Details

Category: Multi-gauge Projectors

Specto

 

 

SPECTO

 

For use of the Specto for Ultra Pan 8, click here

There is now lots on Specto, so a separate page is indicated. Aunt Em has had some Specto correspondence, too. The Ultra Pan 8 page also has stuff on it of more general relevance, tho' I haven't bothered to repeat it here.

     

This is a picture of a 9.5/16 Specto from the Picture Gallery; there was also an 8/16 model. Single-gauge 8, 9.5 and 16 machines were made, too. Today, only the 9.5 and 9/16 machines seem to be in any demand; 8 and 16 machines, often in fine condition, are more or less given away. One day I must see if it is possible to transplant the 9.5 bits from a knackered machine to a pristine 8mm one. (Colin Loffler says he has done it He was right - I have it now). My 8mm-converted-to 9.5 (by Colin Loffler) Specto performs very well; the only slight hitch I have found is that the 9.5 framing needs to be at one end of the available adjustment. This means that when I want to open the lens housing to clean the gate, I have to slack off the framing a bit before the thing will open, and re-adjust afterwards. But the light output with original lamp is excellent.

I have come across what I fear may be evidence that Spectos, too, suffer from the dreaded Mazac disease. I had a 9.5/16, converted to QI, but non-functional because on of the raised "bearings" for the mech, on the plate behind the lens holder, had partially broken away and stopped the claw mech working properly. On closer examination, it looks like this was not the first time - two others seem to have been replaced. When I dismantled it all, the gearbox was very stiff and some of the individual gears were very tight in the bearings. I tried to remove the shutter shaft, but this actually broke the entire plate in two - very Mazac. This didn't matter as it was already well past it and I was deeply suspicious that Mazac had a part to play in making some of the shafts very stiff in the bearings. Worse, one of the 800' spool arms just broke apart in me 'ands, 'onest guv. This could probably be fixed if I needed to.

 

                     

                   

I have labelled bits in pic 7; 1 is the raised "bearing" referred to above - you can see the side has broken away and it simply would not hold the shaft it was supposed to support. At 7, the same thing seems to be happening to part of the hinge. 2&3 seem to me like replacements for broken parts (held by a screw from the other side) and I have suspicions about 5&6, tho' I may be wrong. Some of these are seen closer up in the next pic.

Anyway, to return to the plot, I also had a very nice 16mm Specto 750 with, as you would expect, a 750w mains lamp and the larger-barrelled lens that appeared in some late Spectos. I managed to transplant the 9.5/16 parts to the 16mm body, tho' I had to cut off a bit of one shaft which, as it was hardened steel, was tricky. Hopefully, I now have a decent 9.5 (and 16) Specto that has probably had less use than the poor, tired old 9.5 machines one sees so often. And it's gold and shiny. Done an 8mm to 9.5 one as well, now.

                         

There are at least 2 quite different types of front gate fixing (quite apart from the adaptable gates for dual gauge machines). There is the simple single screw top and bottom type, with a large gate cut-out to miss the claw, and the more sophisticated four-point jobbie, used with a retractable claw. The latter seems to go with the wire gate-opener shown in pic 3; the earlier type has a cam immediately next to the handle, which works on one side of the gate only. Great care is needed with gates, because the screws are small (tiny in the case of the one that holds the gate-opening lever in place) and the threads are into Mazac or something very similar - it is all too easy to strip the threads.

The more complex arrangement of the retractable claw involves a different film retainer for the sprocket - earlier ones are straight and simply ride on the sprocket itself, and so, presumably, on the film, hence perhaps the change. Incidentally, I was wrong about 2&3 ; they seem to be the holes for the retractable pin that holds the rollers above rather than on the film.

I have mentioned earlier a problem with my 8mm-converted-to-9.5 Specto that I got from Colin Loffler. To open the gate, I have found it necessary to slack off the framing screw; the adjustment for 9.5 is close to the bottom of the available travel and I can't else open the gate. Then I have to re-adjust afterwards. However, I noticed while working on the Spectos that there is a small washer, really a spacer I suppose, inserted just above the lower hinge. I've not spotted it before; it may not always be there, having gotten lost over time. And I don't know what it does, tho' it is clearly original as it matches the colour of the projector. So I have removed it from the offending projector to see if it overcomes my little problem.

