Lenses and the P4K

Hi everyone,

@admin Please let me know if this topic isn't appropriate.

Here is my problem:
I have purchased the Canon FD 300mm 2.8L to use with my P4K, primarily for filming the ocean.
During the test shoots I have experienced low contrast in the center of the image vs higher contrast
on the image left and right.

I told myself this is why you use a matte box.
There must be flares hitting the lens at the center, either from the water or the sand.
And the external lens hood for the 300 2.8 L isn't enough to block out unwanted light.
But then I filmed the forest just after sunset with the remaining sunlight behind me (see attachments).

Film Settings:
UHD 60fps / f5.6 / Iso200 /180° shutter / 5600K/ "Film"
Post Processing:
1. Screenshot of Video File in BM Raw Player
2. Applied the same Contrast Adjustment Layer in Photoshop to both Images


The lens looks immaculate, the coating seems to be brand new and
that for a vintage lens. The P4K's sensor is clean.
Any help is highly appreciated.
I'm not a cinematographer, I'm an editor so I'm not very familiar with the Physics of Optics,
but I'm always eager to learn.

Thank you.
Johannes

The attachment Test_FD300_Center.jpg is no longer available

Test_FD300_Righjt.jpg (875.33 KiB) Viewed 2154 times

Here are two more examples.

I forgot to mention that I have not used the drop in Polarising Filter with this lens yet.

Thank you

I'd recommend you take the lens to a lens technician to have it checked.

At least that will eliminate the lens itself as cause of any concerns.

Thank you both for your expertise on this lens issue.

I called Canon Support in Germany and they told me even if they would see an issue with this lens,
they could not take it apart as they don't have replacement parts for this type of glass any more in case
they damage the existing elements during the repair.

So now I have to see if I want to:

A return the lens
B work with a polariser filter to minimise loss of center contrast as well as spend more time in post processing
C live with this "special" look

As for option A, I bought this lens off a camera dealer in Japan, for which I have paid over 300€ on
import duty that I wouldn't get the return for. It's a tough decision to make for me personally.

I called Canon Support in Germany and they told me even if they would see an issue with this lens, they could not take it apart as they don't have replacement parts for this type of glass any more in case they damage the existing elements during the repair.

They may not have replacement parts, but a lens technician may keep spares on hand. Regardless, an inspection would eliminate the question over what's causing the problem.

I use a local technician - in Sydney - who charges AU$45 to inspect and service a lens. He's been working with Canon FD lenses since the 70's and really good at what he does. To me that's a small price to pay to know if it's behaving as expected, especially after such, what I imagine is, an expensive investment.

There are several things you can do before sending this lens off for repair which may not even be successful for numerous reasons but mainly because even if it was in the condition it left the factory it may still perform as it does now.
Take an LED torch and point it through the lens from both directions and check for any haze on the lens elements. A lens this old will have inevitably accumulated quite a bit from atmospheric pollution. This will then be a simple cleaning job for a camera tech.
What kind of adapter are you using - is it a simple mechanical one or is it a focal reducer with glass elements?
Cheap focal reducers are known to flare more and even good ones are not immune. If it's a simple mechanical adapter there is always a problem with the opening to the camera which will bounce light back onto the sensor. Manufacturers 'rib' this surface but it still highly reflective and worth covering in a self adhesive black flocking material.
Lastly check for light leaks between the lens and adapter and between the adpater and the camera body. I assume with a large lens you are not holding the weight of the lens with the camera mount but are supporting the lens? If not this may cause a gap between adapter and body and a light leak.

Thank you all for this valuable information.
I will run the haze test with an LED light source tonight, thanks for that John.

I'm currently in rural France and it looks like a camera technician won't be an option,
if I was in Berlin I would have went there immediately. The $45 on getting your FDs checked seems
to be an amazing deal Tristan, I'm sure it's amazing to have a lens technicians who knows your lenses well,
still need to find that person in Berlin.

Regarding the adapter, good point, I am using a cheap adapter from K&F Concept
https://www.amazon.de/gp/product/B00LEC ... UTF8&psc=1
Would you recommend the metabones FD adapter instead?
https://www.metabones.com/products/deta ... FD-m43-BT1

I do have the metabones FD focal reducer but this lens has also issues with connecting properly to the focal reducer. 7 times out of 10 the aperture mechanism won't work when the FR is engaged.
I am using a rail rod system with a lens support on a fluid drag head tripod.


Thanks!

The K& F adapter will be fine and there will be no advantage in using a metabones one in terms of image quality.

Good to know John.
Thanks for your input.