Support our Sponsors, they keep FADU free:   AG Photographic   Keyphoto   The Imaging Warehouse   Process Supplies   RH Designs   RK Photo   Second-hand Darkroom Supplies   Silverprint Ltd

Notices

Go Back   Film and Darkroom User > Equipment > Darkroom

  ***   Click here for the FADU 2015/2014 Yearbooks   ***

Reply
 
Thread Tools Search this Thread Display Modes
  #21  
Old 2nd August 2017, 12:11 PM
EdmundH EdmundH is offline
Friend
 
Join Date: Jan 2016
Location: North Norfolk
Posts: 348
Default

Quote:
Originally Posted by CambsIan View Post
Hi Mike,

I use a lamp like that, so your post made me wonder as well.

Had a very quick google, and came up with this.

https://www.amazon.co.uk/THINKMORE-B...ce+halogen+75w

Have no idea if it's any good, may be the wrong colour temp for colour though

This one is similar but cool white, only 4000k so not daylight though

https://www.amazon.co.uk/Aurora-Prem...A34AMN3SJ235OF

Ian

What does anyone think
These bulbs may be usable for black & white, but I am fairly certain that they would cause problems for colour printing due to their uneven spectrum. The attached chart shows how the various light sources differ.

I also notice that the base for the bulbs you've shown is given as GU5.3 whereas the original halogen projector bulbs are GU5.36 - I tried a 2 pin halogen bulb from a domestic fitting in my enlarger a while ago, and although it looked similar, the pin spacing was different.
Attached Thumbnails
Click image for larger version

Name:	led-lighting-2.jpg
Views:	31
Size:	37.0 KB
ID:	2784  
Reply With Quote
  #22  
Old 2nd August 2017, 05:54 PM
CambsIan's Avatar
CambsIan CambsIan is offline
Friend
 
Join Date: Jun 2011
Location: Cambridgeshire
Posts: 1,226
Default

Hi Edmund,

Thanks for the info, food for thought.

Ian
__________________
Learn to live, live to learn
Reply With Quote
  #23  
Old 2nd August 2017, 08:51 PM
alexmuir alexmuir is offline
Friend
 
Join Date: Jan 2010
Location: Glasgow, Scotland.
Posts: 2,251
Default

I've just tried an LED GU-5.3 in my Durst enlarger and can confirm that it doesn't fit the holder. The prongs are too close together compared to the correct bulb. The difference in designation pointed out by Edmund is clearly significant.
The other point I've noted relates to the Diall LED bulbs from B&Q. I picked one up today to use in my Durst M601. Having looked closely at it, however, I don't think it will work in this type of condenser enlarger. The bulb in the M601, and similar models, is aimed at a 45 deg mirror which reflects the light down onto the condensers. The LED bulb has an opaque section which comes up to around half the height of the globe. I haven't tried it yet, as the enlarger has the colour head fitted at the moment, but I suspect it won't send enough light in the right direction for even illumination. I can see it working perfectly in the more conventional arrangement where it shines straight down onto the condensers. I assume that's how the Meopta system works, but please correct me if I'm wrong as I would be delighted if the bulb will work in the Durst. I will try it out tomorrow if I have time and report back.
Alex


Sent from my iPhone using Tapatalk Pro
Reply With Quote
  #24  
Old 3rd August 2017, 07:42 AM
Richard Gould Richard Gould is offline
Friend
 
Join Date: Dec 2008
Location: Jersey Channel Islands
Posts: 5,070
Default

Meopta's are straight down, I have read that some of the reflecting type enlargers have adjustments to the bulb so that with adjustments the LED bulb can work, I don't know if it applys to Durst's as I have not used one,but it could be worth having a look,
Richard
Reply With Quote
  #25  
Old 3rd August 2017, 08:57 AM
alexmuir alexmuir is offline
Friend
 
Join Date: Jan 2010
Location: Glasgow, Scotland.
Posts: 2,251
Default

Thanks Richard. The bulb holder is movable to adjust for even illumination. I will try that and measure falloff at the corners.
Alex


Sent from my iPhone using Tapatalk Pro
Reply With Quote
  #26  
Old 3rd August 2017, 10:29 AM
Richard Gould Richard Gould is offline
Friend
 
