What to do about eyepieces?

[jlowdo]

Tinker, that just confuses the hell out of me! i don't even want to pretend to know what is going on there!!

YKSE, so to my point above,if i bought the aspheric 36 and cancelled the TV 32, as long as i have 1.25 i would gain/lose nothing, but would have increased FoV if/when i upgraded the diagonal?

again, sorry if these questions sound very basic, but i have a window ( birthday time ! ) to buy a couple more bits now, so i am intending to make the most of it...

cheers

James

[Rockrae78]

Honestly, I'm not really sure if it works that way.  36mm refers to the focal length of the EP, not the FoV, so in my mind, even at the 1.25" setting, its still a 36mm EP (something to do with the length between the lenses in the actual EP - the 1.25 barrel doesn't have any lenses in it).  

It does narrow the FoV. I did some calculations before I bought it, but maths has never been my strong point so I'm not sure that my calculations were correct.  Maybe someone else would have a better idea about that?

[Rockrae78]

The 36mm won't fit in a 1.25" adapter, 2" only.....using adapters to reduce from 2" to 1.25" i'm not sure what would happen.....

The 36mm comes with a 1.25" adapter, so you can use this to fit it into a 1.25" diagonal.

[YKSE]

Yes, James, you will gain FOV only if you uppgrad to 2" diagonal with 36mm Aspheric.

[jlowdo]

If you want to stick with 1.25", the TV 32mm Plossl is about as good as it gets. It will show you the maximum field that the 1.25" format can give and with a comfortable (perhaps even a bit long) eye relief.

A 2" diagonal and 2" widefiled EP's would be able to show a much wider field but at a significantly higher price.

This is sort of what i mean... if the only thing i intend to buy at the moment is the widest (beginner) EP, without replacing the diagonal, which i can do later and then stock up on bits to accommodate that... then this is ok?

the 36mm Hyperion aspheric would require a 2".. is that correct?

My Brain hurts

thx

James

[jlowdo]

The 36mm comes with a 1.25" adapter, so you can use this to fit it into a 1.25" diagonal.

ok, so i was wrong about that. it will work fine with the stock diagonal then?

ta

But as per RikM, would it give me better/equal options with the stock components? sorry guys !

Cheers

[RikM]

the 36mm Hyperion aspheric would require a 2".. is that correct?

The Baader 36mm can be used in an 1.25" diagonal and it will give you the correct magnification for a 36mm EP, but it will be vignetted at the edge, you won't see the whole image, only the centre part. It will show you the same field of view that you would get with the TV 32 but at a lower magnification, so the image circle will appear smaller.

If you intend to change to 2" in the not too distant future, it may be better to get the Baader 36mm now and put up with the stopped-down image for a while. If you are going to stick with 1.25" for a good long time, then I would go with the TV 32.

[jlowdo]

i.e... if i changed my order from the TV32 to the 36 Baader, it would be pretty similar at the moment, but if i changed the diagonal it would then be a better option?

funny, i am used to the forums i use becoming quiet by this time of night, but i guess for you guys this is pretty normal

[Rockrae78]

ok, so i was wrong about that. it will work fine with the stock diagonal then?

Yes, it will, but only if you screw in the 1.25" adapter for this EP.  It won't fit with the 2" barrel in use instead.

[YKSE]

36mm aspheric will work with stock 1.25" diagonal, but it will the same amount of skyas the stock 40mm EP, and just a little more the LVW 22mm. just as RikM put it.

[jlowdo]

thanks RikM... gives me a few hours to ponder on it. so basically, the TV32 is better for me 'currently', the 36 will be similar ( bearing in mind i'll probably not notice the difference with my total lack of experience ) but would come into its own a bit more if i upgraded?

maybe..

[RikM]

i.e... if i changed my order from the TV32 to the 36 Baader, it would be pretty similar at the moment, but if i changed the diagonal it would then be a better option?

I think so yes. I have used a TV32, but not the Baader. I did some reading up on it a while ago for a friend with an 8SE though. It will be very similar to the 40mm that came with the scope, unless you upgrade to a 2" diagonal. The TV32 would show the same area of sky, but at a high mag / larger circle so it gives a different feel to the 40mm. ( I have a 40mm TV plossl as well).

funny, i am used to the forums i use becoming quiet by this time of night, but i guess for you guys this is pretty normal 

I guess a lot of people have just put the scopes away and are checking the forums before turning in for the night. That's certainly my case.

[Rockrae78]

I went a bit over the top with the baader click locks, there a really good addition for screwless working in the dark with cold fingers....

The EP set-up

This really made me smile... You couldn't get away with this on the CPC800 if you stick with the fork mount (as i have done)... not enough clearance when scope is pointing at zenith!

[Ags]

What a confusing thread!

The hyperions are 1.25" EPs. You can unscrew the first lens group to turn them into 2" EPs, but there is no point in doing so because they do not give you more FOV than you could just get with a 1.25" EP, and they are poorly corrected, because you removed the first lens group, which is a corrector.

The aspherics are 2" EPs. They have an adapter that lets you put them in a 1.25" barrel, but doing this drastically reduces the FOV.

[YKSE]

James, if you find 22mm LVW or the stock 40mm show big enough sky in the scope, then a 32mm TV plössl will be a very good addition for lower magnification. but if you feel the need of wider FOV, a 2" EP is better alternative.

[jlowdo]

you're confused! think about me

[John]

The Celestron F/6.3 reducer works well to deliver a wider field of view with 1.25" accessories as it reduces the effective focal length of an 8" SCT from 2000mm to 1260mm. It can also be used with 2" eyepieces as Rae shows above however it will cause vignetting (light loss) if used with eyepieces that have a field stop larger than 35mm.  