Finally, I have often noticed that the Specto lower arm leaves a 9.5 900' spool too high, so that it can interfere a little with the bottom of the projected picture. This presumably relates to the 800' capacity, which was all Specto claimed. On the ones I have been working on, I have noted that there is considerable scope for lowering the arm by filing away the "elbow" on the rear of the spool arm, which contacts that lump cast into the main body to support the arm. I made sure there was still room for a 1000' 9.5 reel, as I use these a lot, but there's no point in leaving the arm higher than need be.

In the 9.5 section, under Silent to Sound, are details of Specto sound units, repeated here as page 2 of this article.

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The problems with adding sound to a silent machine are many. Among them is the sheer speed of operation, 50% faster than envisaged at the design stage. One has to accept this proved no problem with the Gem mechanism. However, the Specto already had a mechanism where the claw operated twice per frame, being held back from engaging the film on the second stroke. One would expect wear if not worse. Probably the biggest problem is controlling the speed - a simple electric motor tends to gain speed as it warms up and to vary its speed with variations in load. Together with smoothing the film across the sound reader, this could significantly affect sound quality.

Associated Cine Equipments (ACE) of Erith, Kent, made add-on sound units for Gem and Specto, for both 16mm and 9.5mm, with 12 watts sound output claimed. They were sold either as complete units with projector, in a case, or separately. I have a copy of a 1950 advert. Prices were:-

Gem, complete projector 9.5 81 12 0 Sound unit only 44 2 0

16 92 10 052 10 0

Specto9.5 95 12 0 54 10 0

16 99 10 0 54 10 0

The Specto unit was designed for the standard 400ft capacity model; the lower arm remained in place, but folded down against the front of the projector. A unit to take the Educational model was available at a slightly higher price. The unit itself had a 900ft take-up; a top spool extension arm was available for 10s. 6d. I have to say that these prices look stupendously high, considering what average weekly wages must have been. A test Report on the 9.5 unit was published in the October 1959 issue of Amateur Cine World (ACW). Here is the text.

"The outstanding feature of these Sound Units is that no modification to the projector is required - an important point. There can be no doubt that the Specto is a difficult machine to convert as the motor occupies the very place where one would wish to put the soundhead. It is interesting to note, therefore, that Associated Cine Equipments have located their soundhead after the lower sprocket, which means that the film is pulled through the soundhead by the take-up reel.

Tests show that this unconventional procedure works extremely well. The sound is very good, comparing most favourably with that from other 9.5mm machines. Our critical ears detected a small amount of wow, but this would doubtless not be noticed by the average audience. Obviously, it is essential to use reels that are not bent, and take-up belts of the correct type, to maintain smooth film travel. We tested a 9.5mm standard (100 watt model) Specto projector and Sound Unit. The unit is solidly built from aluminium castings, and the black crackle and plating match the finish of the Specto exactly. The appearance of the complete unit is unified and quite pleasing. (Note that the pictures are my 9.5/16 machine, with the longer arms cannibalised from a 16mm machine. I had to remove the lower arm; with 400 ft capacity, the arm would fold down between the motor and the sound unit - MAS).

The Sound Unit incorporates the complete soundhead and amplifier very neatly. There are no loose "extras." The Specto is simply placed on the platform of the unit. Adjustable locating bars are provided to allow for any small differences in the position of the film path on different Spectos, so that the projector can be accurately lined up with the sound head.

The soundhead

The sound head itself, located on top of the Unit, scans the film on a rotating drum in the customary fashion. The sound drum shaft, mounted in ball races, carries a solid flywheel 4.75 in. diameter and nearly 0.5 in. thick. A roller below the drum provides the necessary drag, and holds the film onto the drum. The film is guided between a flange on one side of the roller, and a flange on the opposite side of the scanning drum. A roller above the drum carries the film round to the take-up reel.

The photocell, a midget type CG-10, is fitted in a very neat plug-in holder. The cell protrudes into the hollow interior of the scanning drum, where it directly picks up the light coming through the sound track - there are no mirrors, etc., to get out of adjustment.

The optical system - the standard projected slit type - has a relatively long focus objective lens, so there is plenty of room between the optical system and the drum for the film to be threaded comfortably and easily. The 4 volt 6 amp exciter lamp is fed from the transformer with raw A.C., but due to the high amperage and high thermal capacity of the thick filament there is negligible mains hum. A neat feature is that the exciter lamp also illuminates the control panel through a plastic window.

