Beseler Enlarger focusing Issues

Discussion in 'Black and White' started by RyanDunn, Feb 3, 2018.

  1. AJG

    AJG

    +1 for Paul Hoyt's advice. Both Aristo and Zone VI cold lights usually drop into the condenser housing with the condensers removed. Your color head will give you diffusion equivalent to the cold light heads, and you can use the magenta and yellow filters to vary contrast with VC B&W papers also. As for the temperature/buckling issues, I haven't used a Beseler color head so I don't know how that will effect your results. If you do get a cold light head, be aware that light output varies with how long the light has been on and that you generally want to turn it on to warm it up a bit before printing. If you can get the later Zone VI version with either the Zone VI stabilizer or the last version with the Zone VI compensating timer then the occasional frustrations of printing with a cold light (varying exposure from test to print or print to print if you're making multiples) just go away. These devices rely on a photo cell built into the head and vary voltage (stabilizer) or time (compensating timer) to keep exposure variation within 1% or so. I routinely made multiple prints with both set ups that matched perfectly in exposure with a wide variety of printing papers.
     
  2. Probably a PITA, but apparently people have built DIY LED heads for enlargers with some success.
     
    RyanDunn likes this.
  3. That's not a bad idea. I already have the diffusion chamber insert, Building the fixture to fit around it & mount seems to be worth a shot, maybe? o_O Although I bet it would be cumbersome to switch back to the condenser head. With the older Aristo heads I'll have to look around to see if the lamp(s) they take are readily available when they burn out. That's probably not an issue for the later Zone VI model heads, especially if they use LED lighting.
     
  4. 'Cold cathode' heads are basically a fluorescent tube, and even when new have warm-up time issues.

    Most cold light diffusion heads will be quite a few years old now, and the tubes may have gone soft and have low output. Replacement tubes will be expensive, if obtainable at all.

    The tubes are also driven at a high voltage, and so the wiring needs to be in good condition to avoid a nasty shock.

    For those reasons I would also recommend building an LED head. White and RGB LEDs are cheap and easily found these days. They don't need any warm up time and have an indefinite life.
     
    RyanDunn likes this.
  5. AJG

    AJG

    Zone VI never used LEDs that I'm aware of, but I would point out that my first cold light lasted for 18 years and thousands of prints without needing replacement when I sold it and bought my current Zone VI enlarger with VC head that still works 17 years after I bought it. Zone VI products were generally well designed and well made, if somewhat expensive when new.
     
    RyanDunn likes this.
  6. As to enlarger focus: Most enlarger lenses fail to project a uniformly tack sharp image, corner to corner as most suffer from coverture of field. The counter measure is to compose and then focus on a selected spot about 1/3 of the way between center and corner. This methodology helps achieve a uniform focus. Now every lens has a sweet spot, likely this will be about 2 f-stops down from wide-open. With that in mind, compose wide-open, focus using your grain focuser, stop-down, now re-focus. The re-focus is important because most enlarger lenses will suffer a slight shift in focal length as you stop down. The countermeasure is to touch-up the focus with the lens set to the actual working aperture you will be using.


    As to type of lamphouse: The condenser enlarger uses two plano-convex lenses that cause the light to hit the negative with parallel rays thus they transverse the negative taking the shortest possible path. Since all negatives have turbidity, the shortest path will deliver higher contrast. A condenser enlarger realizes about 1 to 1 ½ paper grade more contrast as compared to a diffuser enlarger. This extra contrast adds to the apparent sharpness of the image. When it comes to sharpness and pizazz, the condenser enlarger wins every time.


    The condenser enlarger falls out of favor mainly because the resulting prints generally are plagued with dust spots. Dust fluff always sits on the top of the negative. The parallel light of the condenser casts harsh shadows thus the need to spot the prints is increased greatly. A diffuser enlarger is favored mainly because the light is totally diffused so dust fluff cast indistinct shadows thus the need to spot is greatly reduced. The downside is, lower contrast and lower apparent contrast.


    Portrait photographers favor the diffusor enlarger because the resulting prints are more “buttery”. Color negative printers most always choose a diffusor enlarger because of the they mitigate the task of spotting. The “cold light” was introduced when the circulene florescent lamp became available and incorporated into the enlarger lamphouse. They offered a simple way to get a highly diffused light and they run cooler than their tungsten counterparts. Today, the diffusion color printing lamphouse uses an integration chamber. This is a cube or sphere, flat white with lamps that play on the chambers interior walls. The idea is to force the light to reverberate all over the place so that it arrives at the negative plane without direction i.e. totally diffused.


    Also, a flat field enlarger lens is costly but they do the best job. The focal length must be equal to of greater than the corner to corner measure of the negative format, otherwise a vignette is likely.
     
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  7. paul ron

    paul ron NYC

    +1 with Alan.

    When I overhauled my Bessler 45MCRX a couple months ago I was determined to go back to condensers. I always had heat problems with the conventional 212 bulb despite the heat glass. Thats what convinced me to get the Arista (then later a ZoneVI) cold light back in the early 80s. My Arista had the W45 bulb and the Zone had the newer V54. Either did a good job with and without the 40Y filter I see so many using plus the difference between condenser and cold light was so minimal... just compensate in paper grades to make up the difference. Without filters my cold lights gave me a grade 3 using Illford MGIV FB. Do some negative tayloring, you can get that contrast back easy enough.

