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explain a little?

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Ok for my education now, since i do not use these types of cameras yet, can you explain why and when you would use a lens with an auto iris that is dc driven or video driven and what is the difference?

 

In my cams that are sealed I know there is a little servo that seems to do the work but I set nothing or adjust nothing, so perhaps this is video driven?

 

At some point i guess i will be doing the inside of a shop/showroom and i supppose that a convential box cam will give the best shot?

 

Most of my units are 1/4 imagers. What do we gain by 1/3 imagers? Am I correct in understanding that we need more light at 1/3?

 

All my units have been dc powered and I have no problems with line lock or sync and I do not undrstand why this is a problem or is it with ac cameras?

 

I appreciate the education

 

Thanks

Larry

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All new lenses of the varifocal type are now DC driven. Video driven lenses are pretty much history. Generally they were in 2/3" or 1/2" format. Just make sure you have the switch on the camera in the DC position when using an auto iris lens. You can tell the difference by looking at the barrel of the lens. Video driven lenses have two small screw pots in the barrel which are used for adjusting the light range of the lens. DC driven lenses have no such screw pots because the adjustments are in the camera not on the lens. When using an auto iris lens make sure you turn off the camera's auto light adjustment or the lens and the camera will fight each other for control of the lighting. Unless your camera has an unusually good light range you will need to use an auto iris lens for outdoor scenes so it can properly adjust for the brightest daylight light to the lowest nighttime light. Also make sure you adjust the focus at night, or fool the camera into thinking it is dark by using dark filters in front of the lens.

 

As far as 24vac or 12vdc in line lock, that was only important when using switchers, rarely used these days. Quads, Multiplexers, DVRs, all automatically compensate for out of sync camera signals. Just make sure with either 24vac or 12vdc that you have enough current at the camera or your signal will be very weak. More problems with weak current happen with 12vdc mainly because people use low current power supplies while most 24vac power supplies are very robust.

 

These days there is almost no difference in quality between 1/3 and 1/4 inch cameras. If you use a varifocal lens then you will almost always be able to find the right focal length.

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a whole wealth of leanring in 3 paragraphs!

Some good info.

 

All new lenses of the varifocal type are now DC driven. Video driven lenses are pretty much history. Generally they were in 2/3" or 1/2" format. Just make sure you have the switch on the camera in the DC position when using an auto iris lens. You can tell the difference by looking at the barrel of the lens. Video driven lenses have two small screw pots in the barrel which are used for adjusting the light range of the lens. DC driven lenses have no such screw pots because the adjustments are in the camera not on the lens. When using an auto iris lens make sure you turn off the camera's auto light adjustment or the lens and the camera will fight each other for control of the lighting. Unless your camera has an unusually good light range you will need to use an auto iris lens for outdoor scenes so it can properly adjust for the brightest daylight light to the lowest nighttime light. Also make sure you adjust the focus at night, or fool the camera into thinking it is dark by using dark filters in front of the lens.

 

As far as 24vac or 12vdc in line lock, that was only important when using switchers, rarely used these days. Quads, Multiplexers, DVRs, all automatically compensate for out of sync camera signals. Just make sure with either 24vac or 12vdc that you have enough current at the camera or your signal will be very weak. More problems with weak current happen with 12vdc mainly because people use low current power supplies while most 24vac power supplies are very robust.

 

These days there is almost no difference in quality between 1/3 and 1/4 inch cameras. If you use a varifocal lens then you will almost always be able to find the right focal length.

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yes you get better quality with a traditional type camera, because of the better quality lens, and they normally have more settings taht can be adjusted.

 

Mini domes or bullet cameras have micro lenses or some mini varifocal, which are OK, but a full sized lens can give a better image, along with the better board in the traditional camera itself.

 

 

 

Ok for my education now, since i do not use these types of cameras yet, can you explain why and when you would use a lens with an auto iris that is dc driven or video driven and what is the difference?

 

In my cams that are sealed I know there is a little servo that seems to do the work but I set nothing or adjust nothing, so perhaps this is video driven?

 

At some point i guess i will be doing the inside of a shop/showroom and i supppose that a convential box cam will give the best shot?

 

Most of my units are 1/4 imagers. What do we gain by 1/3 imagers? Am I correct in understanding that we need more light at 1/3?

 

All my units have been dc powered and I have no problems with line lock or sync and I do not undrstand why this is a problem or is it with ac cameras?

 

I appreciate the education

 

Thanks

Larry

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Spot On Mr AV as usual..

