From: smith@mrcnext.cso.uiuc.edu (Greg Smith)
Subject: Re: Changes to FAQ
Organization: University of Illinois at Urbana
Date: Tue, 13 Oct 1992 13:26:00 GMT
Keywords: FAQ

A *nice* addition to the FAQ indeed!  A couple of comments from my 
experience with camera payloads:
	
> 1.1 Camroc - The first purpose-designed rocket camera. Designed by Estes and 
>    sold from 1965 to 1974. A marvel of simplicity, it was patterned after 
>    several homebrew cameras of the early '60s (see 2.1.1). It was simply a 
>    cylindrical body that held the film topped by a hemispherical nose that 
>    was flattened off to accept the optical window which the forward facing 
>    lens looked through. One shot per flight on "Astropan 400" (Kodak Tri-X) 
>    cut into a 1 1/2" dia. round negative. Easy to process at home. Extremely 
>    valuable on the collector market.

You might want to add that the Camroc required push-processing the Tri-X 
to ASA 1200 (officially; most of us used 1600) to have a hope of a 
reasonable exposure.  At one time there were quite a few homebrew 
modifications to the Camroc floating around.  Most popular was 
substituting a 3-element glass lens from Edmund Scientific for the 
standard plastic lens; it gave much sharper and better color-corrected 
results.  I have also seen a wide-angle variation with yet another 
Edmund lens that required cutting the forward body section of the Camroc 
down to a much shorter length.  (As someone pointed out at the time, the 
Camroc lens was a short telephoto relative to its film format.  It 
doesn't make sense to send a rocket up as high as possible and then use 
a telephoto lens to get a SMALLER angle of view; it's a wide angle you 
really want, so you can get more in the picture from a lower, 
easier-to-aim flight with a smaller motor and less risk of losing the 
camera.)  Several people flew color slide film in the Camroc, but 
high-speed color films were pretty terrible at the time; the ASA 1600 
print films available today would probably work very well in it.  

> 1.2 Cineroc - Estes' second foray into camera payloads, the Cineroc 
>    was *much* more sophisticated than the Camroc. This was a full bore 
>    8mm movie camera crammed into a package not much bigger than it's 
>    predecessor (although more aerodynamic). The lens looked aft via a 
>    hooded mirror and it shot ~15 sec worth of flight time at 2X speed 
>    (30 sec projection time) on Super 8 Ektachrome 400 color film housed 
>    in a custom cartridge.  Intro- duced with much fanfare in 1969, it 
>    lasted only 5 years before its plug was pulled in 1974. 

Although the Cineroc was *specified* to run at 31 frames per second 
(which should produce about a 1.7:1 slowdown when projected at 18 fps, 
the standard silent projection speed), the four or five of them that I 
owned and tested all ran around 17 - 20 fps, resulting in more or less 
normal-speed movies.  I never considered that much of a problem because 
it also meant the film ran longer during the flight.

The film was not an ASA 400 material; it was an ASA 160 instrumentation 
film on a polyester base which was probably adopted because it was the 
only daylight-balanced super 8 film available.  (Since all normal super 
8 cameras have a built-in 85A filter, most of the common color film 
stocks were sold in 3400K, "type A" color balance for incandescent 
lights and you used the filter when outdoors.)  Its emulsion was more or 
less identical to 7241, a 16mm Ektachrome stock familiar to TV news 
cameramen of that day.  Home processing was possible in the old E-4 
Ektachrome chemistry, but do-it-yourself E-4 kits have since gone the 
way of the Cineroc itself, so home developing is more or less out of the 
question today.  In later years, most of us who have continued using the 
camera have switched to Ektachrome 160 Type G, which is a universal 
("equally bad in all light") color balanced ISO 160 stock.

As I've recounted here before, the Cineroc was introduced in the 
1970 Estes catalog, and shipped several months late.  I placed my order 
within days of the original announcement and did not receive my camera 
from the first production run until around the end of August, 1970.

"N" size alkaline batteries (much better than the original carbon-zinc 
ones that came with the Cineroc) are widely available now, and the new 
film stock (which is available off the shelf now, not special order like 
the one Estes originally chose) is sharper and less grainy than the old 
stuff -- both of which actually make for easier and better Cineroc 
results today than when the camera was first introduced.  You do need to 
enlist the cooperation of a custom film lab to deal with the nonstandard 
lengths of 8mm film, however.

There are several little toy motors that make decent substitutes for the 
one in the Cineroc, and it's too bad they couldn't recreate that lens 
mold ...

> 3.2 Broadcast - Broadcast video has had more success, but complicates the 
>    process by adding a whole new technology. While the components that ride 
>    in the rocket have no moving parts, you must add transmitters and antennae 
>    to you vehicle, plus receivers and recorders to your GSE.  License-less 
>    video broadcasting is allowed by the FCC, but the power limitations raise 
>    more problems. Omni directional broadcast antennae are easy to track, but 
>    the signal strength drops off *fast* (inverse square law).  Directional 
>    antennas concentrate the signal, but require that you track the rocket, or 
>    hope that it doesn't go too far off course! The HUVARS group is working on 
>    this technology, and the _Tripolitan_  is promising an article on it RSN 
>    :-)

The word "broadcast" has a specific legal meaning ("intended for 
reception by the public at large") in FCC legalese that I don't think 
you want to imply here; "transmit" is more appropriate.  

There is a good article on rocket TV from an amateur radio perspective 
in the August, 1990 issue of _73 Amateur Radio_, p. 52, written by Bob 
Rau, N8IYD (any relation to Richard Rau of THOY?  I don't know, but they 
ARE both in Michigan ...).

This is an area I'm interested in too (my professional background is in 
photography, film and TV, and other hobbies include ham radio), so I 
hope to have more to contribute later as I continue to get back into the 
hobby.

Incidentally, I have two Camrocs that I doubt I will ever want to fly 
again (I have three Astrocams which are so much easier to use for now, 
and eventually I want to do a motor-driven 35mm), as well as four or 
five extra film pack sections, so if any collectors are interested 
please make me an offer.  They have been flown some, but are complete 
and in good condition.

Greg Smith N9LHI
NAR 15881 * TRA 1974
smith@mrcnext.cso.uiuc.edu

Newsgroups: rec.models.rockets