Strehl ratings.

[tuckstar]

Can't remember who it was on Saturday but we had a quick discussion about strehl ratings. Here's an article which explains a bit more. This was written by John Timmins from peak 2 valley instruments who is due to give a talk at ilkeston and district astro society in July. As you can tell he is a Refractor guy.

http://www.peak2valleyinstruments.co.uk/page_1801026.html

Edited April 29, 2014 by tuckstar

[stash]

I thought that this statement was interesting:-

 

"It is true that even the budget manufacturers are starting to produce well designed OTAs but in many cases the engineering tollerances are slack - it is an unfortunate fact that even some of the so-called "hand made" telescopes produced in the UK and abroad fall in to this category." especially the last bit.

[Brantuk]

It's very true Clive - Retailers tend to produce them to what they regard as "an acceptable standard". But acceptable to them may not be acceptable to us astro punters. Need to be very careful what you get these days - it's often shrouded by smoke and mirrors.

 

(I'd treat any retailer who wasn't up front, on your questions, with major scepticism)

Edited April 29, 2014 by Brantuk

[stash]

It's very true Clive - Retailers tend to produce them to what they regard as "an acceptable standard". But acceptable to them may not be acceptable to us astro punters. Need to be very careful what you get these days - it's often shrouded by smoke and mirrors.

 

(I'd treat any retailer who wasn't up front, on your questions, with major scepticism)

Thanks Kim - its the same everywhere - who's the crook and whose the villian.

 

I feel a Ralph Nader moment coming on . Maybe the many groups in the Uk and worldwide should force the issue - Std benchmark - won't use we won't buy - I can dream can't I.

 

Thanks also for the thread I just read on SGL regarding Telrad risers - old but useful 

Edited April 29, 2014 by stash