Enlarger alignment of c700

[Fall]

Hello all,

I have an omega c700 and during my last printing session I could not get my print straight. The projected image was crooked, and I'm pretty sure this is an alignment issue. I have searched and searched, but all the information one the topic is very confusing, and/ or expensive. It would be very nice if some one could help me out. I don't see how this could be this hard, and how there is not more info on this since there are so many photographers pre digital. Any help is appreciated. Thank you.

 

[Ronald Moravec]

C700 is an enlarger without alignment controls so we have to resort to crude measures.

level the base with shims, cardboard, paper, or tape. Mark one end of the level for right and rear direction in case it is not perfect.

now shim the negative stage so it levels with the weight of the head on it by using shims under the column base. Use a piece of glass extending the neg stage for a place to put level.
Alternatively use some tape under the neg carrier,

Now you have to align the lens board. Put the level across the lens. This does not always work. Better to use the Peak or Omega grain focuser along the edges. Must be the long mirror model to see edges. Short model is only good in the center.

If the baseboard is warped or sagged down, forget it. Mine was. Make a new base or buy a better enlarger. All consumer grade things are made cheaply.

 

[RobC]

One of these is the easiest to use and allows you to get the lens perpendicular to the negative which is the most critical.

http://www.versalab.com/server/photo/products/parallel.htm

The cheapest option is to take a piece of fully exposed and developed film leader which is essentilly black it's so dense. Then with a ruler and a pin, scratch a cross on the emulsion side from corner to corner. Then place in neg holder using glass top and bottom and project onto easel. Then with a loupe which you can see into corners, you can see the rough edge of the scratched lines in each corner.
Adjust with shims until corners are equally sharp (or unsharp). Corners are usually less sharp than center.

Its a bit tricky becasue you don't know where the error is, lens to neg stage or the lens to easel stage. But it will confirm or disprove your fears.

 

[Fall]

Ian,

1st. What I mean by crookedness is when the image is projected I can take a test sheet 8x10 paper and am unable to have it straight. I will include a screen shot of a diagram of what I mean in the attachments. I’ll put a number for when I am describing each diagram. Diagram 1. In the diagram it does appear that just tilting the paper on the base would solve this, but when the paper is moved the other size becomes crooked as well. I have determined that one side of the projected image is larger then the other. See if I adjust the paper like so Diagram 2. The projection over the paper will now look like this Diagram 3. I don't understand this phenomenon, and if you need any more clarification on that point let me know.





2nd. The carrier is for the enlarger. I purchased the enlarger and it still had the box with it, and the negative carrier looks identical to an image search of the enlarger.



I really appreciate your help with the matter, and I hope I can figure this out.

 

[RobC]

If the head on this enlarger can be tilted to project on the wall then make sure the tilt is set to zero.

 

[Paul Howell]

My guess is the enlarger head is tilled in 2 directions . You need to see if can shim the paper easel in 2 directions until the image is square. There were enlargers made with a tillable head so that out of perspective buildings could be printed with a correct perspective. When adjusted the full image would not be square so you cropped not so square boarders were cropped out.

If you are seeing this much distortion, you might to make the head apart and see if see what is bent and see if you can straighten it.

 

[RobC]

following pdf shows some alignment at back of column. Which head do you have with it, dichroic colour head or condensor head?

http://debejyo.com/photography/docs/omega_c700.pdf

page 4, number 15 on diagram.

 

[Paul Howell]

Did you see any text with instructions on how to use the screws to align the head? Seems just 2 screws, ought work for both heads. If the bracket that hold the lever and hinge is bent or if the negative stage is twisted, may not be enough travel in the adjustment screws to bring the head back into alignment.

 

[RobC]

Also if the negative stage has adjustable cropping blades, are they set correctly? i.e. each blade is parallel to its opposite blade.

If you can put a neg in carrier which has a straight line along one edge, then does that edge project on a slope or horizontal ? i.e. is it the neg which is being cropped into that shape or is it being projected into that shape?