Compact amplifier

The very compact amplifier, in which the valves are lying 'on their sides', permits the shallow construction of the part of the base on which the projector stands. Grilles above and below the valves provide ventilation. The valves, all standard International Octal types are; 6J7 first stage, followed by double triode 6SN7 amplifier and inverter respectively, and two 6V6 output valves in push-pull. The rectifier is a 5Z4. The amplifier has an output of approximately 12 watts. We obtained ample volume in a large room with the volume control in about the half way position. From this we should judge that a 250 watt model Specto and the appropriate Sound Unit would give a creditable performance in a small hall.

A socket is provided for a gramophone pick-up to be plugged into the amplifier. The pick-up socket feeds into the second stage of the amplifier. A change-over switch on the control panel permits selection of film or gram. No provision is made for balancing level and tone of the two; the pick-up would normally be balanced externally to the film. The switch for film/gram changeover is definitely a good point for the amateur showman. No tone control is provided on the amplifier, which is set at a pleasing balance for film.

A small but important refinement of the Sound Unit is that the mains are plugged only into the Unit. A plug on the Unit provides current to the Specto. A good feature is that the same three pin plugs and sockets are used on the Unit as on the Specto itself, so the Specto owner's leads will be suitable for the Unit, and the three pins permit proper earthing of the metalwork. Both switches are normally left "on", and the machine operated from the control panel of the sound unit.

The amplifier is automatically switched on when the jack on the loudspeaker lead is plugged into the amplifier. A voltage selector for 200 to 250 volts (on the model we tested) is provided on the amplifier, which, like the usual transformer model Specto, is suitable for A.C. mains only.

The loudspeaker, a 10 inch Wharfedale of 15 ohms impedance, is contained in an attractive leatherette covered wooden case, which also serves to carry the Sound Unit when not in use. The take-up arm is also carried in the case. Some 30 ft. of speaker cable is provided, and is wound around brackets in the speaker case for storage. A well-made carrying case for the Specto projector is available as an extra; this is covered in grey leatherette to match the speaker case. A monitor speaker is available for those who wish to use the machine in a separate room or operating box.

Spool arms

The Specto we used had 400 ft. spool arms with an extension piece supplied by A.C.E. fitted to the top arm to enable it to take 900 ft. reels. A machine with Specto 800/900 ft. arms would not require this. When the Specto is placed on the Sound Unit, the lower (400 ft.) spool arm of the projector is in the folded position. A lower 800/900 ft. type arm would have to be removed before placing the projector on the Sound Unit.

The lower spring belt is replaced by a small rubber belt. It is this which provides a positive drive to a double pulley on the Unit, and from there a spring belt provides the slipping drive to the take-up spindle. A special take-up arm for reels up to 900 ft. capacity is supplied with the unit, and screws to the front of the casting.

For the 16mm Units, a special 1,600 ft. lower spool arm is available. This does not take its drive from the projector, since that would no doubt place undue strain on the motor. Instead, the 1,600 ft. arm has its own induction motor drive and slipping clutch (as distinct from the better known practice of using a series wound motor with a positive to the reel but "electrical" slip). The separate motor, which takes its current from the unit, gives the best quality sound on large reels of 16mm., because it gives a smoother take-up and hence a smoother drive to the film at the soundhead.

To mask off the sound track when sound films are being shown, a simple slide-over gate mask (supplied with the Sound Unit) is fitted to the 9.5mm Specto. The mask fits behind the top screw which holds the front plate of the gate on the Specto, and is moved in or out of position with the finger after taking out the lens. We found that it tended to raise the front plate of the gate slightly, so a little care was needed when threading to slip the film into the gate without its meeting the edge of the front plate. No mask is, of course, needed on 16mm.

A nice feature is that tilting of the machine is provided by the two front feet of the Sound Unit. The Specto seems to maintain sound speed surprisingly well once the motor has been warmed up. Messrs. A.C.E can fit governors, but they do not feel that the extra cost is justified for ordinary usage. Further, they prefer the user to hold to their commendable principle that no modification should be made to the Specto.

Four models

Two models of the Sound Unit take the 9.5mm Standard and the Educational Spectos, while another two take the 16mm machines.

