enlarger lens cleaning marks?greenspun.com : LUSENET : Large format photography : One Thread
I've just started enlarging my 4x5 negs up to 16x20. Mostly things look very nice! I've had a few concerns with certain negs though. in some that have fine detail (telephone wires, I'm shooting urban jungle stuff)I can't get them to show in the print. I can clearly see the cables when I put the neg on my light board. but they fade to oblivion when printing.
I have noticed that my enlarging lens seems to look like it has a million little white marks. I can only see this when light is coming THROUGH the lens. when removed and looked through (like glasses), it appears clear and scratch free. I am suspecting that there are faint cleaning marks that are causing this problem.
I currently use the Schneider componon s 135mm on an Omega D2, w/ a glassless carrier.
another thought, I don't yet have a 16x20 easel! I just use the lid for the paper box inverted. I have been concerned that it might not be perfectly flat, but I check it and it looks OK. OR, could my enlarger be slightly out of allignment?...this D2 looks to be solid as a rock. FINALLY: I am purchasing a Vivitar six element 135 VHE lens to replace the schneider. the seller claims the lens is actually made in germany by schneider?... could this be true?
-- paul schuster (firstname.lastname@example.org), September 07, 2000
I don't know about the lens but take your 16x20 and look at it closely to see if you see grain from edge to edge. If you don't it will be obvious on all the edges. Now take a grain focuser and check to see if you see grain when you focus in the center, all the edges should have the same without refocusing. If you need to refocus, your enlarger is out of alignment. It is always better to use an easel but with RC, it lays pretty flat. In a pinch at work, I have used the base board when someone else is using the boarderless easel. We have one 20x24 boarderless Saunders and am told we cannot get any more because they are discontinued... If you find one, buy it! Cheers
-- Scott Walton (email@example.com), September 07, 2000.
The Vivitar is either a Rodenstock or a Schneider (if the salesman says Schneider I would believe him) - it's the same as the Componon S if it's a Schneider. Using a glassless negative carrier without an easel is adding insult to injury to your negs. As bad as you may think that your lens is your money would be better spent addressing those two items first. And a laser alignment tool would be a nice third step.
-- Wayne DeWitt (firstname.lastname@example.org), September 07, 2000.
Paul: I use a D-II and find it easy to align if that is the problem. If you are using the condenser lighting system, you may get negative "popping" from the heat. Turn on the light and let the neg warm up, then refocus. As Scott said, check the image from corner to corner with a grain magnifier with the lens wide open, then stop down a couple of stops and check to see if the corners are sharp. An easy way to check alignment on the D-II is to take a piece of glass big enough to fit in the carrier space and draw lines with a small felt tip pen from corner to corner and make some lines across the glass in all directions. The lines are easy to see and you can tell if everything is sharp. I really don't think the very fine lines are causing your problem. The lines may make a very tiny difference in contrast, but probably not enough difference in focus to eliminate something like a power line.
-- Doug Paramore (email@example.com), September 07, 2000.
As thew others have suggested, do check your enlarger for alignment, but I'd bet that Doug identified your problem - contrast. You said your prints look really nice, so I doubt the lens is at fault that much. However, if the contrast is subtle (density of the power lines too close to the density of their surroundings) you may be loosing it because you're using the wrong contrast paper. Try printing a portion of the negative at 16x20 enlargement, using smaller, more economical paper and vary the contrast. Then see if the power lines don't become visible. This is the easiest and cheapest way to check.
-- Pete Caluori (firstname.lastname@example.org), September 07, 2000.
Perhaps you've got one of the experimental 'power line filter' enlarging lenses that were produced in small quantities a few years back!
The patent rights were bought up by the big utility companies, for fear that people would see how much better the environment would look without power lines. Then they'd be forced to take all their overhead distribution down and bury it, out of sight.
There're people who'd pay a small fortune for one of these rare lenses.
-- Pete Andrews (email@example.com), September 08, 2000.
Pete: Surely you jest, sir! You mean there are actually people who don't like black lines running across the landscape and across the faces of beautiful buildings? Could there be some with such little artistic vision that they cannot see the beauty in a row of dark poles and wires with the trees cut beneath running across the face of a mountain? What would the birds sit on? And what would keep the squirrel, owl, and eagle population under control with no power lines to electrocute them when they got on the poles? As a photographer of many years experience, I have always loved the sight of black lines in my prints, expecially in my landscape and historical building pictures. I especially like the effect in the cities, where there are so many of those beautiful lines running in every direction. To say one does like power lines would be as crass as professing a dislike for acid rain.
-- Doug Paramore (firstname.lastname@example.org), September 08, 2000.
It may be that your "fine lines" are not scratches but fungus. Cleaning the interior air to air surfaces on modern lenses is usually sufficient as the adhesive on newer lenses will not support fungus growth. After cleaning the interior of the lens, set it in the sun for several hours to kill any residual fungus so it won't grow back.
Use great care in cleaning the surfaces and don't use the same stuff as you use to clean your glasses - it may wreck the coating. A damp cue-tip with lens cleaning solution works for me.
-- Pete Kiefer (email@example.com), September 16, 2000.
thanks for all the suggestions. I did replace my lens. I noticed the Schneider is probably the original lens that came w/ my omega (it says Omega on it). I guess that makes it pretty old. I removed it and noticed a bunch of black flecks in there. I removed the rear element and blew in there. THEY ALL FLEW AWAY! the lens looks pretty clear now!
-- paul schuster (firstname.lastname@example.org), September 16, 2000.