Camera Lenses

[devayaani]

Can anyone please guide me?
I have four SLR Camera lenses from my old Nikon, Elmo cameras. I had kept these lenses although camera bodies were destroyed and these belonged to Film REEL SLR camera.
I have 50mm lenses 8.5- 34 mm MACRO (Elmo camera)
28-80 lens Nikon camera.
The Question is:
Are these useful to construct any optical instrument (gadget such as telescope, for example).
Or these are of no more use and I should simply throw them away?
Thanks for the guidance in advance.

[sandyRoe]

Don't throw them away.

http://www.porters.com/education_station/pdf/LensCompatible.pdf

[Prudie]

I had some old lenses from my Canon SLR and bought a Canon DSLR body and they all work with it.

[jomifl]

Don't throw them away, the Nikon you can Sell on ebay depending especially if it is reasonably sought after. The others may sell if you give an accurate and detaled descrption.

[EDDIE51]

Old SLR lens can be used on modern digital SLRs with an adaptor,sell them on ebay. If you let me know the exact lens I will let you know an idea of value.
I need the details written around the glass of the lens and what camera they were for originally.

[devayaani]

Thanks for everyone answering my query.
I shall contact once I get the details of these lenses.
Very much appreciated.
Devayaani

[EDDIE51]

Is this your lens
http://www.ebay.co.uk/itm/NIKON-ZOOM-NIKKOR-28-80MM-F3-3-5-6-G-MINT-/370955591580?pt=UK_Lenses_Filters_Lenses&hash=item565ead1f9c
If so they sell for £25 to £40