focus grief KP&C-350BH camera Fujinon YV5x2.7R4B-SA2L

[rory 0]

Yeah but cant get the camera to go in BW mode in the day time .. and that seems to be the mode to focus it in, im running down to the camera store now to see if they have some filters, I guess if they have ND filters dark enough ill get one of them, if not then ill see what kind of dark polarising filters they may have ..

[Cooperman 0]

You will need quite a dense ND filter combination to force the camera into monochrome.

 

If you try two polarising filters (expensive!), hold one on top of the other and look at a light source. Then rotate one and watch it get darker.

 

Individually, they're also great for cutting out windshield reflections under controlled lighting conditions, for example in underground car parks.

[Cooperman 0]

BTW, polarising filters look virtually clear, until you rotate one over the other.

[rory 0]

well they only had 1 type of lens filter .... a Tiffen circular polarizer

http://www.tiffen.com/polarizer_pics.htm

http://www.tiffen.com/displayproduct.html?tablename=filters&itemnum=52CP

 

i only got one to make sure its the right thing first, as cost $27 each .. which from the link above looks like I got a good deal I guess ill have to buy 1 more now then. It is fairly tinted though.

 

Also, i may look at triggering the Day Night cameras from the photocell being used on the Infrared Power Supplies, instead of letting the camera do it.

 

Rory

[rory 0]

ok so i tried the 2 circular polarizing filters, they didnt work, i mean it was too bright today. I ended up being there until 7pm anyway so I was there in the low light and pitch dark so took advantage of that.

 

Ended up with the Computar 5-50mm i had it focused in low light in color and BW mode, crisp, but when the IR came on it had to be focused for that, will see tomorrow if it is still in focus in the day.

 

The 5-50mm F;1.3 picks up more IR than the older Tamron f:1.4 which was on there for the past 4 or so years .. its also possible its an Iris pot issue though I really doubt it.

 

I also tried the part that sais open the Iris up using the iris pot. well even in low light, i saw nothing but white light .. kind of scared me ...

 

Though zooming into T and back focusing helped a little .. it was kind of in focus in W ,, but not exactly. Though it was close enough and could be focused from there.

 

The polarizing filters did nothing in this sun light, but hamper me from focusing .. in fact, I could only get a decent focus in low light which was around 5.45pm when it was dropping off to night, quickly. It started getting dark 5.30pm, switched to BW around 5.45pm, and was pitch black by 5.55pm. The camera itself kept switching from color to BW back and forth for 10 minutes until it was pitch dark. The Sanyo's have a manual control but you need a switch to work it.

 

So basically need to still focus the cameras here in low light, which this time of the year is 5.40-5.50pm. With IR i think the main issue is the focus shift, the new lens is f:1.3 5-50mm and the old one was f:1.4 3-12mm (set to 12mm) ... which also may be an issue and definately be an issue why you see more IR at night with the IR on. So i can get the camera to work day and night, but the IR comes on, another issue.

 

Since my retina isnt that great right now. im logging off. Though its from the sunlight , .. way too much today, no clouds anywhere ..!

 

Anyway ..

Rory

[Cooperman 0]

Somethings not quite right here rory,

 

So how exactly did you use the polarising filters?

 

Ignore what was written on the filter description page, you're not simply polarising the light in just one plane as described; you should be using both filters - the first filter polarises the light, and then when the second is rotated, it progressively blocks the rays from passing through, hence the variable ND effect. If sunlight is causing flare on the filter, then you should also consider buying a rubber screw on lens hood.

 

I'd suggest you have a play around with the two filters just indoors for now - don't even bother with a camera. If they're not going dark as you rotate them, then they're not polarising filters.

 

BTW $ 17 for a filter actually sounds very reasonable.

 

Incidentally, there's nothing to say you can't filter out the light with either ND's or polarisers, and then also add the dichroic IR filter to focus at maximum aperture at a specific fixed IR frequency.

 

If you focus shift the lens slightly off optimum for colour (low light) use, when the B/W kicks in, the increased depth of field resulting from the aperture closing slightly, should take care of your focus problem. During daylight, the small apertures (giving a larger depth of field) should provide a crisp image whether it is under visible or IR frequencies.

[rory 0]

hi coop, it would get slightly dimmer as i turned the second one ..but sun was still too bright to get a good focus.

 

i just screwed one into the other, then was twisting the one furthest from the camera. ..

 

But imagine, ontop a ladder, hot, windy, a monitor and balancing the ladder on the grass lawn, trying to hold the camera as when back focusing it moves, and hold the filter infront of the lens without it hitting each other, which it did and the filter got scratched, oh yeah, and focusing the lens .. only bush and trees to focus on also at the 50mm zoom.

 

Anyway, definately have to back focus these things at my place in the future .. then like i always did, focus at the location under low lighting.

 

I focused the BW mode with IR on and stays focused enough in the day in color ...

 

thanks

Rory

[Cooperman 0]

You could set up the filter rotation on the ground, tape them togethor, then that's one less thing to worry about when you're hanging off a ladder (been there, done that! Actually did it last week with a temporary two camera install).

 

The polarisers should give a very dark effect at maximum (90 degree) rotation. If it only looks slightly grey, then there is something not quite right with the filters. If a filter scrathed easily, then it's probably poor quality plastic. Glass is slightly more expensive, but you get what you pa ..... etc. etc.

 

Incidentally, depending on what cameras you are using, it's often easier to remove the camera to ground level to set up focus / exposure controls, and then refit it and align after you've done the main adjustments. If necessary you can use extension leads to reach the monitor at ground level, which is generally much safer than trying to use two hands for a four hand job.

[rory 0]

yep, ground level definately ..

 

in this case im going to probably switch out the lens for an IR lens so it stays in focus in low light also, but only if the client says so. It stays in great focus in the day and with IR but in very low light it is not ..then again its very dark in very low light so ..

 

Biggest thing i found with these Sanyos, is that they switch to quick when a car has its brights on, so im going to see if I can find a photocell and use the manual switchover .. ofcourse the Extreme CCTV Box cams come with Photocell switchover .. Client said money isnt a issue just wants the best, so I think time to switch the sanyos for either some all in one Extremes, or at least an Extreme box cam with IR corrected lens ..