JVC GY-HD100-250 35mm Nikon-mount lens adapter comparison

Saul Martinez · May 21st, 2008, 11:34 PM

I have a Zoerk adapter and I've seen the same redflare specially when tilting with a 28mm Nikon lens. Have anybody asked to Zoerk/Mtf about this phenomenon?

Eric Gulbransen · May 22nd, 2008, 11:02 AM

Saul, I organized a few pages on this subject which follow the original adapter comparison that I linked to on page one of this thread. Mario Cater sent me some homework he did on this subject, which I put together here on page three of the test http://www.reelsense.net/HD-200/JVC-...RED_FLARE.html

I plan to have another go at this tonight. Maybe give it a whirl yourself. Hopefully you'll have better luck.

Saul Martinez · May 22nd, 2008, 12:49 PM

I have seen the link of Mario's work. Very interesting.Let us know about your new experimentation.
Thanks.

Doug Harvey · May 22nd, 2008, 03:56 PM

I tried alot of masking and shapes inside the adapter but the easiest way to get rid of the red flare is to take your camera with your nikon lens installed, make sure to use a filter or polarizer on the lens. Hook up your camera to a decent monitor or HD TV, create the conditions to get the red flare, now take a business card and begin to cover up the lens. Find the spot where the red flare disappears and this will be how much the lens has to be covered. If you go too far, you will see on the monitor the image will start getting darker. I have found that its about 1/3 of the lens that has to be covered. This works on my macro 60mm Nikon, 70-200 Sigma, 80-400 Nikon, 18-70 Nikon. What I have done is, to keep the one polarizer set up this way and just use different rings to fit the lens. The images produced with this combo sure beats out the standard lens.
Hope this helps you out until someone comes along and makes an adapter that really works in the outside world.

Doug Harvey

Gordon Hoffman · May 24th, 2008, 08:24 AM

I had a similar problem when I had an adapter built for mounting a Tokina 150 to 500 lens on a Sony camera in the mid 90's. Under certain light conditions I had a purple colour on the bottom part of the image which seemed to be light reflecting inside the lens some how that the camera doesn't like. Like Doug mentioned I found out if I moved my hand in front of the lens at a certain point I could get the purple colour to disappear. My fix was to make the objective lens smaller by putting a cover made of hard plastic with a smaller hole over the end of the lens. I lost some light but it fixed the problem. Later I mounted the same lens on a XL1 and never had the problem with the purple colour even with out the plastic cover. To me it appears that some cameras have a problem with mounting 35mm lens on them.

Gordon Hoffman

May 21st, 2008, 11:34 PM	#31
Saul Martinez Regular Crew Join Date: May 2004 Location: Guatemala, Guatemala Posts: 63	I've had the same redflare I have a Zoerk adapter and I've seen the same redflare specially when tilting with a 28mm Nikon lens. Have anybody asked to Zoerk/Mtf about this phenomenon? __________________ Saultv

May 22nd, 2008, 12:49 PM	#33
Saul Martinez Regular Crew Join Date: May 2004 Location: Guatemala, Guatemala Posts: 63	Thanks Erick I have seen the link of Mario's work. Very interesting.Let us know about your new experimentation. Thanks. __________________ Saultv

May 22nd, 2008, 03:56 PM	#34
Doug Harvey New Boot Join Date: Apr 2006 Location: Port Stanley, Canada Posts: 23	How to Get Rid of the Red Flare I tried alot of masking and shapes inside the adapter but the easiest way to get rid of the red flare is to take your camera with your nikon lens installed, make sure to use a filter or polarizer on the lens. Hook up your camera to a decent monitor or HD TV, create the conditions to get the red flare, now take a business card and begin to cover up the lens. Find the spot where the red flare disappears and this will be how much the lens has to be covered. If you go too far, you will see on the monitor the image will start getting darker. I have found that its about 1/3 of the lens that has to be covered. This works on my macro 60mm Nikon, 70-200 Sigma, 80-400 Nikon, 18-70 Nikon. What I have done is, to keep the one polarizer set up this way and just use different rings to fit the lens. The images produced with this combo sure beats out the standard lens. Hope this helps you out until someone comes along and makes an adapter that really works in the outside world. Doug Harvey

May 22nd, 2008, 11:02 AM	#32
Eric Gulbransen Major Player Join Date: Nov 2006 Location: Palo Alto, California Posts: 520	Saul, I organized a few pages on this subject which follow the original adapter comparison that I linked to on page one of this thread. Mario Cater sent me some homework he did on this subject, which I put together here on page three of the test http://www.reelsense.net/HD-200/JVC-...RED_FLARE.html I plan to have another go at this tonight. Maybe give it a whirl yourself. Hopefully you'll have better luck.

May 24th, 2008, 08:24 AM	#35
Gordon Hoffman Major Player Join Date: Dec 2005 Location: Pincher Creek, Alberta Canada Posts: 619	I had a similar problem when I had an adapter built for mounting a Tokina 150 to 500 lens on a Sony camera in the mid 90's. Under certain light conditions I had a purple colour on the bottom part of the image which seemed to be light reflecting inside the lens some how that the camera doesn't like. Like Doug mentioned I found out if I moved my hand in front of the lens at a certain point I could get the purple colour to disappear. My fix was to make the objective lens smaller by putting a cover made of hard plastic with a smaller hole over the end of the lens. I lost some light but it fixed the problem. Later I mounted the same lens on a XL1 and never had the problem with the purple colour even with out the plastic cover. To me it appears that some cameras have a problem with mounting 35mm lens on them. Gordon Hoffman