enlarger alignment

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Hi folks,

Just wondering if someone has a good procedure for enlarger alignment, without the use of that special tool sometimes used for aligning Omega enlargers. Thanks!

Chris

-- Chris (gazebophoto@hotmail.com), August 30, 2001

Answers

Chris: Here is the method I have used for years and it works with no problems whatsoever: First, get a small level and level the enlarger baseboard on the table, side to side and front to back. Use wood or cardboard shims to get the baseboard level. Second, insert an 8x10 sheet of glass into the negative stage and lower the head to hold the glass tightly. You may want to tape the edges of the glass to protect yourself. Lay the level on the glass and level the negative stage side to side and front to back. Then place the level across the lens flange and level the lens stage. Recheck all, and the enlarger should be in good alignment. Now take a fine tip felt tip black pen and draw lines either on the piece of glass or a clear negative from side to side, front to back and corner to corner. Now place the glass or negative in the enlarger and check the focus with the lens wide open. It should now be sharp overall. You may need to stop down to bring the corners into sharp focus, depending on the lens. If the corners are slightly soft with the lens wide open, they should be equally soft at all four corners. This should do the trick for you.

Regards,

-- Doug Paramore (dougmary@alaweb.com), August 30, 2001.


I haven't set up my 4x5 enlarger yet--still cleaning the basement, but when I had a Beseler 23C II, I put a piece of graph paper in a negative carrier and projected that on to the baseboard and measured the distance between the lines. If the top and bottom distances were the same and the left and right side distances were the same, I considered it aligned. I put a negative in to check and found all four corners and the middle in focus.

Dave

-- Dave Willis (willisd@medicine.wustl.edu), August 30, 2001.


The Peak focuser (model 2000, which allows to check the focus in the corners) is, in my opinion, a simple and efficient way of aligning enlargers. The enlarger is properly aligned if the grain of the emulsion is simultaneously sharp in the four corners. The advantage of this method is that it relies directly on the most important criteria of alignment: sharpness throughout the entire surface of the negative. Moreover, it also gives information on the quality of the enlarging lens at the chosen working aperture; field curvature is, for instance, evident if the four corners, on the one hand, and the center, on the other hand, are not simultaneously sharp. I have, for instance, two samples of the same enlarging lens (105 mm rodagon) and I discovered, using the Peak focuser, that they were quite different, wide open, in term of field curvature. Another advantage of this solution is that it does not involve an additional gadget since a grain focuser is anyhow essential. One should lastly note that the Peak (all metal) is a much nicer object than the usual all plastic grain focusers.

regards, Matthieu

-- Matthieu LS (lstrauss@infobiogen.fr), August 31, 2001.


Another contributor to these pages describes a procedure using two mirrors in this document:

http://members.rpa.net/~choffman/darkmeasure.htm

I haven't made the mirror with the hole in it yet but it looks like the method should work quite well.

Cheers,

Duane

-- Duane k (dkucheran@creo.com), August 31, 2001.


Hi, I have had good luck with the laser method. The real surprise was finding large differences between easels. Some of these were greater than any enlarger alignment problems. Don't forget to check these rascals Dick

-- Dick Bennett (brboy@pilot.infi.net), August 31, 2001.


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