[optacon-l] Re: Reading LCD monitor with the Optacon

  • From: Nancy Shackelford <ladym74731@xxxxxxxxxxxxxxxx>
  • To: <optacon-l@xxxxxxxxxxxxx>
  • Date: Mon, 13 Feb 2012 22:03:27 -0600

OK, I should've read this message before I replied... My Bad!!

Nance


Nancy Shackelford
-----  Please check out my store...Something for everyone!
www.nk-shouseofstuff.biz
----- Original Message ----- 
From: "H & C Arnold" <4carolyna@xxxxxxxxxxxxxx>
To: <optacon-l@xxxxxxxxxxxxx>
Sent: Monday, February 13, 2012 5:54 PM
Subject: [optacon-l] Re: Reading LCD monitor with the Optacon


> Well, Nancy, it's me again. I went into Alt T, not in a message, but 
> outside
> the list of them in a box. I arrowed up once until Options. When there, 
> you
> tab across the categories, and hit Control Tab for a new Tab; the first is
> General. I think about the fourth Control Tab took me to Font.
>
> In God We Trust,
>
> Carolyn
> ----- Original Message ----- 
> From: "Nancy Shackelford" <ladym74731@xxxxxxxxxxxxxxxx>
> To: <optacon-l@xxxxxxxxxxxxx>
> Sent: Monday, February 13, 2012 12:01 PM
> Subject: [optacon-l] Re: Reading LCD monitor with the Optacon
>
>
> I shall try this. Thanks.
>
> Nance
>
>
> Nancy Shackelford
> -----  Please check out my store...Something for everyone!
> www.nk-shouseofstuff.biz
> ----- Original Message ----- 
> From: "Mary Emerson" <maryemerson@xxxxxxxxxxxxx>
> To: <optacon-l@xxxxxxxxxxxxx>
> Sent: Monday, February 13, 2012 8:21 AM
> Subject: [optacon-l] Re: Reading LCD monitor with the Optacon
>
>
>> Nancy and list,
>>
>> Maybe you need to adjust the brightness setting on the CRT display
>> itself; turn down brightness. Sometimes low brightness and high contrast
>> work; sometimes low contrast and high brightness work. Also, there are
>> various ways to adjust the CRT lens itself; try unscrewing the top of
>> the lens to make it longer, instead of screwing it all the way down into
>> the lens barrel. Remember, TSI developed at least two types of CRT
>> lenses, one for CRT screens with larger print, and another for CRTs with
>> smaller print.
>>
>> Below, I'm adding the instructions that were included with the CRT lens
>> for larger print CRTs. If you have an R1D or R1C optacon, the CRT lens
>> was supposed to work in inverse mode. If you have an optacon 2, adjust
>> the mode slide switch either in the lowest or highest position; the
>> middle position is normal, if I recall correctly, and not often used
>> with a CRT lens. If inverse won't work, use normal mode; Windows often
>> has dark colors on a light screen.
>>
>> Here, starting in the next paragraph, are the instructions. Maybe this
>> information will help somebody else on the list, too.
>>
>> TELESENSORY SYSTEMS, INC.
>>
>> 3408 Hillview Avenue
>>
>> P.O. Box 10099
>>
>> Palo Alto, California 94304
>>
>> Telephone 415/493-2626 Telex 348352
>>
>> OPERATING INSTRUCTIONS FOR CRT LENS’* MODULE F1A
>>
>> INTRODUCTION
>>
>> The CRT Lens Module F1A is an Optacon accessory that may be attached to
>> the retina of
>> a Model R1C/D Optacon to read some Cathode ray Tube terminals. There are
>> numerous
>> variations in CRT’s including those which are supposedly identical,
>> which mean that
>> one’s own Optacon, the F1A CRT Lens Module, and the specific CRT in
>> question must
>> be evaluated together to determine if an effective reading system can be
>> achieved.
>>
>> Although the CRT Lens Module is designed to read characters 1/8 to
>> 1/4 inch (3 to 6 mm) tall, there are significant variables which prevent
>> TSI from
>> consistently predicting which CRT’s are readable. These include the
>> brightness and
>> contrast of the CRT display, the focus adjustment of the CRT, and
>> presence of a dust
>> cover with its underlying CRT tube curvature, extraneous light from the
>> surrounding
>> room, the refresh rate of the CRT, and the ratio of character height to
>> width.
>>
>> FEATURES OF F1A ..’-. - ..--.
>>
>> The bayonet sleeve which accepts the Optacon retina is on the back side
>> of the F1A at the
>> end closest to the user and furthest from the CRT screen during use. The
>> front end of the
>> F1A contains three small nylon ball bearings which are positioned
>> directly against the
>> CRT ^ screen during use. The features below are described in a sequence
>> from back to
>> front.
>>
>> Bayonet sleeve - accepts the Optacon retina which is inserted with a
>> push/twist action.
>>
>> Zoom lens magnification adjustment - The zoom lens adjustment ring is at
>> the back of the
>> F1A barrel, just before the barrel makes a right angle turn to the
>> bayonet sleeve. The ring
>> has a larger diameter than the barrel. It slides forward and backward
>> approximately 1/4
>> inch (6 mm) with the forward position providing the greatest
>> magnification. The ring can
>> be locked into position from its ”free-sliding” position by twisting it”
