anyone experienced with 23c enlargers?

[phildo]

it's what i've been using in my school's darkroom, so i picked one up for myself, though the head is a bit different. instead of using the condenser head, i opted to use the dichroic head so i could dial in the yellow and magenta instead of using multigrade filters...

anyways, i was trying to set up some printing for 6x6 and i was getting a lot of light falloff in the corners, making printing troublesome. i tried several different things like taking out the condenser lens and replacing it with the diffuser assembly, and changing the distance from the condenser or diffuser to the negative, etc. and i'm still getting a lot of falloff in the corners. is there an optimal setup for this configuration that i'm not aware of?

what height should the diffuser be set at when it's in? i imagine height won't make as big of a difference as opposed to when the condenser is in, but i'm not really sure.

 

[ann]

the dichroic head needs to set right on the negative stage. it is not moved with regard to the negative size as you would a condensor head.
the whole condenser section needs to be removed and replaced with the dichroic head

 

[Bruce Appel]

Ann is right.

 

[dschneller]

If you swapped out the condenser and put in the diffuser you should also change the light source assembly (swapping the cone shape for the honeycomb thingy). Put the condenser back in and if you look behind the dichro head on the right hand side you will see the head adjustment Ann and Bruce are referring to. It should be clearly marked so that you may set the head height to the format you are wanting to print. Also, if you are trying to print 6x6 you should be using a lens around 90mm.

 

[ann]

when you change out to the dichroic head you had to remove everything down to the negative stage, that will include any condenor lens.

also the dichroic head sits on top of the negative stage, and the format adjustments are not in play here. they are used only for moving a condenor light source to make the negative format.

then, the correct focal length for each format should be used

 

[voceumana]

Make sure you're using a 75 or 80 mm enlarging lens for 6x6.

Charlie

 

[ann]

there is one other item to check ; depending on the age of your enlarger.

In the old days enlargers had a sliding drawer above the lens and below the focusing bellows. One could slide a filter in there and the slide it under the negative and above the lens. There may be a metal bar, about an inch long attached to the frame holder, which moves the drawer in and out. This bar is put in place with a threaded base and so if that has been removed with the drawer engaged with out a filter in place it will create a cirlce effect, or an uneven cirlce, depending on the postion of the holder.

 

[phildo]

there is one other item to check ; depending on the age of your enlarger.

In the old days enlargers had a sliding drawer above the lens and below the focusing bellows. One could slide a filter in there and the slide it under the negative and above the lens. There may be a metal bar, about an inch long attached to the frame holder, which moves the drawer in and out. This bar is put in place with a threaded base and so if that has been removed with the drawer engaged with out a filter in place it will create a cirlce effect, or an uneven cirlce, depending on the postion of the holder.

i've definately got an older 23c. it's blue. anyways...

i checked the filter drawer betwixt the negative stage and lens and it's got nothing in it, so it's not a filter frame that's causing the vignetting.

you said earlier that the whole condenser section needs to be removed, but i don't see how i would do this without making a sketch so i can remember how to put it back together later.

i have a dichro 23dga colorhead and it fits right on top of the condenser lamphouse once i remove the bulb that secures to the lamphouse with a screw.

 

[Gay Larson]

I have 2 23c's. one I replaced the condeser with a diffused light. I took the entire condenser out to put in the new light source. Be sure you have the right lens for the 6X6 also. I found that if I try to use the lens for 35mm on medium format I get the fall off you are describing.

 

[ann]

there is a bar holding the condensor head in place, the bar has a counter pin on the end. remove the counter pin. pull out the bar and the whole head lifts off.
just repeat going the other way to put the other head on.

drop the head inplace, insert the bar and replace the counter pin, quick and simple.

 

[BWGirl]

Hey phildo!

Here's a link to a manual for the thing. It's free & when I got my 23c, I printed it out, put it in a notebook & it has served me well ever since!

Dead Link Removed

 

[phildo]

hahaha, okay, so i had the enlarger set up correctly.

my problem was the lenses, which was a beseler "beselar." what a flaming piece of crap lens. i could focus light better with bubbles i blow out of my spit. time to hunt for some componons or something

thanks for all the help, everyone.