizontal and vertical) then set the camera to the geometric mean point and then apply the correct aperture to stop down far enough to get both points into within the DOF for the zoom/focus combination that you are using.

From another thread, didn't you indicate that this adapter may not be a Panasonic device but a different aftermarket brand or did I misread that aspect?

Regardless, you really need to understand how an anamorphic adapter behaves to get good results from it.
 
hey thanks thanks getting back. No its definitely the AG LA7200, but second hand so I had concerns as to its condition. I have to confess I don't really understand the naturue of the adaptor and your advice went somewhat over my head. How do you establish a vertical as apposed to a horizontal focus? I suppose to get the mean of the 2 I just turn the dail half way between? Does this in effect mean that nothing is ever truely in focus, its just a compromise? Cheers Dan
 
OK, now that we know that it is a LA7200 we can proceed.

You should get a focus chart to start with, here is a link to one that I put up on my website for you to download:

http://www.museelectronics.com/cvp_focus_chart.pdf

Download and print out the focus chart on a good sharp printer using some decent stiff card-stock.

Now set up a test so you can learn how this works. Set up the camera on a tripod and place the focus chart a few meters away from the camera, this will be much easier if you have a good monitor attached to the camera, but if not, then use the EVF DTL function to help to find the focus points.

Next open up the aperture and zoom in so that the focus chart fills the frame. Now begin to focus on the chart. What you will notice is that there is a single point where the vertical lines are in focus and another where the horizontal lines are.

Make a notation of these two points (MF numbers from the DVX). Now find the geometric mean of these two numbers and set the camera to that focus number.

Next you need to stop the camera's lens down enough to be certain that both of these two points are within the DOF for the combination of zoom and focus that you are using. A link to a chart which establishes the maximum aperture (minimum F-stop number) that you can use is:

http://adamwilt.com/24p/7200chart.html

These are good starting points, but I find that I prefer to actually evaluate the frame at the time that I am shooting.

A trick that I find works well is to have the chart that I pointed out above attached to the back of your slate, then just have the first AC flip the slate over just before slating the take and you can grab your focus points quickly without adding much of anytime to the setup.

It isn't so much a "compromise" as it is just setting up the camera for the requirements of any anamorphic adapter.

By the way, paying £200 for an LA7200 is a great price.
 
Hi, thanks for the detailed advice. I don't have a printer here so will follow this process to the letter when I get a print out tomorrow and see how easy / practical it is for what I want to do. I bought into the dvx and equipment to make travel documentaries, not films with a crew, so I'm starting to think that the preparation required for the anomorphic lens is quite alot for someone operating quickly on their own, which might mean I'm better off sticking with 3:4 or squeeze mode, for most instances. Many thanks for all your help. Dan
 
You might find that you can mix anamorphic footage with squeeze footage (but never at the same time!) in the same time line. Anamorphic's advantage would best be used in longer shots where the resolution advantage can be used to the greatest advantage.
 
ana lens

ana lens

while using the anamorphic lens does the setting in the cam have to be set on letterbox or normal when using the ana lens.
 
May I also suggest getting a copy of Barry's book, it is invaluable in many ways, but especially for the anamorphic... "The DVX Book" by Barry Green
 
bilgami said:
while using the anamorphic lens does the setting in the cam have to be set on letterbox or normal when using the ana lens.
Click to expand...

Must be on normal. KHMuse method is of course as always the technically correct method to obtain perfect focus (I only know this correct method from reading a previous post from him - then Barrys book), but really get Barrys Book there is a chart in there that will make life much easier.

When you use the conversion chart in Barrys book do the same thing with the focus chart then use Barrys method as a trial, Ill think youll find the numbers match 99% perfect.

As I mentioned in a recent post, the hardest thing I find with the ana lense is action scenes, where the actor can slightly drift outside my wanted focul point, I try tracking them with mf, any other suggestions?
 
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