6X30 FINDER ON AN ETX-90 Last updated: 9 March 2008

Sent:	Sunday, March 9, 2008 10:47:36
From:	The Brown Family (chrisbrown4@cox.net)
Im still enjoying my '90, I found R Leonis the other night, and Saturn
still looks sharp at 198x! After 5 years, still no collimation
necessary!

BTW, I sent the Karma Dogs after those telescope thieves...my regrets to
you...

I wanted to pass on this finder modification to you, and your readers.
Best Regards,
Chris Brown

Using a 6x30 finder on an ETX-90.

I found out some useful information on converting a standard 6x30 finder
to an ETX-90 Mak telescope.

I know it is not a unique conversion, but I have a few tips that might
help...

First, the ETX-90 finder bracket is smaller than the ETX-125 unit (not
sure on the 105, I assume that it uses the 125 unit) and they are not
interchangable without a few modifications.

Secondly, You can fit a 6x30 finder in the 90 bracket with minor
modifications. (Thanks to Geoff Gaherty on this one!)

I happened to have both brackets on hand, and I realised that a 6x30
finder (in this case, an Orion straight-through unit) fits easily into
an ETX-125 bracket without disassembly.

I then had to modify the 125 finder bracket to fit my ETX-90. First, I
notched the right corner by the mounting screw to match the 90 bracket.
Just a few cuts with a hack saw blade is all thats needed for the
bracket to sit flush on the OTA.

Next, hog out the mounting screw hole (I used a dremmel) and reinstall
the stock bolt with a small washer.

By now, you will see that the front tab of the finder bracket won't feed
into the locating slot, in fact it is about 1/4 inch above it! You can
place some foam or velcro under the front tab to stabilize it.

Using the 125 finder bracket on your ETX-90, you have many more finder
options, (Props to Mark Mittlesteadt for using an Orion RACI!). The
mount is not only stable, but the adjustment screws are easy to get to
and manipulate!

I am using an Orion 6x30 straight-through on my 90, and even though I am
using a Lumicon diagonal out the back port, I have no clearance
problems.

Using this finder, along with a red-dot finder, It is now alot easier to
find deep-sky objects using the star-hop method and simple maps!

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