AREA NEWS
C.R.C. MEMBERSHIP SECRETARY POST.
After a long successful term as Mem. Sec. Bob Lewis is to stand down at the end of the 1989/90 season. If you would like to take on this important post please write/phone the Hon. Secretary, Ron Croad, for full details.MANCHESTER MICROSCOPICAL AND NATURAL HISTORY SOCIETY
Bob Lewis has forwarded some details of this organisation which is interested mainly in the study of things to be seen through the microscope. A copy of the Society`s newsletter suggests that it has a some what scientific bias, but nevertheless offers a fascinating insight into some of their methods of studying and photographing through the microscope. For further details contact:- Mr. R. Winsby, Hon. Secretary, 214. East Lancs, Road, Swinton, Manchester. M27 1QJ.TECHNICAL ADVISERS
Don`t forget that we have our own technical officers who are willing to provide advice on matters of processing reversal films etc. They are:-
Brian Savage, Culver Keys, Broadmore Green, Rushwick, Worcester, WR2 5TE
Kevin Craske, 17. Providence Place, Briston, Melton Constable, Norfolk NR24 2HZ. 01263-860602
Lawrence Edwards, 10. Middlemoor, Leeds, LS1 2DW. 01924-223226.
Whilst both Brian and Kevin have been with the Club for some time, Lawrence is a new member, although quite knowledgeable in the field of processing.BAIT & SWITCH Peter Guy - Area 20.
An interesting article in an American photographic magazine reveals a big sales fiddle which is going on at the moment called "Bait & Switch". A good independent lens such as a Vivitar is advertised for sale by mail order at a very low price. When a customer rings to order one he is told that some are faulty and the whole shipment has been sent back, but they can are offer an alternative, say a "SUKKER" (made in Korea). This is as good, if not better, than the one advertised and at the same price. The catch is, of course, that it is of very inferior quality and once received cannot be returned, unless the item is faulty. It cold only happen in America, or could it?CHANGING THE pH Nick Williams - Area 20.
If you have measured the pH of a solution and found it not to be to your liking, then it can be changed as follows:- If the pH is too low, raise it by adding some extra alkali. This can be conveniently done in the form of a 10% solution (i.e. 10gms per 100cc) of sodium hydroxide. Add a little at a time (such as 1cc or less) and keep measuring the pH until you get to the desired value.To reduce the pH you need to add dilute acid. If you can get hold of it, 10% sulphuric acid is ideal and as with the alkali, you add a little at a time. If by chance you can get hold of some of the CONCENTRATED sulphuric acid, be very careful as it is VICIOUS stuff. In particular be very wary of how you go about diluting it. The acid has a strong affinity for water and heat is generated when the two come in contact. You must ALWAYS ADD THE ACID TO THE WATER and not the other way around. If a little water is added to the concentrated acid it will vaporize immediately causing concentrated acid to spurt up. For the less adventurous amongst us, Glacial acetic acid can be used instead, but don`t forget to reduce it to a 10% solution first.
WAYMASTER CRYSTAL WATER FILTER JUG George Sparkes - Area 22.
Members may be interested in this filter for photographic purposes, although we bought one to purify drinking water after seeing in "Which" magazine of Feb. 89. The clear plastic jug holds two litres of water and is fitted with a removable filter cartridge. It takes under five minutes to filter a litre of tap water and removes lead, trichloroethylene, polycyclic aromatic hydrocarbons from both hard and soft water, aluminium from soft water, iron and mangonese from hard only and removed nitrates. It costs under œ11 and replacement filters which last a month costs £2.25. Since using it the inside of our electric kettle has become bright and shiny (me too probably!). I filtered the water for processing solutions and found that the pH of the tap water was reduced by 0.2.
(Editor`s note - Ron Croad has the same filter jug and has reported a reduction from 7.2 to 6.4 in the pH reading. The filter jug certainly has a magnificent effect on the pH of the water - and makes the tea taste much better).ONHAR SLIDE COPIER Pete Guy - Area 20.
I recently purchased an `Onhar` slide copier second hand. It was in a box and in good condition, but there were no instructions with it. If any member has one of these I would be very grateful if I could photocopy them, or I would pay the money for photocopying