First Light Nagler 17mm T4

Tamtarn · #1 20-10-2006, 06:04 PM

Yesterday our Nagler 17mm T4 EP arrived

We have been blessed this week with clear skies Sunday Monday and Wednesday and last night clear again...............Conditions 7/10

The EP is heavy 26 oz but we had no problems at all with the balance on our dob even when it was in horizontal position.

The EP has an adjustable eyeguard which when pulled upwards it clicks into 5 different positions enabling you to choose the most comfortable eye relief and FOV. This took both of us quite a while to get used to. But once the "sweet spot" is found......for us position 3.....it was very comfortable and enabled us to get the advantage of almost all the 82 degrees FOV we're not sure what the "actual FOV" is at this setting but definately gave us the spacewalk feeling.

We chose a few favourite targets Tarantula and Helix nebulae and NGC253 Silver Coin galaxy.

It was wonderful to see in the FOV of our EP the same wide field vision of Tarantula and surrounding nebulae as we have seen on images submitted by members of IIS. The contrast of the EP is exceptional and with the DGM filter the view in the EP was wonderful. We browsed the SMC and LMC and were blown away seeing the number of nebulae in the one FOV. Then to Helix, not always a lot to see with this one. It was definately brighter sharper and much easier to define shape.

NGC 253 was seen with much more detail than we have seen with any of our other EP's. The Panoptic and the two Pentax's. The detail around the centre core and dark lanes clearly visable.

After midnight across the sky from North to East to South was just a mass of stars and nebulosity everywhere. So we were able to catch up with Orion M42 and Eta Carina.

Well !! such fantastic vision of both of them. A large view sharp and great contrast. It was hard to tear ourselves away. (Yes David spent a number of hours observing this time )

So I decided to do some galaxy hunting using the Nagler. Much to my surprise I found it easier to locate faint fuzzies with the 17mm than the 27mm. The contrast made some of the fuzzies seem to jump out at me. Then I spent a lot of time at the EP taking in more detail. Altogether there were about 12 here and there in different areas all found without a go-to. The same thing applied here as with the nebulae.....A lot more detail and I was able to see spiral arms and face on galaxies more defined.

We actually spent the whole night with just the Nagler in the scope and saw magnificent vision of the large nebulae, large galaxies, global and open clusters very sharp and bright and were still able to get very good detail on the fuzzies.

We're very happy we decided on this EP. The 17mm focal range suits our needs perfectly and the eye relief on such a wide field is excellent and very comfortable.

Spending up to 5 hours with just the one EP says it all .

Can't wait to try it out at Snake Valley in November

Barb & David

janoskiss (Steve H) · #2 20-10-2006, 06:29 PM

Wow! It sounds like you've got a real winner there!!

If you cannot be bothered to change EPs, and just looking for a comfy cruise of the night sky, the 17mm T4 is certainly the EP for the job in the 12" Dob.

I am surprised to read that you see more detail in galaxies like NGC 253 with the 17mm T4 than with your shorter FL Pentax XWs. After studying an object for a while in the 17mm, I suggest you swap over to the XW-10 for a closer look. In my experience in side-by-side comparisons in the 12" f/5 Dob I could see more detail in galaxies with the XW-14 than with the 17mm T4 and more still with the XW-10, and sometimes a bit more again (or more precisely, the same detail seen easier) with the XF-8.5. The XF-8.5 rules on most planetaries - well not big ones like the Helix obviously

. (My XW-7 is a more recent acquisition and I have not used it enough on faint fuzzies to tell where it fits in.)

Tamtarn · #3 21-10-2006, 08:59 AM

We will certainly do a comparison with the Pentax's Steve but from memory we hadn't seen 253 as clear and sharp and with so much contrast before.

Maybe it was better seeing conditions that night, also we wanted to give it a good workout so didn't bother to use the other EP's.

Will get back to the post after our next good night out

beren · #4 21-10-2006, 04:27 PM

Congrats on the new eyepiece , your experience sounds very much like my own when I used my 22mm nagler for the first time and many times since.I often use it solely through an evening

or matched with a 2 inch powermate...enjoy guys and thanks for the post great to hear

MarkN · #5 21-10-2006, 10:33 PM

I know exactly what you mean Tamtarn. My 17 T4 was bought for the Meade and while I was impressed with it there, it really needs a reflector to do it justice.

The 73X coupled with the 82 deg. AFOV means it spends all its time now in the Newt.

E. Car. and the Tarantula are stunning with an OIII filter.

Great to read you're happy with it!

Mark.