Telescope Connection Breakdown - right to left
Recommended back focus to flattener for use with the GT81 telescope is 62.1mm
Camera: threads 42mm female, width to sensor is 17.5mm
Adapter: threads 42mm male to 54mm male, width 2mm
Filter wheel: threads 54mm female on both sides, width 20mm
Adapter: threads 54mm male to 48mm male, width 2mm
Spacer: threads 48mm female on both sides, width 16mm
Flattener: threads 48mm male to 63mm male, width is set to +5mm
Telescope: threads 63mm female
Precision machined aluminum and steel. 40 years experience making EQ mounts. Unlike other companies, when Losmandy advertises a weight capacity that is the actual photographic weight capacity. (If you buy an EQ mount from another company expect the recommended photographic capacity to be half the advertised capacity.)
APO Triplet Refractor. Refractor telescopes are the most like camera lenses and so the easiest to use for those of us coming from a photography background, and have low comatic aberration. The APO Triplet part just means that your money is being spent on correcting chromatic aberrations.
A field flattener works to correct distortion and focus issues around the edges of the image. Don't even think about shooting full frame without one. A Reducer trades focal length for speed (no I will not argue the technicalities of this point with you).
Not wanting to spend time fighting my photos I wanted a camera that was capable of usable one shot color images. Pretty much a cooled version of the mirrorless I already owned.
Sensor: Sony Back-illuminated 26mp APS-C Color CMOS.
Quality Specs: 3.76 pixel size, 50ke well depth, 14 stops dynamic range, 80% peak QE
Welcome to dedicated astro cameras; they're stupid. The ASI2600 pretty much consists of a sensor, an air conditioner, and a dew heater, that's it, no brains. You can use a laptop and freely available software (linked to at ZWO site) or you can buy one of these dedicated astro computers and control the camera over WiFi with an app on your cellphone. This Pro version also includes USB and 5v power ports for accessories.
A mono uncooled astro camera, with the Mini version designed primarily for guiding. It has a fast video rate so can be used as a planetary camera also.
Quality Specs: 3.75 pixel size, 14.5 well depth, 11.2 dynamic range, 75% peak QE
This will make you the envy of all the other astrophotographers. Electronically controlled focusing that can be fully automated to recheck focus based on time passed and/or temperature change.
Power Distribution Unit = PDU. The ASIAIR has PDU capabilities built in but can't handle quite as much power as this, and this has a few more ports. Coming with an external temperature/humidity sensor it figures out the dew point at your telescope and adjusts the dew heaters as necessary using the 2 dedicated dew heater ports.
You can never have enough stuff:
SVBONY Universal Dovetail Base - also know as a Synta-style base. Buy 2 of them. There are screws in the telescope just for 2 of these brackets. This is the proper way to mount things to a telescope.
Powerbox mount - if you look at how the Pegasus Powerbox is attached to the telescope in the image above, that is done with this custom mount. The options you want are the PPBA-Bracket and the Synta-Bar-50mm (he added the 50mm bar at my request just for this build). Great guy to work with if you ever need custom 3D printed astro parts.
Dew-Not Heater Strips 6" - for guide scope
Dew-Not Heater Strips 14" - for main telescope
M54 Male to M42 Male Adapter - connects the filter wheel to the camera without having to use regular screws
M54 Male to M48 Male Adapter - an adapter likes this comes with the filter wheel
Radian Triad Ultra Filter - quad narrowband filter which only allows nebulae colors through. Nothing else like it in the industry. Expensive but amazing.
ZWO Duo-Band Filter - dual narrowband filters out that pesky light pollution, also removes moonlight.
SVBONY UHC Filter - light pollution filter
Baader UV-IR Cut Filter - this filter cuts star bloat when using a dedicated astro camera. This reduces, while the Radian filter actually removes all star bloat.
SVBONY Dark Frame Filter - just makes it easier to shoot dark frames
Losmandy Universal Dovetail Plate - 14" - bigger rock solid plate designed for the Losmandy mount. I mounted the telescope's V plate directly to this one.
Losmandy HD Tripod Foot - glow in the dark anti-vibration pads
Losmandy G11 RA Extension Kit - moves the telescope slightly further away from the mount, also lets you break down the mount for travel.
15V 8A Power Supply - to power the mount. Losmandy says it tracks better if you use 15v.
12V 10A Power Supply - to power the Pegasus Powerbox which powers everything else.