Enlarger Lamps

[70to210mmf4]

The lamp in my enlarger has blown and I need to replace it. Are they all the same? Can I just get any one I find on ebay or do I need to get one specific to my enlarger? I have a Durst.

 

[ac12]

The lamp in my enlarger has blown and I need to replace it. Are they all the same? Can I just get any one I find on ebay or do I need to get one specific to my enlarger? I have a Durst.

WHICH model?

Some enlargers are VERY specific, others more forgiving of using alternate bulb.
Some almost require alternate bulbs, as the original bulbs are no longer manufactured.

 

[70to210mmf4]

It's a Durst RS 35. The manual doesn't say anything about the type of bulb I need. I found this useful webpage, but it doesn't say anything about that model.
Replacement Light Bulbs-Cross Reference Guide D

An ordinary screw type light bulb fits in the socket, so I just went ahead and got this cheap Paterson bulb. I hope it will be ok for my enlarger.
It says this:
The Enlarger Lamp 230/240v 75w from Paterson is suitable for any enlarger that takes standard ES screw fitting lamps.
Paterson Enlarger Lamp 230/240v 75w 31293036629 | eBay

 

[ac12]

Where are you located?
If in the US, a PH-211 75w bulb should work.
Although if you are looking at that 230v Paterson bulb, it does not seem that you are in the US.

The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

I find it odd that it would be named RS 35 when it can handle 70x70 film.

 

[Derrel]

well, I would try the Patterson bulb and see how it works for you.

 

[70to210mmf4]

Where are you located?
If in the US, a PH-211 75w bulb should work.
Although if you are looking at that 230v Paterson bulb, it does not seem that you are in the US.

The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

I find it odd that it would be named RS 35 when it can handle 70x70 film.

I'm in Australia. I think 70x70 is the size of the colour filters it accepts, not the size of the negatives.

 

[70to210mmf4]

well, I would try the Patterson bulb and see how it works for you.

Yes I will try it. I'm just worried that I'm going to blow something up or electrocute myself.

 

[70to210mmf4]

Where are you located?
The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

That's good to know. The manual does say to twist the bulb to get it even, but I hadn't thought of moving it up and down too. Thanks.

 

[ac12]

The RS-35 looks somewhat like the M600. So what follows is based on my M600.

The bulb screws into the M600 from the top.
Below the head, there is a tube-like assembly where the power cord goes into the head. The top of this assembly is where you screw the bulb into.
Twisting that tube-assembly lets me push/pull, to adjust the vertical position of the bulb in the head. The tube assembly is friction fit/not threaded, twisting it just makes it easier for me to move it up/down.

If the manual says to twist it. The assembly might be threaded, rather than friction.

The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

The PH-211 is a 120v bulb.
Worst case, look for a 75 watt, WHITE bulb, without any printing on the side.

Although if it prints too short, you might look for a lower wattage bulb. A 75 watt bulb in my M600 results in an exposure less than 10 seconds, which is almost too short. I wanted to get a 40 watt bulb, but they don't make a photo bulb that low.

 

[ac12]

Where are you located?
If in the US, a PH-211 75w bulb should work.
Although if you are looking at that 230v Paterson bulb, it does not seem that you are in the US.

The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

I find it odd that it would be named RS 35 when it can handle 70x70 film.

I'm in Australia. I think 70x70 is the size of the colour filters it accepts, not the size of the negatives.

Yes, I looked at a pic of the enlarger, and the 70x70 is the size of the color filter, not the negative.

 

[70to210mmf4]

The RS-35 looks somewhat like the M600. So what follows is based on my M600.

The bulb screws into the M600 from the top.
Below the head, there is a tube-like assembly where the power cord goes into the head. The top of this assembly is where you screw the bulb into.
Twisting that tube-assembly lets me push/pull, to adjust the vertical position of the bulb in the head. The tube assembly is friction fit/not threaded, twisting it just makes it easier for me to move it up/down.

If the manual says to twist it. The assembly might be threaded, rather than friction.

View attachment 179274

The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

The PH-211 is a 120v bulb.
Worst case, look for a 75 watt, WHITE bulb, without any printing on the side.

Although if it prints too short, you might look for a lower wattage bulb. A 75 watt bulb in my M600 results in an exposure less than 10 seconds, which is almost too short. I wanted to get a 40 watt bulb, but they don't make a photo bulb that low.

The bulb that blew out was one that came with the enlarger. It's clear and has RADIO ARGON 130/60 printed on the base. Does that mean it's 60 watts? On the two test strips I managed to make before the bulb went out, 2 seconds at f/8 made the print WAY too dark which I think means either the globe was too bright or I stuffed up something myself (which is very very likely).

 

[ac12]

The RS-35 looks somewhat like the M600. So what follows is based on my M600.

The bulb screws into the M600 from the top.
Below the head, there is a tube-like assembly where the power cord goes into the head. The top of this assembly is where you screw the bulb into.
Twisting that tube-assembly lets me push/pull, to adjust the vertical position of the bulb in the head. The tube assembly is friction fit/not threaded, twisting it just makes it easier for me to move it up/down.

If the manual says to twist it. The assembly might be threaded, rather than friction.

View attachment 179274

The Durst illuminates from the side of the bulb, so you have to adjust the vertical position of the bulb to give you even illumination on the baseboard.

The PH-211 is a 120v bulb.
Worst case, look for a 75 watt, WHITE bulb, without any printing on the side.

Although if it prints too short, you might look for a lower wattage bulb. A 75 watt bulb in my M600 results in an exposure less than 10 seconds, which is almost too short. I wanted to get a 40 watt bulb, but they don't make a photo bulb that low.

The bulb that blew out was one that came with the enlarger. It's clear and has RADIO ARGON 130/60 printed on the base. Does that mean it's 60 watts? On the two test strips I managed to make before the bulb went out, 2 seconds at f/8 made the print WAY too dark which I think means either the globe was too bright or I stuffed up something myself (which is very very likely).

I don't know how to read the printing.
I hope it is NOT 130 watts. That is way too bright.
Maybe it is read as 130 volts / 60 watts

My M600 started with a 150 watt bulb, as per the manual. But that was quickly changed to the dimmer 75 watt bulb. And even that was almost too bright.

The Durst is a bright enlarger.
2 seconds is way too short an exposure time. I would target 10-20 seconds.
I think you should look for a WHITE 40 watt bulb, of about the same physical size as the 60 watt bulb.
The alternative is to use the 75 watt bulb, and put a 2 stop Neutral Density filter on the lens.

 

[IanG]

According to Durst themselves the RS/35 uses a 60 watt clear household bulb. That will vary in voltage depending on the country and Australia like the UK is 230/240v 50Hz. Tfitting may differ in some countries. Other Duurst enlargers are listed as taking Opal enlarger lamps that indicated the RS/35 has a built in diffuser.

Just to clear up the filter size is quite different to the format, the RS/35 was designed for sub-miniature to 35mm negatives so as well as 35mm and Instamatic negatives masks there were also masks for various 8mm and 16mm films. The was also a copy camera attachment.

It wasn't uncommon for older enlargers to use clear bulbs, I have a very early Gnome enlarger that uses a 12v car head light bulb and a transformer, and had a glass diffuser (lost/broken) which I'll replace soon.

Ian

 

[IanG]

Ian

 

[ac12]

Thanks Ian,
A standard clear bulb is sooo much easier to find than a opal/frosted photo bulb.