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brighamr
31-Aug-2008, 11:50
Hi

Just started 4x5 and there seems to be a lot of dust on my negs
I have used hp5 and txp 320 which were pretty clean but then I got a new Fuji quickload holder and some arcos but this seems to be worse
Obviously not all the negs have the same amount of dust but on the whole the quickloads seem a lot worse
I have had all my negs done at the same b/w pro lab in London and don't want to start blaming anybody
I just would like to know
"What is normal"
I have read about dust in film holders and I don't have a dust free room to load in
just a light tight bathroom but I did think that the quickloads were supposed to deal with dust

I also do not have a scanner so I can't really post any negs to look over

Thanks for any advice

robin

London

Bruce Watson
31-Aug-2008, 12:15
These are B&W negatives, yes? Are you talking about clear spots on the negatives? If so, these are caused by dust blocking the light at the time of exposure. This kind of dust should be nearly completely eliminated by the quickloads. About the only way that would not be true is if the inside of your camera is dirty, particularly the inside of the bellows. If this is a problem, use a damp cloth to wipe the inside of the camera paying close attention to the bellows -- get every fold in all four directions. If the camera is really dirty you may have to repeat this several times.

The above kind of dust will show as black spots on the print (because of the reversal from negative to positive). If you are seeing white spots on the print it can come from many sources. The primary source is from dust on the negative itself blocking light transmission through the enlarger to the paper. Secondary sources are dust in various parts of the enlarger but mostly the negative stage (if the dust is in focus, it just about has to be there). One of the surprise sources of dust (for me anyway) was the ceiling and walls of my darkroom.

If the negative surface is clean, and the enlarger is clean, and the problem persists, it can well be grunge (dirt, improperly filtered water/chemicals, poor film drying, all sorts of reasons) embedded in the emulsion. This is a processing error and you'll have to take it up with your lab.

The take away message here is that quickloads start out cleaner than any film you would load into a film holder in a home darkroom. They should practically eliminate dust at exposure time, if (a big if I grant) the inside of the camera and the quickload holder is clean.

Nathan Potter
1-Sep-2008, 07:52
Of all the quickloads I've used, Fuji Velvia, and Readyloads, Kodak TMax, I've never found a dust spot imaged during exposure - at least that I've recognized as such. Occasionally I'll get an image of a Maine black fly that rested on the film plane during exposure. I'd troubleshoot as Bruce suggested above.

Nate Potter, Austin TX.

hmf
1-Sep-2008, 17:53
The greatest advice I've ever gotten to help eliminate dust spots came from Carl Weese: use an antistatic brush to clean your holder/darkslide immediately before inserting it in the camera, and to pull the darkslide slowly. He claimed that static elctricity sucked the dust off the slide and onto the film when the darkslide was pulled.

I still clean my holders carefully and store them in a plastic bag, but his technique seems to have made more difference than all other precautions combined.

Fred Braakman
1-Sep-2008, 21:51
HI,

I recently loaded some film into my Fidelity holders, after having used Readuloads for some time. There was an etreme amount of dust on the film. My Readyloads were always very clean.
Does the dust enter the holder when loading the film, or when the slide is pulled just prior to exposing the film?

If the dust enteres the holder when loading the film, is there a way to eliminate static at that point?

fred

Philippe Debeerst
2-Sep-2008, 04:34
I think that dust IN the CAMARA/BELLOWS is at least as problematic as dust in the holders. It is my experience that wide angle bellows are more prone to hold dust than the normal bellows. The one I have for my Linhof at least, but this is one made in a velvet like textile. So, I clean the bellows time by time with the vacuum cleaner, just to be sure.
Just my € 0,02...

Philippe

Alan Rabe
2-Sep-2008, 12:24
First dust spots on your film can also be because you have dust on your lens. Make sure it is clean. It is easily forgotten.

I used to get a bit of dust loading film into the holders. Then one day I tried something new. As dust does not fall up I turned the holder and the film over and loaded upside down. I have had very little dust since changing to this method. I also found that the angles involved actually made loading the film easier, everything just lined up perfectly.
However you do have to watch static. There are ways to control it. I use one of the anti static brushes to clean my holders. And keep your lens clean.

ic-racer
2-Sep-2008, 19:40
Question for those using zip-lock bags. Do you re-use them? Or how long do you use them? One holder per bag?

anchored
3-Sep-2008, 08:56
On the zip-locks bags... I use them and also re-use them unless they get tears.

But... more of a question than an answer: I've been told the standard ziplocks can also be a bad thing, as they are prone to holding static charges. I haven't personally noticed any problem and have continued to use them.

ic-racer
3-Sep-2008, 12:03
On the zip-locks bags... I use them and also re-use them unless they get tears.

But... more of a question than an answer: I've been told the standard ziplocks can also be a bad thing, as they are prone to holding static charges. I haven't personally noticed any problem and have continued to use them.

Good point, and another reason for asking. Plastics and rubbers don't allow electrons to move around on their surface and thus will hold a static charge. Those fancy 'anti-static' bags are treated to behave like a metal where the electrons can move around and easily discharge the whole bag with contact to a ground. Seems good in theory.

My last negatives I processed had the dust only on the top and bottom of the image area, just near the edge. After seeing that I checked a holder just sitting in my camera bag and sure enough, there was a lot of dust around the opening for the dark slide. I can easily see how that dust 'jumped' right on the film when I removed the dark slide. Thus showing me I really need to keep the outer part of the film holder as clean as the innards.