This section is from the "Studio Light Incorporating The Aristo Eagle - The Artura Bulletin 1910" book, by Aristo Motto. Also see Amazon: Studio Light Incorporating The Aristo Eagle - The Artura Bulletin 1910.
From time to time we have had requests for a proof paper that cannot be toned, which leads us to believe that quite a few photographers have had trouble with some of their customers having proofs toned and then forgetting to order finished prints of the sitting.
This is not only loss of business but it is also very undesirable to have proofs from unre-touched negatives toned and kept by customers as examples of your workmanship. The extent of the damage that these half finished pictures may do cannot be definitely traced, but no doubt Mrs. A, who has had some of your proofs toned, will show them to Mrs. B and Mrs. C, much to your detriment, as Mrs. A. will take care to explain that the pictures were made at your studio, and will possibly add that she didn't care enough about them to place an order. This leaves a final impression in the minds of Mrs. B and C that you are a good photographer to avoid in the future. The damage may extend still further, because when Mrs. B or C are offered the opportunity to discuss photographs they will be very likely to mention the Mrs. A incident.
If you are a good photographer you use every precaution to prevent finished orders from leaving the studio that are not up to standard, and naturally you object to proofs being kept by customers for the same reasons.
Many photographers insist that all proofs be returned at the time the order for finished prints is placed, thus voicing their disapproval of allowing proofs to remain in the hands of the customer. This insistence on the part of the photographer, however, is likely to cause friction - a thing that should be avoided as far as possible.
To prevent customers from having proofs toned we offer the following suggestion which solves the problem:
We get this from an Ohio photographer who has used it successfully. Mix up a solution of benzine and paraffine - say about a half pint of benzine in which is dissolved a piece of paraffine about the size of a walnut.
This is applied to any part of the face of the proof with a brush and does not change its appearance in any way. The benzine rapidly evaporates, leaving a thin transparent deposit of paraffine on the face of the proof which will repel toning chemicals and prevent toning.
Customers acting in good faith will not suffer any inconvenience - in fact they will never know you have taken any precaution to protect your proofs. The unscrupulous customers who try to take advantage of you by having proofs toned will find themselves trapped, as the parts of the proofs which have been treated with benzine and paraffine dressing will be of a sickly yellowish color when toned, in sharp contrast to the remainder of the proof which will tone properly.