Omega DII Light Output

[Ohio Sean]

Hi, Folks,

I seem to be having trouble with light output on an Omega DII I recently picked up and wonder if maybe I've got it setup wrong. I'm moving from a B22 perspective where I had too much light and always had to work with the lens stopped down to F22, to the DII needing to be wide open at F5.6-8 and still having exposures run 40+ seconds.

The enlarger itself is an Omega DII, but it has a D2V variable condenser. The standard condenser that came with it is the larger 6" variety. I'm using an 80mm Nikkor lens mounted to the flat lens board with 6X6 negatives and making 8x10 prints. I keep the variable condenser in its lowest level (looks like its laying in a hole inside the house). I have aligned the enlarger since bringing it home. The enlarger came with a burnt out 150W bulb, but everything I read says the standard is 75W (including the side of the lamp house) so that's what I replaced it with (PH211 enlarger bulb from B&H). I know there had been different sized condensers available and wonder if 75 watt bulbs were for the 4" condenser but I have not read that in any literature. In fact, I think KHB lists a 250W bulb you might use, too. Should I just up this to 150W?

What determines the bulb wattage? I can move up to 150W but feel like something else is wrong here. Thoughts on this?

Also--how small can you expect to print with this enlarger? I thought I should be able to print on 5X7 but simply cannot get down that small. I'm aware that there is a bellows attachment available for smaller prints, but really would have thought this enlarger could handle 5X7 without it, so I feel like something is off there, too. To save money, my work flow uses 5X7 paper for tests and family photos, then up to 8X10, 11X14 for the better photos.

Thanks!
Sean

 

[MattKing]

On the size issue, have you tried raising the easel by putting something under it?
Or is the problem that you cannot focus the enlarger when the image size is 5x7?

 

[Paul Howell]

I have a D3, other than the focusing rails that I np long use as I don't have lens that match the rails my set up is the same. I print negatives that I've scaled to grade 2 negatives, with 50mm usually a Wollensake a 8X10 runs around 12 to 15 seconds with a 75 watt or 1200 Lumens LED. My older negatives from the 60s and early 70 are high contrast for newspaper reproduction of the day some take a very long time, in the range you are talking about some even longer. With those I print with a 1600 lumens LED which cut the time in half, print with grade 2 filter. If you have plate on the housing it clearly states 75 watt bulb, but I've used a 150watt bulb in the past but find the LED works as well without the heat. Be careful about allowing the condenser to get hot and having it crack. A piece of heating absorbing glass might help. Other concernif using a glassless negative carrier and have negatives buckle. I would not use a 250, but if you must allow for cool down time.

Don't know why you cant focus a 5X7 with an 80mm lens, I have no trouble with 75 or 80mm.

 

[Pieter12]

You can use a longer focal length lens, such as a 135mm or 150mm for smaller prints. The bonus is you'll be using the sweet spot of the lens.

 

[ic-racer]

The DII brochure lists just 75W lamp. I don't know if that original "Dyna-Thermal" lamphouse is rated for the 150 or 250W lamps.
If you are at the limit of your bellows extension, try the 2 3/4" cone to get to lower magnification. Or use a shorter focal length lens (like 60mm) that won't use up all your bellows.

 

[Pieter12]

The lamphouse looks pretty much the same as the D5. I used a 150W halogen lamp in mine before switching to LED. It was bright enough that I had to use ND filters for 8x10 prints.

 

[Ohio Sean]

Matt King and others that suggested moving the baseboard/ easel into a higher position--Thanks for reminding me. I can't believe I forgot about just raising the easel! You switch enlargers on a guy and he forgets everything--as if he's never used one before!

Paul Howell--good info about low vs. high contrast negs and how much time they need. For your 50mm lens exposures lasting 12-15 seconds--what aperture are you using? This is my biggest issue. While I, too, can get exposures in the 12-15 second range, I am being forced to use larger apertures to achieve this. I really want to get the lens stopped down to 11 so as to achieve the sharpest abilities the lens has to offer. As it happens, I'm always at 5.6 or 8. 8 is okay, but not better than 11. And honestly--I'd just like to have more flexibility and access to more stops if that makes sense.

As for higher wattage bulbs--the previous owner was apparently using a 150 watt since that's what it came with--but that doesn't mean he was correct in doing so. I do use a piece of heat absorbing glass placed in the highest slot in the variable condenser above ALL lenses/glass. One slot lower is where I place my filters. So far, with the 75 watt bulb, nothing seems to be getting warm so I think I can handle the 150W, but feel like I shouldn't have to if the thing was designed for 75. If anyone else comes up with ideas, let me know.

For those using LEDs: how do you determine if the color is correct?

Right now I'm in the process of 3D printing lens mounts in different sizes. If anyone else is into 3D printing let me know if you have a sharable file for a 6X9 120 roll negative carrier. I'm fine using the sandwich type. I have been able to find a 6X7 but the file doesn't seem easily modified so may have to be modeled again.

Thanks again, folks!

 

[Paul Howell]

I generally use F8 to 11, in the past I've used 150 watt bulb, you can have a glass shop cut a square of heat absorbing glass to fit in the variable condenser housing in the top or middle position to protect the top condenser from overheating. Currently I use a GE 1600 Lum LED, seems to work with 1 1/2 to 2 1/2 filters I use for my older high contrast negative. The rest of the time a 800 or 1200 Lum GE LED seems to work as my negatives are scaled to grade 2. If I to print grade 3 1/2 or 4 I will use a 75mm watt enlarging bulb. And I don't split print. BTW I forgot to ask, you have both the top and bottom condensers? If you don't have the top condenser just the bottom you are going to print really slow, the variable condenser without the top condenser is how you print 4X5.

 

[Ohio Sean]

Paul--right--I have both condensers--the 6" stationary set in the spun aluminum cylinder plus the one that moves between the three positions depending on the enlarging lens used. I have that one in the lowest position for use with the 80mm lens.

Thansk for the info on the f stops. I can print in f8. F11 takes quite a bit longer.

I think my surprise comes from using the B22 for so long where printing with f22 was pretty much a necessity!

 

[Pieter12]

I may be totally wrong here, since I have no first-hand knowledge of the D-II enlarger (http://www.khbphotografix.com/omega/Enlargers/DII.htm). From what I read on the KHB Omega enlarger site, the D-II was not made with the variable condenser head, but the D-2 was later available with it (http://www.khbphotografix.com/omega/Enlargers/D2.htm). On my D-5 (with the variable condenser head), there are 3 condenser lenses: the variable one under the lamp house, and 2 condensers in the aluminum housing above the negative carrier (one at the top, one on the bottom). Could your D-II have been modified to take the variable condenser and might it be missing one of the condensers in the housing below?

 

[Zathras]

Sean, another thing you might want to check for is is the presence of another heat absorbing glass mounted in the lamp housing. I remember a D2 in the darkroom at a local community college that was very dim. This enlarger had a heat absorbing glass installed in the lamp housing and it had gotten very dirty. Once the glass was removed and cleaned, there was plenty of light available.

 

[Ohio Sean]

Hi, Pieter12--I do understand what you're saying. I have an old "lift to lock" DII enlarger body which later had a D2V variable condenser put in place of the original housing. I have, exactly as you described, 2 condensers in the aluminum cylinder with the variable condenser above. For an 80mm lens I place the moveable condenser in the lowest position (essentially laying in a hole as the illustration in the housing shows).

Zathras--good point. I'll have a look above the D2V just to be certain. And hey--wouldn't hurt to give all the class a good cleaning!