Fluor objectives contain fewer lenses as compared to apochromats and therefore 
they 
have a higher transmission at all wavelengths. Fluor objectives does not have 
the same 
good color correction as apo lenses and they are often called semiapochromats 
or superachromats.

Yours,

Göran Ocklind, Ph.D.
Uppsala Univ, Pharmacy /Div  Pharmaceutics
Box 580, 751 23 Uppsala, Sweden
http://www.farmaci.uu.se/~galenisk/
-----Ursprungligt meddelande-----
Från: Tony Collins <[log in to unmask]>
Diskussionsgrupper: bit.listserv.confocal
Till: [log in to unmask] <[log in to unmask]>
Datum: den 24 april 1998 11:26
Ämne: fluor vs. planapo


>Hello all
>this argument may have been run before. I apologise in advance if it induces
>groans from regular readers of the list.
>
>Are there any opinions (!) on whether fluor or plan apo objectives are more
>suited to imaging fura2 and indo1.
>
>Is it fair to say that a fluor objectives, compared to a plan apo hi NA 
objectives,
>have higher transmission at shorter wavelengths at the expense of longer
>wavelengths ?
>
>If so, since the UV excitation intensity can be increased (e.g. lower ND 
filters),
>does the longer wavelength emitted light which cannot be easily increased
>(swap cameras?) take "priority".
>
>Would this mean a hi NA plan apo is better than fluor objectives for imaging UV
>excited dyes? Or is there problems with chromatic abberation of the excitation
>light that take priority? If so, is this more important for confocal rather 
than
>conventional fluorescence?
>
>Have I missed the point of fluor objectives?
>
>I accept that this point is based on the assumption the UV intensity is not
>maxed out!
>
>Thanks for all comments.
>
>Tony Collins
>
>Dept. Neurobiology
>The Babraham Institute
>Babraham Hall
>Babraham
>Cambridge CB2 4AT
>UK
>
>tel. +44 (0) 1223  832312
>fax. +44 (0) 1233  836614