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Author Topic: Any good CFL bulbs?  (Read 14637 times)
mcmorrison
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« Reply #20 on: November 28, 2007, 09:26:29 AM »
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Hello Andrew,

Many brands now offer a range of temperatures. I can see wanting warmer and cooler CFLs in different circumstances, so I wonder which brand, or manufacturer, has bulbs with the best light quality?

Thanks!

Michael Morrison
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Sven W
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« Reply #21 on: November 28, 2007, 04:47:00 PM »
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Measurements from my two viewinglights.
Left, from a very expensive viewingboooth,
and on the right, the cheap, but very correct Solux.
What do you choose?

/Sven
[attachment=4068:attachment]
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AndyF2
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« Reply #22 on: November 28, 2007, 11:48:19 PM »
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Hi everyone,

Do you know of any good compact fluorescent bulbs? By "good", I mean that the CFL bulb doesn't make colors look all weird, especially prints!

[{POST_SNAPBACK}][/a]
I posted a comparison of the X-Rite Color Checker under different lights recently; the composite image is at [a href=\"http://www.pbase.com/andy_fraser/lighting_comparisons]http://www.pbase.com/andy_fraser/lighting_comparisons[/url]  The objective of the test was to see if the spectrum spikes of various CFLs would be visible on the colour patches, and to compare their overall colour rendition to the reputedly good Solux lamps.

The image is a collection of exposures of the chart under the specified lights (flash, household CFL, photographic CFL, daylight CFL, household halogen, Solux 4100, Solux 4700).  Once the total image was put together it was white balanced using the white square with flash exposure.  

The colour temperature differences can be compared by examining the first few "gray" columns, and between any two lamps, compare for abnormal colour shifts in the colour patches along their rows.  The colour balance between rows is certainly apparent.  The colour errors on patches are sometimes subtle.

The 60W daylight halogen manufactured by Globe (6th row) is the most obvious weird lighting to start with, especially it's effect on the purple patch.

Some notes on how this total image was generated:
- The photos were taken autoexposed with a Canon XTi
- Each raw file was converted to a tiff in LR without any change in whitebalance
- The rows of all the tiffs were cut&pasted into one total chart in CS3
- The first white square of each row was replicated and placed at the left end, and that square was blurred with the Average tool (I really only needed this for the flash, but did it for every row anyway)
- The image was flattened, saved as tiff, and brought back into LR
- The white balance was set using the averaged white square under flash lighting
- The resulting file was saved as a jpeg
- The lamp was mounted on the ceiling, 30" back from the wall, and the top of the chart was 28" down from the ceiling.


Some remarks:
- An averaged white square had to be used to set the WB, since the R,G,B values are not exactly the same at every point across the original square.
- There is a small exposure variation between any two particular rows that has not been adjusted.  This is at most 5%.  Since the R,G,B of each light are not in the same proportion, I hadn't decided how to correctly calculate what exposure compensation to apply.  However, the rows can still be compared since what we're looking for are any individual patches that deviate more than the rest of the row.
- A test image containing a larger number of more specific colours patches than the X-Rite chart, possibly using paints or pigments would be good for a second version of this test since I expect the difference between a flourescent and a good halogen or flash should be apparent.
- The $5 Globe CFL compares reasonably well with the $15 Cameron "Digital Imaging" CFL.  It's distributed by Cameron, sold at Henry's and Vistek in Canada.  It's package is marked 5000K, true daylight, 26W, 1600 lumen, type 5071015.
- The Canon flash is of course neutral since that's how I set it in Lightroom.

Some personal opinions and conclusions:
- MR16 halogens provide a better light due to more intensity in beam than CFLs which spill light everywhere
- The solux have a more even intensity across the width of the beam than the generic MR16 (not on the chart) I bought from a hardware store.
- The 4700K Solux is too bluish for residential use, it's too cold or "technical" a light.  I like the 4100 better.  There is a 3500, I have not tested it.
- The overall effect of light from multiple MR16 beams on the wall is more pleasant than the CFL lamps used previously.
- A minor requirement of artwork lighting in the home is that the wall itself is evenly illuminated, and the 24 degree beam (shown in the setup photo on pbase) is too narrow for that.
- I've ordered eight of the Solux 4100K, 35W, wide (36 degree) floods.
- Until the Soluxs arrive, I have $2 Ikea MR16s installed.  They're not really "warm white", they're more like "beige" compared to the 4100.
- It would be interesting to redo this test, but with a test chart providing a larger number of very specific colour patches that is still a valid representation of the colours encountered in nature, but would also be capable of showing any real effect of flourescent spectrum spikes.

