New enlarger and lots of broken glass...what next?

[kcc008]

I am relatively new to analog photography, I've been working in digital for several years and was bitten by the analog bug a few months ago. Since then I have acquired a 4x5 monorail and more recently an Elwood 5x7 enlarger. The enlarger is missing the diffusion glass, but is otherwise in good shape.

I read on a forum post somewhere that using a standard tungsten bulb with an "extender" (a device that screws into a light socket and supplies two power outlets) puts the bulb in the correct position for the Elwood's reflector to work best. I tried this today with a 200W bulb and no diffusion to see what kind of light spread the reflector would produce. The heat from the bulb broke two pieces of glass in the negative carrier and melted the negative.

Most of the forum posts that I have read suggest that the heat absorbing glass is optional and several people seem to have good results using standard window glass modified to work as a diffuser.

Is using a 200 watt bulb unreasonable or unnecessary? Does anyone have suggestions for a low cost solution to this problem? The proper heat absorbing glass that I have seen for sale that would be an appropriate size for the Elwood would cost almost as much as a cold light head.

 

[richard ide]

Try a 100w opal enlarger bulb (PH211?). I bought heat absorbing glass from a local glass supplier. IIRC a 16" x 16" piece cost me less than $100. You must have had the lamp on for a long time for the heat to build up enough to do that damage. A diffuser is a necessity. A sheet of matte surface drawing film between 2 sheets of window glass makes a good one.

 

[epatsellis]

first, do you have the manual? if not, head over to camera eccentrics website and download the pdf, there's lots of good info in the manual regarding setup and such.

The bulb holder is adjustable, and if you use a longer bulb, the # evades me at the moment, you can adjust the lampholder while viewing the light dome from the open end, you can judge when it's in the right position easily.

 

[kcc008]

Thanks for all of the great info. I found the manual and it was very helpful.

The manual suggests that any bulb smaller than 2.87 inches in diameter will not produce even illumination. The PH211 has a diameter of 2.6 inches; any ideas where I can get a larger diameter bulb?

 

[epatsellis]

I think I used a 300w bulb from Ace, and added some diffuser to the stack of glass in the head.


erie

 

[ic-racer]

I am sorry to hear about your carrier breaking. I have had to replace the glass on a used enlarger just from little scratches anyway, so that should not be too much of a stetback. Let us know if you need a glass source.

 

[Jim Jones]

I'd check the eveness of illumination on the baseboard at typical lens apertures and enlarging ratios before worrying about bulb diameter. My diffusion Elwood had illumination drop-off at the edges, but grinding the center of a sheet of glass above the diffuser cured this.

 

[outwest]

I used to have a 5x7 Solar that used a huge 212 bulb. I'm sure it wasn't 300 watts as that would have made it an oven. I just looked in the back of the cabinet to see if I still had some kicking around, but all I found were 5 211's. Sorry.