Altair Astro 10x60 finder

[West End Wendy]

Just bought one of these finders.

It's a beautifully made little scope with some great features and I love using it, but the distortion at the edge of the field is really substantial. Stars become lines running parallel to the field stop.

Is this coma? I thought coma was a property of reflectors only.

I was expecting sone edge distortion but it's considerably less pronounced in my cheap 10x50 binoculars.

It's a minor problem, of course, because it's pin-sharp in the central 75-80% but I must admit I'm slightly disappointed because the edge of the field is often what you end up looking for when you're star hopping and in all other ways the finder is really top quality.

Tim

[Macavity]

I bought a Telescope Service (DE) straight through 60mm super-finder. I believe they also appear under the APM badge? It got absolutely slated in the recent S@N review (a mere 60-something percent! LOL) as a guide scope. Chromatic Aberration t'boot? An Achromat, doubtless. BUT I have yet to really test it, and my eyepieces are ALL doubtless dodgy at F4... I live in hope.

[brantuk]

If you have Astronomy Now magazine - Olly makes some comments on it in his review of the Altair 115 EDT (I think it was June or July issue this year). I believe he had a glass expert with him at the time too. Not had first light with mine yet so can't really offer anything other than that at the moment

[MaxLux]

Hi Tim,

I bought the same finder last week when I was holidaying near their Aylsham shop, currently awaiting delivery as the only one they had was a demo model. I hope I don't get the same problems you've experienced, it wasn't exactly cheap!

[West End Wendy]

Thanks.

I had a look at Olly's review from AN but he only briefly touches on the finder, and only really to praise its various features (which I agree are excellent).

I'd be interested to know what you guys think when you try yours in anger.

Cheers,

Tim

[West End Wendy]

Having had 4 months to get to know this finder I thought I would post again having had the benefit of a bit of real experience with it.

I've learned to love it, despite it's faults and despite considering going back to my old Skywatcher RACI, it is still sitting on my scope as we speak.

The bad:

1. Very elongated stars in the outer 10-15% of the FOV. Ok, it's a short focus refractor with a cheap-ish eyepiece attached, but I was expecting better.

2. No spring-loaded thumbscrew. If it had one it would be much, much, much, much better.

3. Illumination attachment is heavy enough to occasionally pull eyepiece out of focus.

4. No noticeable difference between it and 50mm finder - exit pupil is 6mm, and I'm over 40, so unlikely I would ever see the difference.

The good:

1. Beautiful views in the centre 80% of the FOV.

2. Rotating diagonal is absolute godsend - couldn't do without it anymore.

3. Illuminating reticule works well, despite issue above

4. Fits standard SW finder dovetail.

5. Well made and looks great.

In summary, a cautious thumbs up.

Tim

[Zul]

I want this finder too.

[Moonshane]

Could you buy (or use one you may have) a TV plossl and maybe this would improve it greatly?

[Deneb]

I wouldn't say its great, the whole point of the Finder the star is meant to stay static in the centre fov, when the diagonal is rotated the internal prisms don't keep the star centered...

[West End Wendy]

Could you buy (or use one you may have) a TV plossl and maybe this would improve it greatly?

Yes, I have considered this, but I would miss the cross hairs.

[West End Wendy]

I wouldn't say its great, the whole point of the Finder the star is meant to stay static in the centre fov, when the diagonal is rotated the internal prisms don't keep the star centered...

To be honest, I always assumed the star would move when I adjusted the diagonal - after all it does in the main telescope when I turn the diagonal on that - I'm not really sure how you can prevent that happening. What happens with rotatable focusers? I've never owned one.

I do wish it was just a little easier to adjust though, then it would be less of a problem.

[Deneb]

Well the rotatable diagonal should only give a person a desirable viewing angle not knock the star out of the centre, whenever I have rotated a diagonal in my scope, that star stays dead centre...