Elwood 8x10 Questions and Photos

[willwilson]

I finally took the plunge. This thing was a great deal and impossible to pass up. It came complete with negative carrier and the hard to find original diffusion glass. I have included some photos for anyone that wondered what these things look like, as I didn't come across many in my own research. I am not sure of the model number, perhaps C-2? Anybody?

Photos are: Elwood Enlarger, Negative Stage with ?heat absorbing? glass, glass negative carrier, and diffusion glass.

It came with a 300mm lens and will print an 8x10 negative with the easel resting on the lower frame to 22x28. This is max extension and at this extension the top of the light source is 98" from the floor, only 92" high for 20x24. This thing is a tank, all metal except for lens stage and lens stage guide bars, but not as heavy as you would think, maybe 150-200lbs. It can bend backwards for horizontal use as well.

There is another very helpful thread here:
http://www.largeformatphotography.in...ead.php?t=9579

I do have some questions for the Elwood users out there...

1) I bought a PS30 300watt frosted bulb today at light bulb depot, http://www.lightbulbdepot.com/product.asp?prod=01242B. It seems to be the same type of bulb recommended for this enlarger except it is frosted instead of white. I did some brief testing this evening and there appears to be a a center hot spot. Do you think this is normal or due to the bulb being frosted instead of white? It has a schneider 300mm 4.5 Xenar on it now. It has a hot spot stopped down to f16 or more as well. Should I splurge for a PH301 from here, https://www.interlight.biz/light-bulb/PH/301, for $37.00 instead? Anybody tried the PH302 (500 Watt) or equivalent in there 8x10 Elwood? Aristo is not in my budget right now.

2) What wide angle enlarger lens should I be looking for? Would a Fujinon 240mm A cover 8x10 and work as an enlarging lens? Is light fall-off a problem with wide angle 8x10 enlarging lens.

Thanks! -=Will

[Chuck Pere]

Mine didn't include the internal glass pieces so I'm not sure if the diffusion glass is the kind with a heavier center spot gradually decreasing to the edges. If yours is just a piece with the same diffusion across it that may be the problem. There may even be somewhat of a hot spot with the proper diffusion glass.

I use a 240 lens with no problems I can see. But I don't enlarge many 8x10's so may be fooling myself. I would think that any major brand 240 enlarging lens should work fine.

I have some jpegs of a parts list. PM me your email address if you are interested.

Oh, nice shot of that negative carrier.

[ic-racer]

I spent some time fine-tuning my light source to get a nice even field with my Aristo. You may have to experiment a little. One thing to try is a 'center filter.' Here is one I made with an inkjet printer. (Don't think because you go with an Aristo you will automatically get even illumination ) http://www.largeformatphotography.in...ad.php?t=40384
http://www.largeformatphotography.in...6&postcount=29


Is there some reason you don't want to use the 300mm? Schneider publishes the light fallof at various apertures for the current lenses, but no data on the older ones. So, I can't say if needing to go all the way to f16 to get an even field is normal or not. BTW I usually print at f16 with my 300mm Rodenstock.

Good luck. Fantastic enlarger!

[ic-racer]

Based on what you posted, your image size seems smaller than I would think. I checked my 300mm lens and to get a 20" wide projection of the 10" side of an 8x10 negative, the negative carrier is 53" from the baseboard. Are those the same numbers you can measure?

[Peter De Smidt]

I used to have one of these. It's a table top "autofocus" enlarger. Mine came with a 250mm Ektanon lens. I might even still have the lens, and I probably have a spare negative carrier. Anyway, I uses an Aristo 1212 with mine. I tried once with a 300 watt bulb with no diffusion glass and the heat warped the negative. Thus, do be careful and run a test with a non-important negative.

[willwilson]

-update-

Enlarger is set-up and is working great with a 10" Ektanon, the original head, and 300 watt frosted bulb. No problems with heat. Falloff is no longer an issue now that I am using the 10" Ektanon.

Also found a nifty formula for enlargement magnification:

D/F - 2 = M

D = Distance from negative to baseboard
F = focal length
M = Magnification

[Jim Noel]

I found the original diffusion insufficient for preventing hot spots. Additional diffusion with opal glass took care of the problem. I don't know of a current source for opal glass, but additional ground glass, or Kodak Diffusion Material should do the trick.

[Peter De Smidt]

Glad to hear it's working well.

[EdWorkman]

I use a Fuji 180 enlarging lens and it seems to work well for 8x10. Mostly I print from 6x17 onto 8 or 10 by up to 42 inches, the limit of my trays [and arms]. Yes the cosine 4th law seems to require some dodging at times. I'm [still] over 6 ft tall so I set my tabletops and sink somewhat high to save my back. So I re-frambulated the wall support for the Beseler in order to let the enlarger head pass up between the roof trusses in order to get enough magnification, and also drop the tabletop a coupla feet to get to the extremes- then it's a matter of reaching the focus knob and eyesight. The Fuji has no clickstops but I've learned to work around that as well, and I use Rosco light filters for VC. I consider myself a proud member of the unwashed masses

[aduncanson]

Also found a nifty formula for enlargement magnification:

D/F - 2 = M

D = Distance from negative to baseboard
F = focal length
M = Magnification

This formula does not work too well for smaller reproduction ratios. It looks like it has a error of 10% at 3:1 and 100% at 1:1.

I would suggest m = f/(d-f) where d is the distance from the lens to the negative.

The only problem is that the effective location of the lens (its rear nodal point) is unknown for any practical enlarging lens. If precision is required then set up the enlarger to project a negative at 1:1 on the baseboard (some trial & error will be required) and measure down two focal lengths from the negative and make a mark on some part of the enlarger that is rigidly attached to the lens. That will be the effective location of the lens for measuring the "d" needed to calculate an unknown magnification in the future.