Questions about my first telescope

[ricer0cket]

I'm so excited as it is on its way. I ordered the Celestron Se8. Based on what I've been researching, 2inch eyepiece gives a better view than the original one (1.25inch) right? Is it easy to replace? What are the accessories that I need?

I am new and eager to learn this new hobby. Thank you for reading

[damnut]

Hi There,

Welcome to SGL. That's a fine scope you have there. In certain circumstances 2" eyepieces do give a better view, you would need to replace the visual back on the rear of the scope and replace with a 2" version so that you can put on a 2" sct diagonal.

The 2" eyepieces come into their own on the wider fov eps in the longer focal length eyepieces, as the wider fov cannot be achieved in 1.25". However if the eyepiece has the same focal length and the same fov then there is  no advantage in having 2".

[Qualia]

Aye, I agree with Damian. In principle, 2" eyepieces should be no better quality wise than 1.25" eyepieces. 2" eyepieces allow for a wider FOV due to the diameter of the field stop inside the eyepiece. At shorter focal lengths the field stop is less than 1.25" so there's no advantage in having larger eyepieces but a couple of 2" for the longer focal lengths might be handy.

With that said, I'd get some practice in with your new scope before looking at purchasing new eyepieces. You'll then have a better idea of what you're looking for and can make a more informed enquiry.

Congratulations on your new scope and I look forward to a first light report

[ricer0cket]

Thanks for your opinions. How do I take pictures? Lol I have a Canon t3i. I think I need some adapters to connect them huh?

[russ.will]

Do bear in mind that the field stop of the 8SE is 37mm, so although you can fit a 2" visual back, the maximum TFOV you can achieve is 1.1deg, before vignetting (darkening around the edge of the view) starts to kick in. That would roughly equate to a 32mm 70deg EP, or a 27mm 82deg EP. That is just a rule of thumb though and it's not like you go 2mm over and suddenly it all goes weird!

Another thing worth having a look at is the Antares/Meade/Celestron F6.3 focal reducers as these reduce the scopes focal length by 0.63x. Think of it like a reverse Barlow for SCTs, with the side benefit of it correcting the scopes coma! Suddenly, your 25mm (for instance) EP which gives you 80x magnification, will now give 50x which is akin to jumping to a 40mm EP, but without the vignetting issues. You just screw it onto the 8SE and then the existing 1.25" visual back goes onto the reducer. Second hand, they cost less than a decent 2" diagonal, not to mention how much more expensive a 2" EPs are individually and the reducer works for ALL of your EPs.

One final point of note - I did see someone mention that with a 2" Diagonal fitted, the 8SE will hit the mount if you try to observe near zenith. With the extra length of the reducer fitted, this might suffer a similar issue, even with a 1.25" diagonal. So if you do go 2", it might be worth looking at an SCT Diagonal, which will fit closer to the scope.

Russell

[PeterCPC]

Thanks for your opinions. How do I take pictures? Lol I have a Canon t3i. I think I need some adapters to connect them huh?

My advise would be to enjoy the scope visually first and get used to finding objects before rushing into astrophotography. To connect your Canon you will need a T adapter and a EOS T ring.

You will be able to get some good images of the planets and bright objects like the Orion Nebula but the mount will not be suitable for long exposure deep space objects. Note the previous comments about hitting the mount - big issue with camera attached.

Peter

[brantuk]

Most of it's been said above - but it's also worth knowing that a 2" mounting gives a much beefier attachment for other equipment such as bino viewers, cameras, filter wheels, etc, than 1,25", which I've always find flimsy with limited room for adjustments.