the following description will first briefly present the general structure and operation of the hardware and software of a computer system incorporating the present invention and capable of performing image processing and display operations and of communications operations , including communications of images . the structure and operation of such a system will be well understood , as presented herein , by one of ordinary skill in the art and further details of the structure and operation of such a system are presented in u . s . patent application ser . no . 440 , 668 , filed nov . 10 , 1982 and incorporated herein by reference . the specific system selected for illustrative purposes is a wang &# 34 ; professional computer &# 34 ; available from wang laboratories , inc ., lowell , ma 01851 . having presented a context , that is , apparatus in which to practice the invention , the color to monochromatic image transformation method of the present invention will then be described in detail . the following will then describe an exemplary color image system which may be used as source of color images to be transformed by the above described data processing system . the color images and system described therein are representative of many other commonly used color image systems which may be sources of color images to a system as described above . other sources of color images , such as color graphic computer systems , may also serve as sources of color images , as may the exemplary system described in the present patent application . in the latter case , the color transformation of the present system may be used , for example , to transform a color image generated by a system when a monochromatic printer connected from the source system is used to provide a hard copy of images created therein . the color transformation of the present invention may be used in relation to videotex systems such as teletel and prestel . prestel is a public data base television type system used in the united kingdom ; prestel is a trademark of the british post office for prestel services . prestel is presently used , for example , to selectively distribute , under viewer control , information of interest to the public from a central prestel data base . the information contained in this data base may pertain , for example , to weather and stock market reports and shopping guides and entertainment guides . the information so provided is primarily in the form of color images containing both text , that is , alphanumeric characters and symbols , and graphic or pictorial elements . referring to fig1 an isometric view of the computer system is shown . system 10 includes a display 12 , a keyboard 14 and a central processing unit ( cpu ) 16 . display 12 and keyboard 14 are the primary means by which information , for example , text , is communicated between the system and a user . cpu 16 , which is connected to display 12 and keyboard 14 by cables which are not shown , includes a memory for storing programs and data and a general purpose arithmetic and logic unit ( alu ). cpu 16 may further include disc drives for storing programs and data and interfaces to peripheral devices , such as printers , disc drives and telecommunications devices . as described above , system 10 may be comprised , for example , of a &# 34 ; professional computer &# 34 ; available from wang laboratories , inc ., lowell , ma 01851 . referring to fig2 a and 2b , a block diagram of system 10 is shown . system 10 &# 39 ; s alu in cpu 16 is comprised of a main processor ( main p ) 18 and a co - processor ( co - p ) 20 . main p 18 and co - p 20 , may , for example , respectively be a 16 bit intel 8086 alu and an intel 8087 numerics processor extension . main p 18 and co - p 20 perform all arithmetic and logic operations for cpu 16 , including addressing , memory references , and control of input / output ( i / o ) operations . main p 18 and co - p 20 communicate through local bus 22 and with the remainder of cpu 16 , display 12 , keyboard 14 and all peripheral devices through address bus 24 , data bus 26 and control bus 28 . the interface between main p 18 and co - p 20 and busses 24 , 26 and 28 is through address latch 30 , data transceiver 32 and bus control 34 . referring next to cpu 16 &# 39 ; s internal control logic , associated with main pbeing provided with three spaced apart upstanding spacers 32 . in more detail , it will be seen that rear sidewall 12 is integrally joined with each of the sidewalls 16 , 18 , at smooth , rounded rear corners 34 . moreover , the wall 12 is provided with a total of five formed recesses 36 therein , respectively located directly beneath an associated connector wall 26 in the region between the tube - receiving regions 24 . attention is next directed to fig1 and 3 which depict the particular construction of front wall 14 . in this regard , it will be seen that the front wall 14 is integrally connected with the sidewalls 16 , 18 at smooth , rounded corners 38 . moreover , the front wall 14 includes a series of openings 40 therein respectively in communication and alignment with the corresponding tube - receiving regions 24 . it will be noted that four openings 40 of relatively deep configurations are provided , along with two openings 40a of somewhat shallower configuration . the openings 40 , 40a are designed to receive and accommodate the connector prongs of fluorescent tubes received within the supports , as those