IExos 100 counterweights


Lloyd Simons <simonsl23@...>
 

Will 5 counterweights be ok on the shaft for the iExos 100? I have a C8 I would like to use for visual and will probably need 10+lbs to balance it.
--
Lloyd Simons
Mattawan, MI
Telescopes: Astrotech AT72ED II, Orion 8" Dobsonian, Tectron 15" Dobsonian, Celestron Super Polaris C8
Imaging Camera: Canon T3i
Guide Camera: QHY5L-IIM with a 100mm CS Mount Lens
Mounts: iExos-100 PMC-8, Vixen Super Polaris
Mount Control: KODLIX gn41 mini PC, Explorestars on a Lenovo Tab 2 A10-70F Android 6.0
Software: N.I.N.A. for imaging, PHD2 for guiding, Sharpcap for PA, Cartes du Ciel, PixInsight


Jerry Hubbell - Explore Scientific VP Engineering
 

On Sun, Mar 1, 2020 at 03:33 PM, Lloyd Simons wrote:
Will 5 counterweights be ok on the shaft for the iExos 100? I have a C8 I would like to use for visual and will probably need 10+lbs to balance it.
Lloyd, 

The nominal maximum equipment weight limit for visual use on the iEXOS 100 PMC-Eight with the ST1 light duty tripod delivered is approximately 8 kg (17.6 lbs.), with the 2 2kg counterweights it is 10 kg (22 lbs.) total weight added to the mount (if you can get it to balance). We offer the iEXOS 100 HD PMC-Eight mount (https://explorescientificusa.com/collections/pmc-eight/products/es-iexos100-et) that can handle more weight. It includes the ST2 medium duty tripod and can handle about 30% more weight for a 10 kg (22 lb.) equipment capacity for astrophotography. 

The C8 OTA weighs about 12.6 lbs. which leaves about 5 lbs. for additional equipment (finder, diagonal, focuser, eyepiece). So it should work okay if you can get it to balance with 2 counterweights. If you need 3 or 4 counterweights that eats into the total weight capacity available so I would suggest that it would be better to get the accessories to turn the standard mount into the iEXOS 100 HD mount system sans the polar alignment scope. This would give you more margin and better performance.
 
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Lloyd Simons <simonsl23@...>
 

Jerry,

i have the azimuth adjuster installed on the super Polaris tripod. I would guess that is similar to the ST2? I currently have 3 weights for my current setup but that is not enough to balance the C8 OTA alone (without a finder, diagonal etc). I’m not sure 4 will be enough that’s why I asked if 5 would be too many. Thanks for all of the info.
--
Lloyd Simons
Mattawan, MI
Telescopes: Astrotech AT72ED II, Orion 8" Dobsonian, Tectron 15" Dobsonian, Celestron Super Polaris C8
Imaging Camera: Canon T3i
Guide Camera: QHY5L-IIM with a 100mm CS Mount Lens
Mounts: iExos-100 PMC-8, Vixen Super Polaris
Mount Control: KODLIX gn41 mini PC, Explorestars on a Lenovo Tab 2 A10-70F Android 6.0
Software: N.I.N.A. for imaging, PHD2 for guiding, Sharpcap for PA, Cartes du Ciel, PixInsight


Skull HQX
 

Hi Lloyd,

I've tested balancing with my C8 on the iEXOS-100 (there is a topic with a picture about that). Imho it is not a good combination for this specific mount, even if using a heavier tripod, like I did. Regarding weights, the trouble with the standard weights is they are a bit small and have little diameter. So, when 'stacking' weights, you quickly end up placing upward on the counterweight bar where they will be less 'efficient'. You would need to add quite a few and thus create more total mass. This is just not that ideal. I can attest it is impossible to balance the C8 with the two standard counterweights. I'm quite sure you won't get it to balance with 3 and even 4. I needed a larger diameter and mass counterweight (5.3 kg) and a single standard weight (about 1.2 kg) to get it to balance. That tells me it would probably not even balance with 5 standard weights.

I would presume you will need to attach a diagonal and eyepiece and finder scope, or a astrocamera/DSLR. This would add weight as well. Maybe you want to add a guide scope and camera too. It would add something like at least 1 kg. I just weighed the C8 OTA and it is about 5.8 kg bare/dry. So without large diameter counterweights, it will be very difficult to balance within the specification.

The OTA plus kit would at the very least total 7 kg and the counterweights needed (using a larger diameter one, like I did*) is about 6.5 kg. Almost 13.5 kg in total, which is 35% above the specced maximum capability for the iEXOS-100 plus heavy tripod. And I'm not even sure if your super polaris would count as one, as I'm not familiar with it.

*) The larger diameter counter weight would need a custom adapter as well, because the iEXOS-100 counter weight bar is 14mm and you would need something to reliably adapt the ±21mm hole in that larger counterweight.

Personally I ended up shelving my C8 and buying a 127mm Maksutov which is a much more feasible telescope for the iEXOS-100. Note, I only use this setup for planetary and lunar astrophotography. For deep sky AP I use much lighter prime lenses and a DSLR/SLR camera's. Those are loads the iEXOS-100 would be perfectly capable of.


Kai Gr <hififreak777@...>
 

The iExos-100 isnt made for such lager tubes like the C8 OTA. It is a Mount for easy Traveling and use of small Apo´s and Photolenses. With the C8 OTA and your Goal for Solar Photography i highly Recommend a much larger Mount.
The 2 Standart Counterweights are quitely enough to Balace my Setup with a Canon 70d and a Tamron 150-600mm G2. Any Heavier i would need also a extra Counterweight but im fine with this because its exactly what i was lookin for.