| Author | Message | ||
     David von Boisman (david_von_boisman) Intermediate Member Username: david_von_boisman Post Number: 19 Registered: 2-2006 |
Dear Xavier, I'm unfamiliar with the installations of other suppliers, but I know that FOSS has sold a lot of instruments in Malaysia and some of them are probably installed at universities and might be accessible to you. You can contact the distributor, they should know exactly where to look: Matrix Analytical Technologies Sdn Bhd 43-45B, Jalan SS 25/2 Taman Bukit Emas 47301 Petaling Jaya, Selangor Darul Ehsan Malaysia Tel: +603 7880 8289 begin_of_the_skype_highlighting��������������+603 7880 8289������end_of_the_skype_highlighting +603 7880 8289 Fax: +603 7880 8232 [email protected] | ||
| Chia (xaivier) Junior Member Username: xaivier Post Number: 6 Registered: 4-2010 |
Hi, Boisman, The purpose of my research is to predict the internal quality of fruit. In this research, I need to collect spectra from fruits and its reference quality value(SSC) before calibrate a prediction model. I am from Malaysia. My university has "Lambda 900" UV NISINIR spectrophotometer. But last time I went and meet the researcher of this spectrophotometer, he said this spectrophotometer was not suitable for my research. Therefore, I really hope I can buy a low cost Vis/SW-NIR spectrometer for my research. | ||
| Chia (xaivier) New member Username: xaivier Post Number: 5 Registered: 4-2010 |
Hi, Zinir, Thanks for your suggestion. But I can't get your email. My email is [email protected]. | ||
| David von Boisman (david_von_boisman) Intermediate Member Username: david_von_boisman Post Number: 18 Registered: 2-2006 |
Hi Xavier, Whats the purpose of your research? Unless you really want to learn how to build a NIR instrument, I would strongly advice against building something from loose parts. I used to work for one of the major suppliers of NIR instruments for FOOD/AGRI applications, and we typically had a team of 20+ persons working for several years on the design of an instrument, that's the sort of resources you need to assure that you get decent noise levels, avoid stray light, and get any usable data out of the setup. There is a reason why quality instruments are expensive. If you have limited funds id suggest trying to find a lab that already has a good NIR instrument and make a deal to use that instrument for your research. That also brings you the added benefit that you can discuss calibration issues etc with someone who has some experience of the instrument and the software in question. If you tell us your location someone on this list may be able to advice you on a suitable lab. | ||
| Ian Goodyer (zinir) Junior Member Username: zinir Post Number: 8 Registered: 5-2006 |
Chia, Halogen light sources all have a very similar spectral response - they are all black bodies and only really vary because of small changes in their colour temperature. The key thing to look out for, besides price, when choosing a halogen source for spectroscopy are i) brightness (brighter is better for deeper penetration into fruit and for a better signal to noise) ii) stability (essential to make good reliable consistent readings for chemometrics). If you drop me a personal message with your email address I can send you more info. Ian | ||
| Chia (xaivier) New member Username: xaivier Post Number: 4 Registered: 4-2010 |
Thanks, Kerry walsh. Your suggestion is utmost useful for me. For cheaper halogen lamp, besides its spectrum range, what is your suggestion about its power(watt) and its voltage? About "add some optics", do you mean fiber optic? Thank you very much. | ||
| kerry walsh (walshk) Junior Member Username: walshk Post Number: 6 Registered: 2-2007 |
Hi Venky yes, it does seem unlikely, but theres the benefit of working with the low absorptivity Herschel region (there are plenty of disadvantages on other fronts!). Also, fruit (minus skin) can have remarkably good transmission even at visible wavelengths...place a skin orange on a torch in a darkened room for an interesting effect. As mentioned, there are now a number of commercial manufacturers of both in-line (fruit conveyor line) and in-field (handheld) units, mostly interactance (partial transmittance), a few full tansmission, a few reflectance geometries. K K | ||
| venkatarman (venkynir) Senior Member Username: venkynir Post Number: 108 Registered: 3-2004 |
Hi Kerry walsh this allows assessment to some depth (typically 10-20 mm), and even full transmission for some fruit please think of this statement . What about energy level at (700-1100 nm) ? I have seen good application for liquids not semi-solids . I have doubt about 10-20 mm ? | ||
| kerry walsh (walshk) New member Username: walshk Post Number: 5 Registered: 2-2007 |
