In the market for a 70'ish mm scope

[KellyC]

Hi. I currently use a TS Optics 107mm triplet and I'm very happy with it. However, I would like something with a wider field of view that was a little more portable than the 107mm and I think that something in the 70mm range would suit.

I know this will be contentious and I know that there are a million opinions about all of this stuff, so....I have narrowed it down to:
a) WO Zenithstar 73mm f/5.9
b) WO Gran Turismo 71mm f/5.9
c) Sharpstar 76mm f/5.5
d) TS Optics 76mm f/5.5
e) TS Optics 70mm f/6
and, just for fun
f) Tecnosky 70mm f/6

All are triplets, with the exception of the WO Zenithstar.

In a nutshell, is any one of these particularly better than the others? Weight could be an issue that I need to take into consideration as I'd like to use it with my SA, rather than my HEQ6, for travelling. I could be using either an Olympus camera or a ZWO294 to image with.

Price isn't an issue.

Alternatively, convince me that your choice would be the way to go for me.

[JohnF]

I have a doublet celestron LT 70 for sale on I I S ads. Yes not the same as a triplet, but is very portable. No mount with it, but can sell it with a Wedge go suit vixen wedge mounts.

[KellyC]

Thanks for your reply, John. The focal length of your scope is 700mm, which is equivalent to the scope I already use. I'm looking for something with a shorter focal length that I can use with my current cameras. Good luck with your sale.

[Camelopardalis]

Have you considered the Sky-Watcher Evostar 72ED?

I recently got one to complement my Esprit 100 and have been pleasantly surprised so far, with no blue halos that cursed my previous 70mm scope.

[Hoges]

I have the Zenithstar 61, so this may apply to the 73mm. Definitely needs a field flattener for photography. My Orion FF for short refractors works quite well with it. Not perfect but a massive improvement on no flattener. Build quality and focusser are very, very nice. Contrast is excellent and it's not showing any false color in what limited photos/viewing I've done. Certainly more contrasty than my ED72 which is excellent value but not the quality of the WO.


Also, what about the WO Redcat 71 f4.9?

[MortonH]

Another doublet option: https://www.iceinspace.com.au/forum/showthread.php?t=195904

[KellyC]

@Camelopardalis, I went to a sky party last night and a guy there was raving about his Skywatcher Esprit 80 and he showed me some photos. I was pretty impressed.

@Hoges, I have looked at the RedCat, but it's weight is greater than any of the others, so it's out of contention.

@MortonH, I looked quickly at your ad. Not a brand I've heard of, so I'd like to do a little research, particularly regarding flatteners etc.

[Hoges]

Isn't the Espirit 80 a little heavier than the redcat 71?

[KellyC]

@Hoges, Yes, but I only just found that out today...

[AdamJL]

What's the maximum weight limit? I would also have said the Redcat 71 because it's set and forget, and little concern about backfocus.

There's also the ASKAR 400 which is a petzval so again, no backfocus issues.

https://www.testar.com.au/products/askar-400-f-5-6-apo

That's actually my next scope, when they come back in stock :)

[KellyC]

Thanks for everyone's contributions. I have decided on the TS Optics 70mm f6 with the 0.8 reducer. I currently use another TS Optics scope and have been very happy with the results. My husband uses WO and, as much as the money side of things wasn't an issue, I wasn't convinced I would get a $500-$1000 better image from the WO than I will get from the TS Optics, after all, it's just a hobby....she says...adding things to her cart...