Celestron C4R 1st impressions
Posted 24 September 2003 - 05:24 PM
Out of the Box
- Noticed two small issues. There was a spot of bare metal on the OTA near the focuser about 5mm thick. The OTA was not dented. I happened to have some black paint and touched it up. You wouldn't see it now unless I told you about it. Also the small plastic cover that goes on the mount was broken. I consider both of these negligible issues for a 400.00 telescope and did not contact Astronomics
1st Impressions - this scope is long, 44 inches from dew shield to eyepiece with drawtube in proper focus position.
The mount does support the OTA well enough though for visual work.
The 99.00 accessory kit contains real eyepieces and having checked them all out, this is a good value. The 4mm and 6mm eyelenses are small, but fully functional.
1st light - Of course, I set the scope up and trained it on Mars about 2 hrs before transit. the views were not good at all. I initially was disappointed in the scope, but after spending a really great 2nd night with it, I realize how bad the seeing was on the 1st night. Best views using the supplied equipment was 222x (Barlowed 9mm). Best views with some of my own equipment was 250x (5x Powermate and 20mm Plossl). I thought the color correction would be better for a longer F/L instrument, but maybe I'm just spoiled by the ED-80's optics. I observed Mars for 2hrs last night. Detail was very good.
Put M57 in the eyepiece. It was about 1 hour after transit and the viewing angle was somewhat awkward, but the little donut shaped planetary was fun to find! Best views were had with the 9mm Plossl (111x)
M13 was next. It was lower now in the western sky and the viewing angle was much more comfortable. Best views came using the 15mm Plossl (67x)
M45 (the Pleiades) rising in the east after midnight. With the supplied 32mm Plossl at 31x the Sisters were framed nicely.
Double Cluster - Very nice indeed! One of my favaorites with the 32mm Plossl.
If this is your 1st scope, here are a couple of things I would consider upgrading or modifying:
The 6x30 finderscope works, however, I'm used to a 9x50 and put my own on it. It's just easier to find stuff.
The focuser is stiff. I have some lithium grease and will clean the focuser and regrease it for smoother action. The more pressure you have to put on the focus knobs, the more the image will shake while you are trying to achieve best focus.
Diagonal - the diagonal is acceptable, but I did notice an improvement when I put my Lumicon Enhanced in. Contrast just seemed better.
Well, those are my 1st impressions. I hope you find this helpful.
Posted 24 September 2003 - 06:56 PM
Posted 24 September 2003 - 07:19 PM
Indeed, f/9.8 is only medium focal ratio and f/15 or f/20 would be the classical focal ratio for a 4-inch achromat. So the nasty purple is still there and will be more obvious on Jupiter. I would be interesting how it would compare with your Orion 100mm f/6 though.
Posted 24 September 2003 - 08:16 PM
Ron, I enjoy your Light Cup series very much! Thank you for putting those out.
The Astroview 100/F6 has been on loan to an enthusiastic 13yr old since July. I think I'd get a black eye if I tried to get it back from her. She's a friends daughter and I love her energy.
From what I remember, I would rate the color correction in the C4R as at least a 1/3 or more better than the 100/F6.
I have since disassembled the focuser and cleaned/regreased it. The action is much smoother now.
I plan on evaluating the Eyepieces in a little more detail tonight. I have a set of Celestron Ultimas that should be a good test.
Posted 24 September 2003 - 08:31 PM
Posted 25 September 2003 - 03:38 AM
Posted 25 September 2003 - 04:51 AM
Great report of an enjoyable scope! To quote someone at excelsis:'A perfect telescope? Hardly. A great astro toy? Absolutely. Hey Just (Ermult), are you reading this?
Posted 25 September 2003 - 11:52 AM
I think that quote sums it up perfectly!
I spent another great night observing with it last night. For 500 bucks, (400 for scope and 100 for EP's) this is a complete observing sytem.
I checked out the EP's in more detail last night, but will toss that into another post.
Posted 25 September 2003 - 02:31 PM
Scope looks very nice- I'm beginning to get into refractors too! Regarding Colour Correction, have you tried the Baader Contrast Booster filter? It was made specially for the modern doublet achromats, and works wonders on my 102mm f5.
Just a thought....
Posted 25 September 2003 - 08:58 PM
A couple of follow-up notes.
The scope comes with a collimation EP, but the instructions don't address using it. I had to go to www.telescope.com and get the product instructions for the Astroview. It's on page 15.
The focus knob still bugs me a bit in that it's cheap plastic and the knobs are kinda sharp. I'll look into getting a better set.
There seems to be a bit of image shift when focusing. I'll try and tighten that up a bit.
I put the collimation EP in and saw two circles not quite converging. I wound up tweeking the collimation on the lense. The scope tested well on Altair and Polaris. I think it improved performance on Mars and Saturn. This was my 1st long look at Saturn through this scope and it didn't disappoint!
Saturn isn't very bright, so false color isn't really an issue. The C4R performed very well At 4am, Saturn was finally getting out out of the soup. Cassini's division was easily detected and I got what I think was a darkened central band with the 5mm Ultima at 200x.
The Double Cluster is a great target for this scope. A 30mm Ultima shows a 1.5 degree field and is totally AWESOME!
I posted a separate note about the eyepieces and observing last night.
Posted 25 September 2003 - 10:18 PM
PS - only trying to help you spend more dough :money:. Oh, ditch that diagonal and get a nice one like the Tele Vues and the scope will do even more for you.
Posted 25 September 2003 - 10:33 PM
That is a very nice looking set-up-mount and all-congrats! Is there any way you can estimate the size of the tube rings and let me know, without having to remove the tube? If so, I'd definitely appreciate it...thank you.
Posted 25 September 2003 - 11:43 PM
I've got a 24mm Panoptic on the way and a WO 2in Diagonal on backorder with Anacortes. Right now I'm using a Lumicon Enhanced 1 1/4 inch Diagonal til the WO gets here.
Kowen, the tube rings are the same ones as the Astroview. I've interchanged them and the hold the C4R also. If you have an older C102, you might want to double check. Orion's got a generous 30 day return policy, so if they don't fit you can send them back.
I think these are the ones you need for a C4R.
part # 07371 100mm diameter.
BTW Kowen, where are u in Louisiana? I'm originally from a small town outside Lafayette.
Posted 26 September 2003 - 12:14 AM
Thanks for the information. I bought an ota, it is about 2 years old off of Astromart, should hopefully get it by Monday (sooner would be nice...). The owner said he used some from a 90mm refractor...did not say what size they were. I may go ahead and order some, if they don't work, send them back.
I am in Lafourche Parish, about 1 hour S/SW of New Orleans, a native. Do you get back here much to visit family?
Posted 26 September 2003 - 12:35 AM
Good luck with the rings!
Posted 26 September 2003 - 12:45 PM