What lighting are you reviewing prints with?

[Richard.Wills]

8 switchable banks of Yuji 5' ISO3664:2000 leds.

I really should tidy the print room!

[Kyle Jackson]

8 switchable banks of Yuji 5' ISO3664:2000 leds.

I really should tidy the print room!

"Accurate rendering of real life(tm)." I even see LuLa on the screen lol 

[alain]

Vrgb LED emitters (SunLike Toshiba TRI-R technology) are as good as it gets. The one from link are also cheap, and I couldn't detect any measurable flickering using JETI Specbos and 240Hz camera. Yuji are certainly good too (also Vrgb). GrafiLite are just Bgr LED like most video lamps, so they're noticeably worse than Vrgb - spikes in Bgr spectra makes it visually warmer than CCT indicates, and less neutral for B&W prints (usually greenish)

I think I found a led strip with it.  5 meter, 19W/m, 24V, 4000K (other available) and 229,99 euro's :

led strip

[alain]

Hi

Just found some cheap ligth's on amazon.de  (€19,99 for 6) : DiCUNO E27 LED Lampe 9W, Kaltweiß 5000K, ersetzt 60W Glühbirne, 806lm, CRI 98  ProOE Serie

reviews write that's more CRI 96 but with a good R9 value (R9= deep reds)

[Jonathan Cross]

Hi

Just found some cheap ligth's on amazon.de  (€19,99 for 6) : DiCUNO E27 LED Lampe 9W, Kaltweiß 5000K, ersetzt 60W Glühbirne, 806lm, CRI 98  ProOE Serie

reviews write that's more CRI 96 but with a good R9 value (R9= deep reds)

My local electrical supplier (with branches across southern England) sells low profile strip leds for surface mounting. The range from 1ft to 5ft and all are 10W/ft and 120 lumens per Watt, so range from 1200 to 6000 lumens.  They are switchable 3000K/4000K/6500K. Price ranges from £7.56 for 1ft to £18.96 for 5ft inc tax. Since this is the UK, they operate at 220-240V.
Jonathan

[Jonathan Cross]

Should have written in my previous email that these strip LEDs have a CRI of 80.
Jonathan

[digitaldog]

A high CRI is a decent gauge of how well a light will perform 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 guarantee you the Home Depot bulb has a giant mercury spike and some spectral dead spots. 

A better metric is called CQS (15 very colorful patches). That doesn't tell us about the spectrum, which is even a better way to evaluate the illuminant. 

[alain]

A high CRI is a decent gauge of how well a light will perform 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 guarantee you the Home Depot bulb has a giant mercury spike and some spectral dead spots. 

A better metric is called CQS (15 very colorful patches). That doesn't tell us about the spectrum, which is even a better way to evaluate the illuminant.

Andrew

In the examples that i gave there where quite flat spectra by the supplier and inside reviews.  Both also gave high R9 values, which is quite often lacking in LED's.  Are they perfect? Probably not, but LED's are getting better and it's useful to point to cheap available good LED's.

Alain

[Kyle Jackson]

Yeah at times it feels like drowning in sea of colour rendering "standards" (TLCI, TM-30, SSI...), but I agree the one constant is CRI is always the lowest weight for me. Unfortunately it's also the most prolific in product claims, particularly mass-market products.

That's why independent measurements (non CRI) are so helpful for evaluating how well a particular product might suit our needs/wants. Not easy to find, but I'm certainly finding a lot more data now (and promising products) than I ever did over a decade ago.

Navigating the globally-fragmented and sometimes sketchy niche market seems the main challenge right now. Like I can't even buy the bulbs from the AliExpress link @Czornyj posted above -- can't add more than 1 to cart, and message system to the vendor is broken, no idea why. Just one example, and maybe why some go the DIY route of sourcing their own LED chips and drivers to make their own fixtures. For me I can get the Yujis readily it seems, and I found the Philips Ultra Def in local retail to fill the gap for now (albeit somewhat spikey in reds).

[Lessbones]

Like I can't even buy the bulbs from the AliExpress link @Czornyj posted above -- can't add more than 1 to cart, and message system to the vendor is broken, no idea why. Just one example, and maybe why some go the DIY route of sourcing their own LED chips and drivers to make their own fixtures. For me I can get the Yujis readily it seems, and I found the Philips Ultra Def in local retail to fill the gap for now (albeit somewhat spikey in reds).

why not get the "Norb" bulbs we were talking about in the other thread in the Color Management forum?  they're also clearly using the sunlike emitters, and they're actually cheaper per unit ($20) than the aliexpress ones:  https://www.amazon.com/Full-Spectrum-Performance-Near-Perfect-Rendering-Technology/dp/B07T6JB259?th=1

also it seems like waveform and yuji both have products with violet phosphors/emitters at this point so they're either also using the same sunlike chips or they've figured it out some other way.  I had one bad experience with a company that had some great fluorescent replacement 5000k bulbs with a really nice coverage of the spectrum when I tested one box, but then I ordered 4 more boxes (I think 48 more bulbs) and they all were totally different than the first box with a much worse "cyan gap" even though they have identical model numbers etc.  I'd trust yuji or waveform to have consistent product at this point if you'll be ordering more later on....

