BinocularSky

Sorry, but I'm going to be absolutely frank with you: the Barlows and erecting lenses provided with that telescope are of extremely poor quality (I know because one of my students has the same accessories with a different Seben scope); you will get better image quality without them.

I've heard good things about BST's, can anyone confirm this?

Yes. I have the 18mm BST Explorer. Very nice eyepiece and astoundingly good value for money.

On the batphone, so expect typos...

For what it's worth, I have just updated my page Choosing a Basic Eyepiece Set, which has a slightly different emphasis of criteria to that of the OP's generally excellent advice. (The one major difference I have is on pupil dilation and age)

I will always be grateful to Sir Patrick, who is one of the two (the other being Sir Fred Hoyle) who inspired my passion for astronomy. I have two abiding memories of the last time I met him (22 years ago, when I was making a BBC Radio documentary on light pollution, to which he gave freely of his time): his great warmth and generosity of spirit ..... and the pain in my foot as he stood on it as we were backing out of his octagonal observatory! :-)

The next time I look at a starry sky, I will pause and remember this great man.

I'm attempting to date my Celestron C8

Contact Rod Mollise (aka "Uncle Rod") of the Mobile Astronomical Society http://skywatch.brainiac.com/astroland/ -- if anyone can help, he can.

I now have the following pages for binocular observers on my web site:

Object Search based on your location, binocular size, class of object, constellation, etc

Specifically for UK-latitude observers:

Object of the Month A new object every month

Whole Sky Maps Interactive maps of the whole sky, clickable for various objects, taking you to finder charts and more information for each.

Transient Objects and Events Regularly updated for things like supernovas, comets, occultations and close conjunctions visible in binoculars

tetenterre, so you think that's bad enough to exchange it for other? Could I have any problem in the future caused by that front glass problem?

Lens groups are designed to work at a specific spacing. If one of the lens elements moves, the lens cannot work properly at all positions of the moving element. Also, the mere fact that it moves at all is indicative either of very poor quality control or that somebody has "had a go" at the binocular.

Should the neckstrap be included in the package? Because it didn't came.

No idea. Is it listed on the box?

By the way, when I focus on an object, the "outside area" looks a bit unfocused whilst the "inside/center area" is focused. Is it normal ?

Yes, it is normal. It is due mostly to field curvature and the fact that aberrations like coma and astigmatism are more apparent at the edge. It tends to be more obtrusive in budget binoculars.

The question is, should I try to exchange these binos because of that?

Yes.

Anyone know of any other tests I can do to check?

BinocularSky - Evaluating Binoculars for Astronomy

Branded "Auriol" in my local Lidl, but appear to be bog-standard United Optics/Kunming BF4 10x50; £16.99. Curious that it is said to have "Exceptional viewing quality with 50mm BaK-4 lenses" -- I'm sure I would take great exception to the viewing quality if there was BaK4 glass, even Chinese BaK4 glass, in the lenses.

To check collimation, especially with eccentric rings, I found this page and if the sun is visible this weekend I'll see how near or far they are actually collimated.

You might also like Rafael's lamp method if the Sun doesn't co-operate; I prefer his autocollimation method

Also, take a look at Konstantinos's (user-name here= Pleiades) use of Bahtinovs to check alignment; I've tried it and it works very well.

Ziess BGAT 10x40 nearly 20 years old and perfect!

Opticron 10×42 BGA: Easily hand-holdable; very good optics. Use it as a quick "grab and go" and as a hand-holdable adjunct to my big binoc.

Strathspey 10x50 Marine: Lives permanently in the car; extremely robust and reasonably good optics.

Miyauchi 20/37x100 Bj-100B: My main observing instrument; rarely use the x20 eyepieces. In preference, I put it on a UA T-Mount, but also have a Manfrotto 475/501 combo for a more portable option.

i'm surprised this thread isn't the 15x70 landslide i thought it'd be. lots of 10x50s. i'm surprised there aren't more 7x50s.

A 10x50 Porro is almost certainly the most versatile medium-to-low-priced binocular available, which would explain its popularity. There are maybe half a dozen objects (I can only think of three off the top of my head) that are better in a 7x50 than a 10x50.

I've just added a page on Binocular Basics to the binocular section of my web site.

Topics

1. Aperture, Magnification and Field Size

2. Exit Pupils

3. Coatings

4. Prisms

5. Focusing

6. Letter Designations

Yes I hear their service is good once they've got your money but until then..would touch them with a barge pole USELESS!!!

The latter bit is not my experience at all -- I found them remarkably helpful and they went the extra mile for me (see my post in "Supplier Reviews).

Ordered a padded telescope bag on the afternoon of Saturday April 02, with standard delivery. I received an email on Sunday, telling me that it would be dispatched on Monday. It arrived before midday today (Wednesday April 06); I don't think four days, two of which are a weekend, on an order from Germany, is too bad at all. Additionally, TS communicated every step of the way (receipt-of-order/processing/dispatch-with-tracking-number) so I knew what was going on and what to expect.

They certainly lived up to the second word of their name.

Wanted an HEQ5 tripod only (no mount); enquired via FLO's "contact" on web site. The following time-line gives a good impression of how things proceeded.

March 30:

12:11 -- I sent my enquiry.

12:44 -- Reply from Martin saying they don't do it but will see if supplier can provide one.

14:15 -- Martin emails to tell me he can get it and tells me the price.

14:49 -- I email Martin to enquire how to pay for a non-stock item.

15:05 -- Martin emails with comprehensive details.

15:11 -- I complete the order and email Martin to thank him.

15:14 -- I get an order-status email to tell me that the order has progressed from "in packing" to "in shipping".

15:15 -- Email from Martin saying that he has taken one from a stock mount so I don't have to wait.

March 31:

12:20 (approx) -- Tripod delivered. Well packed and perfect for the job.

Needless to say, I am very impressed. Martin's customer service cannot be faulted -- the whole time there has been an attitude of "we will do our best for the customer". A mere 21 hours from order to delivery is far better than I expected.

Thanks for that, Keith; exactly what I wanted to know. (Conditional alignment is when the optical axes are parallel, but are not -- in your case -- parallel to the centre axis. In a "normal" binocular, it is when they are not parallel to the hinge.)

Keith:

Firstly, what a superb job!

Secondly, two questions:

Collimation? (as opposed to conditional alignment)

Thermals from the observer?

A free battery is generally a "good thing". Use it till it goes belly-up....then get your deep cycle one from any decent chandler or alternative energy supplier (they are also used with PV arrays). Google is your friend....

The thing about vehicle batteries is that they are not intended to be heavily discharged (they start the vehicle, then get recharged by the alternator). For this reason, the lead plates are thinner. For the sort of thing we use batteries for, you really need what is called a "deep cycle" battery; it has thicker plates and is designed to tolerate heavy discharging. They are often sold as "marine" batteries.

That said, your transit van battery will not fry your kit (as long as you connect it correctly!); it may, however, not survive a winter or two of deep discharges.

Just a thought: Is there any reason that I shouldn't use a 1.5W solar trickle-charger to keep a powertank topped up? (I presume they have cheap SLAs inside.)

Some may find these pages of mine useful:

Evaluating binoculars

Hand-holding binoculars

Mounting binoculars