Dear Chia, Generally non-invasive work with fruit targets use of the Herschel wavelength region (700-1100 nm)...with appropriate optics (eg lamp/sample/detector geometry) this allows assessment to some depth (typically 10-20 mm), and even full transmission for some fruit. For $3000 you can acquire a Si detector (e.g. Zeiss MMS1 or Ocean Optics SD 4000) and then couple it to a cheap halogen lamp on a stable DC power supply, add some optics and a controlling PC and enter the game. However, there are a number of fruit specific spectrometer systems available, both for on-line sorting (at up to 10 pieces of fruit per second) and handheld (for use in orchard). Of course these cost multiples of the spectrometer engine alone. Im happy to give a range of specific (dedicated fruit specific) supplier info if you wish to contact me at [email protected], or you might search the recent literature, eg walsh, kawano, zude, nicolai, mcglone,to name a few. Good luck. | ||
| Chia (xaivier) New member Username: xaivier Post Number: 3 Registered: 4-2010 |
Thanks for Venkatarman. After consider Fernando suggestions (I think these questions are very useful for me) I think about using 400-1100nm but haven't considered about its resolution. 1. The parameter that I want measure is SSC of fruit 2.- However, I have no idea about how to determine normal chemical range for SSC. 3.- I want to get the spectrum non-destructively, the area of measurement is surface of fruit. 4.-I not very sure about the sample is homogeneous or not. And I not very clear about this consideration. 5.-I need NIR prediction only via PLS calibration Finally, do you have any PhD dissertation related to NIR? Thanks in advance. | ||
| venkatarman (venkynir) Senior Member Username: venkynir Post Number: 107 Registered: 3-2004 |
HI xaivier ! I have done intensive web search and study of NIRS spectrometer .First you make-up your mind range and resolution needed .That is most important .Then as Fernando suggestion list out your need .Finally budget in to the picture . | ||
| Gabi Levin (gabiruth) Senior Member Username: gabiruth Post Number: 39 Registered: 5-2009 |
Dear Chia, Besides all the important points people raised, and I will even assume now that you have more than 3000 - when you say - inner quality of fruits - how deep is inner - is it just below the skin - or is it far deeper? If deeper - how much? Please recognize, almost without exception - the depth of penetration of NIR is limited, and with fiber based tools - it is probably below 1 mm. Once we know the goal, it becomes possible to look for the tool, but just so you don't raise your hopes too high, 3000 is truly exceptionally low. Gabi Levin | ||
| Chia (xaivier) New member Username: xaivier Post Number: 2 Registered: 4-2010 |
Hi, Fernando, Thanks for your suggestions. I agree with you for not talking about trademarks here. However, I still hope can get some suggest about low cost NIR spectrometer to complete my research. Basically, I want to build a SSC prediction model of various fruits. After read through some paper, I found most of them used visible and short-wave NIR to this kind of research. And I also got a quite satisfied result by using visible to short-wave NIR spectrometer in my previous research. (400-1100nm) However, I do not have enough funding to own that kind of spectrometer. The new budget for me is around $3000.00 USD only. As a result, I should use this limited fund to buy a spectrometer, a light source, a interface software and fiber optic before carry out this research. Is it possible? I will be grateful to hearing precious suggestion from you. (Do drop an email to me about the suggestion price, specification and technical documents at [email protected] if it has conflict of interest here.) | ||
| Fernando Morgado (fmorgado) New member Username: fmorgado Post Number: 3 Registered: 12-2005 |
Dear Chia : I think this discusion group is not for talk about trademarks, wich is better, etc. Always the better instrument depend of the aplication. For define a usefull Instrument you need know some thinks. 1.-Wich parameter do you want measure 2.- Wich is the normal chemical range for that parameter, in order to see it is possible measure by NIR 3.- Wich is the area of the sample to measure? 4.- The sample is homogenius or not? 5.- You need NIR prediction or only need a qualitative analisys ( spectra) When you have this answers you will know the wavelenght range do you need for your aplication. You know if realy the aplication work in NIR. And you can buy a Instrument with the correct sample holder. The better is look in internet some aplication paper similar do you want, don�t see the trademark used, see the spectra range and type of sample holder. After this you can start to quote and to buy a not expensive Instrument. regards Fernando | ||
| Gustavo Figueira de Paula (gustavo) Junior Member Username: gustavo Post Number: 9 Registered: 6-2008 |
Xaivier, What's your budget? It's the first parameter to stablish a boundary to put off (or in) hundreds of available espectrometers available in the market. You can contact me privately, I've been quoting NIR spectrometers for months. [email protected]. | ||
| Chia (xaivier) New member Username: xaivier Post Number: 1 Registered: 4-2010 |
Due to the limited funding of my research, I hope can buy a cost effective NIR spectrometer for my research about internal quality of fruit. Please give me some guidance about it. Thank you very much. |