[Kyle Jackson]

why not get the "Norb" bulbs we were talking about in the other thread in the Color Management forum?  they're also clearly using the sunlike emitters, and they're actually cheaper per unit ($20) than the aliexpress ones:  https://www.amazon.com/Full-Spectrum-Performance-Near-Perfect-Rendering-Technology/dp/B07T6JB259?th=1

also it seems like waveform and yuji both have products with violet phosphors/emitters at this point so they're either also using the same sunlike chips or they've figured it out some other way.  I had one bad experience with a company that had some great fluorescent replacement 5000k bulbs with a really nice coverage of the spectrum when I tested one box, but then I ordered 4 more boxes (I think 48 more bulbs) and they all were totally different than the first box with a much worse "cyan gap" even though they have identical model numbers etc.  I'd trust yuji or waveform to have consistent product at this point if you'll be ordering more later on....

I'm relying on the data I've been finding, like https://optimizeyourbiology.com/light-bulb-database. I mentioned up-thread that shows the Norbs have high flicker risk so I passed them over. It seems they might have the good LED chips but maybe the drivers are not so much. If it wasn't for that I'd probably try them.

The Waveform products still have a large blue spike so they don't appear to be much better than "generic" rgb LEDs. Screenshots attached from https://optimizeyourbiology.com/light-bulb-database and Waveform's own spec sheet. So the Waveforms are definitely not similar to the Yujis. I'm glad I didn't buy them.

Yeah that component-swapping is the real minefield in the market. Some of these brands and/or makers are marketing one thing but building something else (or it changes), so it's difficult to pick one with confidence. I agree that someone like Yuji appears more trustworthy at this point (and probably justifies the price premium).

[Lessbones]

I was referring to the waveform Absolute series, but it looks like they only have them in strips and modules, no packaged bulb types at the moment

[Kyle Jackson]

I was referring to the waveform Absolute series, but it looks like they only have them in strips and modules, no packaged bulb types at the moment

Interesting, hadn't seen those...  Would be good if they rolled out emitters like that to their other products too.

I'm already picturing some ways to make custom fixtures for my space... 

[Lessbones]

Yuji has already got them in bulb formats etc--  theirs is called "sunwave"  https://store.yujiintl.com/collections/sunlight-technology

[alain]

Interesting, hadn't seen those...  Would be good if they rolled out emitters like that to their other products too.

I'm already picturing some ways to make custom fixtures for my space... 

I like led strips.  Rather easy (with connectors you don't have to solder) and a rather soft light, almost no hotspot.

>€200 for 5 meter is for me quite a lot.

[Kyle Jackson]

Yuji has already got them in bulb formats etc--  theirs is called "sunwave"  https://store.yujiintl.com/collections/sunlight-technology

Yes I linked them above, but not that SunWave line because that one doesn't have the right CCT for me. The NormLite line has the D50:
https://store.yujiintl.com/collections/arts-graphics-lighting/products/normlite-cri-98-d50-5000k-standard-illuminant-led-bulb-iso3664-2000-for-art-studio

[Kyle Jackson]

I like led strips.  Rather easy (with connectors you don't have to solder) and a rather soft light, almost no hotspot.

Yes I think they're very flexible for doing a wider area, and they daisy-chain well. I have a concrete ceiling and limited electrical access so making my own suspended fixtures/panels would be a good option here. My current 2-lamp setup on my work table is often visible in corner of my eyes so I think overhead lighting would work better instead, plus cover move of the room (like @NeilPrintArt 's example above, but with LED strips/bars instead of tube fixtures).

[Lessbones]

Yuji Sunwave 5000K:  https://store.yujiintl.com/collections/sunlight-technology/products/sunwave-cri-98-a19-a60-flicker-free-wellbeing-lighting-10w-led-bulb-3000k-5000k-2pcs-4pcs

[Kyle Jackson]

Yuji Sunwave 5000K:  https://store.yujiintl.com/collections/sunlight-technology/products/sunwave-cri-98-a19-a60-flicker-free-wellbeing-lighting-10w-led-bulb-3000k-5000k-2pcs-4pcs

Thanks, I missed that one since it wasn't in the test database at 5K. That's an interesting alternative if someone wants the dual-temperature option, and doesn't need dimming.

For me their D50 NormLite is a better fit.

[Lessbones]

I recently noticed that these Colorchecker Graflites are quite cheap at b&h-- does anybody have any experience with these/could possibly take measurements of the spectra?

https://www.bhphotovideo.com/c/product/1762058-REG/calibrite_calb151_grafilite_print_view_light.html

Right now I'm using an old GTI lightbox that I retrofitted with LED strips, but it doesn't have different color temperatures and I like how little space these things take up