CLARIFICATIONS AND RESPONSES IN THE PRE BID MEETING HELD ON 19TH AUGUST 2013 IN OUR COMMITTEE ROOM FOR THE PROCUREMENT OF FULLY MOTORIZED INVERTED FLUORESCENT MICROSCOPE
File No:PUR/IMP/030/13
Description of Item:FULLY MOTORIZED INVERTED
FLUORESCENT MICROSCOPE
Answers to queries
OLYMPUS
Point No-1- We would like to suggest 10nm step size z focussing, 8 position fluorescence turret is available without any prize difference. Why restrict to 6 position?
Answer:We need 6 position turret with 25 nm step size z focussing. You are free to quote for higher configuration.
Point No 4- Please reconsider whether phase contrast is really required? Phase is not required if DIC is offered. If required please clarify those objectives (whether 10X and 20X)
Answer:We need both DIC and phase contrast since both cells on glass surface and plastic needs to be imaged. Phase objectives from 10X to 40X and DIC and fluorescent (40X and 100X)
Point No-8- Better to go for left side port with 100:0, 50:50 and 0:100 light path rather than 80:20. Trinocular head is not required at all.
Answer:We require motorized left and right light path for camera with 100 % transmission.
Point No 9-Please consider a better camera with -30 absolute cooling with more than 60% quantum efficiency. This is because when you have a very good microscope, why compromise on camera?...Not much prize difference.
Answer:Additional camera such as CCD/EMCCD may be offered as optional with their specifications.
Point No-12- Mercury 130 Watts will give you more than 1500 hrs life time. Please clarify either Mercury or Metal Halide.
Answer:We need mercury light source.
CARL ZEISS
Point No 1: Z resolution of 25 nm: Zeiss can offer you 10 nm resolution
Answer:We need 6 position turret with 25 nm step size z focussing. You are free to quote for higher configuration.
Point No 2Adaptive focus or PFS: same can be upgraded at a later date
AnswerTime lapse imaging requires this and we require it now itself
Point No: 4Please specify your application
AnswerMicroscope is meant for both phase and DIC imaging.
Point No: 8We recommend (0% camera, 100% Eye: Camera 100%, 0% Eye) instead of 80:20. Specification for 4 ports: we suggest 3 ports Left, Right & Front port or two ports (Left & Right)
AnswerWe require motorized left and right light path for camera with 100 % transmission.
Point No: 9We suggest monochrome CCD camera with Peltier based cooling (1.4mega pixel) firewire. Chip size (8.9mmX6.7mm)
AnswerAdditional camera such as CCD/EMCCD may be offered as optional with their specifications.
Point No: 10System software like co-localization FRET, FRAP & FLIP: FRET (quantitative), FRAP & FLIP: we suggest FRET modulealone.
Answer The software should support all the applications as shown in the specifications.
Point No: 11We suggest you to go in for APOTOME (Optical section) or Optic grid module instead of simple 3D deconvolution.
AnswerWe don’t require APOTOME.
Point No: 12Please mention whether you need mercury light source or metal halide illumination.
AnswerWe need mercury light source.
NIKON
Point No: 1-We wish to state that minimum Z resolution resolvable on any optical microscope is 750nm or so and anything lesser than this is more likely to be over sampled and not improve any axial resolution.
Answer:We need 6 position turret with 25 nm step size z focussing.
Point No: 2- Even if there an experiment of cells division or for the study of morphological changes happening over a period of time say a duration of 60 minutes or more on a cell PFS system is very much essential for the system to track the focus of the sample over this time period and PFS System on a Nikon inverted microscope does track this changes in focal point and keep the system always in focus. This is becoming an essential part of a fully automated inverted microscope nowadays.
Answer:We stick to the points as shown in our original specifications.
Point No: 4- It is always preferred choice of the phase objectives from 10X to 40X and a dedicated set of objectives for both DIC and Fluorescence work from 40X to 100 X as a general rule.
Answer:We need both DIC and phase contrast. Phase objectives from 10X to 40X and DIC and fluorescent (40X and 100X)
Point No: 8- If an inverted microscope is purchased then the choice of light ports or different or varied needs, later on or as a future up gradation need to be considered and in this aspect the Ti-E Nikon motorized inverted microscope fulfils with motorized with light path switching. It even has an option of a bottom port where the camera gets connected directly to the microscope and this arrangement does provide for chromatic aberration free light path to the camera as this does not involve prism /mirror in the system. The motorized microscope can never be upgraded at sight later on if needed be as this warrants a lot of changes to be done structurally and would entail the unit to be sent back to the manufacturer for the changes.
Answer:We require motorized left and right light path for camera with 100 % transmission.
Point No: 9-We do have a camera from Nikon that more or less matches specifications asked for. However for a better picture quality if a camera is made to cool to -20 degrees or even sometimes lower than this (-45 to -55degree) then the effective photon collection of the CCD camera improves drastically as the thermal noise that would have been induced that would have been suppressed and this greatly enhance the effective picture quality or video movie.
Answer:Additional camera such as CCD/EMCCD may be offered as optional with their specifications.
LEICA
Point No: 3- we request you to mention the number of magnification changes with magnification ratio with motorization (we at Leica can provide 3 position motorized magnification changer with 1X,1.5X/1.6X and 2X magnifications)
Answer:We need both DIC and phase contrast. Phase objectives from 10X to 40X and DIC and fluorescent (40X and 100X)
Point No: 7-we request you to change to motorized 7 more position condenser (as it is mentioned in the specification that phase contrast is required for 10X, 20X and 40X objectives and DIC is required for 4X/5X, 10X, 20X, 40X, 60X/63X and 100X oil objectives, a normal six position condenser can accommodate only 3 position for phase, 2 position for DIC and 1 position would be reserved for bright field. Hence by increasing the slot from 6-7 in condenser, you would be able to incorporate the phase contrast rings and DIC prisms together in the condenser and no need for the user / engineer intervention to change them ring and prisms at the different time of application.
Answer:We need 6 position condenser as mentioned in the specifications. You are free to quote for a higher configuration.
Features to be included:
1) Motorized analyser/polariser to be engaged / disengaged as per bright field /DIC/Fluorescence contrast methods.
2) Motorized diaphragm to reduce the fluorescent intensity of fixed steps for both eyepiece field of view and camera field of view (Clarification by including this the user would have the flexibility to expose/excite only the desired region of interest at centre of field in different fluorescence applications especially when doing FRET, single cell analysis etc).
Answer:We are not interested to change the specifications at this point.
The tender specification stands amended to the extent as given above.
Stores & Purchase Officer