 

One thing to mention though, you can purchase lenses for either 1/4 or 1/3" so make sure you purchse the lens that fits your CCD size... cheaper cameras may not have adjutments because the guts inside do the work, I am not really sure how, maybe AV can shed some light (pardon the punn), however my understanding is that the voltage adjustment makes for opening or closing of the Iris, you can still get a lot of video drive lenses but most are used to replace old ones as the DC is the new format.

 

Using the DC level can also be very usefull to get a correct back focus.

 

I think you will see that a lot of camera companies will shift to built in lenses as the popularity of easily installed cameras with say 2 to 10 mm lenses grows. I know that Ganz (2nd biggest camera seller in the world) has made a lot of these type of late for this reason, I even got one of their day/night dome cameras with built in 2 to 10mm lens and CS mount guts, nice peice of kit... anyone bar AV guess who is the only one that sells more than Ganz?

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Spot On Mr AV as usual..

 

One thing to mention though, you can purchase lenses for either 1/4 or 1/3" so make sure you purchse the lens that fits your CCD size... cheaper cameras may not have adjutments because the guts inside do the work, I am not really sure how, maybe AV can shed some light (pardon the punn), however my understanding is that the voltage adjustment makes for opening or closing of the Iris, you can still get a lot of video drive lenses but most are used to replace old ones as the DC is the new format.

 

Using the DC level can also be very usefull to get a correct back focus.

 

I think you will see that a lot of camera companies will shift to built in lenses as the popularity of easily installed cameras with say 2 to 10 mm lenses grows. I know that Ganz (2nd biggest camera seller in the world) has made a lot of these type of late for this reason, I even got one of their day/night dome cameras with built in 2 to 10mm lens and CS mount guts, nice peice of kit... anyone bar AV guess who is the only one that sells more than Ganz?

 

Sony?? Pano??

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Give that man a cigar!!

 

To be honest Pano is small here so I was very surprised and I had honestly no idea Ganz was so big, we just had the head office from japan visit us so I found out only now, they are starting to frustrate us a little though because each country has own office and develop own products, so I have to wait for ages for products say designed in germany, like the thermal gear, can take months and to order something they want to sell you, then they may have to get it first, so can become very time consuming excersise.

 

BTW, I am going to clear a whole bunch of old stock after I do stock take, have some older Ganz cams that would be very cheap if anyone interested?

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Thanks

 

I thought maybe Sony becasue they have the name, but ive seen Panasonic around alot, though I personally dont liek them.

 

I see they sell that Ganz Thermal camera in the US for like $8000!

 

 

Ganz US prices

http://www.spytown.com/search--by-part-number-computar-indoor-domes-with-intergrated-varifocal-lenses.html

 

 

Give that man a cigar!!

 

To be honest Pano is small here so I was very surprised and I had honestly no idea Ganz was so big, we just had the head office from japan visit us so I found out only now, they are starting to frustrate us a little though because each country has own office and develop own products, so I have to wait for ages for products say designed in germany, like the thermal gear, can take months and to order something they want to sell you, then they may have to get it first, so can become very time consuming excersise.

 

BTW, I am going to clear a whole bunch of old stock after I do stock take, have some older Ganz cams that would be very cheap if anyone interested?

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Wow, what a rip off!

 

I sell the colour daynight for the roughly the same price they sell the B/W LOL

 

your closer to Japan I guess?

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Was that Mr. Fuji who came by to visit? I'm going to see all of the Ganz guys at the ISC show in March. They used to be one of my biggest sellers when I had my distributing business. We did about 1 million a year with their products. I really like those LCH cameras with the built in vari-focal lenses. Their West Coast office is about 5 miles from my house so I have lunch with the Western Regional manager about twice a month. He said the thermal cameras are doing very well here.

 

Regarding 1/4" cameras, you can still use a 1/3" lens on them. It will work just fine, but you can't use 1/4" lenses on a 1/3" camera since there isn't enough glass in them to cover the whole chip area and you'll get a tunnel effect in the picture. Video lenses are on the way out. As you said, primarily replacements. They are much more expensive than DC lenses and really don't provide any better picture.

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No the rep that visted us was a Mr Toyota we have been buying of him for some time now, the LCH series are obsolete now, we are trying very hard to get a credit account with them so that we can hold more stock, we run out far too fast, however our Korean gear sells a lot more because of price.

 

Ganz are great, fantastic products, the only problem is that development is done in different areas so now the new exciting Day Night dome camera is manufactored in Korea which does not sound as impressive.

 

your right about the lenses, I should have been clearer, we have a bundle of 3.5 to 8mm auto iris video drive lenses that we are selling off at $50 Australian which I think is about $30 US.

 

Very hard to get rid of.

 

If you speak to Ganz there tell them we are very happy and we hope to do more business with japan if we can get credit.

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