It will be remembered that the 16mm Specto has claws on the inside, whereas S.M.P.E. sound film normally requires the claws to be on the outside. To overcome this the film is run with the perforations "inside", and a reversing prism is supplied to go on to the projector lens. Special sprockets and relieved gate plates are also available. The new Specto "Dual" which has 16mm claws on the outside cannot be used on an A.C.E. 16mm Sound Unit, but is suitable for a 9.5mm Unit. The entire Sound Unit shows evidence of very careful planning, and the construction is extremely good. We should say that certainly it is a most attractive (and only - MAS) proposition for the Specto owner who wants sound (my italics) for home use or in a small hall."

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The Specto speed controller seems to be something to do with synchronising sound - what a fascinating find one of those would be. And now I do have one, thanks to Paul Schimmel. Here are the instructions. Also I have acquired an 8mm Specto wiv speed control fitted.

 

                    

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Pics 1-4, 6 & 7 above are most of a Specto leaflet. It has 6 sides, but is folded in a way that the bottom quarter of each page is somewhat separate. On pages 2 to 4, the print is the same way up as the main part and is shown with it. On the other three, the printing is upside down relative to the main part of the page, and these sections are the first three parts of pic 8. The last part of Pic 8 is from a second, later version of the leaflet; I only have part of this. The only clue as to date is the little note "3/57", bottom left of pic 7. This is obviously later, with higher prices, so the earlier one is before March 1957 - probably.

For completeness, I had included the instructions for a Specto. The thumbnails are here, but all the full size pix disappeared in the Great Software Disaster of 2015, and I cannot face re-doing all 25, so I have left the thumbnails and added a pdf SPInstrs.pdf.

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And a leaflet for a Specto analyser with a very odd colour scheme. Then a group of 3 older versions. The RH one has the inching button which is part missing on the LH one. Centre one has no button at all. And what about that 3-pin socket two of them have? What does it do? (If anyone knows of a source for the plugs to fit such sockets I shall be eternally grateful.) And it's not much better at the back- The centre one has a shaft protruding which seems to have lost its knob, but it's in a quite different place to the other two. I would much appreciate a copy, to buy or borrow, or a scan or even a photocopy of various editions of the instructions for these machines.

                        

I have since acquired a pair (greed!) of these obviously very late machines. Here are some pix.

              

I recently had a request from a friend for a working 8mm Specto. Always ready to help, I dusted one down. As usual, it gave me a bit of a fight. As well as a new main drive belt, oiling and new rubber feet to replace manky ones, one of the front adjustable feet was locked solid. It also threw a new trick at me. I was about to road test when I spotted that the claw was running the opposite way to the sprockets, so that when they (the sprockets) were operating normally, the claw was trying to push the film up instead of pulling it down. This had me floored for a while, but I finally figured out that, as the in-and-out and up-and-down cams were on two separate shafts, they must have got out of sync. Then it was a matter of loosening one and turning the other until it was right. It reminds me of another Specto, for another friend, which had the motor running backwards. That was a matter of swapping the leads to the brushes inside the motor.

Yet another friend expressed to me recently his disappointment with the light output from a 30v 100w Specto. Being a thoroughgoing sort of a guy, he looked up the original reviews and measured the light output from his machine. It was performing as per original; shows how much more light we like nowadays. The 8mm Specto above is a 240v 500w model, but I thought the light was still disappointing. Not helped by the fact that the 1" lens I first tried was so soft and fuzzy, with a big halo round the pic. I must get 'er indoors to type up what may have been my first ever venture into this writing-about-cine field, which was also about a Specto.

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Telecine Specto

I have made a telecine machine from a Specto, which involves a major and serious crime that I have constantly inveighed against and for which I can offer only a limited defence. Basically, it involved cutting the side of the lamphouse off a Specto and fitting a camera instead of a lamp. Let me start at the beginning. A year or so ago, Pat Moules and Tony Saffrey saw the machine made by the Welsh National Film Archive to help in the preservation of rare films on 9.5. Instead of the more usual approach, the camera was placed in the lamphouse and a light shone thru the lens barrel. They were fired with a spirit of emulation, as the results were remarkably good. Tony bought a camera and a lens, and muggins here was lumbered with the task of actually making a practical set-up.