skilled in the art will readily appreciate . however , it will be observed that each of the recesses 40 , 40a , at the left hand margin thereof as viewed in fig1 and 2 , includes a somewhat triangularly - shaped ledge or platform 42 and a correspondingly shaped relieved zone . as explained previously , other embodiments of the support provide a different placement for the platforms 42 and relieved zones . in particular , in another embodiment of the invention , the platforms 42 and relieved zones are provided at the righthand margin of each recess 40 , 40a , as opposed to the configuration specifically depicted in fig1 . thus , and considering an interfitted stack of the tube supports , the left and righthand placement of platforms 42 would alternate in the stack so as to establish and maintain a proper spacing between individual interfitted supports . referring particularly to fig2 and 3 , it will further be seen that front wall 14 is provided with a total of five somewhat triangularly shaped , arcuate in cross section , open top , upwardly diverging recessed zones 44 . these zones are defined by correspondingly shaped indentations in wall 14 as will be readily seen , with such indentations being in opposed relationship to each of the five connector walls 26 ( see fig2 ). as a result of this configuration , it will be perceived that each of the connector walls 26 , at the region of front wall 14 , is somewhat y - shaped in configuration , with the base of the y extending from the corresponding notch 28 , and with the bifurcated portion thereof surrounding and defining the upper end of each zone 44 . as readily observable from fig1 and 2 , front wall 14 presents an effective thickness attributable to the noted y - shaped sections together with the bottom walls 46 and 46a of the respective openings 40 and 40a . in addition , the overall front wall 14 presents an upright inner surface in the form of respective arcuate walls 48 joined to the y - shaped sections and opening - defining walls and extending downwardly therefrom for joinder with the concavo - convex walls 22 . the arcuate walls 48 in turn define an upright abutment surface for the end of a fluorescent tube situated within each corresponding region 24 . rear side lip 20 is provided with a plurality , here seven , of upstanding spacer nibs 50 . as illustrated , the nibs 50 , in the depicted embodiment , are located at the ends of the lip 20 , and just to the left of each recess 36 . the purpose of these nibs 50 will be made clear hereinafter . each of the concavo - convex wall sections 22 include a stepped , arcuate , end cap - receiving wall portion 52 which extends rearwardly from each associated wall 48 and terminates at the frontmost end of the associated notches 28 as shown . the wall portion 52 as indicated receive the metallic end caps provided on the fluorescent tubes . the remainder of the concavo - convex wall sections extending rearwardly from the portions 52 to rear wall 12 are in the form of alternating downwardly and upwardly opening , vertically spaced apart arcuate tube - engaging wall sections 54 , 56 . that is to say , the majority of the length of each concavo - convex wall section 22 includes a plurality of axially spaced apart , arcuate , upwardly opening and diverging wall sections 56 presenting a radius of curvature conforming to that of the sidewall of a fluorescent tube . these spaced apart wall sections 56 , at their respective side margins , merge into and form a part of similarly curved main sidewall portions 58 which extend upwardly and are integral with the upper connector walls 26 . the concavo - convex walls 22 further include a second plurality of downwardly opening and diverging wall portions 54 which similarly have a radius of curvature conforming to the sidewall of a fluorescent tube . the respective marginal ends of each wall section 54 are joined with upwardly extending walls 60 ( see fig8 ) which extend upwardly to merge into main wall portion 58 . the alternating walls sections 54 , 56 are joined together by means of vertical walls 62 in order to maintain the wall sections in vertically spaced relationship to one another . as best seen in fig8 each upwardly opening wall section 56 is spaced above the adjacent wall section 54 . indeed , the lateral side margins of the wall sections 54 extend slightly below the bottom edge of the sidewalls 16 , 18 , and rear wall 14 . each of the wall sections 54 , 56 is provided with a plurality of relatively small cushioning striations or ribs 64 formed therein during the vacuum forming process of the dunnage support 10 . in like manner , each end cap - receiving wall portion 52 is similarly striated . hence the wall sections 54 , 56 each present an undulating , tube - engaging surface . the element 10 is formed in a female mold so that the thickness of each of the upper connector walls 26 , 30 is greater than that of the lower downwardly opening wall sections 54 . indeed , the thickness of the endmost portions of the wall sections 54 are on the order of 0 . 004 inch , and are effectively transluscent . on the other hand , the connector walls 26 , 30 are virtually the same thickness as the starting sheet material , or preferably about 0 . 