(The pbase site allows comments to be left; probably not useful since I don't want to admin that ro maintain a discussion over there)
Andy
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Ernst Dinkla
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« Reply #23 on: November 29, 2007, 02:56:41 AM »
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I posted a comparison of the X-Rite Color Checker under different lights recently; the composite image is at http://www.pbase.com/andy_fraser/lighting_comparisons 

(snip)

- The 4700K Solux is too bluish for residential use, it's too cold or "technical" a light.  I like the 4100 better.  There is a 3500, I have not tested it.
-
Andy
[{POST_SNAPBACK}][/a]

Andy,

Are the two bottom rows of the test results not reversed ?
Sorry, I think I get it, the white balance pulls them to the opposite side of the color shift.

It's a nice summary.

I have attached 6 Ikea 12 volt, adjustable, spot armatures straight at the aluminium profiles in the ceiling with the Ikea halogens and will put another 4 there too. They are not heavy and by exchanging different spot angle halogens I can adjust for the size of the prints. The light was not even enough and is too warm. Have to exchange the lamps for Philips Diamond line 4100K (Solux license).  But there is a bottle of fluoric acid here so for the time being I matted the front of the Ikea bulbs slightly and the light is much smoother now but of course still too warm. With a mix of the 10, 24, 36 degree Diamondline spots it should work. It would have been nice to have rectangle masks on the lamps but it's good enough.

Ernst Dinkla

try: [a href=\"http://groups.yahoo.com/group/Wide_Inkjet_Printers/]http://groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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Ken Alexander
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« Reply #24 on: November 29, 2007, 06:06:58 AM »
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Hi everyone,

Do you know of any good compact fluorescent bulbs? By "good", I mean that the CFL bulb doesn't make colors look all weird, especially prints!

Normally I use a 35-watt SoLux 4700 K bulb or diffused daylight to evaluate prints, but for the rest of the house I would much rather use CFLs to save energy. But the CFLs I've tried all have funky spiky spectrums (nature of the beast?) and my prints all look quite bad in them.

Suggestions?

Thanks,
Eric
[a href=\"index.php?act=findpost&pid=135530\"][{POST_SNAPBACK}][/a]


Hi Eric,

I asked a similar question a few months back and received almost the same replies.  I wanted to be evaluate my prints in a room painted orange-brown and lit with incandescent floods (very warm!).  I ended up going cheap and went to Home Depot and bought some CFLs that operate at 6500K, which is the same as my iMac's monitor.  I installed the bulb in my desk lamp and have been very pleased with the results.

However, the light from a 6500K CFL is relatively cold and harsh looking.  If you wanted to use CFLs as general lighting in other areas of your home I'd go with something warmer (unless you want to turn your home into a print evaluation lightbox!).  It'll require some experimentation, but as a starting point I wouldn't go as cool as 6500K.

Ken
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Slaughter
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« Reply #25 on: January 14, 2008, 06:18:02 AM »
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Do you know of any good compact fluorescent bulbs? By "good", I mean that the CFL bulb doesn't make colors look all weird, especially prints!

I don't think that there are "good compact fluorescent bulbs". On the other hands, there are good "classical" fluo tubes. Not to mention Osram "Color Proof" tubes with color rendering index between 97-98%. These tubes are dedicated to color proofing. They are balanced to 5400K if I am right. I have 2 of these in my digital darkroom with one of them hanging 1.5 meters above my printers. Perfect for color proofing!

I have read that some people want to use "Biolux" tubes from Osram as light source for color proofing. These tubes are not really intended for color proofing although they are referenced with an Ra above 90%. Side by side with the "Color Proof" tubes they show a kind of "magenta" or "rose" cast (IMHO). I also use "Biolux" tubes but not for photography purposes but for myself when I lack sun light (e.g. in winter time).

I have never heard of compact fluorescent bulbs with a color index better than Ra 80. That is far too low for being used as color proofing light source. Even when I visually directly compare tubes with Ra around 93% and the aforementioned "Color Proof" tubes (with Ra around 97-98%), I DO see a difference.