The camera had only very limited attachment points - two screws top and 2 more bottom, all at the front end. I therefore made a pair of plates that used these holes to attach them, and left lugs sticking out from the plate at the rear for bolts to hold a rod at each side, which sort of grip the sides of the camera and ensure the plates don't move. You can just see one of the rods lurking at the edge of the black box at the rear, of which more in a bit. (As you can see, there are a series of control switches on one side so this has to be left clear.) To these plates I fixed two angle brackets, to which in turn is fitted a flat plate. This plate slides between guides on the plate in pic 2; the guides are hidden by the brass strips which overlap the plate carrying the camera keep it in situ. The face of the plate is covered in brass sheet, because I found alu on alu did not slide at all well. That's the trouble with what is essentially prototyping, which is basically what I am doing most of the time - you only find problems as you do things, then it's a choice of start again or find a work-round. The vertical plate is mounted with another angle bracket. You can see at the bottom of the vertical slide that the angle bracket is doubled. This was a late amendment to allow me to use trapped bolts, which you can see sandwiched between the brackets. In the underside view, you can see the big nuts (one smaller cos of lack of space) used for finger tightening, with holes for a tommy bar for full tightening. You can see on the left the extra screw into one of the columns needed to hold the back cover plate on.

Having gotten to this point, I turned my attention to the projector itself. Having removed the mechanism, and most of the stuff in the base, I fitted the posts you see here. They use the original holes for bolts which held a tranny, except for one I had to relocate as it was partially obscured when the mech was in place. They have a (long) screw thread at the bottom and are secured by nuts from underneath. I subsequently used the extra length of the threads as the mountings for a plate carrying the 12v power supply. I fitted an extra switch so as to power the camera and the light source separately. These rods support a flat plate on which the camera slide assembly described above sits. Slots in the angle brackets and in this plate allow for to and fro and side to side movement of the camera. Actually this wasn't the first job; that was fitting a plate to cover the shutter to protect both it and fingers.

I next turned to the light source. I Initially made a unit with a 12v miniature bulb I had to hand, but this has now been replaced by a rather more sprauncy LED array, as shown in these pix.

The little LED array in the first 2 pix (to give you an idea of scale, they are 5mm LEDs) sits inside a tube (pic 3), which is a nice firm-but-sliding fit in the Specto lens barrel. The other end is covered by a bit of plastic to act as a diffuser. The final pic here shows the underside of the base. The small tranny was originally in one of those bricks you plug straight into a socket, but I cut it open to fit in here. You will also note that I replaced the original Bulgin socket with a standard euro type. Wiring not quite finished yet in this pic and I dunno why that white jump lead is there.

All of this took place as a kind of avoidance activity before I could bring myself actually to bite the bullet and take a saw to the Specto. In the end, I justified it to myself with the thought that I could always make another 9.5 machine by switching parts from a dead 9.5 machine with an 8mm Specto - there seem to be loads of these, in good nick and cheap, and I know it can be done cos I've got one.

I finally steeled (aluminiumed?) myself and hacked away the side of the lamphouse so all this stuff I had been making could actually be fitted to the projector. Tony Saffrey brought along a bit of 16mm-reperfed-to-9.5 TV test card and we set it all up. These shots show our very basic lash-up and the amazingly good results we got more or less at once - I spose we didn't ort to have been surprised as the Welsh Archive had done it and all we did was copy. (I hadn't really noticed the shadow under "Pathescope" before).

What we found was that, as advised from Wales, we needed extension tubes between the "C" mount lens (F 1") and the camera. What we also found was that the standard sizes of 5, 10 and 20mm did not quite work - in the nature of things, we needed something between. Fortunately, all the threads on the lens and the tubes have enough length to allow the insertion of "washers" of various thicknesses that I made out of aluminium. We also found that the focussing ring on the lens itself made little difference, tho' it was a bit better at its minimum of about 18". The main impact on focussing was moving the camera assembly itself. However, latest advice from Wales suggests the same can be achieved by an adjuster on the camera which moves the CCD.

 

This is the thing more or less complete. You can see I made posh knurled knobs and all! At the top you can see a brace I fitted when it became obvious that the angle bracket mounting the vertical slide did not give enough stability. It pivots at the end you can see, and the other end is slotted to cater for movement of the assembly. The slotted end rests on a column, visible past the camera, which took the place of one of the screws securing the horizontal bed plate. Tony Saffrey expressed concern that the connections at the back of the camera could pose a problem in regular use and be prone to being bashed, so I fitted the black plastic box as a cover. The connections from the camera are led out to sockets mounted on the box, so in general use there is no direct mechanical connection to the camera. If the sockets in the black box cause problems, they can be far more readily replaced than those on the camera itself.