014 inch . attention is next directed to fig9 which depicts a vertical stack 66 of interfitted dunnage supports in accordance with the invention . this stack is made up of two particular embodiments of the dunnage supports , namely the supports 10 fully described above , together with alternating supports 10a . the supports 10a are in all respects identical with the supports 10 , save for the fact that in the supports 10a , the nibs 50a thereof are laterally offset from the nibs 50 of the supports 10 , and the ledges or platforms thereof ( not shown ) are laterally offset from the platforms 42 . as a consequence of this construction , it will be seen that the nibs 50 , 50a alternate in a stairstep fashion throughout the stack 66 ; furthermore , the spacing platforms of the supports 10 , 10a similarly alternate in a stair - step fashion . by virtue of this configuration , each of the nibs 50 , 50a contacts the planar underside of the lip of the support next above in the stack ; likewise , each individual set of ledges or platforms engages the full heighth wall of the y - shaped section of the next adjacent support . the heighth of the nibs and the vertical recess of the platforms are correlated so as to maintain an even spacing between individual supports about the entire periphery thereof . this prevents full nesting of the respective supports 10 , 10a and effectively presents a series of substantially even , elongated spaces 68 between individual dunnage supports in the stack 66 . as a consequence , the stack 66 can be placed in automatic dispensing equipment , and the spaces 68 afford adequate clearance for the insertion of dispensing equipment between individual supports in the stack . thus , such dispensing equipment can be used to good effect to achieve easy , high speed automated dispensing of the individual supports . although pvc having a thickness of 0 . 014 inch is the preferred sheet material for use in forming the supports of the invention , other current or future equivalent materials may also be used . for example , it is believed that thermoplastic polyester or polyethylene terephthalate synthetic resins can also be used to good effect in the invention , with the thicknesses of these materials being substantially the same as outlined above . in order to provide the most advantageous protection for the fluorescent tubes , it is preferred to employ synthetic resin materials having a durometer value ( shore d per astm d - 2240 ) of from about 80 to 90 ( most preferably 84 ), and a modulus of elasticity of from about 400 , 000 to 440 , 000 , astm d - 790 ( most preferably 420 , 000 ). the most preferred pvc material further has a specific gravity 1 . 35 , astm d - 792 ; a tensile strength of 6750 psi , astm d - 638 ; a tensile modulus of 315 , 000 psi , astm d - 638 ; a flexural modulus of 420 , 000 psi , astm d - 790 ; and a deflection temperature at 264 psi of 58 ° c ., astm d - 648 . in addition , the various structural features of the dunnage supports assures that a package of fluorescent tubes with individual supports between respective layers thereof can withstand potentially destructive impact forces . that is to say , a given package containing four layers of tubes would make use of five dunnage supports at each end of the tubes , with four of the supports receiving the tubes as illustrated in fig8 and with one support being inverted . in any event , actual testing with the dunnage elements hereof has proved that they are fully capable of supporting and protecting fluorescent tubes in a manner at least equivalent to conventional pulp dunnage supports . such protection is believed to stem from the inherent flexibility of the synthetic resin material , and also by virtue of the striations 64 provided on the tube - engaging surfaces . furthermore , the various recesses such as the notches 28 and zones 44 , afford a controlled collapse to the dunnage elements which has been found to safely absorb potentially destructive forces . in addition to the foregoing , it has been found that it is advantageous to provide a spacing between the longitudinal axes of adjacent pairs of tube - receiving regions 24 slightly differently than the spacing between other pairs of axes . this slight differential is in itself believed to enhance the protective function during an impact situation . to further enhance the protective function , the shape , spacing , contours , dimensions and ribbed texture of the areas 54 , 56 , 58 , 60 and 62 are individually shaped to be slightly different from one another . finally , it will also be noted that the central connector wall 26 is slightly wider than the remaining connector walls on either side thereof . this not only enhances the strength of the central section of the support , but also facilitates automated insertion of thin vertical corrugated material between the central tubes during the packing process . as indicated above , a prime feature of the present invention resides in the provision of dunnage supports designed to only incompletely nest in a stack thereof so as to present uniform spacings between pairs of elements and thus facilitate machine dispensing thereof . while in the preferred form of the invention use in made of an alternating nib and ledge arrangement respectively located along the rear and front side edges of the supports , the invention is not so limited . thus , it will be appreciated that there are a multitude of ways to form spacing elements in the supports themselves in such a manner as to insure the partial nesting feature described above . all such equivalents are therefore deemed to be within the spirit and scope of the present invention .