New Enlarger - Strange ring around image

[teekoh]

Hi,

I recently acquired a Durst M605 Colour enlarger and when I turned it on I noticed a weird ring shape being shown. I've attached the image. Can someone tell me if there is something wrong with the enlarger?

Thanks.

 

[MattKing]

Welcome to APUG!

When you adjust the focus, does the image improve?

Is the head turned slightly from the vertical?

 

[teekoh]

Thanks Matt. When I have a negative in the carrier and I adjust the focus the image seems to focus without any issues. I also check and the head is set to 0 degrees. I noticed the top half of the head moves when I insert the negative carrier and there is significant light leak on one side of the carrier. It doesn't seem to sit flush.

I've attached another image to show the weird square and ring.

 

[MattKing]

There may be something astray in the light path.

It has been years since I used a Durst M6xx series enlarger, and even longer since I had one opened up.

You probably need to attract the attention of one of the Durst users here on APUG. For future reference, it would probably help if you had included Durst M605 in the thread title. No one would mind if you started another thread for that purpose, and linked to it here.

Have you checked the manual?: http://www.jollinger.com/photo/cam-coll/manuals/enlargers/durst/Durst_M605.pdf

 

[teekoh]

Thanks Matt I'll take a look at the manual and repost with a different title.

 

[Mr Bill]

teekoh, if you can twist your body enough to get your eye up to the enlarger lens, you'll be able to look inside and likely see what the problem is.

It'll be bright, so you might want to use an extra-dense negative, or neutral density filtration, or even sunglasses. If it's too bright for you, don't persist. (If your eye can't focus, rack the enlarger lens in a bit, as though making a very large print.)

I've never used one of those enlargers, but my guess is that a light baffle or similar is not fully seated. Good luck.

 

[MattKing]

As it us a Durst, it depends on the light being reflected by a mirror. The mirror itself may be damaged or out of position.

 

[teekoh]

I took a look inside and noticed the square is in fact created by the light baffle which was confirmed by moving it up and down. The strange circle is actually a silhouette of the piece of metal underneath the negative carrier and above the light baffles. I have no idea what the purpose of that round metal piece is for however. It's held in place by several screws so I'm guessing it serves a purpose somehow. I'm going to see if I can locate the mirror and figure whether it has been dislodged.

 

[MattKing]

I think we may have a terminology problem.

I don't know of any light "baffles" that one might find below the negative holder.

There should be a bellows, a lens stage, a lens panel and a lens below the negative holder. As you adjust the focus, the bellows stretches/compresses and the lens stage, panel and lens move up and down.

 

[Cybertrash]

My M605 does the same thing (the circle anyway), I figured that's just the way things are with these pieces. Doesn't bother me since the circle always fall outside the paper when I'm printing, and it doesn't seem to fog the paper either.

 

[teekoh]

Ah sorry mixed up my terminology by baffles I meant bellows. I took the head apart, took the bulb out, checked the mirrors, and made sure the head was aligned when I screwed the head back on. I couldn't find anything noticeably wrong with it. I did find out that the bellows attach to the circular metal piece which is also responsible for the weird circle of light. The bellows in turn seem to be creating the square lighted areas. Both shift in and out of focus as I adjust the focus knob.

Hmm thanks for the insight Cybertrash. I would love to hear from other M605 owners to see if they experience the same thing.

 

[Alex Muir]

Could the circle be caused by either the lens panel not being fully seated, or the lens not being seated in the panel? The lens panel is usually secured by a single screw and a lip on the casting at the bottom of the bellows. Try removing and re-seating it. If you have an Ilford Multigrade filter holder attached around the lens, check that also to ensure there is no light leak where it attaches. Since the circle is outwith your print area, it shouldn't be a problem, but it would be nice to get rid of it. Alex


Sent from my iPhone using Tapatalk 2

 

[Ian Grant]

I'm inclined to agree with Alex. I've been using Durst enlargers for over 40 years and haven't seen this.

Ian

 

[AgX]

To get to the lens panel light first has to pass the film stage. And there is only one rectangular opening (for the film frame). Furthermore the film stage is protruding beyond the casing.

 

[ic-racer]

Could you post a picture of the inside of the bellows looking up with the enlarge lamp off? I'd just ignore the projected ring of light if nothing is loose or falling apart or assembled incorrectly.

 

[teekoh]

Hi Alex, thanks for the suggestions I tried both but still no changes unfortunately. I've attached a photo of the inside of the bellows and as you can see the circle shape is caused by the bellows holder. I'm just not sure how that is happening.

 

[Ian Grant]

Compare the two images and you've found where the light's coming from.

It won't be there when the correct Durst negative carrier is inserted as that masks down tightly to the 6x6 format.

Ian

 

[AgX]

If I'm right that moulded part is not the format insert , but the film stage itself. And this is larger than the condensor housing.
How could light pass that stage and project an image of the contour of the bellows plate?

Could it be that the masking plates are retracted too much so that light spills through their guides?

 

[Ian Grant]

If I'm right that moulded part is not the format insert , but the film stage itself. And this is larger than the condensor housing.
How could light pass that stage and project an image of the contour of the bellows plate?

Could it be that the masking plates are retracted too much so that light spills through their guides?

The negative carriers for the M601, 605, 670 etc don't allow this light to spill. So the OP needs to be clearer.

Ian

 

[Andre Noble]

I get same ring with Omega enlarger. It is internal reflection not of consequence once one places film in the negative carrier and hence light path. Don't worry. Be happy.

 

[teekoh]

Hi Ian, Thanks for your replies. What other info should I provide?

 

[Ian Grant]

Hi Ian, Thanks for your replies. What other info should I provide?

I think we've now ascertained that there isn't a problem, the light spill wouldn't be there with a negative carrier in place provided you are using the Durst carrier supplied with the enlarger.

Ian

 

[AgX]

I'm totally confused now: without carrier there should be an image of a disk with four recesses not just that rectangle and that contour.

EDIT: At least I assume so. Got no Durst at hand.

 

[Ian Grant]

I'll check my enlargers later (I have 3 or 4 Dursts)

Ian

 

[Ian Grant]

If that's the underside of the casting that the negative carrier sits on then all you're seeing in the other photo is a slight reflection of light from the edges of the metal piece that holds the bellows in place, it's different shapes on myM601 and M670. The paint is black satin finish which will reflect light. It's not a light leak though and will have no effect at all.

Ian