>> either clockwise or
>> counter-clockwise relative to to the barrel.
>>
>> Focus adjustment - Focus is adjusted by varying the length of the
>> barrel. About 3/4
>> inch (19 mm) forward from the zoom ring are two smaller knurled rings
>> having the same
>> diameter as the barrel. The forward ring is attached to the front half
>> of the barrel.
>> Turning it adjusts barrel length. The second ring (toward the back) is a
>> lock ring. A flat
>> side on the circumference of the barrel just forward of the two
>> focus adjustment rings provides a tactile monitor of the number of turns
>> made while
>> adjusting barrel length. .^Eleven complete turns will adjust the barrel
>> from minimum to
>> maximum length. ^ ’
>>
>> Light shield - The two inch (51 mm) diameter disk near the front of the
>> F1A is designed
>> to shield the CRT from extraneous light. In some situations, this shield
>> may be
>> unnecessary. It can be unscrewed from the barrel and removed after
>> separating the barrel
>> in two by completely unscrewing the front ^ section beyond its maximum
>> extension.
>>
>> Nylon ball bearings - Provide smooth, low-friction movement of the F1A
>> across both
>> glass screens and protective dust covers.
>>
>> SET-UP PROCEDURES
>>
>> Preliminaries:
>>
>> The sighted CRT user will generally prefer a very strong contrast
>> between the characters
>> and the background. This is usually not ideal for the Optacon. The
>> Optacon generally
>> works best when the CRT is very bright, in which case the contrast may
>> be low. In other
>> words, both the characters and the background are usually bright when
>> CRT adjustments
>> are optimum for Optacon reading. Frequently the best CRT brightness
>> and/or contrast
>> settings will result in the appearance of retrace lines on the screen.
>>
>> Preliminary to evaluating the F1A, one could ask a sighted assistant to
>> adjust the CRT
>> brightness and/or contrast controls (if present) to yield characters and
>> background as
>> bright as possible without significantly distorting character focus.
>>
>> Next, use the chart below to make an initial focus (barrel-length)
>> adjustment. This
>> adjustment will be based upon two factors: (1) F1A’s are
>> factory-adjusted at TSI to
>> various internal lens settings, and (2) CRT’s come with or without cover
>> screens.
>>
>> NOTE: For best results with a CRT with cover screen, the screen should
>> be removed. If
>> the screen is not removed, you may not be able to read some parameter
>> information.
>>
>> CRT Without Cover CRT With Cover ’., Screen ’ Screen’
>>
>> F1A Lens Setting No. 4 9 complete turns 9 complete turns (reads larger
>> print)
>> from minimum. - from ’minimum
>>
>> F1A Lens Setting No. 7 4 complete turns 1 complete turn^’ (reads smaller
>> print)
>> from minimum from minimum
>>
>> Remove the standard lens module from the Op’tacon retina module and set
>> it aside in a
>> safe place. ,
>>
>> Adjust the zoom ring to minimum magnification by unlocking it, sliding
>> it back toward
>> the bayonet sleeve as far as possible, and relocking it.
>>
>> Now, hold the F1A against the CRT screen. If your Optacon is designed
>> for left index
>> finger reading, turn the F1A until the bayonet sleeve (which accepts the
>> retina) points left.
>> (If your Optacon is designed for right index finger reading, the bayonet
>> sleeve should
>> point right.) Holding the F1A this way, insert the retina module into
>> the F1A bayonet
>> sleeve so that the camera cord emerges from the 12 o’clock position.
>>
>> CRT Light Adjustments:
>>
>> The following procedures are designed to determine whether the CRT emits
>> enough light
>> for the Optacon to operate properly. ’”
>>
>> 1. Both the CRT and the Optacon should be on, with the
>> Optacon’s normal/invert switch in the invert position.
>>
>> 2. Aim the F1A at a blank screen or blank portion of the dis-
>> play previously adjusted by a sighted assistant.
>>
>> 3. Turn the Optacon’s threshold counterclockwise until the array
>> ”blooms”. (Namely, all
>> of the pins are vibrating.) Then back off by turning the threshold
>> clockwise until the
>> bloom just disappears.
>>
>> 4. Display a line of ”L’s”across the screen.
>>
>> 5. Leaving the Optacon threshold at the setting in Step 3, scan the
>> ”L’s”. If the Optacon
>> responds, proceed with
>> F1A focus adjustments in the next section . If the Optacon does not
>> respond, increase
>> CRT contrast and repeat steps
>> 2-5.” If the Optacon still does not react to print with any of the CRT
>> contrast adjustments
>> you have made, the F1A you are using is probably not receiving enough
>> light from your
>> CRT’s screen and probably will not work with your equipment. Try
>> evaluating an F1A
>> with a different factory-adjusted lens setting (if you have one
>> available), starting again with ”Preliminaries”.
