BST explorer 8mm twist-up eyecup?

[moffer]

Much appreciated if someone can tell me how to adjust the eyecup on my son's new eyepiece. Have tried twisting (anti-clockwise) and twisting and pulling up at the same time, but it won't budge either way. Could be I'm being too careful (or quite likely getting the procedure wrong) but am obviously concerned about causing damage.

[AndyWB]

It should just twist - you shouldn't need to pull at all. I'm pretty sure anti-clockwise is correct, too. I seem to remember mine were a little stiff at first, but having been opened and closed are now okay; there is some lube in there.

Oh, and you just need to twist the very top rubber bit - above the top coloured metal divider thing. I thought it looked a little confusing because the body lower down has some little dents that made it look like you should twist the main bit the body.

[russ.will]

They're pretty sturdy, so don't be too scared.From memory, it's anti-clockwise and the pitch is course, so the full extension of 8-10mm is achieved in about 1/2 - 3/4 of a turn.

It is conceivable yours is stuck, but it would be the first one I've heard of.

Russell

[andrew63]

Hi moffer - you just turn the bit above the green ring anti clock - it should move easy - this is mine and you can see it slighty raised. Hope that helps.

andrew

[Stargazer_00]

Think of it like undoing a screw top bottle.

[moffer]

Thanks very much all.

I did think it was probably a screw fit that's why i went anti-clockwise, and it was the bit above the coloured ring that I tried unscrewing. Obviously need to apply a bit more pressure - it's definitely a bit tight though. The eyepiece is down my son's house at the minute, I'll phone him when he comes home from work so he can give it another go - that's if he's got enough strength left after a 12 hour shift. Will post results later.

He tried the bst out for the first time the other night and managed brief views of the moon and jupiter through the odd gap in the clouds. He reckoned it was miles better than the 10mm stock eyepiece that comes with the skywatcher 200p, and managed to see some structure to the two main jovian belts for the first time. Even his partner was impressed, and believe me that takes some doing, she just couldn't see what all the excitement was about previously.

[Stargazer_00]

that's probably an advanced warning not to look through ultra widefield eyepieces until your bank ready the biggest, most obvious difference is the increase in AFOV between a plossl and a BST.

[rwilkey]

Hi Moffer, it should twist-up OK, and another thing to add, the BST's are best used with the eyecup fully up for comfortable viewing, otherwise they can black out, though this is not an inherent problem with this ep.

[moffer]

Sorted!.... my son said it was a tad tight but didn't require much effort to unscrew - guess I must be getting old and feeble.

Thanks Robin, my son was getting black outs when he used it the other night.

Cheers everyone.

[russ.will]

Sorted!.... my son said it was a tad tight but didn't require much effort to unscrew - guess I must be getting old and feeble.

Good to know he's about for when you get beaten by a pickle jar.

Russell

[moffer]

Good to know he's about for when you get beaten by a pickle jar.

Russell

Don't need him to open pickle jars - my wife manages just fine.

[Stargazer_00]

lol