Damaged Lens?

C

carrcs

Active member
I purchased a Kowa Inflight Prominar 1.5x anamorphic lens on Ebay a few weeks ago to use with my T2i. I finally received this lens today (it was shipped from the Netherlands), and the box was BADLY damaged. The seller didn't do a great job packaging it, and it also appears as if Miami customs carelessly inspected it and repackaged it. The lens itself had fallen to the bottom of the box and was no longer surrounded by bubble wrap when it arrived. Please advise. How can I tell if the lens was damaged? It was definitely bumped around quite a bit in there, but I see no physical damage. I shot with it and the image appears warped as if it's a fisheye, but that may be due to an error in my FCP sequence settings. I used 1920x817. Any help would be most appreciated in that this lens wasn't cheap.
 
Mind you, I did my test shots with a Sigma 30mm lens, which I realize is far too wide (major vignetting). Could this excessive width also caused the "fisheye"/warped effect?
 
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This is a still taken from the test footage. I imported this into FCP and changed the sequence settings to 1920x817 and then exported the still. Was this distortion caused by the 30mm lens or some damage to the Kowa Anamorphic Lens?
 
You're not unsqueezing your footage!

I don't know how it works in Final Cut, but try changing the vertical scale to somewhere between 50% and 66%.

The lens is fine, don't worry!
 
Thanks so much, guys. I did attempt to unsqueeze the footage. I Changed the sequence settings from 1920 x 1080 to 1920 x 817. That is what you see in the frame grab above. Doing that did "unsqueeze" the footage quite a bit, but not to the extent that it looks correct. I also tried leaving the settings at 1920 x 1080 and checking the anamorphic box in the sequence settings, but that also didn't look "unsqueezed" enough. Final Cut is the only editing program I have, so any advice would be most appreciated.
 
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hey,post original 16:9 frame grab ,dont go as wide as 35mm ,stay at 50mm.It looks normal here,most important is that glass is OK.
Virtualdub is free, you can download it and also plugin to import MOV quicktime files for it.Then you have resize filters to play,its free,its not non linear editor but its ok to edit single files.

Maybe 35mm would work if you would crop it to 2.4:1 from both sides and tried to bring anamorphic closer to front glass of your 35mm lens.
 
To me it looks like you need to rotate the lens.

Those lenses have to be oriented correctly.
Mark the top of the lens shoot something and turn the lens a quarter turn,
Mark the lens again shoot something else, and turn another quarter turn.
After 4 turns, go back to the edit bay and have a look, chose non square pixels if you have that option or anamorphic.

One of the images should look the way you want.
Set your lens on the mark that looks correct.
 
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Thanks so much, guys! Yes, I think I do need to rotate the lens. I am going to have to figure out another option for a step down ring in order to do that. The seller said the threads on the back of the Kowa were 52mm, but I think they are actually some odd size (like 54mm). The ring I was using was 52mm, but I could only thread it 1 3/4 turns. So, I didn't have the luxury of aligning the lens properly (nor did I even realize how to do this at that time). I will get another ring (probably have to get a metal worker to fabricate one) and try again with a 50mm lens. Hopefully, the lens is okay otherwise. The focus ring turns smoothly, there is no rattling and I see no damage. As for editing, I did have an anamorphic option, but it didn't unsqueeze it enough. Hopefully, rotating the lens (and not shooting with such a wide lens like the 30mm) will solve all problems. Any other things I need to check out on the lens to make sure it's not damaged? If it is, I need to contact the seller ASAP.
 
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rotating your lens wont solve any problems ,because youve got it right but its slightly tilted ,just keep it straight.
Put anamorphic in front onf 50mm ,keep it with your hand and shoot some vid,post framegrab.
There are no problems just dont let it be tilted because it would look weird like stretched even if correct unstretch ratio would be applied.
Your anamorphic is tilted left,if you wouldnt be able to rotate it more it would be tilted right ,i had this problem,just dont screw it to the max,keep it straight ,like 0.
 
Please forgive my ignorance, but I'm not sure that I understand you. You say rotating my lens won't solve any problems, but then again, it seems that you are also saying that I should rotate the anamorphic lens slightly to the right so as to ensure that the vertical distortion is a perfect "0" shape and not tilted to one side or the other. Please clarify.
 
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just look throught the rear of the Anamorphic lense with the Naked Eye and the Oval should appear horizontal making the object in view taller not wider. this is the correct orientation of the lense, if your lense is making the object wider hence the oval shape is vertical your orientaion is wrong. it should only get wider after post. but objest will look slightly tall. anothe test is shine a light . the Flare should be Horizontal not vertical .

Even though before post the item looked squeezed your actualy viewing more horizontal info
 
I said that i dont see any problems in pic you posted,its just anamorphic is tilted a bit thats all.It looks ok but 30mm is too wide,it might work with 35mm and cropped to 2.4:1 but you have to try to keep anamorphic as close to front glass of SLR lens as you can.
 
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