" Wait a moment, there is something and a very important thing which you have forgotten. Your plate-holder will show on which side is the exposed plate, but suppose you go on now and take another picture and then, as you have this time, put the plate-holder away without making a memorandum, how shall you be able to tell on which side is either particular plate or ex posure which you have made?" " Yes, you see you have forgotten to make the proper entry in your note book, which we will now proceed to do as follows: This was plate-holder B in your note book, therefore, opposite that letter, you mark now in the proper column the time, six seconds; in the next column the size of the stop, f32; the next column we will write 10:30 B, which will stand for bright; then the subject, the church by the river, and the date.
While we are making these minutes in the note book the two younger boys had gone ahead with their cameras. When we overtook them we found them both focusing on a very pretty little cottage under the trees. They had both selected a good position, but were having some difficulty in deciding upon the proper object to get their focus upon. One had focused upon the trunk of a tree which stood about half way between himself, and the cottage, though a little off to one side. He had chosen this to focus upon because the sun was shining upon it, and it looked so clear on his ground-glass. The cottage itself was very much out of focus, and it was very indistinct and somewhat blurred. As the cottage was the principal part of the picture he readily saw that that should be the object to show the most distinctly upon the ground-glass. The other boy had focused correctly upon the cottage, but did not notice that his camera was not level, so that in the picture the cottage seemed to be sliding down hill. This is one of the first points always to be noticed, that the camera must be level so that the line of the horizon as shown upon the ground-glass may be level. Both of the boys had to use their sliding fronts so as to bring into their pictures the tops of the trees which were close to the cottage. They decided to use the same size of stop as that which they had just seen used before.
" Now our first picture, the one of the church, which was out in the bright sunlight, was made with an exposure of six seconds, but in this case we are taking a picture of a house of a light drab color, under and shaded by trees. The shadows of these trees, you will notice, fall across the roof of the house and also nearly cover one side. From this view there will be very much less light thrown into the camera than from the previous one, and therefore we must give it longer time. We cannot tell the exact time to give for a view of this kind. It would not be easy for any one to tell the exact time required for any particular kind of plate. There are no exact rules to give in determining correctly the time required for different views. We have to learn this by experience, keeping a careful record of every exposure and giv ing all the particulars, and before you are aware of it you will learn accurately about the correct time to give for every ex posure. The time of the year, the time of day and the state of the atmosphere, all of these govern the time for exposing the plate.
In October, November and December, January, February and March, the quantity of the light is very much less than in the ether six months of the year, the greatest amount of light be ing, of course, at the time of the year when the sun is the highest in the sky. As these are comparatively slow plates which we
are using, we shall try to give them enough and aim rather to give a little longer time than we think may be necessary, rather than to run the risk of giving too short a time. If the exposure is too short no amount of developing will bring out a picture on the plate when there is none there; but if the time is a little too long we are able by care in developing to bring out a picture all right. In this case, therefore, suppose we make the time 12 seconds, which would certainly not be at all too long if we were aiming to make a picture simply of the shadows alone. There is an old saying, which is growing to be an adage in photogra phy, Expose for the shadows and let the lights take care of themselves.' It is a good rule to follow." " Now, do not forget to cover your camera carefully with your focusing cloth before you draw the slide from the plate holder. It may be that your plate-holder is so tight and fits so closely to the camera that no light can possibly get between them, but there is danger of the plate-holder or camera warping a little, or a little dust or dirt getting in to prevent the two fitting together closely and thus leaving a space for the light to get in, so it is always safer to cover the camera with your focusing cloth and avoid the risk of the light fogging your plates." "Now you are all ready; be sure to count your time care fully." "That was right, you gave the time just right and you were very careful about replacing the caps on the lenses. Before you replace the slide remember about putting it squarely into the plate-holder and with the dark side out." " 0, one of you forgot to take out the slide, so of course, you have no picture on the plate and you will have to try yours over again." While he is getting ready to make the exposure again, Henry, who has the 4x5 camera, has taken out his plate-holder and placed it in his focusing cloth, and goes across the road, where he sits down under the deep shadow of some. bushes. Pretty soon he comes back, and says that there must be something the matter with his camera as he had just looked at the plate and there was not the slightest sign of a picture on it. He had made two mistakes. He supposed that exposing the plate for a pic ture made some change in the appearance of the plate, and he also supposed that he could look at this plate in the shade with out danger of injuring it. The plate which has been exposed for a picture does not differ in appearance from a plate which has not been exposed; the picture on the plate is only brought out afterwards by the development. And the moment he drew the slide to examine the plate in the shade, that very moment the light fogged his plate. The plate can only be looked at in the dark room by the aid of a dark lantern. We mean, of course, a plate which has not been developed. This is not the first time that we have seen this mistake made, as once before we came across a young man attempting to fill his plate-holders under the shade of some low-branched trees. He filled his plate-holders, of course, but with plates which he had ruined in so doing.
So once more Henry puts his plate holder in the camera, and makes another exposure of the same view. It was such a pretty view that he wanted to use it for his first one.