Unsupported photometric type IES file: 2

Use this forum for general user support and related questions.
Forum rules
Please upload a testscene that allows developers to reproduce the problem, and attach some images.
Post Reply
Philstix
Posts: 13
Joined: Sun Feb 04, 2018 8:48 pm
Location: Brisbane, Australia

Unsupported photometric type IES file: 2

Post by Philstix » Fri Feb 23, 2018 7:25 am

I'm curious about an IES file I downloaded from GE for a billboard floodlight.

When I tried to load the IES file in an Emission node I received the error "Unsupported photometric type IES file: 2". I looked through the LuxCore source and headers, and found:

Code: Select all

	const size_t vpos = templine.find_first_of("IESNA");

	if (vpos != string::npos)
		m_Version = templine.substr(templine.find_first_of(":") + 1);
	else
		return false;
and

Code: Select all

if (data.m_PhotometricType != PhotometricDataIES::PHOTOMETRIC_TYPE_C)
		throw runtime_error("Unsupported photometric type IES file: " + ToString(data.m_PhotometricType));
and

Code: Select all

	enum PhotometricType {
		PHOTOMETRIC_TYPE_C = 1,
		PHOTOMETRIC_TYPE_B = 2,
		PHOTOMETRIC_TYPE_A = 3
	};
so I assume only 'TYPE_C" IES files are supported, and the error arose because the first line of the IES file is "IESNA:LM-63-2002".

This isn't a big deal, there are lots of IES files to choose from, but I just wondered if I understood the error correctly.

This is the information at the start of the file:

Code: Select all

IESNA:LM-63-2002
[TEST]17071330 17071331 17071430
[TESTLAB] GE LIGHTING SOLUTIONS-HENDERSONVILLE NC USA
[ISSUEDATE] 12/13/2017
[MANUFAC] GE LIGHTING SOLUTIONS
[LUMCAT] EFM101_CCT3740________
[LUMINAIRE] EVOLVE FLOOD EFM101
[DISTRIBUTION] TYPE 3
[LAMPCAT] LEDs
[LAMP] LED
[OTHER]
[MORE]
[_DRIVE_CURRENT]
[_CCT] 4000K
[_CRI] 70
[_ABSOLUTELUMENS] 15000
[_SYSTEM_WATTS] 141
[_ACCESSORIES]
[_SEARCH_SOURCETYPE] LED
[_SEARCH_CRI] 70
[_SEARCH_COLORTEMP] 4000K
[_SEARCH_APPLICATION] Outdoor, Architectural, Area, Automotive, Commercial, Dock, Educational, Facade, Government, Healthcare, Hospitality, Hotel, Industrial, Landscape, Library, Manufacturing, Office, Parking, Parks, Prison, Recreation, Retail, Sign
[MORE] Site, Street, Utility, Walkway, Direct, Flood, Security, Wall Wash, Wet Location
[_SEARCH_MOUNTING] Knuckle, Pole, Wall
[_SEARCH_CERTIFICATION] UL
[_SEARCH_CLASSIFICATION] IP66
TILT=NONE
1 -1 1 73 73 2 1 1.06 0.54 0
1 1 141


(I was going to attach the file but the 'Add files' function wouldn't let me attach an IES file or a text file)

P.S. Ok I've attached the zipped IES file:
EFM101_CCT3740________.IES.zip
(13.42 KiB) Downloaded 165 times
Last edited by Philstix on Fri Feb 23, 2018 8:42 pm, edited 1 time in total.

User avatar
B.Y.O.B.
Developer
Posts: 4125
Joined: Mon Dec 04, 2017 10:08 pm
Location: Germany
Contact:

Re: Unsupported photometric type IES file: 2

Post by B.Y.O.B. » Fri Feb 23, 2018 7:35 am

Philstix wrote:
Fri Feb 23, 2018 7:25 am
(I was going to attach the file but the 'Add files' function wouldn't let me attach an IES file or a text file)
You can zip it and attach then.

Philstix
Posts: 13
Joined: Sun Feb 04, 2018 8:48 pm
Location: Brisbane, Australia

Re: Unsupported photometric type IES file: 2

Post by Philstix » Fri Feb 23, 2018 8:43 pm

B.Y.O.B. wrote:
Fri Feb 23, 2018 7:35 am
You can zip it and attach then.
Done.

Philstix
Posts: 13
Joined: Sun Feb 04, 2018 8:48 pm
Location: Brisbane, Australia

Re: Unsupported photometric type IES file: 2

Post by Philstix » Fri Feb 23, 2018 9:32 pm

After further research it seems my understanding was completely wrong ( :lol: same old, same old...)

I found a link to the IES file format documentation at http://lumen.iee.put.poznan.pl/kw/iesna.txt. Digging through that document indicates that the critical part of the IES file is the first line of numbers:

Code: Select all

1 -1 1 73 73 2 1 1.06 0.54 0
and the Photometric Type is indicated by the 6th number in the line. In the case of the GE file producing an error, that number is '2'.

I compared it to the corresponding line in a working IES file from Erco:

Code: Select all

1 -1 3.876 73 73 1 2 0.195 0.025 0.002
where the Photometric Type is '1'.

So the upshot of all this is that I need to restrict myself to IES files that indicate '1' as the 6th number in the first line of digits after the keyword entries.