_michel
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digitaldog
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« Reply #26 on: January 14, 2008, 08:18:23 AM »
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CRI is a pretty useless spec to go by and a bit of a kludge to make a light source appear to be closer to daylight for marketing and light manufacturers. CRI was developed in large part to aid in the sales of Fluorescent tubes. There are tiles used to compare under a reference light source but only eight. That's too small a set of tiles. The manufacturers pick the tiles. That make it easy to create a spectrum that will render the 8 tiles and doesn't tell us that the light source is full spectrum. It doesn't tell us how the other colors will render. My understanding is there are two reference sources; Tungsten for warm bulbs and D50 for cool ones. That means that a normal tungsten bulb and perfect daylight both have a CRI of 100! As such, a high CRI is a decent gauge of how well a light will preform in your home but not such a great indicator of how well it will work for photography and proofing. Both a Solux 48 and a "full spectrum" tube from home depot may have a CRI of 97. I can assure you the Home Depot bulb has a giant mercury spike and some spectral dead spots.
« Last Edit: January 14, 2008, 08:18:48 AM by digitaldog » Logged

Andrew Rodney
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« Reply #27 on: January 17, 2008, 08:31:06 PM »
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Here are some that I'm about to try:

"These special Photo CFL (Compact Fluorescent Light) bulbs have a natural "daylight" balanced color temperature of 5500K. These special energy saving bulbs are "flicker free" and specifically designed for digital photo imaging. They produce a soft diffuse light with CRI of 91 and bulb life is exceptional at about 10,000 hours."

http://alzodigital.com/online_store/replac...tm#alzo_1512_55

Robert Liles
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sojournerphoto
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« Reply #28 on: January 18, 2008, 06:30:28 AM »
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Here are some that I'm about to try:

"These special Photo CFL (Compact Fluorescent Light) bulbs have a natural "daylight" balanced color temperature of 5500K. These special energy saving bulbs are "flicker free" and specifically designed for digital photo imaging. They produce a soft diffuse light with CRI of 91 and bulb life is exceptional at about 10,000 hours."

http://alzodigital.com/online_store/replac...tm#alzo_1512_55

Robert Liles
Pushdot Studio
[a href=\"index.php?act=findpost&pid=167894\"][{POST_SNAPBACK}][/a]


TBH I've yet to see a fluorescent that I like. We've a few around the house and I always want to turn them off - saves energy I suppose.

In the UK the government inteneds to phase out incandescent bulbs by 2009 or 2010 I think. I'm more than a little concerned as to date there's no suitable low energy replacement that offers a good quality of light. In the meantime, I might stockpile some MR16 halogens.  

Finally, in the UK solux is hard to find and quite expensive, so I'm going to try out the osram decostar 51 cool blue, which has a colour temp of 4500K for print assessment. Much of the rest of the house is lit with Decostar 51 standard bulbs, colour temp is 3000K and much much nicer than the GU10 mains halogens that seem to be about 2750K - that 250K makes a very noticeable difference.

Mike
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digitaldog
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« Reply #29 on: January 18, 2008, 08:17:13 AM »
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All Fluorescent bulbs have nasty Mercury in them which cause a spectral spike (and when improperly disposed of, which I suspect the vast majority are, produce something worse than greenhouse gasses!).
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Andrew Rodney
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« Reply #30 on: January 18, 2008, 10:19:54 AM »
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I hate the cool white look of the CFLs you find in Home Despot and Wally world so I Googled for warm white CFLs. Found them. They are 2700K. The 100w eq bulb is 27w usage. They're all I use in my house as they are the closest to an incandescent bulb look for warmth of light.
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« Reply #31 on: January 18, 2008, 02:56:24 PM »
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I note that Ikea has been mentioned a few times. I wandered through the lighting section of an Ikea  here in Australia yesterday. Most of the fittings for 12 V halogen were a bit plasticy, but certainly cheap. What concerned me was the rating of 20W for most , 30 W for a few. Solux lamps are available in 35W and 50W. Can anyone offer suggestions re fittings so fires etc are avoided?
Also assuming LCD monitors adjusted in the range 100-140 cd/sq m (depending on ambient lighting) how are people arranging Solux arrays to match, ie how any , what wattage, how far away from prints. Obviously there will be variations with fittings, viewing booths etc, but sharing of this information could be valuable to many readers.
Cheers,
Brian
www.pharoseditions.com.au
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Ernst Dinkla
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« Reply #32 on: January 19, 2008, 04:28:58 AM »
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I note that Ikea has been mentioned a few times. I wandered through the lighting section of an Ikea  here in Australia yesterday. Most of the fittings for 12 V halogen were a bit plasticy, but certainly cheap. What concerned me was the rating of 20W for most , 30 W for a few. Solux lamps are available in 35W and 50W. Can anyone offer suggestions re fittings so fires etc are avoided?
Also assuming LCD monitors adjusted in the range 100-140 cd/sq m (depending on ambient lighting) how are people arranging Solux arrays to match, ie how any , what wattage, how far away from prints. Obviously there will be variations with fittings, viewing booths etc, but sharing of this information could be valuable to many readers.
Cheers,
Brian
www.pharoseditions.com.au
[{POST_SNAPBACK}][/a]

