Well you could use the terrestrial eye piece for astronomy and I suppose it'd be similar to using a modern spotting scope for astronomy but you'd lose light when viewing faint astronomical objects due to passing through more glass.

@projector7141

9 ай бұрын

You can just remove the erector tube cartridge to make it astronomical.

Dear Graham! I found a Bardou & Son, Paris 3 inch telescope. Seems it has the same cell type. But I could not get the cell pushed out of the main tube.

@JenhamsAstro

2 жыл бұрын

Hello Mike, that’s interesting. Is there another way of removing the lens? Perhaps it has a screw thread?

@mikemopar9989

2 жыл бұрын

@@JenhamsAstro No screw thread . I will try to get it out with a small hammer pushing it out at the end of the lens cell. .

@JenhamsAstro

2 жыл бұрын

@@mikemopar9989 Care required!

@mikemopar9989

2 жыл бұрын

Hi Graham. I have send you some pictures on KZread of the Bardou telescope!@@JenhamsAstro

4:10 Can I ask what type of grease is used on the focuser, please?

Dear Graham! i found an unsigned 18th century scope that looks like a Dollond scope. Does all early Dollond scopes have 2 achromatic lenses?mine has only one front lens.

@JenhamsAstro

Жыл бұрын

Hi Mike, a good question which I am not expert enough to answer. Dollond was of course famous because of his patent for achromats, and their subsequent manufacture, but he was in business before this date. I’m not sure if he produced singlets in this period.

Hello Graham! i found 3 old british brass telescopes here in Germany , one of Dollond, one Scout scope from WW2, and a very long ( 4 ft.) 114 cm with a wooden body. no engravings on it. Never seen such a long 4 draw brass scope. Have you any idea?

@JenhamsAstro

3 жыл бұрын

Hi Mike, I agree that is a long tube and I wonder if the image suffers as a result. Normally the ones I've seen are less than 100cm. Just for comparison there are some examples with descriptions on this site: www.scientificcollectables.com/page_telescopes.htm

@mikemopar9989

3 жыл бұрын

@@JenhamsAstro Thank you. It must be an old naval scope i think. it has a 68mm front objectiv lens.and a wooden body. I found it in an antique shop in the german seaport Leer.

Wow!!!!!

☺👍