Exposure times of some enlargers are way up??

Hello,

My latest quesiton was about a piece of broken bulb / lamp still sitting in the cracked-ceramic-holder (I think I have found a donate unit on a local market, waiting for it to arrive).
Last weekend I notice another problem, the exposure times on one of the enlargers is way up compare to the other enlargers. My questions; what could be the cause and how can i fix this?
I thought a bulb/lamp (halogen) is good or broken? Can it also be less powerfull??
Could it be a faulty transformer??

Hope I don't need to find another unit

aca said:

Last weekend I notice another problem, the exposure times on one of the enlargers is way up compare to the other enlargers. My questions; what could be the cause and how can i fix this?

Click to expand...

If the enlarger has a filter drawer, check that it doesn't have an extra filter in it. (yes, BTDT)
It is possible for a lamp to age differently than the others, but they'll usually blow instead of getting less bright.

Depends on the condenser or diffuser, the type of bulb, age of the bulb, bulb voltage, ...

A lot of halogen bulbs use a common socket. You could have the wrong bulb in place. You need to know the voltage and wattage. There should be a three letter code for the bulb.

Tx again,

I am going to the darkroom this evening and will check the drawer.

@George Nova Scotia : where can i find the 3 letter code? on the socket??

@Sirius Glass, the condenser, do you mean this condensing lens? and what should I do with these??


I have this bulb to use:

aca said:

@Sirius Glass, the condenser, do you mean this condensing lens? and what should I do with these??

Click to expand...

Leave the condenser alone, it could change the exposure time. Check to see if you have the right bulb in the enlarger.

Sirius Glass said:

Leave the condenser alone, it could change the exposure time. Check to see if you have the right bulb in the enlarger.

Click to expand...

Ok, I will leave the condenser alone. How do I check if I have the right bulb?? George said something about a 3 letter code, where on the unit/ enlarger can I find this code??

In another thread I read a halogen lamp will lose his power gradually. I need to buy a brand new bulb to be sure and check this. There are 3 bulbs in package, but I am not sure if these are used "and not strong enough anymore"

I will keep you up to date

Check as well to be sure that the lens is both clean (both top and bottom) and free of haze. Also check that the aperture is working properly - not stuck at a smaller opening.

Ok, just got back from the darkroom and did a couple of checks, but not happy with the results. Now I am home again I realize I test with the color buttons to get the contrasts and not with physical filters. Could the color unit be a bit off with the filter grades???