Brian,

You are correct about the 20 W limitation on most Ikea fittings. There are however halogens in 20W available that give 4000 K according to the specs. I have to test whether the fittings can hold 35 W lamps but the way I placed the (frosted) 20 W lamps (+ the frame sizes I can show here) there's about 350 Lux on the picture at night and about 700 Lux with the windows uncovered on an overcast day. I find that enough. For display I will try to get an MR16 solution that will use 20 W 4000K 10 - 38 degrees. For proofing I'm thinking about a DIY Solux like solution with more lamps.

The fittings I used on the ceiling are the Ikea Beryll model that should be used on the wall with a transformer per lamp. However I connected them per 3 or 4 to bigger transformers that get their mains through the ceiling light switches. All nicely covered by the aluminium profiles of the ceiling. There's a small switch on each lamp which makes it easier to point them separately or switch them off for a blank wall. Hope they keep them in the catalog forever.

I expect that there will be MR16 LED lamps with an acceptable color available within a decade if the energy prices go up even more. The ones I tried were bad though.

Have 10 transformers 20 W 12V for sale :-)


Ernst Dinkla

try: [a href=\"http://groups.yahoo.com/group/Wide_Inkjet_Printers/]http://groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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AndyF2
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« Reply #33 on: January 28, 2008, 09:20:55 PM »
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[attachment=4942:attachment]
Quote
I note that Ikea has been mentioned a few times. I wandered through the lighting section of an Ikea  here in Australia yesterday. Most of the fittings for 12 V halogen were a bit plasticy, but certainly cheap. What concerned me was the rating of 20W for most , 30 W for a few. Solux lamps are available in 35W and 50W. Can anyone offer suggestions re fittings so fires etc are avoided?
Also assuming LCD monitors adjusted in the range 100-140 cd/sq m (depending on ambient lighting) how are people arranging Solux arrays to match, ie how any , what wattage, how far away from prints. Obviously there will be variations with fittings, viewing booths etc, but sharing of this information could be valuable to many readers.
Cheers,
Brian
www.pharoseditions.com.au
[a href=\"index.php?act=findpost&pid=168032\"][{POST_SNAPBACK}][/a]
Hi Brian,
Here's what the illumination pattern looks like, with 36-degree wide 35W 4100K MR16 Solux bulbs.  I have one (120V) track on the ceiling, each lamp fixture has it's own built-in transformer so several lamps can be placed anywhere without overloading one common transformer.
The wall does have a distinctive scalloped illumination pattern.  I'd almost want to have a second lighting system to wash the rest of the wall, using CFL or tubular FLs in a low profile fixture, also for when I just want general and not gallery lighting in the home.
Don't use IKEA halogens.  The light they give, compared to 4100K Solux, is "beige".  See my earlier post in this thread and comparison on pbase.
Andy
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William Morse
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« Reply #34 on: January 29, 2008, 10:11:54 AM »
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Hi Andy-

A typical Halogen MR-16 will be "beige"- ie, warmer, 3k-3.2k, instead of your 4.1k w/ the Solux. Other than possible mis-matches with either sunlight or other lighting, not necessarily a problem, as we see "white" relative to the surroundings. (sorry if I'm repeating what you already know)

I looked at your installation photo, and one thing stood out. Your lights hit your frames at a 45° angle, which is higher than optimum, since it will cause more glare, especially for shorter viewers. Optimum is considered to be 30°. or closer to a 2:1 relationship between vertical to horizontal than your ~1:1. For your installation, you might want the lights to be about a foot closer to the wall, for optimum glare reduction. Of course, this would increase the scalloping, as well as the light intensity on the images, so it's a balancing act.

Hope this is of some interest.