Join Date: Dec 2008
Location: Jersey Channel Islands
Posts: 5,070
Default

I can't aee why with a bit of adjustment it shouldn't work, when researching LED bulbs before I decided to give it a try I have read several posts on other forums about adjusting the bulb holder so that the heat sink is out of the way and illumination is even across the hole area, worth trying it, if you can get it working you can save on both bulbs(if you can find 150 bulbs they are around 10 each) and use a llot less electricity, plus no more negative popping due to heat, in fact I have taken out the glass shield in my Meopta, bit less to keep clean, and I find they are brighter
Richard
Reply With Quote
  #27  
Old 3rd August 2017, 02:50 PM
Mike O'Pray Mike O'Pray is offline
Friend
 
Join Date: Oct 2008
Location: Daventry, Northants
Posts: 7,721
Default

Thanks Edmund and Alex. It looks as if there may be no equivalent for the two pronged Tungsten Halogen for a Durst colour-head 605 as things stand.

Pity. Mind you when you think of it, the LED bulb manufacturers are aiming at a quite different domestic bulb market. Maybe they will never make a two pronged bulb for the enlarger market as it will never repay their investment.

Mike
Reply With Quote
  #28  
Old 3rd August 2017, 04:01 PM
EdmundH EdmundH is offline
Friend
 
Join Date: Jan 2016
Location: North Norfolk
Posts: 348
Default Error

I'm sorry, I misquoted the base type for the two pin 12v/100w bulbs - it should have read GZ6.35. In fact these halogen bulbs are widely used for stage and disco lighting, and can be bought very cheaply from non photographic sources.
Reply With Quote
  #29  
Old 10th August 2017, 09:01 PM
M Stewart M Stewart is offline
Friend
 
Join Date: Nov 2016
Location: Milton Keynes, UK
Posts: 72
Default

Quote:
Originally Posted by EdmundH View Post
These bulbs may be usable for black & white, but I am fairly certain that they would cause problems for colour printing due to their uneven spectrum. The attached chart shows how the various light sources differ. ...
Hi Edmund,
Many thanks for posting the spectra of different light sources. Very useful, not only for enlarger usage, but also for choosing an LED for microscopy under-stage lighting. I made the mistake recently of buying a 6,000K or 7,000K wire ended LED, hoping to get something more blueish than a "warm white" but when I tried it, the light was a good blue, and very little use to me. I'd hoped for something a little "colder" than a Warm White LED. What I bought was a Maplin N83KG and very blue, despite being described as "white".
I've got a lot to learn... I'm pleased that they're now so cheap, and easily experimented with.
__________________
Malcolm Stewart
Milton Keynes
Reply With Quote
  #30  
Old 10th August 2017, 09:34 PM
alexmuir alexmuir is offline
Friend
 
Join Date: Jan 2010
Location: Glasgow, Scotland.
Posts: 2,251
Default

I have been thinking further about the idea of using the 12V LED lamps to replace the halogen types in Durst and other colour heads. Is the answer simply to replace the lamp holder with a G5.3 type? These are cheap and readily available, and come with two leads attached which could be swapped for the originals. Has anyone tried this? I anticipate the advantages would be cooler running, long life and perhaps resistance to the colour change that affects halogen lamps as they age.
Alex.


Sent from my iPhone using Tapatalk Pro
Reply With Quote
Reply

Tags
bulb, darkroom, enlarger
Support our Sponsors, they keep FADU free:   AG Photographic   Keyphoto   The Imaging Warehouse   Process Supplies   RH Designs   RK Photo   Second-hand Darkroom Supplies   Silverprint Ltd

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Durst M800 Bulb RobertP Darkroom 2 16th January 2017 06:55 PM
Which enlarger bulb??? Brock Darkroom 9 11th September 2012 09:01 PM
Safelight bulb HopALong Darkroom 3 6th March 2012 08:12 PM
Multigrade with tungsten bulb? JamesK Darkroom 14 16th October 2011 09:12 AM
Enlarger bulb Domingo Darkroom 10 3rd August 2011 03:56 PM


All times are GMT. The time now is 04:59 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.