Various bits remain to be done - refitting the arms and the 16mm claw that I removed for some reason yonks ago so it will be a dual gauge machine. I have also fitted a switch on the front below the motor so that the machine can be left plugged in without the tranny being on. I have removed the rubber feet and have metal cross bars to fit in their place so it can all be screwed down to a heavy board for extra stability. (In fact, what I did was to make a sort of plinth, so that the machine can be operated without the front spool having to hang over the edge of a table. It also makes a space where a box for 16mm parts etc can be kept.)

Basically, my part is done and I shall hand it over to Tony and Patrick. I don't actually know how to actually record anything, tho' I did watch an MM M reel all thru. Running a film on a projector and watching it on a TV felt quite odd. Why am I betraying film in this way, you ask? Well, I don't feel that I am. What we are doing is taking advantage of modern technology to extend the use we can make of film. Do you realise that the high-grade frame enlargements in Flickers are copied by digital means? Just another dimension to our endlessly fascinating hobby.

November 2015

It is now a long time since I reported the above, and I should give you an update. There were 2 basic problems we found. First, the camera used an auto exposure, which responded rather slowly (relatively speaking, of course). The effect was that, after a title or dark scene, a following lighter scens had a frame or two over-exposed as the camera shut down the aperture, giving a moment of glare on the screen. It seems extremely difficult to find a small, cheap digital camera without this feature. The second point was the light source. Tony saffrey reported that the 3 LEDs tended to give brighter spots rather than an overall diffuse light. In fact, he said, doing away with the LEDs and just pointing the lens barrel at a bright day (not directly at the sun, of course) gave good results.

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 Been trying to find a 16mm Specto to loan out and find that pretty much all I have is Analysers. Here are some pix of one I played with.

                    

Note in pic 1 a single-frame button (arrowed) that you can push, when the speed control is set to zero, for very slow advance. The 2fps setting gives an intermittent motion - a couple of frames at a time. The 16fps speed seems slow, but not only is there no speed control other than the 0-2-16 lever, there is no inching knob either, its place being taken by a handle for backwinding. I don't understand most of the additional bits you can see in pix 2 &3. In pic 4 arrowed is what looks to be a twin-track commutator-like thing with brushes contacting it from the block to the right. In pic 5 you can just see the edge of the heat shutter that comes across for stills. Curiously, this seemed on this machine to make no difference to the light level, which leads me to suspect something is not working right. Anyway, you will be unsurprised to hear this machine, too, has joined the great projector conspiracy. The backwind handle, having been bent at its weakest point, not only broke but also now refuses to come off - it did once but not a second time.

The problem with Analysers as projectors is that the speed seems to be fixed and 16fps, on this machine at least, is just too slow for a modern audience. The light output, naturally, has to be reduced; this one has a 250w lamp. I need to understand them better; I have no idea for instance what the extra socket on the front is for. Has anyone got any instructions I can get a copy of? And does anyone know why there seem to be so many about - I only know of RAF use for analysing films of bombing etc; does anyone know of any other uses?

Here are some close-up pix of a dual-gauge 8/16 Specto.

          

 These give you some idea of how the gauge change is effected. Basically, all Specto's use the same gearbox; the difference between 8mm and 9.6/16mm machines is down mostly to the size of the sprocket drive from the gearbox. Here you can see the mechanism from the front that moves the main drive shaft on which are two sprockets. The iner, larger sprocket has a conventional arrangement, with the inner chain driving the two chain sprocket drives to the film sprockets. However, the operation of the gauge change lever operates some form of clutch which disengages the large drive sprocket and presumably leaves it to freewheel. the drive shaft then engaging with the smaller sprocket. The drive then goes via the outer chain to the outer of the two bottom sprockets, which is rigidly connected to the inner sprocket, so passing the reduced speed drive to the upper sprocket via the inner chain. Clear so far? The Specto people were highly ingenious, as even this limited example shows. The analyser machines were a whole order of magnitude more complex.

Incidentally, I no longer quite understand why I included the middle pic,which seems to show some sort of heat filter, usually associated with a still frame or very slow motion capability. It mite belong to an analyser rather than this machine.