>>
>> Note: If the ”L’s” appear upside down, remove the retina module from the
>> F1A, rotate it
>> 180° and replace it.
>>
>> F1A Focus Adjustments: ’
>>
>> Ignore image size and leave magnification at a minimum with the zoom
>> ring all
>> the way back (toward you) . Try to improve focus by using various barrel
>> lengths, adjusting Optacon threshold after each barrel length adjustment
>> to
>> determine if the image is becoming clearer. Try to find the barrel length
>> adjustment which will provide the best average focus for characters
>> appearing in
>> both the corners and the center of the portion of the CRT screen that
>> you will
>> want to read.
>>
>> Magnification Adjustment: .
>>
>> Using the zoom ring and Optacon’s threshold adjustment, adjust
>> magnification.
>> When the magnification is adjusted to provide the correct image size,
>> the focus
>> may require readjustment, especially if your F1A has lens setting Number
>> 4. ”
>>
>> Improving CRT Light Adjustments:
>>
>> Assuming that previous adjustments were properly made, the F1A should
>> require
>> no further focus or magnification adjustments. Next, you want to 
>> determine
>> whether any additional adjustments to the CRT’s intensity and/or
>> contrast controls
>> result in clearer images for the Optacon. . -..- , -,.
>>
>> Before attempting to improve the CRT’s light adjustments, note the ;
>> Optacon’s
>> threshold setting and ask a sighted assistant to note the starting point
>> CRT intensity
>> and/or contrast settings. Now, without adjusting the F1A, determine
>> whether
>> variations in the Optacon threshold adjustments and the CRT intensity
>> and contrast
>> adjustments provide improved images. If not, return to the settings in
>> use at the
>> beginning of this section. Make note of these settings so that next time
>> you use
>> this CRT, you will have some way of quickly making the proper settings.
>>
>> The above instructions assume that the CRT has brightness and contrast
>> controls.
>> Not all CRT’s do. Some have a single brightness control which
>> simultaneously
>> adjusts intensity and ’contrast. Others have no ” external controls. If
>> you cannot
>> make the exact adjustment suggested, do the best you can within the
>> limitations of
>> your system.
>>
>> You may notice a beat frequency or periodic pulsation in your Optacon’s
>> array
>> when reading the CRT screen. This is due to the fact that some CRT 
>> screens
>> renew their images at a different rate than the Optacon views them. The
>> Optacon
>> camera’s scan rate has been adjusted to the average refresh rate of the
>> most
>> popular CRT’s. This may not be an | exact synchronization with your CRT.
>> This
>> electronic incompatibility ’ does not damage your Optacon in any way.
>>
>> Some CRT cover screens are quite flexible. As a result, you may discover
>> that a
>> character is in focus when you are applying very little pressure against
>> the screen
>> and out of focus when you apply enough pressure to bend the screen 
>> inward.
>> Performance may be improved by removing the cover screen, if it is
>> possible and
>> safe to do so.
>>
>> 3a0
>>
>> to view the list archives, go to:
>>
>> www.freelists.org/archives/optacon-l
>>
>> To unsubscribe at any time, just send a message to:
>>
>> optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the
>> quotes) in the message subject.
>>
>> Tell your friends about the list.  They can subscribe by sending a 
>> message
>> to:
>>
>> optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the
>> quotes) in the message subject.
>>
>
> to view the list archives, go to:
>
> www.freelists.org/archives/optacon-l
>
> To unsubscribe at any time, just send a message to:
>
> optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the
> quotes) in the message subject.
>
> Tell your friends about the list.  They can subscribe by sending a message
> to:
>
> optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the
> quotes) in the message subject.
>
> to view the list archives, go to:
>
> www.freelists.org/archives/optacon-l
>
> To unsubscribe at any time, just send a message to:
>
> optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the 
> quotes) in the message subject.
>
> Tell your friends about the list.  They can subscribe by sending a message 
> to:
>
> optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the 
> quotes) in the message subject.
> 

to view the list archives, go to:

www.freelists.org/archives/optacon-l 

To unsubscribe at any time, just send a message to:

optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the 
quotes) in the message subject.  

Tell your friends about the list.  They can subscribe by sending a message to:

optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the quotes) 
in the message subject.  

Other related posts: