Explore Scientific 2X 2" Focal Extender

[Mark at Beaufort]

My single highest EP is a 9mm Myraid although I can go higher using my Baader 2.25X Barlow but I don't want to remove the 2"/1.25" Adapter every time.

I could purchase some 1.25" EPs (4mm/5mm) and (6mm/7mm) but I am wondering about buying this 2" ES Extender. Clearly it will add weight in my 12" Dob and 6" Newt but I can overcome this.

I am pretty sure the quality of the ES Extender will be OK which will take my 20" Myraid, 13mm Ethos and 9mm Myraid to a 10mm, 6.5mm and 4.5mm.

My question to any owner is the focus implication - does the Extender create inward focusing problems or outward (extension tube can resolve this) or no focusing problem at all because it stays the same?

[John]

I wonder if the ES 2" 2x Focal Extender is the same as the Meade 2" 2x TeleXtender ?

I've owned the latter for a while and seem to recall that the focal position changed a few mm (inwards ?) but nowhere near as much as it did with barlow of the same specifications.

I've used the ES 1.25" FE and that is very similar to the TV Powermate in use. Again just a small adjustment of focal position but not much at all.

I guess I'm really saying that I don't know for sure about the ES 2" 2x but I suspect the focal position adjustment needed would be minimal.

 

[Mark at Beaufort]

Thanks John. I am hoping to use the 12" Dob tonight (if it does not blow over!!!) and I am going to check the inward position of these 2" EPs. I have millimeter markings on the focuser so I will be able to assess how much inward movement I have available.

[John]

It is very windy here at the moment as well. If I go out I might opt for a skinny refractor instead !

 

[Stu]

Quite apart from the cloud, I don't think I'll brave it tonight!

[Mark at Beaufort]

Well Stu the Dob is out and I have made a list including the SN in NGC 3254.

[John]

Hope you have a good one Mark

 

[Mark at Beaufort]

Well I have had a 30 minute session mainly to determine the inward focusing position of the 9mm, 13mm and 20mm EPs. It appears I have about 5cm to play with so I guess the ES 2" extender will focus OK.

Its a bit windy but the Dob is fairly stable so I will have a session until I get too cold.

[John]

I have put my 130mm refractor out and it's nearly cooled. I was clouded out about 15 minutes ago but there is more sky showing again now. Really quite blustery though.

I was hoping to have a go at Sirius with the 130 but I suspect the wind might stop high powers being much use.