Computar - lens needs work? where?

[Tim 0]

I bought a used Computar lens H10Z0812AMS 8 to 80mm, The auto iris works ok, the motors that operate the zoom and focus, run in both directions when I reverse the power to leads to it . But I can only focus in one spot close to the 80mm distance, almost zoomed all the way out, It will not focus in any other position. Can someone tell me whats wrong here? Or where I can send it to have it fixed, does it need calabration?

 

Thanks, Tim

Your can e-mail me if you like at midwestmeteor@earthlink.net [/b]

[rory 0]

zoom it all the way wide, back focus it, zoom it all the way in, back focus it, do this until it stays in focus all the time while zooming.

 

This 'may' help.

 

Rory

[Tim 0]

zoom it all the way wide, back focus it, zoom it all the way in, back focus it, do this until it stays in focus all the time while zooming.

 

This 'may' help.

 

Rory

 

No matter what I do with the focus when its zoomed in, it will not focus. It will only focus at 95% wide, and only there will it focus at that spot no where else

 

Thank You , Tim

[rory 0]

Did you adjust the back focus on the Camera itself?

 

What type of camera is it? Can you try it on another camera?

Are they both the same Formats? Like 1/3".

 

The lens is a 1/2" Lens from specs I found on the web, is the camera 1/2" or 1/3"?

[Tim 0]

Did you adjust the back focus on the Camera itself?

 

What type of camera is it? Can you try it on another camera?

Are they both the same Formats? Like 1/3".

 

The lens is a 1/2" Lens from specs I found on the web, is the camera 1/2" or 1/3"?

 

The camera is a Sanyo VCB 3524, I see two screws on the side of the camera, one labeled Adj lock, the other is labeled flange back. is the flange back the adjustment your talking about? This is a 1/2 lens

 

Tim

[AVCONSULTING 0]

First thing to check is if your camera is set to C or CS mount. I think that the camera you are talking about comes with a C mount adapter ring, usually a thin black or silver ring that threads into the front of the camera.

Since the lens you are using is a C mount lens you will need to make sure the ring is on the camera. If not then you won't be able to get it to focus properly even with the backfocus adjustment. If you don't have a ring then you'll have to buy one from a CCTV supplier. They cost about $8. The lens is a 1/2" format and so is the camera so there is no problem there.

I'm betting you don't have the ring on the camera.

 

Here is a link to the instruction manual if you don't have one. Note on page 8 is a picture of the C mount adapter ring you should have or need to get and on page 18 is a description on how to do backfocus adjustments.

 

http://www.directlvs.com/Camera/SanyoP/PDF/VCB-3524_mn.pdf

[Tim 0]

I think your betting right, I don't have a C mount adapter, the manual you refered me to points this out. I want to say you people here have been lots of help to me here. Rory bless your heart hope you win the lottery both of you.

THANK YOU, Tim

[rory 0]

no problem, page 18 of that manual tells you how to adjust the back focus.

 

And yes, you will need to use the C mount adaptor in this case.

 

Rory

[AVCONSULTING 0]

If I remember correctly there is a CCTV distributor in Earth, MO SES that can get you an adapter. If you have trouble finding one let me know. Are you in St. Louis?

[Tim 0]

Yes, In St Louis. I odered one from Direct low voltge supply earlier today

[AVCONSULTING 0]

That should solve your problem. I grew up in St. Louis. Still have lots of family there. What area do you live in?

[Tim 0]

I lived in Florissant for many many years, I'm now living in Southwest County. Where did you growup at? Went to Riverview High, grad in 1969

Guess I'm not just an old man, very young at heart

[AVCONSULTING 0]

I grew up in Clayton and then went to Washington U. Graduated in 1970 and then moved to Los Angeles to seek my fortune and fame. Unfortunately that never happened and I ended up in the CCTV business.

[Tim 0]

Got the C mount adapter today, it will now focus, I needed to set two switches inside the camera to get the iris to work right. You guys did a good job getting me straightened out. I have do have another question, when I point the camera to a white house outside, the picture streaks with white around the windows of the house and other object, WHY does it do that? When the sun went down there were no streaks of light.

[rory 0]

Smudges on the housing window or lens itself?

 

Clean them both and see how it looks then.

[AVCONSULTING 0]

That is a typical overload reaction on a CCD chip. You are probably talking about a vertical streak. Not much you can do about it. What happens is the individual pixel on the chip overloads and spikes.

[Tim 0]

That is a typical overload reaction on a CCD chip. You are probably talking about a vertical streak. Not much you can do about it. What happens is the individual pixel on the chip overloads and spikes.

 

Yes they are vertical streaks, it shows up when camera pointed at a bright area.

[kaysadeya 0]

Yesterday, I received a Sanyo VCB-3384 and four lenes. At first, I couldn't focus any of the lenses to save my life. Zoomed in and out, focused, cranked up and down on the flange-back adjustment, but no joy.

 

Then I removed the lens and poked on the top of the "flange-back" (the plastic rectangle that frames the chip). The flange-back popped into position and was adjustable after that. The flange-back appeared to have been forced all of the way to the back and was stuck. The camera was supposed to be "new" (bought it on Ebay). I suspect the previous owner put in a lens with too deep a mount and forced the flange-back all the way to the back.

 

Just my 2-cents on one more thing to check when you encounter focusing problems.

[rory 0]

hmmm, i have a dome i was going to send back, that used to be working great, until we moved it, its a varifocal auto iris, did everything but it would not focus right, though seems more like the iris is shot. Ill open it up one last time before I send it back to check this thing out, just in case ...thanks

 

rory