CurtPalme.com Home Theater Forum

[the_maniac]

Hello,

I have to buy binoculars, because i have no remote for my barco and focusing is very hard if you sit right next to the projector 4m away from the screen.

but which binoculars do focus on short distance ?

best regards

[Nashou66]

Iv been wanting some too, but Monaculars would work best.

Click on Pic




Athanasios

[Zebu Fellenz]

I have some very old opera glasses that focus perfectly in a short distance.

Maybe I can find a name on them that will lead to a modern equivalent, worth a shot.

Erik

[jkruger]

Do yourself a big favor and buy a remote.

[ecrabb]

Jkruger is right on.

I've tried binocs... It works, but it's SO much easier to just walk up to the screen. It's a pain fiddledefarting around switching between binocs, looking at controls, missing the part of the screen that you're adjusting because you're only seeing a tiny portion of the screen... Get a remote and do rough convergence from the comfort of your chair, and do fine convergence standing at the screen. If it looks good at the screen, it will look utterly perfect from the seat.

My .02.

SC

[Tom.W]

[Nashou66]

yes a remote is great for just focusing and you get right up to the screen, But what do you do when your doing the astig magnet? A monocular is needed.
or you can do what TSE did :

Poor man's Microvision or Focus for the Blind

its really cool, he used a video camera and an oscilloscope !!!

repose of what he did: TSE's Words

With a video camera and an oscilloscope one can optimise focus while watching the scope display even if the screen is not visible from the projector or if you are having trouble seeing the screen well from the projector location. In any case you can have the scope right next to the projector and watch it's display up close. Project a one or two pixel on, one or two pixel off pattern and focus the camera on the screen. Maximize the signal amplitude on the scope and you have the best posible focus. I think this is how autofocus on digital cameras works. Largest peak to peak is best focus.






You can use this technique for convergence, also. This is how it looks on the scope when misconverged




Move one color toward the other until the peaks become one and maximize amplitude. Convergence as perfect as possible.




You would connect the camera's video output to the scope. Set scope to view one video line (10uS/div) to look at vertical lines and the scope to view one field (2mS/div) to look at horizontal lines.

.....the technique used by these guys.

http://www.microvsn.com/

It is very helpful when dealing with very high resolutions that are hard to see from the projector. One can dial in the lens in seconds, perfectly. Optimise electrical focus. Especially good when the MTF is down in the 10-15% range.


I think the whole thing is pretty cool and I always forget to give it a try.
except for the convergence thats just crazy , you'd have to move the camera to each location!!
Microvsn has a automated rail system that they have there camera connected to as it moves around the screen(smaller displays) I wonder if they ever made a rail system for large displays?

Athanasios

[AFryia]

[jkruger]

I have some antique british navy binocs that are 4x and can focus close. They work very well.

[Kiev Savoie]

[Nashou66]

[Mark_A_W]

Binoculars suck.

Use a video camera and a TV/Monitor up at the projector.

[Ile]

I was looking cheap binoculars few weeks ago to test with astig and optical focus adjustments.

monocular 0,4 m
http://www.optik-pro.de/vanguard-monokular-dm-6x25/p,15573

binoculars 4 m
http://www.astroshop.eu/celestron-binoculars-outland-8x25/p,7803
http://www.astroshop.eu/celestron-binoculars-outland-10x25/p,7804
http://www.astroshop.eu/eschenbach-binoculars-magno-xf-10x25/p,1873

Then I found these cheap ones locally
http://www.biltema.fi/osteri/osteri.cgi?sivu=skriptisivut/index_kauppa.htm&linkki=45620.htm&tuote=45620&ryhmaid=
focus 3.0 m and when modded to monocular even closer, maybe 2,5 m.

[richardc]

Hi Guys
I was just wondering about focus with a light meter.
When I was working in the NewsPaper Industry, I worked on Photo Typesetters of various kinds crt laser etc.
The way we would focus a 10" crt was to place a light meter directly on the surface of the crt contrast down slightly so there was no bloom and the perfect focus was when the light meter had its lowest reading, either side of focus used more phosphor so a higher reading.
Now this is only for crt electronic focus not lens focus.
Now we cant put the light meter on our crt's but we can use the light meter as if we were calibrating white balance etc.
Do you guys have any thoughts on this.
Myself I have a G90, and are very pleased but we are always looking for the best image are we not.
Regards
Richard

[Kiev Savoie]

[Spanky Ham]

Kiev,
Not sure what you are asking. There are plenty of uses for a scope and Nash does use it for scoping boards and the like. In this instance, he was just expanding the uses of his scope.

If you are looking to buy a scope, then do a search on Tinman's posts.


Richard,
I am confused by what you are talking about. With Scott's method, you should be able to get the best focus possible. I am not sure how many people have tried it, but I did play with the Microvision system and it works quickly and accurately.

Maniac,
I agree with getting a remote. I would also enlist a helper. The younger the better with good vision.

[wallace123456]

For initial astig ajustments, why not look into the lens using a pair of sunglasses? It does a pretty damn good job.

wallace

[picree]

[the_maniac]

i'll try this monocular now:

http://www.dealextreme.com/details.dx/sku.3903

i think it's the cheapest you can get