[jlowdo]

well, just to re-cap, based on the above, very helpful, but also 'to me' very confusing advice i think for the short term i should progress with the following.... and, i'll probably be wrong...

bearing in mind the caveat that i can spend the money on this now ( which i have already with the TV 32 ), or use it on one of my other money draining hobbies...

Purchase, as Rae suggested, the 13mm Hyperion to give me 8, 13 and 22 along with the LVW's, and keep the order i already placed for the TeleVue 32 over the 36 Aspheric Hyperion based on keeping the 1.25 for the foreseeable future. with the stock Celestron 40mm as another thing to play with.

sound like a reasonable plan?

Hopefully, soon i'll be out using this more and spending less time bugging you guys. still, at least, i have doubled my post count and should hopefully soon be able to see the classifieds section and buy some more stuff ( kidding.. well, i hope i am anyway ).

thanks!

James

[jlowdo]

The Celestron F/6.3 reducer works well to deliver a wider field of view with 1.25" accessories as it reduces the effective focal length of an 8" SCT from 2000mm to 1260mm. It can also be used with 2" eyepieces as Rae shows above however it will cause vignetting (light loss) if used with eyepieces that have a field stop larger than 35mm.  

so this would be a good addition to the above, that i just summarised?\thanks

James

[Ags]

well, just to re-cap, based on the above, very helpful, but also 'to me' very confusing advice i think for the short term i should progress with the following.... and, i'll probably be wrong...

bearing in mind the caveat that i can spend the money on this now ( which i have already with the TV 32 ), or use it on one of my other money draining hobbies...

Purchase, as Rae suggested, the 13mm Hyperion to give me 8, 13 and 22 along with the LVW's, and keep the order i already placed for the TeleVue 32 over the 36 Aspheric Hyperion based on keeping the 1.25 for the foreseeable future. with the stock Celestron 40mm as another thing to play with.

sound like a reasonable plan?

Hopefully, soon i'll be out using this more and spending less time bugging you guys. still, at least, i have doubled my post count and should hopefully soon be able to see the classifieds section and buy some more stuff ( kidding.. well, i hope i am anyway ).

thanks!

James

Sounds reasonable to me... You need the 13 as a workhorse high power ep giving around 150x mag in a C8 style scope, and the televue 32mm would be excellent.

If you got a two inch diagonal, you would only need to add one 2" EP, such as a 40mm Aero.

[John]

so this would be a good addition to the above, that i just summarised?\thanks

James

If used with the 1.25" eyepieces, yes.

8, 13, 22 and 32 will form a useful set showing up to .80 of a true degree of sky (the Moon is .50 of a degree across). With the F/6.3 reducer you will get a max true field of 1.26 degrees so quite a lot more.

Most deep sky objects will fit in a 1 degree true field of view.  There is a "hassle factor" in fitting the F/6.3 reducer as it goes between the 1.25" visual back and the scope. 

The truth is, if you a really more interested in wide fields of view, get another scope !!!

[jlowdo]

Thanks Ags, i think i'll order the 13mm ( in the morning, just in case someone tells me its the wrong thing to do, but sounds like a sound plan ) ... I am not going to upgrade the diagonal until i have enough experience under my belt with what i already have, just wanted to make sure i have the right eyewear,,,,

And John, Thanks, i will ponder the focal reducer, and that would be my absolute last purchase for the time being! but maybe i should bite the bullet as it will stop me thinking whether i should or shouldn't... another scope? now that is pushing it I should make the most of what i have i think...

cheers

James

[Tinker1947]

What a confusing thread!

The hyperions are 1.25" EPs. You can unscrew the first lens group to turn them into 2" EPs, but there is no point in doing so because they do not give you more FOV than you could just get with a 1.25" EP, and they are poorly corrected, because you removed the first lens group, which is a corrector.

The aspherics are 2" EPs. They have an adapter that lets you put them in a 1.25" barrel, but doing this drastically reduces the FOV.

I didn't agree with this the comment that the Hyperions are 1.25" EP and removing the first lens group turns them into 2" EP, my Hyperions have never had the first lens group attached these Adapters reside in the boxes with the leather cases, so  rather than just say you're wrong i e-mailed Baader the reply came back as the EP are the same with or with out the first lens group which makes them either a 1.25" or a 2" EP, i class mine as 2" as that how i use them. Copy and paste of the e-mail attached....      

My question 

Text :

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I have several Baader Hyperion Eyepieces and use them in a 2" - 50mm Focuser, is it better to use a 1.25" Focuser and the screw in Adapter does this give a better image when looking through the Eyepiece.

Regards Ray

There Reply

There will be no difference optically.

We cannot judge though if you will prefer the handling then and it this might add to the perceived viewing comfort.

 

Best regards,

Service Team

BAADER PLANETARIUM GMBH

[Rockrae78]

I use the EPs both as 1.25" and 2" EPs and think that they work well either way.  The 36mm gets more use as a 2" because I like the wider views, as does the 24mm, but the 13mm and 8mm probably get slightly more use as 1.25" EPs.

Others may not agree that they are any good - I'm only going off my own usage of them and I have been extremely pleased with them (had most of them over a year now). 

[John]

Up to and including 24mm, the Hyperions are 1.25" eyepieces with the option to use them directly in a 2" focuser because a portion of their barrel is 2" in diameter. If you remove the 1.25" barrel and the lens set that is within it you get an eyepiece with a focal length of around 21/22 mm but it's not very well corrected with the exception of the 24mm Hyperion does not have a lens set in it's 1.25" barrel.