Reading through the IES format document is quite illuminating (sorry!). It makes the point that the IES photometric types are poorly defined and that there is no international standard. The Photometric Type 1 is the standard for U.S. manufacturers, but many light manufacturers use other types.

Philstix
Posts: 13
Joined: Sun Feb 04, 2018 8:48 pm
Location: Brisbane, Australia

Re: Unsupported photometric type IES file: 2

Post by Philstix » Fri Feb 23, 2018 11:57 pm

After still more searching, I found a good explanation of the different photometric types in IES files at http://www.ransen.com/photometric/Type- ... -Files.htm. This indicates that IES Type B - the type that caused the error in LuxCore - is used for floodlights, so perhaps this could make it difficult to use IES-based floodlights in LuxCore.

The same site also contains information on converting between IES type B to type C - the type that LuxCore requires - at http://www.ransen.com/photometric/Conve ... Type-C.htm

The solution involves downloading and installing a free Windows program 'LiteStar 4D Photoview Open' from https://www.oxytech.it/software/photoview.asp. The program requires .Net 4. I installed the program and .Net 4 into a VirtualBox Windows XP machine. I followed the conversion instructions from http://www.ransen.com/photometric/Conve ... Type-C.htm, and the converted IES file works in BlendLuxCore without a problem. :D

User avatar
B.Y.O.B.
Developer
Posts: 4125
Joined: Mon Dec 04, 2017 10:08 pm
Location: Germany
Contact:

Re: Unsupported photometric type IES file: 2

Post by B.Y.O.B. » Sat Feb 24, 2018 7:28 am

If this converter code is open source we could integrate it in the addon or Luxcore.
Thanks for documenting your findings by the way, this will be helpful for others.

Philstix
Posts: 13
Joined: Sun Feb 04, 2018 8:48 pm
Location: Brisbane, Australia

Re: Unsupported photometric type IES file: 2

Post by Philstix » Sat Feb 24, 2018 10:14 pm

B.Y.O.B. wrote:
Sat Feb 24, 2018 7:28 am
If this converter code is open source we could integrate it in the addon or Luxcore.
That would be nice, but I couldn't find any reference to source code. I think they use the term 'open' to mean free, not open source.

Unfortunately IES (Illuminating Engineering Society) seems to be strongly focussed on profit. Even a pdf of the file format specifications for IES LM-63-2002 is only available at a cost of US$20 (https://www.ies.org/store/measurement-t ... tric-data/).

I have also realized that some manufacturers (eg GE, Philips) create non-compliant IES files anyway. Data that should be contained in a single line (according to the original IES file format spec) is spread over several lines, so it is necessary to read each angle and candela value one at a time instead of all in one line. It shouldn't be particularly difficult (famous last words...) so I'll see if I can come up with a suitable parser, but the IES 'standard' is a bit of a mess, so don't hold your breath :?

And if that isn't enough, the IES file format has been acknowledged by Ian Ashdown - who wrote the original parsing reference back in 1998 - as antiquated and unsuited to modern light sources (http://agi32.com/blog/2017/04/27/rethin ... le-format/).

KapaPi
Posts: 1
Joined: Tue Aug 31, 2021 10:10 am

Re: Unsupported photometric type IES file: 2

Post by KapaPi » Tue Aug 31, 2021 10:22 am

Hello,
Recently I've been using LuxCoreRender along with Blender 2.92.0 to do some archviz. I would love to be able to use .ies files, as it saves me a lot of trouble setting up a spotlight. After I attach an .ies file (either to a point lamp or an emission node), switching to Render View mode gives me a flat grey silhouette of my model and I get the message:
"Error: | Invalid IES file in property xxxxx"

I tried the aforementioned steps (thank you, by the way, all community effort is appreciated), but I didn't have any luck. Note that, I happen to have some .ies files that work just fine, but the very specific ones from a certain manufacturer just won't do. After actually inspecting the original manufacturer's .ies file, it turns out it was already type C (6th digit: 1). What gives?

And on that note, I was meaning to ask: Is BlendLuxCore different to LuxCoreRender? I'm confused, is the above solution not applicable to my LuxCore + Blender 2.92 setup?

User avatar
Dade
Developer
Posts: 5524
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Unsupported photometric type IES file: 2

Post by Dade » Tue Aug 31, 2021 10:45 am

If you post the problematic .ies file, we may be able to say more.
KapaPi wrote:
Tue Aug 31, 2021 10:22 am
And on that note, I was meaning to ask: Is BlendLuxCore different to LuxCoreRender? I'm confused, is the above solution not applicable to my LuxCore + Blender 2.92 setup?
Your .ies may just have a different problem. As written before, not every IES file fully follow the standard and/or our parse may be no able to read them.
Support LuxCoreRender project with salts and bounties

User avatar
fluxfish
Posts: 8
Joined: Thu Aug 09, 2018 9:27 pm

Re: Unsupported photometric type IES file: 2

Post by fluxfish » Tue Aug 31, 2021 8:09 pm

  • maybe http://photometricviewer.com/ IESViewer helps with finding the origin of the problem (?), you can also export to .ldt and then .ldt back to .ies, maybe it helps
maybe there is room for improvements in LuxCore, don't exactly know, Info-URLs I have so far

Post Reply