    Since im upgrading everything, I did some experimenting with ordinary house LED bulbs, 60W equivalent- 4000K seemed best for multi grade use. They give off an even light and they are absolutely much cooler, no after glow and instant on, thus eliminating the heat neg popping syndrom. BTW I also painted my light head interior ultra flat black since it was a semi gloss black from the factory... that eliminated some of the typical halo on the light circle generally responsible for clipping the corners a bit.

    The bulbs worked great but what became a PITA was constantly having to adjust the condenser height to optimize the formats I was working. I switch between 645, 6x6 6x7 9x12 and 4x5 quite often. So tweaking it each n every time just wasn't something I was accustomed to when using the cold light.

    The cold lights I have are for 4x5 enlargers but I did adapt one for my son on a 23C enlarger. I cut off the lamp head leaving the filter drawer in tact. I had to make a box for the head to sit on and a plate for the condenser bellows to fit in jsut above the neg carrier stage. The diffuser was custom cut white plastic to fit exactly inside the cold lights mouth and held in by a couple tabs of silicon on its edges. You can use a diffuser in the filter drawer instead. That enlarger has been working fine for the past 20 years... now in my garage collecting dust.

    As for the bulbs in these cold light heads getting weaker... doesn't seem to be a problem at all here and my lights are pretty old. I bought a spare bulb as a back up and still have it in the box waiting for that day.


    Ill post some pix tomorrow if you are interested?
     
    RyanDunn likes this.
  8. I have had both the Beseler MX series enlarger and the Zone VI Series II enlarger w/variable contrast head. Originally the Beseler had the Aristo cold light retro fitted with the photo cell and the Zone VI stabilizer, and the Series II enlarger had the compensating timer. I often wondered how the compensating timer could compensate for the fluctuations of the 2 grid system. The light output might vary, but the timer would not know which tube (color) was fluctuating. I will admit the Zone VI enlarger was easy to work with, but the light was not as bright as I would have liked. I did speak with a photographer that had acquired one of the few LED Zone VI heads that Calumet sold for the Series II Enlarger. He said the light output was very low and exposures were long for 16X20 prints from his 4X5 negatives.

    I found using the Beseler setup with variable contrast filters and the stabilizer gave me the printing speed and control over the light output that satisfied me. Then one day I saw an ad in my Craigslist for a Ferrante Variable Contrast Lamp for a Beseler MX series enlarger. I bought it and I found that even though it is a cold cathode ray two grid system [actually 3 grids, but that is another story], the light output is very stable. I printed for years with that system and made some of my best prints. It is a diffusion head that uses the Beseler condensers; I suppose that would be the best of both worlds for Alan.

    I have never used a color head for variable contrast printing. I do know they have a mixing chamber and the light exits through a diffusion disk. I believe the lamps are "hot", and the fans are necessary to cool the housing. I would assume there might be an issue with negative buckling, but I am sure there is somebody here who can definitively answer that question.

    Paul
     
    RyanDunn likes this.
  9. Thanks Alan for explaining the image focus drop-off to rest with a condenser system. I did some test prints after my first posting & seeing the edges fairly sharp with my loupe really put me at ease. I will have to do some more testing to hone in on that sweet spot. Coincidentally I was focusing like you suggested. Wide open, than again once I stopped down for printing. I'll have to do some more testing to find the best area to focus on & F/stop.
    I don't do much portraiture, but missing a spec of dust on the negative while printing can be frustrating, not to mention small scratches. Plus it would be nice to have the option of switching between the 2 systems. Heck, I might like the diffusion system for particular images.
    Paul Ron, - yes please. That would be great! I have 2 x 23cii enlargers, one, ironically, the newer model hasn't been kept up nearly as well as the older one - which I primarily print from. It would at least give me some idea's. Whether I can find one or build one from scratch with some LED lights. Either way seeing how you modified it would be very helpful.
     
  10. paul ron

    paul ron NYC

    I hacked sawed the light off the filter drawer and cleaned it up with a file.
    I used epoxy to hold the parts together. I also forgot you will need a small plate under teh filter door.
    For the plates, you can use 1/4" plywood.
    Silicon the condenser head bellows in place.
    I used a neoprene weather tape as a gasket for the 4x5 light to sit on.
    A diffuser can be put in the filter drawer, I cut mine to fit inside the light and siliconed it in place.

    When using this setup, I keep the condenser height adjusted to a point the negative carrier can open without any tension.

    PM me if you have any questions?



    PSIMG_20180208_143934.jpg PSIMG_20180208_144031.jpg PSIMG_20180208_144240.jpg PSIMG_20180208_144518.jpg PSIMG_20180208_144613.jpg
     
    Last edited: Feb 8, 2018
    RyanDunn likes this.
  11. Vincent Peri

    Vincent Peri Metairie, LA

    I heard you can use the Beseler 23C's color head as a cold light head, just dial the filters to zero. Is that true?
     
