TAL 125R First Light

[moondog]

Well - with my old TAL 100RS hopefully winging its way to Dominic (domfog) up in the North East, it was time to try its replacement the TAL 125R.

This is a 5 ins F9 refractor. This TAL has a lens cell you can collimate - unlike the 100RS. Not that the new scope wants collimating, but at least I could have a go if necessary.

The 125R is not a 'drain pipe' design, like the 100RS, but has 'champagne flute' styling towards the objective lens. Don't think this helps any but it looks good. The 2 ins focuser and the rest of the scope is like the 100RS. The finish on the 125R tube and the lens cell assembly is an improvement on the 100RS - but for the extra cost it should be.

Tonight was - like a lot of others lately - not brilliant, but at 10-30pm the moon came out from the clouds so I set the scope up.

Slewed to the moon - the HEQ5 Go To motors are very fast - just in time to centre the moon and focus the 15mm ( 75x) lanthanum when the clouds started rolling in ! Held the scope on the moon for 10 mins or so and the clouds kept parting and rolling over. Enough for me to see that the scope was optically OK. The CA on the moon's edge seemed even less than the 100RS, which was slightly surprising (as it's a larger objective lens and a faster scope)- but welcome. The moon then disappeared.

Looking round the sky the only other object I could see was Jupiter that had just come out of a cloud bank. At 75x it looked a fine sight, with visible banding and 4 satellites plus, I think, a faint star. What again surprised me was the very small amount of CA. For the 100RS I had bought a fringe killer to help with CA on Jupiter - this isn't necessary with the 125R. Even with the far from perfect sky I managed to get the best view of Jupiter yet with a 9mm lanthanum at 125x.

I look forward to testing the scope on better nights,but the first light shows the promise of what I hope is to come.

MD

[GazOC]

Glad you like your scope MD. A decent 5" f9 should n't need a MV filter (unless you're a fussy [removed word]), unfortuneatly James has got mine...... :)

If you don't mind me asking, how much did it cost?

[OXO]

Cracking scope it is too Gaz

Nice report MD should give ya plenty of fun!

James

[FLO]

Thanks for the report MD,

blumming good those Tals

Built to last too...

[moondog]

Gaz

I was comparing the 125R against the 100RS for CA. THe 100RS has far less CA than a lot of other fracs I looked at before I bought it. I am a bit fussy about CA but the 100RS had only the merest film of yellow and magenta around bright objects - the Moon and Saturn say. I mainly got the fringe killer for Jupiter - which can be the problem planet whatever your scope.

I struggled to see any CA around the moon with the 125R and hardly any magenta on Jupiter. The Jupiter image was also brighter and more defined with the 125R

I have returned the fringe killer (didn't really like the yellow moons around Jupiter!)and swopped it for a CLS. Now I've got a DSLR I want to have a go at the fuzzies.

As to cost, the 125R retails at £599, I paid £570. You do get a good portable case for the OTA with the 125R though. The TAL100RS is definitely underpriced at a retail of £199 and a real bargain.

I'll only know if the 125R is overpriced when I've been using it in anger!

As Steve knows, I did look long and hard at buying the TAL 200K 8 ins Klevsov Cassegrian as I could have paid only £80 more for it. In the end the frac won out over the 200K for its faster cool down time, 2 ins focuser and better image contrast.

MD

[geppetto]

Thats a great start MD

Have lots of fun with your new scope