celestron 150 refractor XLT

[jimmyh1555 (James)]

I am very tempted to get one of these. It is f5, so I could use it with my DSLR camera? Has anybody got any comments/reviews? I like the idea of a refractor because I think it will be easier to look through than a Newtonian

[multiweb (Marc)]

Originally Posted by jimmyh1555

I am very tempted to get one of these. It is f5, so I could use it with my DSLR camera? Has anybody got any comments/reviews? I like the idea of a refractor because I think it will be easier to look through than a Newtonian

I think for the price you can get a much better second hand refractor from the classified here.

[brian nordstrom (As avatar)]

I had one and the optics were SHARP ! very sharp ! and the detail seen on Jupiter at about 200x was amazing for a 150mm refractor working at f5 .

CA ( chromatic aberration ) ,,, hell yes , some but not as bad as you would expect , I seem to be quite immune'd to CA , some people cant stand it but the optics in mine were very smooth had very well controlled SA ( spherical aberration ) and the coatings were awesome , I liked it a lot and only sold it because a 5 inch APO came up for sale .

AP ? ( astro photography ) Mono would probably be ok but the CA would make stars bloat quite bad so is AP is going to be your main thing , there are better scopes to be had .

Brian.

[Wavytone]

Ok.. OP do you have a mount ?

A quick search suggests $600 for the OTA, or $1100 for scope with mount and tripod.
As per previous you could do significantly better secondhand from the IIS classifieds:

- a Meade or Celestron C8 OTA,
- a 6" or 8" dob,
- new 127 mak with GOTO mount and tripod, extremely portable and dead easy to set up;
- a 150mm Mak if you want aperture and real portability; these do come up; mount and tripod up to you,

Aperture wins, every time. Only question is the depth of your pocket.

[bigjoe (JOSEPH)]

9.10pm[QUOTE=jimmyh1555;1358890]I am very tempted to get one of these. It is f5, so I could use it with my DSLR camera? Has anybody got any comments/reviews? I like the idea of a refractor because I think it will be easier to look through than a Newtonian [/QUOTE

James...

Had one of these new, and recently sold it here.

Very sharp optics as Brian says, only sold as I purchased a TS 130MM Triplet Apo.

Some chromatic aberration which can be tamed with a light yellow, or better still Baader FK FILTER...Has ASPHERIC lens...makes a difference even over ordinary f8 model.

FANTASIC on most objects for 152mm..better views than many 8 SCTs.

For colour AP stars would bloat even with a filter..long er exposures..short OK.
This is better for visual, and NOT long exposure AP.
HeEQ5 you have is an excellent size.

Planets filtered can be Stunning in it! Esp if using TV Plossls, or Takahashi or KK Orthos...even better.

PS: big step up from 120mm..sell the 120mm you have and get one ..but just not for long exposure AP...BINTEL has them on special now...maybe ask just for the OTA...VIZ F5 Aspheric.
bigjoe.

[jimmyh1555 (James)]

Thanks, Bigjoe for that! I'm getting one! My Omni XLT 120 I have had for must be at least 6 years. I am still delighted with it, but I bought a BT200 Newt 6 months ago, and have had so much trouble trying to reach the eyepiece on occasions. Some people say "Oh, you just loosen the bolts and twist it round till the eyepiece is accessible." Yes, great, only in doing so, you stuff up the alignment because you cant help nudging the dec or RA out of kilter, and then go-to is stuffed.
One thing, I must say, about the XLT 120, is, it's TOUGH. The day I received it, I dropped it slap bang onto the concrete floor and it wasn't even scratched!! Another thing about the CA problem is so simple. The lens cap comes with another capped hole in the middle. The instructions said to see a bright star, just put the cap on and use the small hole to cut down the aperture. I tried it on Sirius and hey presto, no C.A.!!!
So out goes the Newt, and in comes the 150mm XLT! PS, I only want this one for visual - I have got the 100mm Esprit for AP
My XLT 120 I shall use for Mr Moonie!

[Tinderboxsky (Steve)]

Stopping down the aperture can be a useful strategy to reduce the worst effects of CA on very bright objects as you have found using the central hole. The worst of the CA is generated in the outer sections of the lens, particularly from a diameter of 120mm outwards. When you have your scope, experiment with different size aperture masks made out of cardboard with say, 100, 110 and 120 mm diameters to see which gives you the best balance between CA and the lower light and resolution that results from the smaller aperture. The simple central hole in your lens cap is likely to make Moon and planetary views too dim if you want to reduce the CA.
You might find that an aperture stop of around 120mm is only needed for the Moon and the very bright Jupiter around opposition. All the rest you enjoy the full 150mm aperture.

Originally Posted by jimmyh1555

Another thing about the CA problem is so simple. The lens cap comes with another capped hole in the middle. The instructions said to see a bright star, just put the cap on and use the small hole to cut down the aperture. I tried it on Sirius and hey presto, no C.A.!!!
So out goes the Newt, and in comes the 150mm XLT! PS, I only want this one for visual - I have got the 100mm Esprit for AP
My XLT 120 I shall use for Mr Moonie!