  12. Hi Vincent,
    A "cold light head" uses a cathode ray tube, or tubes in a variable contrast housings; cathode ray tube, think neon lights, fluorescent lights. I don't believe the Beseler color head uses cathode ray tubes. The color heads have protocols for mixing the intensity of the blue and green filters for B&W variable contrast papers. Graded papers respond to the blue spectrum only. I am not sure what light you would get with both green and blue set to zero. Either the lamp housing is a "cold light source" or it is not, regardless of filter settings. Don't confuse "diffusion" printing with "cold light" printing. An incandescent bulb can be the illumination source of a diffusion printing system.
     
  13. Vincent Peri

    Vincent Peri Metairie, LA

    Thanks, Paul.

    I have a Beseler color head in storage with a Beseler 23CIII and 50mm f/2.8 El Nikkor. I hope to set up my darkroom in the next few or more months.

    We'll see what happens then LOL. I'll only be using Ilfobrom Galerie graded paper.
     
  14. paul ron

    paul ron NYC

    A color head is also very usefull with multi graded papers ya know? If you ever decide to try it... read the specs and lit on Illfod filters... you can get the chart that shows you how to use a color head as VC filters. Again you will still have heat to deal with now exhausting with a fan. Those hallogen bulbs burn so hot. My color head is still sitting in the garage somewhere.

    Graded papers love the cold lights. I used the Arista W45 when I got my first one. Back then, AGFA Record Rapid, Portriga and Brovira and other Bromes were popular and all wonderful papers each with their own charachter. I thought I had it all forever. What I liked about my cold light, my 6x7s and 4x5 werent popping anymore plus I like the even light.
     
  15. That's very helpful Paul, thank you for the pics & notes! One of the things I was grappling with was what would be the best way to mount the head & how to configure the upper bellows. Cutting off the head above the filter drawer solves both those problems. Than it's just a matter of building a couple mounting boards for the cold head & upper bellows for it to all fit together. Living in Arkansas (good god I cringe every time I say that! :D) Craigslist doesn't offer much in the way of used equipment, so Ebay has become my best friend for used photo equipment like a nice cold head. Plus that concept gives me a great starting point if I went the route of building a cold head.
     
  16. paul ron

    paul ron NYC

    Ryan, keep an eye on the classifieds here and Photrio/Apug.... PHOTRIO

    I always see them pop up, especially for 4x5s... they seem more common rather than the smaller C23s size. Used they go for about $100 for the ZoneIV.

    The Arista is just as good... they are both the same bulbs, wiring and blast system.

    PM me if you do get the lamp? I can giive you my adapter. I have 3 more heads for the 23 including a color head.


    .
     
  17. Nice! Thank you - That is very generous of you!!! I've started looking on the various forums & sites .Ebay has an auctioning running right now - Zone VI head with the stabilizer control (w/intensity & dry down function) "new in box with instructions", made for Omega D2,D3,D5, & super C. Looking at it, the "dry down" function probably needs the Zone VI timer? Would that head work as it is w/o the Zone VI timer? It has 11 watchers, so it might go above my budget right now. Probably find someone on the forums at a better price, but we'll see. The seller doesn't have any other information as to the model type listed. I'll msg him/her & try to find out. With your modification technique I don't suppose what model the head was designed to fit really matters does it?
     
  18. paul ron

    paul ron NYC

    I'll measure the hole. I don't think it matters since the light just sits up top.

    as for stabilizers n dry down, never used any of it. dry down? hahaha close is close.... I'm not making posters, I'm making photographs.
     
  19. I never saw the need for a dry down feature either. Observations in different papers & the test printing sessions work just fine for me. :D After looking at one for sale on APUG (not sure if it's sold yet), They look like the same model - even though Apug one states its for the 45MX enlargerl. The pictures on Ebay doesn't show the front of the regulator, where the stabilizer line connects to the lamp & monitors the light output I believe. The one on APUG says it's for graded paper, which I'm waiting to hear back from the ebay seller for more details. I looked for an explanation in the difference between the graded vs VC head in regards to printing, but does it really matter if one uses a graded head with VC paper & use the contrast filters when called for, or VC head on graded paper? Is it the color temp of the light?
     
  20. Contrary to popular belief, diffuser heads do not give a less-sharp image than condenser heads. Not when an opal lamp is used with condensers anyway.

    Film grain is equally well defined in the print when using a diffuser head as with a condenser. The main difference between the two is a slight drop in contrast with the condenser head when printing silver-image negatives. (This is due to light scattering taking place proportional to density with a condenser/point source system, which artificially increases contrast.) The effect can easily be counteracted by a slight change in paper grade.

    There is no 'buttery' effect - whatever that means, and very little masking of dust, unless it's a good distance away from the emulsion surface. As on the surfaces of the condensers or top surface of a glass carrier.

    I think people see the word 'diffuser' and immediately associate it with a softening filter over the lens. This is not the same thing at all as diffusing light prior to focussing. The image plane remains just as sharp, and any softening is mainly in the imagination of people that have never used a diffuser head.
     
    Last edited: Feb 10, 2018

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