New Binoculars

[mch62 (Mark)]

Eye relief is 19mm which is actually pretty good and able to be used by spectacle wearers.
The CA is about that of an 80mm f5 Achromatic refractor at 20x.
These are about an f4 system to keep them compact and lighter in weight.
There 5 cm shorter than the light weight 20x80 model.
Remember these are not APO triplets but are designed to give an acceptable amount of colour in a shorter focal ratio system.
Have just had a looky through and collimated Argonavis 's new 22x100's Bino's at Atro fest and found the 20x80T Ca to be as good as these if not better as far as colour.

Really I don't use binoculars for looking at the planets or the moon so colour on these brighter objects is not a concern .
As far as any flaring the simple lens shades I quoted above reduce this but the interiors need better blackening especially as there are no baffles.
For me I use them solely for deep sky use and they perform very well in this regard and if carefully collimated will give pin point star images to the edge of field with dark back grounds.

One tip when using the fold down eye caps when things start fogging up at the eyepiece , fold the caps back.
They act as little buckets and trap heat from your face.
Things got real cold on Friday night at Astro fest with heavy frost by 12 midnight and all the hair dryers starting up, I found the eye caps to be a nuisance until I folded them back.

All those that had a look through them liked what they saw some were able to hand hold them while others were not. I do hand hold and also use a tripod .
O yes the case is the pits , turf it and get something better.
Can't expect to much for $250.

Mark

[fringe_dweller]

Thanks again Mark and Beren! these binos just get better - and didnt think of folding down the eyecaps! when i said the eye relief was average - i really should said I was including the apparent field of view of the ep's seeming narrow or average in the equation? hhmmm - the sweet spots of focus arent hugely wide? (could be my eyes?), it seemed from my brief use of them. But I am not an optics expert by any stretch of the imagination hehe - I am like one of those people that like to drive cars ect. but i dont really enjoy tinkering with them or doing them up as much as a LOT of people seem to (i wish i was!) - but i still love to go for a spin in a nice one and give em some stick now and then
Kearn
PS I have to make a correction - I said it took a week to receive my 20x80 triplets here in Adelaide from Lee Andrews - to be accurate it was actually much shorter than that - it was about 3 - 4 working days, as there was a weekend in the middle - feel better for that