Bill

Quote
[attachment=4942:attachment]
Hi Brian,
Here's what the illumination pattern looks like, with 36-degree wide 35W 4100K MR16 Solux bulbs.  I have one (120V) track on the ceiling, each lamp fixture has it's own built-in transformer so several lamps can be placed anywhere without overloading one common transformer.
The wall does have a distinctive scalloped illumination pattern.  I'd almost want to have a second lighting system to wash the rest of the wall, using CFL or tubular FLs in a low profile fixture, also for when I just want general and not gallery lighting in the home.
Don't use IKEA halogens.  The light they give, compared to 4100K Solux, is "beige".  See my earlier post in this thread and comparison on pbase.
Andy
[a href=\"index.php?act=findpost&pid=170457\"][{POST_SNAPBACK}][/a]
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Ernst Dinkla
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« Reply #35 on: January 29, 2008, 11:01:29 AM »
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[attachment=4942:attachment]
Hi Brian,
Here's what the illumination pattern looks like, with 36-degree wide 35W 4100K MR16 Solux bulbs.  I have one (120V) track on the ceiling, each lamp fixture has it's own built-in transformer so several lamps can be placed anywhere without overloading one common transformer.
The wall does have a distinctive scalloped illumination pattern.  I'd almost want to have a second lighting system to wash the rest of the wall, using CFL or tubular FLs in a low profile fixture, also for when I just want general and not gallery lighting in the home.
Don't use IKEA halogens.  The light they give, compared to 4100K Solux, is "beige".  See my earlier post in this thread and comparison on pbase.
Andy
[{POST_SNAPBACK}][/a]


Andy,

I agree on the beige output of the Ikea halogens that I have and that's why I want to replace them with Sylvania Osram 4000K halogens but the illumination pattern on my walls is a lot nicer than what I see in your image. The Ikea Beryll fittings are smaller, the matted halogens fit the frames better with less of a hotspot and wash the wall as well. If the 4000K's are to harsh I will etch the front glasses again.


Ernst Dinkla

try: [a href=\"http://groups.yahoo.com/group/Wide_Inkjet_Printers/]http://groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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AndyF2
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« Reply #36 on: January 29, 2008, 11:35:27 AM »
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I looked at your installation photo, and one thing stood out. Your lights hit your frames at a 45° angle, which is higher than optimum, since it will cause more glare, especially for shorter viewers. Optimum is considered to be 30°. or closer to a 2:1 relationship between vertical to horizontal than your ~1:1. For your installation, you might want the lights to be about a foot closer to the wall, for optimum glare reduction. Of course, this would increase the scalloping, as well as the light intensity on the images, so it's a balancing act.

[a href=\"index.php?act=findpost&pid=170615\"][{POST_SNAPBACK}][/a]
Hi Bill,
I hadn't thought of that; when I was putting up the track, I was trying to avoid putting more holes in the ceiling!  Fortunately the glare isn't apparent.  Something to keep in mind though when I move and install lighting again.
Andy
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« Reply #37 on: January 29, 2008, 11:40:19 AM »
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Andy,

I agree on the beige output of the Ikea halogens that I have and that's why I want to replace them with Sylvania Osram 4000K halogens but the illumination pattern on my walls is a lot nicer than what I see in your image. The Ikea Beryll fittings are smaller, the matted halogens fit the frames better with less of a hotspot and wash the wall as well. If the 4000K's are to harsh I will etch the front glasses again.
Ernst Dinkla

try: http://groups.yahoo.com/group/Wide_Inkjet_Printers/
[a href=\"index.php?act=findpost&pid=170638\"][{POST_SNAPBACK}][/a]
Hi Ernst,
I looked back at your earlier post; you said the lights are frosted.  That would soften and spread out the light.  Is the bulb itself frosted, or is there a diffuser glass in front of it?
My fixtures came with protective glass and I suppose I could have those (or a replacement set) etched or sandblasted.  Or perhaps there are frosted ones already available.
Andy
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« Reply #38 on: January 29, 2008, 02:08:27 PM »
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Hi Ernst,
I looked back at your earlier post; you said the lights are frosted.  That would soften and spread out the light.  Is the bulb itself frosted, or is there a diffuser glass in front of it?
My fixtures came with protective glass and I suppose I could have those (or a replacement set) etched or sandblasted.  Or perhaps there are frosted ones already available.
Andy
[{POST_SNAPBACK}][/a]


Andy,

I have a glass etch fluid here that I have used in the past for etching white boards before they were printed, all steps with a silkscreen printing process. The matting (frosted wasn't the right term) on the halogen glass is subtle but makes the light more even. Of course it reduces the Lux on the frames but I find it enough already.

Ernst Dinkla

try: [a href=\"http://groups.yahoo.com/group/Wide_Inkjet_Printers/]http://groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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Ernst Dinkla
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« Reply #39 on: January 30, 2008, 02:12:14 AM »
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Andy,

Here are some images of the walls. Different space of course.

http://www.pigment-print.com/tijdelijk/Kantoor3.jpg


Ernst Dinkla

try: http://tech.groups.yahoo.com/group/Wide_Inkjet_Printers/
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